How Is Heat Transferred During Gas Expansion in a Diesel Engine?

[junec21]

Question ...

i have problem with these 2 questions.i been cracking my head the whole day about this/ anyone please help. please write down the steps for me if possible. thanks a lot in advance.

1) 0.25 kg of combustion gas in a diesel engine cylinder is at temperature of 727°C. The gas expands at constant pressure until its volume is 1.8 times its original value. For the combustion gas, R = 0.302 kJ/kgK and Cp = 1.09 kJ/kgK. Find the following:
a) temperature of the gas after expansion
b) heat transferred
c) work transferred

2) A quantity of gas has an initial pressure and volume of 0.1 MN/m2 and 0.1 m3, respectively. It is compressed to a final pressure of 1.4 MN/m2 according to the law pV1'26 = constant. Determine the final volume of the gas.

 

[Hootenanny]

i have problem with these 2 questions.i been cracking my head the whole day about this/ anyone please help. please write down the steps for me if possible. thanks a lot in advance.

Hi Junec & welcome to PF,

What have you attempted thus far?

 

[rock.freak667]

i have problem with these 2 questions.i been cracking my head the whole day about this/ anyone please help. please write down the steps for me if possible. thanks a lot in advance.

1) 0.25 kg of combustion gas in a diesel engine cylinder is at temperature of 727°C. The gas expands at constant pressure until its volume is 1.8 times its original value. For the combustion gas, R = 0.302 kJ/kgK and Cp = 1.09 kJ/kgK. Find the following:
a) temperature of the gas after expansion
b) heat transferred
c) work transferred

a)If you know it expands at constant pressure...What does that mean for Volume and Temperature? (Check what Charles's law says about it)
b)What is the definition of C_p?
c) Do you know a formula for finding the Work done by a gas when it expands its volume at a constant pressure?