# Help with compressible flow problems

1. Jul 23, 2014

### thepipplesh

1. The problem statement, all variables and given/known data

Calculate the pressure increment required to isentropically compress air and water at 1 atm and 20°C to 50% of their volume. The isentropic bulk modulus for water at 20°C is 2.24 109 N/m2, and air can be considered an ideal gas with γ =1.4 .

2. Relevant equations

$\frac{P2}{P1}$=$\frac{V1}{V2}$γ=$\frac{T2}{T1}$$\frac{γ}{γ-1}$

3. The attempt at a solution
$\frac{P2}{1013.25Pa}$=(0.5)1.4=383.9 Pa

I am reading ahead on the lecture notes which literally just show me how to derive the equation i provided so I have no clue at all what i'm doing would appreciate any pointers/ resources to get more practice on these types of questions :)

2. Jul 27, 2014