CHAMELI DEVI GROUP OF INSTITUTIONS

Department of mechanical engineering

Seminar on-

CRYOCAR

AMAN KAPOOR

By-

Topic of interest-

1) Introduction

2) What is liquid nitrogen vehicle?

3) Why nitrogen as a vehicle fuel?

4) Parts of a LNPC

5) Principle of operation

6) Liquid nitrogen propulsion cycle

7) Advantages over electric cars

8) Efficiency

9) Drawbacks

10)Why not commercialized?

11)Conclusion

INDRODUCTION

Use of alternate resources

PollutionHuman greed

CRYOCAR

uses

Cryogenic fuel

like

Liquid Nitrogen

What is liquid nitrogen vehicle?

It is a vehicle which uses Cryogenic fluid(liquid

nitrogen) as a working fluid.

Propulsion system is a cryogenic heat engine in which

a cryogenic substance is used as a heat sink.

CRYOGENICS

Cryogenic can be defined as the branch of the physics

that deals with the study of the production of very

low temperature (below −150 °C, −238 °F or 123 K) and the

behavior of materials at those temperatures.

Why nitrogen as a vehicle fuel?

High cost and limited availability of fossil fuels like petrol and diesel.

Due to high level of pollution associated with the combustion of fossil fuels the

need of ZEV(Zero Emission Vehicle) has been generated. (presently the

battery powered electric vehicle is the only commercially available ZEV but

not successful due to high initial cost, slow recharge and limited range).

And the most important is the huge availability of Nitrogen gas(78% of air is

nitrogen).

Note: According to Petroleum Conservation and Research Association

petroleum production will be at its peak in 2012 and is likely to

decrease after that.

Parts of a LNPC

1)

Cryogen

storage

vessel

A pressurized tank(24 gallon) to store liquid nitrogen.

Low boil-off rate , minimum size and mass and reasonable cost.

2)

Pump

The pump is used to pump the liquid nitrogen into the engine.

Operating pressure between 500-600psi

3)Economizer

A preheater , called an economizer , uses left over heat in

the engine’s exhaust to preheat the liquid nitrogen before

it enters the heat exchanger.

Improves efficiency.

Parts of LNPC…….

4)Heat

exchanger

A primary heat exchanger that heats (using

atmospheric heat) LN2 to form N2 gas, then heats gas

under pressure to near atmospheric temperature

Parts of LNPC.........

5)

Expander

An Expander to provide work to the drive shaft of the

vehicle.

Principle of operation LN2 at –320oF (-196oC) is pressurized and then vaporized in a heat exchanger by

ambient temperature of the surrounding air.

This heat exchanger is like the radiator of a car but instead of using air to cool

water, it uses air to heat and boil liquid nitrogen.

Liquid N2 passing through the primary heat exchanger quickly reaches its boiling

point.

The N2 expands to a gas with a pressure of 150 KPa.

The pressurized N2 gas drives the motor.

The only exhaust is nitrogen, which is major constituent of our atmosphere.

Energy+N2(l)-->N2(g)

Hence, there is no pollution produced by running this car.

Liquid nitrogen propulsion cycle

Cryogen storage vessel

Pump

EconomizerHeat

Exchanger

Expander Engine

Advantages over electric cars

A liquid nitrogen car is much lighter and refilling its tank takes only about 10-

15 minutes.

The exhaust produced by the car is environmental friendly.

A cryogenic car could have three times the range of an electric car of the

same weight and no battery disposal concerns

ZEV

Efficiency-

The LN2 car can travel 79 miles(127.58 km) on a full 24 gallon(90 liter)

tank of liquid nitrogen going 20 MPH.

Its maximum speed is over 35 MPH.

Drawbacks:

The N2 passing through the tubes of the heat exchanger is so cold that

the moisture in the surrounding air would condense on the outside of the

tubes, obstructing the air flow.

Then there's the safety issue. Should a nitrogen car be kept in a poorly

ventilated space and, if the Nitrogen leaks off, it could prove fatal.

Why not commercialized?

Even though the technology is 10 to 12 years old, still it has not come to the

market for two reasons.

Safety issues have not been sorted out as yet.

Lack of funds for research.

SAD

Conclusion

In a real sense, the more such vehicles are used, the cleaner the air will

become

Time to recharge , infrastructure investment , and environmental impact

are among the issues to consider , in addition to range and performance

, when comparing the relative merits of different ZEV technologies.

Extra research work is needed to utilize the most of the available energy