Unit (cm) any alternative to the obvious?

[frodft]

The problem involves a spray drying process in which a liquid containing dissolved or suspended solids is sprayed into a chamber that has air flowing into it which contains water.

One outlet stream has the wet air, and the other has dry solids.

The Air inlet stream is described as having a temp of 167 celsius and -40cm H₂O

My question is, what do they mean my cm? If they meant centimeters then this problem can't be solved because I need more than a one-dimensional measurement of the amount of water in that stream. There is no information about the dimensions of the pipe, and there is no more information about that stream than I have stated. So the obvious roadblock is if there is another unit for cm or they meant something else.

 

[pongo38]

pressure?

 

[Zryn]

Cubic Metre ?

 

[frodft]

apparently it is a unit of pressure that was used in the '80's in medicine. I don't know what it was doing in my chemical engineering textbook 30 years later but there you go.

 

[pongo38]

In this case isn't "-40cm H2O" just a suction = ro*g*h where ro is the density of water, g is the gravitational constant, and h the 40 centimeters. That's not particularly medical.