various applications of fluid mechanics

7/23/2019 Various Applications of Fluid Mechanics

1/10

University Of Mauritius

BEng (Hons) Chemical and Environmental Engineering - E400

FLUID MECHANICS-CHE2001Y

Assignment 1: Latest applications of Fluid Mechanics in Domestic,

Agricultural, Commercial and Industrial sectors.

Name: Fanilo Antra Tia Razafindralambo


2/10

1. Table of Contents

1.

Table of Contents ................................................................................................ 2

2. Introduction ......................................................................................................... 3

3.

Domestic applications ......................................................................................... 4

Bladeless fan .............................................................................................................................. 4

Silicon Gas turbine .................................................................................................................... 4

4.

Commercial applications ..................................................................................... 5

Transport Means ....................................................................................................................... 5

Mp3 players ............................................................................................................................... 5

Fluid Lenses ............................................................................................................................... 6

Smart fluids ............................................................................................................................... 6

Falkirk wheel ............................................................................................................................. 7

5.

Agricultural applications ..................................................................................... 7

Study of the atmosphere and oceans ....................................................................................... 7

6.

Industrial applications ......................................................................................... 8

Computational Fluid Dynamics (CFD) ................................................................................... 8

Lubricants .................................................................................................................................. 8

Exploitation of wind energy ..................................................................................................... 8

7.

Bibliography ........................................................................................................ 9


3/10

2. Introduction

Fluid Mechanicsalong with Thermodynamicsare probably the most important fields in which

a chemical engineer should excel. The two subjects offer a broad understanding of fluids which

allows the engineer to design and control processes effectively.

Fluid dynamics forms part of our daily lives in many simple processes ranging from the action of

watering with the aid of a hose to complex tasks such as the design of hydraulic systems.

It has traditionally been applied in such areas as the design of canal, levee, and dam systems; the

design of pumps, compressors, and piping and ducting used in the water and air conditioning

systems of homes and businesses, as well as the piping systems needed in chemical plants; the

aerodynamics of automobiles and sub- and supersonic airplanes; and the development of many

different flow measurement devices such as gas pump meters.

In this document, applications of fluid mechanics in domestic, industrial, commercial and

agricultural areas will be enumerated and described from an engineering perspective briefly.


4/10

3. Domestic applications

Bladeless fan

They were first released in early 2009 by Sir James

Dysons company. The functioning, which is rather

simple, of the fan is absolutely a marvel of fluid

mechanics. Basically, Air comes in through the pedestal

and moves up through the circular tube that functions like

a ramp, forcing the air forward. And the resulting air flow

is buffeting free, which means that it is greener that the

normal fan. It is also much less noisy than the formal one.

(Nicholson, 2013)

Silicon Gas turbine

Alan Epstein, a professor of aeronautics and

astronautics at the Massachusetts Institute of

Technology, and his team have done a lot of

research on tiny gas turbine engines made ofsilicon. ProfessorEpsteindiscovered that the

basic concepts of turbine theory apply even to his

microturbines; the fluid mechanics turns out to be

the same as that for larger engines, as long as the

passages made for gas flow are larger than about

1 m in diameter. The rotor and its airfoils are

carved out of a single wafer, as shown in the

figure. Additional plumbing and bearings are

etched onto the wafers that are to sandwich the

rotor. Combustion occurs just outside the

rotor, at the same wafer level, spinning it by

pushing on its airfoils from the outside. At more

than a million rpm, these turbines make no audible noise. Electricity will then be generated

using, for example, a tiny generator. The fuel source could be packaged with the engine or come

as a replaceable cartridge like a cigarette lighter. In terms of power density, the little engine will

easily beat batteries, with an output of somewhere between 50 and 100 watts! (Pritchard &

Leylegian, 2011)


5/10

4. Commercial applications

Transport Means

Pio Szyjanowicz from Cosworth have developed a

supersonic vehiclethat can travel at a top speed of

1000 miles per hour. The secret of such an amazing

performance lies, not only in the engine of the car, but

mostly on its aerodynamics(on right).

The same design principles are now being used the

manufacture the newest boat, and submarines to

improve the aquadynamicsof the machines. New

airplane wing designs have also being engineered to

optimise the flight. M shape has been found to provide

stability for gliding and W configuration for high maneuverability. These made it possible for

scientists to reach difficult airspaces such a forests. (Cox, 2012)

Mp3 players

Another interesting application of FMs is probably the

inside of the famous MP3 player. The data reading

components consist of reading head mounted very

closely to a rapidly turning tiny disc ( 500 rpm). Thedisc has to be held in place so that it does not touch the

reading head. For this purpose, former players were

equipped with Ball bearings(BBs) to hold the disc.

The problem is that BBs have a lot of components and

are noisy. Fortunately, the latest music players are

supplied with Fluid Dynamics Bearings(FDBs)

which are durable, much less noisy and allow rotation

speeds exceeding 15000 rpm which make data reading

even faster! (Pritchard & Leylegian, 2011)

The picture on the right show a FBD from a Seagate drive. (Yarvin, 2011)

The FBDs are also used in gyroscopes.


6/10

Fluid Lenses

Fluid Lenses or, liquid lenses, have humanlike properties and are used in cameras and

cellphones. The lenses is generally made up of 2 immiscible liquids. In the example below water

and oil are used. The shape of the oil drop is altered by electrowetting. Both liquids aretransparent, with different indices of refraction but exactly the same density. The cell contains

only those two liquids and this density matching makes the whole lens very stable against

mechanical shocks. The liquid lens external shape is fixed, there is no moving part: only the

internal liquids change shape. The Arctic lens is used for high performance Auto-Focus. (Berge,

2010)

Advantages:

Quick response

High reversibility

Smart fluids

Smart fluids have been developed for many commercial sectors:

i. In automobile suspension systemsto optimise motion under all terrain conditions.

ii. Newest military uniforms contain a thin layer of smart fluid that can be stiffened to

provide strength and protection.


7/10

Falkirk wheel

Boats entering the Wheel's upper gondola are

lowered, along with the water that they float in, to

the basin below. At the same time, an equal weightrises up, lifted in the other gondola.

This works on the Archimedes principle of

displacement. That is, the mass of the boat sailing

into the gondola will displace an exactly

proportional volume of water so that the final

combination of 'boat plus water' balances the

original total mass.

Given the precise balancing of the gondolas and

this simple but clever system of cogs, a very small

amount of energy is actually then required to turn

the Wheel. In fact, it is a group of ten hydraulic

motors located within the central spine that provide

the small amount, just 1.5kWh, of electricity to

turn it! (Bellows, 2006)

5.

Agricultural applications

Study of the atmosphere and oceans

Engineers and scientists have done a lot of research to study the behavior of atmospheric fluids

in order to predict the weather or natural catastrophes. Lately, cases such as microclimates,

tornado formations and tsunamis are carefully examined due. On February 26,Professor Mark Z.

Jacobsonhave shown, using computer simulations, that offshore wind farms with thousands of

wind turbines could have sapped the power of three real-life hurricanes, significantly decreasing

their winds and accompanying storm surge, and possibly preventing billions of dollars in

damages. (Carey, 2014)

The interesting fact is that engineers could have turned a threat into a source (renewable) of

energy! And that is the purpose of a device called Vivace converter, which uses the well-known

phenomenon of vortex-induced vibrations to extract power from a flowing current. (Pritchard &

Leylegian, 2011)


8/10

6. Industrial applications

Computational Fluid Dynamics (CFD)

Computational Fluid Dynamics is a computer aided alternative for engineers to solve fluid flow

equations. Some of the most popular are FLUENT, from ANSYS Inc. and OpenFoam. They are

also used to simulate reactions, flows and dynamics. (Pritchard & Leylegian, 2011)

The picture on the right shows the

pathlines around a Formula 1 (from

FLUENT-image courtesy of ANSYS,

Inc. 2008.)

Lubricants

Lubricants are used in machinery to reduce friction, wear and energy consumption. A good

lubricant should be

a) Keep surfaces separateunder all loads, temperatures and speeds, thus minimising

friction and wear.

b) Act as a cooling fluidremoving the heat produced by friction or from external sources.

c) Remain adequately stablein order to guarantee constant behaviour over the forecasted

useful life.

d) Protect surfacesfrom the attack of aggressive products formed during operation.

e) Fulfil detersive and dispersivefunctions in order to remove residue and debris that may

form during operation.

Lubricants should therefore be chosen wisely. (SrivaStava, 2014)

Exploitation of wind energy

Since the last decade, engineers are aware of the global warming

problem and are now moving to renewable sources of energy.

Subsequently, wind energy has been more and more used, wind

turbines have been redesigned to optimise the process.

FloDesign Wind Turbine(on right), a spin-off from theaerospace company FloDesign based in Wilbraham,

Massachusetts, is developing a prototype that, according to CEO

Stanley Kowalski III, will be up to three times more efficient than

conventional wind turbines. Theoretically conventional wind

turbines capture a maximum of 59.3 percent of the wind energy.

The new design generates as much power as a conventional wind turbine with blades twice as

big. The smaller blade size of the new design means the FloDesign Wind Turbine could be


9/10

packed closer together than conventional turbines, increasing the amount of power that can be

generated per acre of land. Because its blades are lighter and smaller, the design starts spinning

and generating power at lower wind speeds, and it is more tolerant of unstable wind patterns,

making it excellent for windy regions where large turbines cannot be used, such as in cities.

(Pritchard & Leylegian, 2011)

7. Bibliography1) Anon., 2011.Requirements and the properties for lubricants. [Online]

Available at: http://www.eni.com/en_IT/products-services/automotive-lubricants/about-

lubricants/requirements-properties-lubricants/requirements-properties-lubricants.shtml

[Accessed 24 September 2014].


10/10

2) Bellows, A., 2006. The Falkirk wheel. [Online]

Available at: http://www.damninteresting.com/the-falkirk-wheel/


3) Berge, B., 2010.Liquid lense for auto focus. [Online]

Available at:http://www.varioptic.com/media/uploads/publication/varioptic_liquid_lens_technology_2

010_12_02.pdf


4) Carey, B., 2014. Offshore wind farms could tame hurricanes before they reach land,

Stanford-led study says. [Online]

Available at: http://cee.stanford.edu/news-events/news/offshore-wind-farms-could-tame-

hurricanes-they-reach-land-stanford-led-study-says


5) Cox, C., 2012. Supersonic Car Designed to Become World's Fastest. [Online]

Available at: http://abcnewsradioonline.com/world-news/supersonic-car-designed-to-

become-worlds-fastest.html


6) Genuth, I., 2007.Engine on a Chip. [Online]

Available at: http://thefutureofthings.com/3063-engine-on-a-chip/


7) Nicholson, C., 2013.How does a Dyson Air Multiplier work?. [Online]

Available at: http://tradecc.net/abs-bladeless-fan.html


8) Pritchard, P. J. & Leylegian, J. C., 2011.Fox and McDonald's Introduction to Fluid

Mechanics. 8th ed. s.l.:John Wiley & Sons, Inc..

9) SrivaStava, S. P., 2014.Developments in lubricant technology.New Jersey: John Wiley

& Sons, Inc..

10)Yarvin, N., 2011. Usenet Archives. [Online]

Available at: http://yarchive.net/blog/computers/computer_fan_bearings.html


various applications of fluid mechanics

Documents