Work and heat transfer in internal combustion engine

In summary, the problem involves a two-cylinder internal combustion engine with a starting pressure of 101.325 kPa and a compression ratio of 1/5. The law of compression is given by PV^1.2 = const and the bore and stroke of each cylinder is 0.15 m and 0.25 m, respectively. The task is to determine the power absorbed in kW by compression strokes when the engine speed is set at 500 compression strokes per minute. After solving the given equations, the correct solution is found to be 17.95 kW.
  • #1
Suman_babai
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Homework Statement

: [/B]At the beginning of the compression stroke of a two-cylinder internal combustion engine the air is at a pressure of 101.325 kPa. Compression redeuces the volume to 1/5 of its original volume, and the law of compression is given by PV^1.2 = const. If the bore and stroke of each cylinder is 0.15 m and 0.25 m , respectively, determine the power absorbed in kW by compression strokes when the engine speed is such that each cylinder undergoes 500 compression strokes per minute.

The answer is given as : 17.95 kW

2. Homework Equations : I hv written all formulas in the solution (attachment).

The Attempt at a Solution

:[/B] I hv attached the solution I hv done. Please rectify my mistake... where I am doing wrong..my ans is not matching with the given one.
 

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  • #2
Suman_babai said:
given by PV^1.2 = const.
Are yo usure this is not pV^1.4 ?
 
  • #3
Replusz said:
Are yo usure this is not pV^1.4 ?
that could be a printing mstake... thanks... this book is just full of calculation errors.
 
  • #4
And if you calculate it with 1.4? do you get the right answer? (it is 1.4 because for adiabatic expressions pV^(1+2/f)=const. and f=5 for air. )
 
  • #5
Replusz said:
And if you calculate it with 1.4? do you get the right answer? (it is 1.4 because for adiabatic expressions pV^(1+2/f)=const. and f=5 for air. )
no.. it is coming around 16.(something)... may be the question is wrong.. thanks anyway.
 
  • #6
Suman_babai said:

Homework Statement

: [/B]At the beginning of the compression stroke of a two-cylinder internal combustion engine the air is at a pressure of 101.325 kPa. Compression redeuces the volume to 1/5 of its original volume, and the law of compression is given by PV^1.2 = const. If the bore and stroke of each cylinder is 0.15 m and 0.25 m , respectively, determine the power absorbed in kW by compression strokes when the engine speed is such that each cylinder undergoes 500 compression strokes per minute.

The answer is given as : 17.95 kW

2. Homework Equations : I hv written all formulas in the solution (attachment).

The Attempt at a Solution

:[/B] I hv attached the solution I hv done. Please rectify my mistake... where I am doing wrong..my ans is not matching with the given one.
Here is correct solution bro. V1-V2= Volume swept by piston.
Volume swept by piston not equal to v1, where you went wrong.
 

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FAQ: Work and heat transfer in internal combustion engine

1. What is the main purpose of work and heat transfer in an internal combustion engine?

The main purpose of work and heat transfer in an internal combustion engine is to convert the chemical energy of fuel into mechanical energy, which is then used to power the vehicle.

2. How does work and heat transfer occur in an internal combustion engine?

Work and heat transfer occur in an internal combustion engine through a series of controlled explosions in the engine's cylinders. The hot gases produced by these explosions expand and push the pistons, which in turn power the engine's crankshaft.

3. What factors affect the efficiency of work and heat transfer in an internal combustion engine?

The efficiency of work and heat transfer in an internal combustion engine is affected by several factors, including the design of the engine, the quality of fuel used, the temperature and pressure inside the engine, and the overall condition and maintenance of the engine.

4. How does work and heat transfer impact the performance of an internal combustion engine?

The amount of work and heat transfer in an internal combustion engine directly impacts its performance. The more efficiently the energy from the fuel is converted into work, the better the engine's performance will be. On the other hand, inefficient work and heat transfer can lead to decreased power and fuel economy.

5. Can work and heat transfer be controlled or optimized in an internal combustion engine?

Yes, work and heat transfer in an internal combustion engine can be controlled and optimized through various techniques such as adjusting the air-to-fuel ratio, improving the engine's design and components, and implementing technologies like turbochargers and direct injection. Regular maintenance and tuning can also help improve work and heat transfer efficiency in an internal combustion engine.

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