- #1
Angelos K
- 48
- 0
I wish to understand evaporative cooling. Apparently the principle consists in pumping the vapour above a bath, hence extracting it's most energetic corpuscles and achieving cooling.
The aim is to derive the cooling power. My textbook states:
[tex]\frac{dQ}{dt} = L\frac{dn}{dt} \propto p [/tex]
L being the latent heat per mol and p the gas pressure. I don't see why the proportionality holds. Sorry if I miss something simple, I'm battling a light cold ;-)
[From here on one can use the gas pressure formula
[tex] p = p_0 \exp(-\frac{L}{RT})[/tex]
to demonstrate, how with linearly decreasing temperature the cooling rate decreases exponentially]
Thanks in advance for any help!
The aim is to derive the cooling power. My textbook states:
[tex]\frac{dQ}{dt} = L\frac{dn}{dt} \propto p [/tex]
L being the latent heat per mol and p the gas pressure. I don't see why the proportionality holds. Sorry if I miss something simple, I'm battling a light cold ;-)
[From here on one can use the gas pressure formula
[tex] p = p_0 \exp(-\frac{L}{RT})[/tex]
to demonstrate, how with linearly decreasing temperature the cooling rate decreases exponentially]
Thanks in advance for any help!