Question

1)

The air temperature is 15ºC. Determine the saturation vapor pressure at this temperature. If the dew point temperature is found to be 10ºC, determine the vapor pressure in the air, and calculate the relative humidity for both temperatures.

Answer 1

The saturation vapor pressure Ps can be determined by using the following formula

Here, t is the temperature in ^oC and Ps in pascals. Substituting t in above we get

Saturation pressure is 1698 Pa.

The vapor pressure P in the air can be calculated as

Here, t_d is the dew point temperature in ⁰C.

10 P = 610.78 exp[(T,2383 ) × 17.2694

The relative humidity R can be given as

$R=rac{P}{P_s}$

So the relative humidity will be 0.72 x 100=72 %