Thermal expansion

[FrankHovis]

After some help if possible on calculating how much air expands when heated. Ive been online and viewed the examples but I'm too thick to work it out

My question is this...

I have an exhaust volume (not a car!) of 32,200m³ per hour at 110 celcius. What would the volume be at 0 celcius?

I'm trying to work out the fresh air intake required for a large dryer and all the documentation I have only states exhaust volume at 110 celcius.

Any help gratefully appreciated

[tank slapper]

The combined gas law will give you a value for the volume at 0C:

P1.V1 / T1 = P2.V2 / T2

where P is pressure, V is volume and T is temperature.


Rearranging to find V1 gives:

V1 = P2.V2.T1 / T2.P1

We are assuming a constant pressure, so P1 = P2:

V1 = V2.T1 / T2

So substituting your figures gives (temperatures must be in Kelvin):

V1 = 32200m^3 * 273.15K / 383.15K

V1 = 22955.6 m^3


So the intake volume is about 22,955 m^3 per hour.

[FrankHovis]

The temp conversion confused the hell out of me and I gave up after that. I'd worked out 23,500 based on a much smaller machine we have which I've already got all the figures for, but wasn't sure it was a simple case of using the same percentage of expansion. Turns out I wasn't a million miles away!

Many thanks for your help.