=B5 * (B4/100) Cell B7:
=0.62198 * B6 / (B2 - B6) Cell B8:
For (pressure in kPa, temperature in K):
[ W = 0.62198 \cdot \fracp_wP - p_w ] where ( P ) is total atmospheric pressure (typically 101.325 kPa at sea level). The factor 0.62198 is the ratio of molecular weights of water (18.01528) to dry air (28.9645).
– solved iteratively from ( p_ws(T_dp) = p_w ).
[ p_ws = 0.61094 \cdot \exp\left( \frac17.625 \cdot T_dbT_db + 243.04 \right) ] where ( T_db ) is in °C, result in kPa. 1. Humidity ratio from vapor pressure
=B5 * (B4/100) Cell B7:
=0.62198 * B6 / (B2 - B6) Cell B8:
For (pressure in kPa, temperature in K): psychrometric chart calculator excel
[ W = 0.62198 \cdot \fracp_wP - p_w ] where ( P ) is total atmospheric pressure (typically 101.325 kPa at sea level). The factor 0.62198 is the ratio of molecular weights of water (18.01528) to dry air (28.9645). =B5 * (B4/100) Cell B7: =0
– solved iteratively from ( p_ws(T_dp) = p_w ). psychrometric chart calculator excel
[ p_ws = 0.61094 \cdot \exp\left( \frac17.625 \cdot T_dbT_db + 243.04 \right) ] where ( T_db ) is in °C, result in kPa. 1. Humidity ratio from vapor pressure