August 2016 | Volume 18 Issue 1Editor : K.K. Mitra, Associate Editor : Dinesh Rawat BULLETIN

ASHRAE INDIA CHAPTER For the

HVAC&RIndustry

K.K. MITRA

President

ASHRAE India Chapter

PR

ES

IDE

NT

IAL

ME

SS

AG

E

The BOG for 2016-17 was installed on 8.7.2016 by respected Dr. Prem C. Jain. The

BOG comprised of a well balanced team of Consultants, Manufacturers & Users. This

time the BOG members are not only from Delhi but also from ASHRAE Sections of Jaipur,

Chandigarh & Kolkata. The complete roadmap for the year 2016-17 was presented during the

installation ceremony. The major events include –

• AIC TECH Flagship Event in November, 2016

• Participation in Technical Programs and conference like ACETECH Global Green Summit, Indian

Green Building Congress, International conference by Jamia Milia Islamia, ACREX etc.

• Addition of new student chapters

• Technical seminars and quiz contest at Colleges

• Job Fair for Students

Under Sustainable activity, a Solar Cold Store shall be installed, which has already been developed

and successfully tested at Delhi.

Small Group Knowledge Workshops on specific topics will be taken up on regular basis. The

trainers would be BOG members as well as outside faculty. Development of young members to take

on responsibility in future, will be a major stress area this year and we pledge to develop new

leaders for future. Efforts will be made to come out with more Technical Journals on HVAC. We will

coordinate with other ASHRAE chapters to work on development of ASHRAE activities as a whole in

India. This year we plan to organize ASHRAE meetings outside Delhi in places like Jaipur,

Chandigarh, Dehradun etc. A close coordination will be maintained with ISHRAE local chapters

and at National Level to successfully organize events jointly.

A major achievement for all ASHRAE Chapters in India has been the selection for AVRC's from

various chapters viz – Mr. G.C. Modgil – GGAC, ASHRAE India; Mr. V Krishnan – CTTC, ASHRAE

Mumbai; Mr. Yogesh Thakkar- Membership, ASHRAE Western India; Mr. G Ramesh – Research,

ASHRAE Bangalore.

Our pledge would be to have more members from various Chapters nominated to Society positions

to ASHRAE USA.

In order to make our newsletter more adaptive, we are inviting articles from other ASHRAE chapters

as well as other HVAC related associations. The class room education program started in the last

edition, is being continued in the present edition.

Regards,

K.K. MITRA

President - ASHRAE India Chapter

Chapter Activities

ASHRAE India Chapter organised a full Day

Technical Workshop on 17th June, 2016 at K-43,

(Basement ), Kailash Colony , New Delhi-

110048, The topics of presentation were 'Best

practices for operation and preventive

maintenance of HVAC systems in Green

Buildings' – By Dr. Rajinder Singh, 'Energy Saving

in Green Buildings by Insulation' – By Mr. K K

Mitra and 'Heat load Calculation' – By Mr. U S

Jadon. The event was appreciated by the

participants.

ASHRAE India Chapter organized a tour

programme at Manali from - 16th July 2016 to

19th July 2016. The event focused on technical

session, YEAs meet-up with lots of fun & activities.

In addition to this, a local sight-seen was

conducted.

The 8th Sustainable Energy & Environment Quiz

was successfully organized by Energy Club under

the aegis of Center for Energy & Environment on

20th & 21st August, 2016 at MNIT Jaipur. The

event was sponsored by ISHRAE and supported

by ASHRAE India Chapter. A total of 277 teams

from 13 different colleges across India had

registered for the quiz. On the first day, a play

titled 'Ummeed Nayi Subah Ki' was organized to

convey the message of Energy Conservation from

the Energy Club team in association with DIL

(Dramatics Society of MNIT).

Annual General Meeting and Installation Ceremony of AIC BOG 2016 – 2017The Annual General Meeting and Installation of the new BOG of AIC was held at The Theatre India Habitat Centre , Lodhi

Road , New Delhi on 8th July, 2016, The oath to the new team was given by Hon'ble Dr. Prem C. Jain .

Technical Workshop on 16th July.,2016

ASHRAE Distinguished Lecture

Technical Workshop on 17th June, 2016

ASHRAE India Chapter organised a Full Day Technical Workshop on 'UNDERSTANDING

REFRIGERANTS' by Mr. Kapil Singhal on 16th July.,2016 at Lodhi Road New Delhi , The event was

well attended. Mexichem, India was the partner for the event.

ASHRAE Distinguished Lecture Programme

was held at Poornima College of

Engineering, Jaipur by DL Speaker Dr . Om

Taneja on “Future is the Smart Cities” on 5th

August.,2016 at Jaipur. The workshop was

very well attended and appreciated by the

participation. The occasion witnessed the

presence of members from ASHRAE India and

Jaipur section along with the faculty members

of Mechanical Department, PCE. AIC BOG

meeting was also held with the Jaipur Section

members.

Mr. K K Mitra President

Mr. Priyank S. Garg President Elect.

Mr. Indrajit Bhattacharya Vice President

Dr. Rajinder Singh Imm. Past President.

Mr. Dharmendra Rathore Secretary

Mr. Uma Singh Jadon Treasurer

Dr. Varun Jain BOG Member

Mr. Abid Husain BOG Member

Mr. Sunil Bajaj BOG Member

Mr. Kanagraj Ganesan BOG Member

Mr. Manoj Chakravorti BOG Member

Mr. Pankaj Sareen BOG Member

Mr. Subhasish Dasgupta BOG Member (President Kolkata Section)

Mr. S.S.Gangwar BOG Member (President Jaipur Section)

Mr. Ashu Gupta BOG Member

Mr. Raju Bhat BOG Member

AIC BOG 16-17

Yea Programme at Manali

Quiz Programme

IAQA – India Chapter

The India Chapter of IAQA the first chapter ever, outside of

North America was launched on 26th of August, 2016 in Goa,

India. At the launch, an MOU was signed with ISHRAE(Indian

Society of Heating, Refrigerating& Air-conditioning Engineers)

for sharing of knowledge and connecting with concerned

industries. It was attended by about 150 delegates from all over

India. A committee has been formulated with Richie Mittal as

the Chapter Director and Viswanath Krishnan as Vice Chapter

Director.

The initiatives of the India Chapter are to develop the following

guidelines:

• Parameters of good indoor air quality

• Identificationan effective home air purifier

The newly formed committee will work towards dissemination of knowledge and actively involve

more organisations and people to improve air quality.

By Richie Mittal, Chapter Director – IAQA, India

Formation of IAQA – India Chapter -

Stephanie, Richie, Donald and Krishnan

ASHRAE India Chapters

coordination meeting was held

at the Bogmalo Beach Resort, Goa

on 27th Aug., 2016.

Workshop on Productivity in Green Buildings

“WORKSHOP ON PRODUCTIVITY IN GREEN

BUILDINGS” was organised by IGBC in Jaipur

under leadership of Dr Jyotirmay Mathur. The

event was supported by ASHRAE Jaipur section.

nfocusI www.ashraeindia.orgctivitiesA

• Mr. Sunil Gupta, Chair - CTTC • Mr. K.D.Singh, Chair - Research Promotion • Dr. Rajinder Singh, Chair- Student Activities • Mr. Dinesh Gupta,

Chair - GGAC • Mr. Indrajit Bhattacharya, Chair - Membership Promotion • Mr. Ashu Gupta, Chair-YEA

Chapter Activities

ASHRAE India Chapter organised a full Day

Technical Workshop on 17th June, 2016 at K-43,

(Basement ), Kailash Colony , New Delhi-

110048, The topics of presentation were 'Best

practices for operation and preventive

maintenance of HVAC systems in Green

Buildings' – By Dr. Rajinder Singh, 'Energy Saving

in Green Buildings by Insulation' – By Mr. K K

Mitra and 'Heat load Calculation' – By Mr. U S

Jadon. The event was appreciated by the

participants.

ASHRAE India Chapter organized a tour

programme at Manali from - 16th July 2016 to

19th July 2016. The event focused on technical

session, YEAs meet-up with lots of fun & activities.

In addition to this, a local sight-seen was

conducted.

The 8th Sustainable Energy & Environment Quiz

was successfully organized by Energy Club under

the aegis of Center for Energy & Environment on

20th & 21st August, 2016 at MNIT Jaipur. The

event was sponsored by ISHRAE and supported

by ASHRAE India Chapter. A total of 277 teams

from 13 different colleges across India had

registered for the quiz. On the first day, a play

titled 'Ummeed Nayi Subah Ki' was organized to

convey the message of Energy Conservation from

the Energy Club team in association with DIL

(Dramatics Society of MNIT).

Annual General Meeting and Installation Ceremony of AIC BOG 2016 – 2017The Annual General Meeting and Installation of the new BOG of AIC was held at The Theatre India Habitat Centre , Lodhi

Road , New Delhi on 8th July, 2016, The oath to the new team was given by Hon'ble Dr. Prem C. Jain .

Technical Workshop on 16th July.,2016

ASHRAE Distinguished Lecture

Technical Workshop on 17th June, 2016

ASHRAE India Chapter organised a Full Day Technical Workshop on 'UNDERSTANDING

REFRIGERANTS' by Mr. Kapil Singhal on 16th July.,2016 at Lodhi Road New Delhi , The event was

well attended. Mexichem, India was the partner for the event.

ASHRAE Distinguished Lecture Programme

was held at Poornima College of

Engineering, Jaipur by DL Speaker Dr . Om

Taneja on “Future is the Smart Cities” on 5th

August.,2016 at Jaipur. The workshop was

very well attended and appreciated by the

participation. The occasion witnessed the

presence of members from ASHRAE India and

Jaipur section along with the faculty members

of Mechanical Department, PCE. AIC BOG

meeting was also held with the Jaipur Section

members.

Mr. K K Mitra President

Mr. Priyank S. Garg President Elect.

Mr. Indrajit Bhattacharya Vice President

Dr. Rajinder Singh Imm. Past President.

Mr. Dharmendra Rathore Secretary

Mr. Uma Singh Jadon Treasurer

Dr. Varun Jain BOG Member

Mr. Abid Husain BOG Member

Mr. Sunil Bajaj BOG Member

Mr. Kanagraj Ganesan BOG Member

Mr. Manoj Chakravorti BOG Member

Mr. Pankaj Sareen BOG Member

Mr. Subhasish Dasgupta BOG Member (President Kolkata Section)

Mr. S.S.Gangwar BOG Member (President Jaipur Section)

Mr. Ashu Gupta BOG Member

Mr. Raju Bhat BOG Member

AIC BOG 16-17

Yea Programme at Manali

Quiz Programme

IAQA – India Chapter

The India Chapter of IAQA the first chapter ever, outside of

North America was launched on 26th of August, 2016 in Goa,

India. At the launch, an MOU was signed with ISHRAE(Indian

Society of Heating, Refrigerating& Air-conditioning Engineers)

for sharing of knowledge and connecting with concerned

industries. It was attended by about 150 delegates from all over

India. A committee has been formulated with Richie Mittal as

the Chapter Director and Viswanath Krishnan as Vice Chapter

Director.

The initiatives of the India Chapter are to develop the following

guidelines:

• Parameters of good indoor air quality

• Identificationan effective home air purifier

The newly formed committee will work towards dissemination of knowledge and actively involve

more organisations and people to improve air quality.

By Richie Mittal, Chapter Director – IAQA, India

Formation of IAQA – India Chapter -

Stephanie, Richie, Donald and Krishnan

ASHRAE India Chapters

coordination meeting was held

at the Bogmalo Beach Resort, Goa

on 27th Aug., 2016.

Workshop on Productivity in Green Buildings

“WORKSHOP ON PRODUCTIVITY IN GREEN

BUILDINGS” was organised by IGBC in Jaipur

under leadership of Dr Jyotirmay Mathur. The

event was supported by ASHRAE Jaipur section.

nfocusI www.ashraeindia.orgctivitiesA

• Mr. Sunil Gupta, Chair - CTTC • Mr. K.D.Singh, Chair - Research Promotion • Dr. Rajinder Singh, Chair- Student Activities • Mr. Dinesh Gupta,

Chair - GGAC • Mr. Indrajit Bhattacharya, Chair - Membership Promotion • Mr. Ashu Gupta, Chair-YEA

www.ashraeindia.org

directly while an AC compressor requires a power inverter. DC

compressor provides a "soft-start" which means that the typical

startup surge of an AC compressor running on an inverter is

eliminated. A normal AC compressor will draw up to 500% more

amps on startup, meaning that while running on an inverter, the

inverter must be oversized accordingly. Oversized inverters are

much less efficient. The DC compressor not only avoids needing an

inverter, they also minimize the surge or spike at time of startup.

Energy usage reduction through improved efficiency and use of

renewable energy employing variable speed DC compressors is an

advantage of such systems.

R134a is being utilized in the domestic refrigerators, which solves

the problem of Ozone Depletion Potential (ODP) but not Global

Warming Potential (GWP). It has zero ODP but GDP100 of 1300.

Similarly, R22 is going to be phased out. R290 (Propane) is natural

refrigerant which may be one of the possible solution of ODP and

GWP. R290 has zero ODP & 3 GWP100 and excellent

thermodynamic properties. It has -42.10C boiling point and

96.70C critical temperature. It is compatible with mineral oil. Latent

heat of vaporization of R290 is 424.19 kJ/kg and zero temperature

glide but the most important concern is its flammability. It comes

under A3 safety group. It should be taken into notice that millions of

tons of hydrocarbon are used safely every year throughout the

globe. R290 can also be used safely in refrigerator as it uses small

quantity of charge around 100-125 grams. Proper safety measures

can solves the problem of flammability.

This solar refrigerator is based on variable refrigerant flow (VRF)

system. VRF system is a refrigerant system that varies the refrigerant

flow rate with the help of the variable speed compressor and the

electronic expansion valve. In this system, the compressor frequency

and the electronic expansion valve opening is controlled

simultaneously.

In conclusion, this solar refrigerator can solve the problem of

spoilage of milk and the same can be preserved for a long time.

It is not dependent upon grid connection and fossil fuels. Solar

energy is easily available in most of the parts of India. Milk

refrigerator is utilizing the eco-friendly refrigerant. It not only

promotes the renewable energy but also use of R290 solving the

problems of Ozone Layer Depletion and Global Warming. DC

variable speed compressor compatible with R290 refrigerant will be

utilizing in this refrigerator. DC compressor has soft start and do not

require power invertor. A VRF operation further improves its

performance.

India is the world's one of the largest producer of milk. It claims

20% of the world's total milk production. The milk preservation is a

fast growing business in developing countries. High-energy cost and

environmental concerns are two major issues in using the

conventional energy sources. Besides, all the villages are not

connected to the grid that's why refrigeration facility is not available.

If the milk is exposed to high temperature for several hours, it will

cause bacteria reproduction. Milk should be kept at a lower

temperature to prevent bacteria reproduction and follow the

permissible limit of bacteria content. At present, almost all dairy

operations are performed using grid supply with the diesel generator

as backup. If a village is not connected to the grid, then, it is difficult

to preserve the milk.

The village level co-operative societies for milk collections are

provided by bulk milk coolers operating on conventional grid supply

of electricity and in the case of unavailability of electric supply diesel

generator sets are provided for cooling the milk. The problem of

electricity and diesel generator sets can be solved by refrigeration

system for cooling the milk based on renewable energy at society

level.

Milk Refrigerator using renewable energy may be one of the

solutions to provide the refrigeration facility to rural areas. Solar

energy can be used in either Vapor Absorption System or Vapor

Compression Refrigeration System. Various solar operated vapor

absorption systems are already reported and derelict the vapor

compression system. Vapor compression system can be directly run

by solar photovoltaic systems. It is simple in construction and has

high power to weight ratio. It has no moving parts and simple to

install. Photovoltaic array should produce sufficient power to run

the refrigerator, as ample amount of solar irradiances are available

in India. Studies reveal that solar PV should be designed by three

times that of refrigerator load power. Crystalline silicon photovoltaic

cell has high conversion efficiency from solar irradiance to

electricity. It is a stand-alone solar photovoltaic system therefore;

lead acid batteries with charge controller will be utilized.

It is feasible to use the solar energy for Milk Refrigerator based on

vapor compression system. In the case of refrigeration system, two

different options for powering the compressor are either AC or DC.

An AC current compressor is driven by alternative voltage such as

120 or 220 V and 50 Hz. On the other hand, DC compressor needs

low voltage and direct current supply of 12-24 V. Even though, DC

compressor has similar type of mechanical compression element

with AC compressor, it has a brushless electrical motor. Renewable

energy technologies can be used to control a DC compressor

Solar Milk Refrigerator

Dr. Shishir Chand BhaduriProf, Dept of Mech EnggJK Lakshmipat University, Jaipur

Mr. Shailendra KaseraHOD, Dept of Mech Engg

Poornima College of Engineering, Jaipur

Buildings are large consumers of energy in

all countries. In harsh climatic conditions, a

substantial share of energy goes to the air-

conditioning of buildings. This air-

conditioning load can be reduced through

many means; notable among them is the

proper design and selection of building

envelope and its components.

The use of thermal insulation in building

walls and roof does not only contribute in

reducing the required air-conditioning

system size but also in reducing the annual

energy cost. Additionally, it helps in

extending the periods of thermal comfort

without reliance on mechanical air-

conditioning especially during interseasons

periods. Therefore, proper use of thermal

insulation in buildings enhances thermal

comfort at less operating cost. However, the

magnitude of energy savings as a result of

using thermal insulation vary according to

the building type, the climatic conditions at

which the building is located as well as the

type, thickness, and location of the insulating

material used. The question now is no longer

should insulation be used but rather which

type and how much.

Thermal insulation is an important

technology to reduce energy consumption in

buildings by preventing heat gain/loss

through the building envelope. Thermal

insulation is a construction material with low

thermal conductivity, often less than

0.1W/mK. These materials have no other

purpose than to save energy and protect and

provide comfort to occupants. Of the many

forms, shapes and applications of thermal

insulation, this section focuses on those that

are commonly used for building envelopes–

i.e., walls and roof

Building insulation products are largely

classified into two groups – mineral fibre,

cellular plastic .

Mineral fibre products include rock

wool, slag wool and glass wool. These

materials are melted at high temperatures,

spun into fibre and then have a binding agent

added to form rigid sheets and insulation

batts. If removed in appropriate conditions,

mineral fibre can be reused and recycled at

the end of its life.

Cellular plastic products are oil-derived

and include rigid polyurethane, phenolic,

expanded polystyrene, and extruded

polystyrene. The products are available as

loose fill, rigid sheets and foam. Cellular

plastic products can be recycled. It is more

suitable for cellular plastic products to be

incinerated for energy recovery at their end of

life.

Building envelope thermal insulation is a

proven technology that contribute to energy

efficient buildings.

Feasibility of technology and

operational necessities :

In India, Energy Conservation building code

include requirements to safeguard minimum

acceptable insulation levels for building

envelopes, and thus provide the opportunity

for deploying the application of thermal

insulation technologies. Therefore, a critical

factor leading to large scale implementation

of thermal insulation in India is to put in place

supporting policies, both incentive and

mandatory measures.

The application requirements of most

building envelope thermal insulation products

include appropriate detailed design, good

workmanship and appropriate product

selection, handling and installation methods.

Therefore, capacity building, such as workshops

to train design professionals and construction

work forces in these areas are required.

Building envelope thermal insulation

products are used in association with the

construction details of floors, walls and

roofs/ceilings for new building constructions

and for retrofitting existing buildings.

Good detailing and workmanship to

prevent air leakage are crucial for all types of

building envelope thermal insulation. It is

important to pay additional attention to detail,

when installing insulation materials at the

electrical outlets and wiring inside walls,

cutting and shaping the insulation materials to

tightly enclose with the wall frame.

Furthermore, as an overall quality control

measure for building in extreme climatic

conditions, it is recommended to have

building envelope commissioning with

attention paid to thermal insulation, especially

in larger-scale buildings.

How the technology could contribute

to socio-economic development and

environmental protection :

The primary contribution of building

envelope thermal insulation is to provide

thermal comfort to its occupants. This supports

healthy living environments and better

productivity at workplaces.

Thermal insulation reduces unwanted heat

loss or heat gain through a building envelope.

This, in turn, reduces energy demand for

cooling and heating of buildings, and thus is a

mitigation measure to reduce GHG

emissions.

Financial requirements and costs :

Financial requirement for building envelope

thermal insulation includes the costs of the

products and their installation.

Thermal Insulation of Buildings

The objective of this image is to address the

impact of building envelope, effectiveness of

thermal performance of buildings in hot/

composite climates. It emphasizes the role of

insulation in achieving the desired objectives

of reduction in heat flow through roof

and wall.

The product and installation costs of

thermal insulation are computed based on per

unit of area and per unit of thermal

conductivity value. Maintenance costs for

thermal insulation products is low and not

even required for cellular plastic products. In

the case of mineral fibre , if the products

do not perform as expected due to

increased thermal conductivity caused by

moisture or vermin infestation, replacement

is required.

For naturally-ventilated buildings in mild

climatic conditions, roof insulation and west-

facing wall insulation are the most effective

methods of preventing heat gain through the

building envelope, and thus have better return

on investment compared to applying

insulation to the entire building envelope.

Cellular plastic products are rigid, stable

and performed well in the long term. They

require the least maintenance cost.

Advantages of thermal insulation:

• Reduction of energy consumption for

heating (by 30 % at least),

• Creation of a thermal comfort by

increasing the surface temperature of the

inside walls, Leaking elimination,

• Reduction of thermal stress of the

framework,

• Building lifetime prolongation,

• Improvement of the architectural look of

the building

lassroomCrticleA

By Dr. Sunil BajajISOFOAM -INDIAAIC BOG Member

www.ashraeindia.org

directly while an AC compressor requires a power inverter. DC

compressor provides a "soft-start" which means that the typical

startup surge of an AC compressor running on an inverter is

eliminated. A normal AC compressor will draw up to 500% more

amps on startup, meaning that while running on an inverter, the

inverter must be oversized accordingly. Oversized inverters are

much less efficient. The DC compressor not only avoids needing an

inverter, they also minimize the surge or spike at time of startup.

Energy usage reduction through improved efficiency and use of

renewable energy employing variable speed DC compressors is an

advantage of such systems.

R134a is being utilized in the domestic refrigerators, which solves

the problem of Ozone Depletion Potential (ODP) but not Global

Warming Potential (GWP). It has zero ODP but GDP100 of 1300.

Similarly, R22 is going to be phased out. R290 (Propane) is natural

refrigerant which may be one of the possible solution of ODP and

GWP. R290 has zero ODP & 3 GWP100 and excellent

thermodynamic properties. It has -42.10C boiling point and

96.70C critical temperature. It is compatible with mineral oil. Latent

heat of vaporization of R290 is 424.19 kJ/kg and zero temperature

glide but the most important concern is its flammability. It comes

under A3 safety group. It should be taken into notice that millions of

tons of hydrocarbon are used safely every year throughout the

globe. R290 can also be used safely in refrigerator as it uses small

quantity of charge around 100-125 grams. Proper safety measures

can solves the problem of flammability.

This solar refrigerator is based on variable refrigerant flow (VRF)

system. VRF system is a refrigerant system that varies the refrigerant

flow rate with the help of the variable speed compressor and the

electronic expansion valve. In this system, the compressor frequency

and the electronic expansion valve opening is controlled

simultaneously.

In conclusion, this solar refrigerator can solve the problem of

spoilage of milk and the same can be preserved for a long time.

It is not dependent upon grid connection and fossil fuels. Solar

energy is easily available in most of the parts of India. Milk

refrigerator is utilizing the eco-friendly refrigerant. It not only

promotes the renewable energy but also use of R290 solving the

problems of Ozone Layer Depletion and Global Warming. DC

variable speed compressor compatible with R290 refrigerant will be

utilizing in this refrigerator. DC compressor has soft start and do not

require power invertor. A VRF operation further improves its

performance.

India is the world's one of the largest producer of milk. It claims

20% of the world's total milk production. The milk preservation is a

fast growing business in developing countries. High-energy cost and

environmental concerns are two major issues in using the

conventional energy sources. Besides, all the villages are not

connected to the grid that's why refrigeration facility is not available.

If the milk is exposed to high temperature for several hours, it will

cause bacteria reproduction. Milk should be kept at a lower

temperature to prevent bacteria reproduction and follow the

permissible limit of bacteria content. At present, almost all dairy

operations are performed using grid supply with the diesel generator

as backup. If a village is not connected to the grid, then, it is difficult

to preserve the milk.

The village level co-operative societies for milk collections are

provided by bulk milk coolers operating on conventional grid supply

of electricity and in the case of unavailability of electric supply diesel

generator sets are provided for cooling the milk. The problem of

electricity and diesel generator sets can be solved by refrigeration

system for cooling the milk based on renewable energy at society

level.

Milk Refrigerator using renewable energy may be one of the

solutions to provide the refrigeration facility to rural areas. Solar

energy can be used in either Vapor Absorption System or Vapor

Compression Refrigeration System. Various solar operated vapor

absorption systems are already reported and derelict the vapor

compression system. Vapor compression system can be directly run

by solar photovoltaic systems. It is simple in construction and has

high power to weight ratio. It has no moving parts and simple to

install. Photovoltaic array should produce sufficient power to run

the refrigerator, as ample amount of solar irradiances are available

in India. Studies reveal that solar PV should be designed by three

times that of refrigerator load power. Crystalline silicon photovoltaic

cell has high conversion efficiency from solar irradiance to

electricity. It is a stand-alone solar photovoltaic system therefore;

lead acid batteries with charge controller will be utilized.

It is feasible to use the solar energy for Milk Refrigerator based on

vapor compression system. In the case of refrigeration system, two

different options for powering the compressor are either AC or DC.

An AC current compressor is driven by alternative voltage such as

120 or 220 V and 50 Hz. On the other hand, DC compressor needs

low voltage and direct current supply of 12-24 V. Even though, DC

compressor has similar type of mechanical compression element

with AC compressor, it has a brushless electrical motor. Renewable

energy technologies can be used to control a DC compressor

Solar Milk Refrigerator

Dr. Shishir Chand BhaduriProf, Dept of Mech EnggJK Lakshmipat University, Jaipur

Mr. Shailendra KaseraHOD, Dept of Mech Engg

Poornima College of Engineering, Jaipur

Buildings are large consumers of energy in

all countries. In harsh climatic conditions, a

substantial share of energy goes to the air-

conditioning of buildings. This air-

conditioning load can be reduced through

many means; notable among them is the

proper design and selection of building

envelope and its components.

The use of thermal insulation in building

walls and roof does not only contribute in

reducing the required air-conditioning

system size but also in reducing the annual

energy cost. Additionally, it helps in

extending the periods of thermal comfort

without reliance on mechanical air-

conditioning especially during interseasons

periods. Therefore, proper use of thermal

insulation in buildings enhances thermal

comfort at less operating cost. However, the

magnitude of energy savings as a result of

using thermal insulation vary according to

the building type, the climatic conditions at

which the building is located as well as the

type, thickness, and location of the insulating

material used. The question now is no longer

should insulation be used but rather which

type and how much.

Thermal insulation is an important

technology to reduce energy consumption in

buildings by preventing heat gain/loss

through the building envelope. Thermal

insulation is a construction material with low

thermal conductivity, often less than

0.1W/mK. These materials have no other

purpose than to save energy and protect and

provide comfort to occupants. Of the many

forms, shapes and applications of thermal

insulation, this section focuses on those that

are commonly used for building envelopes–

i.e., walls and roof

Building insulation products are largely

classified into two groups – mineral fibre,

cellular plastic .

Mineral fibre products include rock

wool, slag wool and glass wool. These

materials are melted at high temperatures,

spun into fibre and then have a binding agent

added to form rigid sheets and insulation

batts. If removed in appropriate conditions,

mineral fibre can be reused and recycled at

the end of its life.

Cellular plastic products are oil-derived

and include rigid polyurethane, phenolic,

expanded polystyrene, and extruded

polystyrene. The products are available as

loose fill, rigid sheets and foam. Cellular

plastic products can be recycled. It is more

suitable for cellular plastic products to be

incinerated for energy recovery at their end of

life.

Building envelope thermal insulation is a

proven technology that contribute to energy

efficient buildings.

Feasibility of technology and

operational necessities :

In India, Energy Conservation building code

include requirements to safeguard minimum

acceptable insulation levels for building

envelopes, and thus provide the opportunity

for deploying the application of thermal

insulation technologies. Therefore, a critical

factor leading to large scale implementation

of thermal insulation in India is to put in place

supporting policies, both incentive and

mandatory measures.

The application requirements of most

building envelope thermal insulation products

include appropriate detailed design, good

workmanship and appropriate product

selection, handling and installation methods.

Therefore, capacity building, such as workshops

to train design professionals and construction

work forces in these areas are required.

Building envelope thermal insulation

products are used in association with the

construction details of floors, walls and

roofs/ceilings for new building constructions

and for retrofitting existing buildings.

Good detailing and workmanship to

prevent air leakage are crucial for all types of

building envelope thermal insulation. It is

important to pay additional attention to detail,

when installing insulation materials at the

electrical outlets and wiring inside walls,

cutting and shaping the insulation materials to

tightly enclose with the wall frame.

Furthermore, as an overall quality control

measure for building in extreme climatic

conditions, it is recommended to have

building envelope commissioning with

attention paid to thermal insulation, especially

in larger-scale buildings.

How the technology could contribute

to socio-economic development and

environmental protection :

The primary contribution of building

envelope thermal insulation is to provide

thermal comfort to its occupants. This supports

healthy living environments and better

productivity at workplaces.

Thermal insulation reduces unwanted heat

loss or heat gain through a building envelope.

This, in turn, reduces energy demand for

cooling and heating of buildings, and thus is a

mitigation measure to reduce GHG

emissions.

Financial requirements and costs :

Financial requirement for building envelope

thermal insulation includes the costs of the

products and their installation.

Thermal Insulation of Buildings

The objective of this image is to address the

impact of building envelope, effectiveness of

thermal performance of buildings in hot/

composite climates. It emphasizes the role of

insulation in achieving the desired objectives

of reduction in heat flow through roof

and wall.

The product and installation costs of

thermal insulation are computed based on per

unit of area and per unit of thermal

conductivity value. Maintenance costs for

thermal insulation products is low and not

even required for cellular plastic products. In

the case of mineral fibre , if the products

do not perform as expected due to

increased thermal conductivity caused by

moisture or vermin infestation, replacement

is required.

For naturally-ventilated buildings in mild

climatic conditions, roof insulation and west-

facing wall insulation are the most effective

methods of preventing heat gain through the

building envelope, and thus have better return

on investment compared to applying

insulation to the entire building envelope.

Cellular plastic products are rigid, stable

and performed well in the long term. They

require the least maintenance cost.

Advantages of thermal insulation:

• Reduction of energy consumption for

heating (by 30 % at least),

• Creation of a thermal comfort by

increasing the surface temperature of the

inside walls, Leaking elimination,

• Reduction of thermal stress of the

framework,

• Building lifetime prolongation,

• Improvement of the architectural look of

the building

lassroomCrticleA

By Dr. Sunil BajajISOFOAM -INDIAAIC BOG Member

Refrigeration and Vapour Compression Refrigeration System (Cycle) for Refrigeration and Air-conditioning Engineers

liquid refrigerant enters the throttle device (expansion device or metering device) having narrow opening, expansion of refrigerant will takes place; pressure of the refrigerant is reduced. We get the cooling effect, after throttling the low temperature refrigerant is a mixture of liquid and the vapour part depend upon the pressure drop in throttling device, if pressure drop in more, more friction, more vapour formation. This low temperature refrigerant enters the evaporator and abstracting the heat from the food stuffs preserved in case of refrigeration or abstracting the heat from the space to be air-conditioned, evaporation of refrigerant will takes places, then again these low temperature low pressure refrigerant vapors sucked by the compressor. This cycle repeats again and again. This is known as vapour compression refrigeration cycle (system).

1.5 COEFFICIENT OF PERFORMANCE (COP) OF VAPOUR COMPRESSION REFRIGERATION SYSTEM

Coefficient of Performance of vapor-compression refrigeration system is defined as the ratio of net refrigerating effect to the compressor work.

Coefficient of = Net refrigerating effect /performance (COP) Compressor work = N / W

Net refrigerating effect (N) = m (h – h )1 4

Compressor Work (W) = m (h – h )2 1

Where (m) = mass flow rate of refrigerant

h1 = specific enthalpy at compressor suction

h2 = specific enthalpy at compressor discharge

h3 = specific enthalpy at condenser outlet

h4 = specific enthalpy after expansion

1.6 ACTUAL VAPOUR COMPRESSION REFRIGERATION SYSTEM (CYCLE)

An actual vapor-compression refrigeration cycle involves irreversibilities in various components - mainly due to fluid friction (causes pressure drops) and heat transfer to or from the surroundings. As a result, the COP decreases.

Differences

• Non-isentropic compression;

• Superheated vapor at evaporator exit;

• Sub-cooled liquid at condenser exit;

• Pressure drops in condenser and evaporator.

In actual vapor-compression refrigeration cycle there is pressure drop in suction vapour in flowing through the suction line from evaporator to compressor inlet. Refrigerant vapours from evaporator flowing through suction valve, suction valve offers resistance, bulk volume of vapours is drawn through narrow opening of suction valve, there is wire drawing effect, its effect is pressure drop.

Suction is at low temperature and discharge of refrigerant is at high temperature, due to that cylinder walls are at high temperature. Hence there is heat transfer is from cylinder walls to suction, due to that there is increase in enthalpy.

During compression, the temperature and pressure of the vapour refrigerant is increased. There is heat transfer from refrigerant to cylinder walls; hence there is increase in enthalpy. There is wire drawing effect during the passage of vapour refrigerant through discharge valve, its effect is pressure drop.

There is pressure drop in discharge line because of frictional resistance to flow of refrigerant due to roughness of pipe. There is also pressure drop in condenser due to frictional resistance to flow of refrigerant. In liquid line there is also pressure drop due to frictional resistance to flow of refrigerant.

In evaporator, there is pressure drop due to frictional resistance to flow of refrigerant. On changing from liquid to vapour, velocity of refrigerant is increased; its effect is pressure drop.

1.1 REFRIGERATION

Refrigeration means production of cold and coldness is produced by abstraction (removal) of heat. Refrigeration is a process of moving heat from one location to another in controlled conditions. The work of heat transport is traditionally driven by mechanical work, but can also be driven by heat, magnetism, electricity, or other means.

1.2 VAPOUR COMPRESSION REFRIGERATION SYSTEM (VAPOUR COMPRESSION CYCLE)

Vapor compression refrigeration system is the most widely used method for refrigeration used in domestic and commercial refrigerators, water coolers, large-scale warehouses for chilled or frozen storage of foods, ice plants, refrigerated trucks and refrigeration in oil refineries, petrochemical and chemical processing plants, natural gas processing plants etc. This system is used for air-conditioning of buildings like shopping malls, offices, hospitals, schools and colleges etc. This system is used for air-conditioning of cars, buses and rail etc.

1.3 DESCRIPTION OF VAPOUR COMPRESSION REFRIGERATION SYSTEM (VAPOUR COMPRESSION CYCLE)

The vapor-compression refrigeration system has four major components: evaporator, compressor, condenser, and expansion (or throttle) device. The most widely used refrigeration cycle is the vapor-compression refriger¬ation cycle. In an ideal vapor-compression refrigeration cycle, the refrigerant enters the compressor as a saturated vapor and is cooled to the saturated liquid state in the condenser. It is then throttled to the evaporator pressure and vaporizes as it absorbs heat from the refrigerated space.

The ideal vapor-compression refrigeration cycle consists of four processes.

Process Description

1-2 Isentropic compression

2-3 Constant temperature heat rejection in the condenser

3-4 Throttling in a throttle device (expansion device)

4-1 Constant temperature heat abstraction (addition) in the evaporator

The ideal vapor-compression refrigeration cycle is shown on the Pressure-Enthalpy (P-h) diagram (Fig. 1.3).

Thus the refrigeration cycle comprises of:

(1) Absorption of heat from the substance to be cooled by the evaporation of a liquid refrigerant in the evaporator at a controlled lower pressure.

(2) Raising the pressure (to raise the condensing temperature) of the low pressure vapour coming from the evaporator, by the use of the compressor.

(3) Removal /rejection of heat from the high-pressure vapour in the condenser so as to liquefy or condense the vapour.

(4) By the use of the throttling device, reducing the pressure of the high-pressure liquid (from the condenser) to the level of pres¬sure needed in the evaporator.

These components are inter-connected by pipes-such a, evaporator to compressor by the suction line, compressor to condenser by the discharge or hot gas line and from condenser to throt¬tling device by the liquid line. In addition to raising the pressure of the vapour, the compressor also creates the pressure difference between the evaporator and condenser and thus maintain a continuous flow of the refrig¬erant through the system.

1.4 WORKING OF VAPOUR COMPRESSION REFRIGERATION SYSTEM

Vapor-compression refrigeration system is a closed thermodynamic system and the working fluid used in this closed system is known as refrigerant. In this system compressor sucks low temperature low pressure refrigerant vapors from the evaporator and compresses to high temperature high pressure refrigerant vapors by application of work, after compression the refrigerant vapors are superheated. These high temperature high pressure superheated refrigerant vapors goes to the condenser, firstly these refrigerant vapors are desuperheated and then condensed to liquid refrigerant by rejecting latent heat to the atmosphere in case of air cooled condensers and rejecting the heat to cooling water in case of water cooled condensers, using cooling towers.

In rare cases the liquid refrigerant is sub-cooled in the condenser if the cooling water inlet temperature to condenser is lower or the flow rate of cooling water is higher. Sub-cooling is always advantageous. From condenser, the high-pressure

Fig.1.2 Ideal vapor-compression cycle

Fig.1.1 Refrigeration

Fig.1.3 Ideal vapor-compression cycle on the Pressure-Enthalpy (P-h) diagram

Fig.1.5 Coefficient of performance of vapor-compression refrigeration system

Dr. Rajinder Singh

Senior Faculty, Pusa Institute of Technology,

(Imm. Past President-ASHRAE India Chapter)

lassroomC www.ashraeindia.orglassroomC

Fig.1.4 Working of vapor-compression refrigeration system

Fig.1.6 Actual vapor-compression refrigeration system

Refrigeration and Vapour Compression Refrigeration System (Cycle) for Refrigeration and Air-conditioning Engineers

liquid refrigerant enters the throttle device (expansion device or metering device) having narrow opening, expansion of refrigerant will takes place; pressure of the refrigerant is reduced. We get the cooling effect, after throttling the low temperature refrigerant is a mixture of liquid and the vapour part depend upon the pressure drop in throttling device, if pressure drop in more, more friction, more vapour formation. This low temperature refrigerant enters the evaporator and abstracting the heat from the food stuffs preserved in case of refrigeration or abstracting the heat from the space to be air-conditioned, evaporation of refrigerant will takes places, then again these low temperature low pressure refrigerant vapors sucked by the compressor. This cycle repeats again and again. This is known as vapour compression refrigeration cycle (system).

1.5 COEFFICIENT OF PERFORMANCE (COP) OF VAPOUR COMPRESSION REFRIGERATION SYSTEM

Coefficient of Performance of vapor-compression refrigeration system is defined as the ratio of net refrigerating effect to the compressor work.

Coefficient of = Net refrigerating effect /performance (COP) Compressor work = N / W

Net refrigerating effect (N) = m (h – h )1 4

Compressor Work (W) = m (h – h )2 1

Where (m) = mass flow rate of refrigerant

h1 = specific enthalpy at compressor suction

h2 = specific enthalpy at compressor discharge

h3 = specific enthalpy at condenser outlet

h4 = specific enthalpy after expansion

1.6 ACTUAL VAPOUR COMPRESSION REFRIGERATION SYSTEM (CYCLE)

An actual vapor-compression refrigeration cycle involves irreversibilities in various components - mainly due to fluid friction (causes pressure drops) and heat transfer to or from the surroundings. As a result, the COP decreases.

Differences

• Non-isentropic compression;

• Superheated vapor at evaporator exit;

• Sub-cooled liquid at condenser exit;

• Pressure drops in condenser and evaporator.

In actual vapor-compression refrigeration cycle there is pressure drop in suction vapour in flowing through the suction line from evaporator to compressor inlet. Refrigerant vapours from evaporator flowing through suction valve, suction valve offers resistance, bulk volume of vapours is drawn through narrow opening of suction valve, there is wire drawing effect, its effect is pressure drop.

Suction is at low temperature and discharge of refrigerant is at high temperature, due to that cylinder walls are at high temperature. Hence there is heat transfer is from cylinder walls to suction, due to that there is increase in enthalpy.

During compression, the temperature and pressure of the vapour refrigerant is increased. There is heat transfer from refrigerant to cylinder walls; hence there is increase in enthalpy. There is wire drawing effect during the passage of vapour refrigerant through discharge valve, its effect is pressure drop.

There is pressure drop in discharge line because of frictional resistance to flow of refrigerant due to roughness of pipe. There is also pressure drop in condenser due to frictional resistance to flow of refrigerant. In liquid line there is also pressure drop due to frictional resistance to flow of refrigerant.

In evaporator, there is pressure drop due to frictional resistance to flow of refrigerant. On changing from liquid to vapour, velocity of refrigerant is increased; its effect is pressure drop.

1.1 REFRIGERATION

Refrigeration means production of cold and coldness is produced by abstraction (removal) of heat. Refrigeration is a process of moving heat from one location to another in controlled conditions. The work of heat transport is traditionally driven by mechanical work, but can also be driven by heat, magnetism, electricity, or other means.

1.2 VAPOUR COMPRESSION REFRIGERATION SYSTEM (VAPOUR COMPRESSION CYCLE)

Vapor compression refrigeration system is the most widely used method for refrigeration used in domestic and commercial refrigerators, water coolers, large-scale warehouses for chilled or frozen storage of foods, ice plants, refrigerated trucks and refrigeration in oil refineries, petrochemical and chemical processing plants, natural gas processing plants etc. This system is used for air-conditioning of buildings like shopping malls, offices, hospitals, schools and colleges etc. This system is used for air-conditioning of cars, buses and rail etc.

1.3 DESCRIPTION OF VAPOUR COMPRESSION REFRIGERATION SYSTEM (VAPOUR COMPRESSION CYCLE)

The vapor-compression refrigeration system has four major components: evaporator, compressor, condenser, and expansion (or throttle) device. The most widely used refrigeration cycle is the vapor-compression refriger¬ation cycle. In an ideal vapor-compression refrigeration cycle, the refrigerant enters the compressor as a saturated vapor and is cooled to the saturated liquid state in the condenser. It is then throttled to the evaporator pressure and vaporizes as it absorbs heat from the refrigerated space.

The ideal vapor-compression refrigeration cycle consists of four processes.

Process Description

1-2 Isentropic compression

2-3 Constant temperature heat rejection in the condenser

3-4 Throttling in a throttle device (expansion device)

4-1 Constant temperature heat abstraction (addition) in the evaporator

The ideal vapor-compression refrigeration cycle is shown on the Pressure-Enthalpy (P-h) diagram (Fig. 1.3).

Thus the refrigeration cycle comprises of:

(1) Absorption of heat from the substance to be cooled by the evaporation of a liquid refrigerant in the evaporator at a controlled lower pressure.

(2) Raising the pressure (to raise the condensing temperature) of the low pressure vapour coming from the evaporator, by the use of the compressor.

(3) Removal /rejection of heat from the high-pressure vapour in the condenser so as to liquefy or condense the vapour.

(4) By the use of the throttling device, reducing the pressure of the high-pressure liquid (from the condenser) to the level of pres¬sure needed in the evaporator.

These components are inter-connected by pipes-such a, evaporator to compressor by the suction line, compressor to condenser by the discharge or hot gas line and from condenser to throt¬tling device by the liquid line. In addition to raising the pressure of the vapour, the compressor also creates the pressure difference between the evaporator and condenser and thus maintain a continuous flow of the refrig¬erant through the system.

1.4 WORKING OF VAPOUR COMPRESSION REFRIGERATION SYSTEM

Vapor-compression refrigeration system is a closed thermodynamic system and the working fluid used in this closed system is known as refrigerant. In this system compressor sucks low temperature low pressure refrigerant vapors from the evaporator and compresses to high temperature high pressure refrigerant vapors by application of work, after compression the refrigerant vapors are superheated. These high temperature high pressure superheated refrigerant vapors goes to the condenser, firstly these refrigerant vapors are desuperheated and then condensed to liquid refrigerant by rejecting latent heat to the atmosphere in case of air cooled condensers and rejecting the heat to cooling water in case of water cooled condensers, using cooling towers.

In rare cases the liquid refrigerant is sub-cooled in the condenser if the cooling water inlet temperature to condenser is lower or the flow rate of cooling water is higher. Sub-cooling is always advantageous. From condenser, the high-pressure

Fig.1.2 Ideal vapor-compression cycle

Fig.1.1 Refrigeration

Fig.1.3 Ideal vapor-compression cycle on the Pressure-Enthalpy (P-h) diagram

Fig.1.5 Coefficient of performance of vapor-compression refrigeration system

Dr. Rajinder Singh

Senior Faculty, Pusa Institute of Technology,

(Imm. Past President-ASHRAE India Chapter)

lassroomC www.ashraeindia.orglassroomC

Fig.1.4 Working of vapor-compression refrigeration system

Fig.1.6 Actual vapor-compression refrigeration system