Adiabatic Compression (Example)

[@kina4288]

So clear and insightful. Cannot thank you enough.

[@gokuraja7724]

Sir, what if I have a change in pressure and temperature and v=constant what is the formula for change in pressure of initial p to final p in adiabatic expansion ,how to calculate pressure sir?

[@PhysicalChemistry]

These equations assume ideal gases, so if you want to calculate the pressure change of an adiabatic expansion, you can just substitute V = nRT/P in these equations. However, be careful. You can't have V=constant, because this is an adiabatic **expansion**. The volume must change.

[@mortezakhoshbin]

Thanks alot prof.stuart If we have a real gas how much temperature will deviate from these equation. I was using simulation software that there was a compressor and the reported temperatures was match with these formulas! So i was wonder if these are for ideal gas, why an industrial software uses these for calculation. Or im wrong and there is a little deviation

[@PhysicalChemistry]

There will definitely be some deviation. Both because real gases are not ideal, and because a real-world process won't be perfectly adiabatic. But if the gas is not too dense, and if the software is using an accurate (perhaps non-ideal) heat capacity, then the prediction will be pretty close. I can't say whether your simulator is using ideal or real gas models, or emotional data.

[@mortezakhoshbin]

@@PhysicalChemistry Being a teacher is a blessing and you deserve it. Thanks alot❤️

[@qbeetrader5396]

Sir, can i use same formula for compress air in pressure chamber?

[@PhysicalChemistry]

It depends on the conditions. This formula is valid for any (1) adiabatic compression or expansion of (2) an ideal gas, If the compression is not adiabatic, or if the gas doesn't behave ideally, then this equation is only approximate, or may not be accurate.

[@qbeetrader5396]

​@@PhysicalChemistry i just want to increase ambient air temperatur from 30 deg Celcius to 90 deg Celcius in pipe pressure chamber as quick as possible. My step is: turn on the heater element in pipe than filled ambient air with air compressor. I'm sorry my English

[@kukulele8182]

298 x two to the two tirds = 470. Why is this so complicated ? What is gamma ?

[@kukulele8182]

i needed three days to figure this out, its exponents, never before have i bumped into them

[@sharongeorge8239]

Best❤️

[@PhysicalChemistry]

Thanks