As shown in the sketch below, moist air enters an insulated tube at station 1with properties T₁, P₁, and ω₁. Moisture is added to the air stream as it passes through a wick and exits at station 2 saturated with moisture (i.e., ϕ₂ = 100%) at a temperature T₂. The pressure at station 2 can be assumed to be the same as at station 1. The make-up water is supplied to the wick as saturated liquid, also at T₂. This process is referred to as an adiabatic saturation process and the device that accomplishes this is an adiabatic saturator.

A. Derive an expression that allows you to calculate ω₁ from a knowledge of T₁, P₁, T₂, P₂ (= P₁), and P_sat (T₂).

B. Apply your result from part A to obtain a numerical result for the specific humidity ω1 and relative humidity ϕ₁ for the following conditions: T₁ = 299.8 K (80 F), T₂ = 293.1 K (68 F), and P = 1 atm.

Transcribed Image Text:

T₁ 001 P₁ Wick Saturated liquid at T2 T₂ 92=100% P₂ (= P₁)