Dear all,

I'm new to the group and would like to benefit from your combined
knowledge on humidity... In fact my question does not relate to
weather, but does relates to calculations of conditions in the
atmosphere of a test rig. It is a very long time since I was doing
these calculations and I am very rusty.

A new test method has been developed for ageing some samples, the test
conditions are as follows;

Pressure 2.1MPa, temperature 85 deg C, liquid water in the bottom of
the pressure vessel.

The people who delveloped the test believe that the samples inside the
pressure vessel will be saturated with water and exposed to the effects
of water and oxygen thereby simulating an accelerated ageing process -
I am unconvinced. They hypothesise that the atmosphere in the test rig
exposes the samples (above the liquid level) to liquid and water
vapour. According to the calculations I have done there is actually
very little water in the atmosphere of the rig...

can anyone assist me?

Under the above conditions as far as I can determine the vapour
pressure of water in the rig is 57.8kPa. Using the Ideal gas law
(pV=nRT) I calculate that there is approx 25ml water in the rig
atmosphere. At this stage I reach the boundary of my capabilities!!

What is the humidity in the chamber? is the air saturated with water
vapour - is it close to the dew point (i.e. will water deposit upon the
samples?)

Apologies in advance for my ignorance in this area and grateful in
advance for your assistance.

Mike