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[VLCENG]

Hello,

I have a question that requires me to design a moka coffee pot with certain specifications. There is one aspect of it that I don't know how to go about. Lets say I need to make 1L of espresso coffee in a certain amount of time, how would you calculate the necessary initial volume of water in the pressure vessel?

It will obviously have to be more than 1L, as some of the water will have to evaporate in the pressure vessel to add pressure with the steam and hence be able to make coffee. 

So my question is, how would you go about determining the volume of water you would need initially accounting for the amount you would need to evaporate to push the liquid water up the pot.

 

I think the explanation of the question is a bit confusing sorry for that, will give any more details you ask.

Edited by VLCENG, 01 December 2020 - 02:43 PM.

[Pilesar]

To find the mass of water in a specific volume of steam, I would use the steam tables (Keenan and Keyes is the one I use.) It has the data you need for density of liquid water and steam for different pressures and temperatures. You can also use the steam tables to determine how much heat is required for heating and vaporization assuming no heat loss to the vessel.