A cylinder contains the helium gas with a volume of 0.1 m3 at a pressure of 220 kPa.

Question

The gas is compressed to a volume of 0.02 m3. The process is adiabatic and the
specific heat ratio of the gas is 1.66. Determine
(a) the pressure in the cylinder after compression;
(b) work done to reduce the volume of the gas; and
(c) percentage change of the temperature.

Answer 1

(a) Use the relation P V^1.66 = constant

(b) Work = Integral of P*dV. Express P as a function of V to do the integration

(c) Use the relation PV/T = constant to get the new T.

OR use the isentropic compression relation
(T2/T1) = (V1/V2)^(g-1)
where g = 1.66

You should get the same answer either way.