3 replies to this topic

[Dudesons123]

Dear Engineers/Scientists,

 

I have a problem question regarding mass transfer and I was wondering if you could help me with it? I have already written down my working. Any help would be great. Thanks in advance.

 

A water layer of depth h at temperature T and pressure P at the bottom of a conical flask (i.e. a flask with circular cross-section) evaporates into stagnant air and exits the top of the flask into a fast moving stream of dry air. Starting with the General Diffusion Equation, show that the time required for complete evaporation of the water is given by

 

Then I had to equate the flux*Cross-sectional Area with the rate of change in the number of moles in the flask.

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Edited by Dudesons123, 26 April 2017 - 10:53 PM.

[breizh]

Hi ,

Consider the material attached to support your work.

Hope this helps

Breizh

[Dudesons123]

Am I on the right track of getting the right answer?

I just don't know how to find the next step.

Edited by Dudesons123, 28 April 2017 - 10:27 PM.

[Dudesons123]

I have read the file that you sent me but I am still stuck because in this problem I am faced with a truncated cone instead of a cylinder. I keep ending up with the wrong answer. Please help me.

Edited by Dudesons123, 30 April 2017 - 08:12 AM.