Wet bulb temperature calculation - AWS810

Wet bulb temperature is calculated iteratively as follows:

1. First the initial estimate of wet bulb temperature is calculated with the following formula:

   $T_{wet}=243.12\cdot \frac{\log \left(\frac{P_{ws}\left(T_d\right)}{6.112}\right)}{17.62-\log \left(\frac{P_{ws}\left(T_d\right)}{6.112}\right)}$

2. Then the wet bulb temperature is iteratively re-calculated as long as ABS(P_hit − P_ws(T_d)) > 0.01 with the following formula:

   $T_{wet}=T_{wet}-\frac{P_{hit}-P_{ws}\left(T_d\right)}{2\cdot P_{der}}$

   P_hit and P_der are calculated depending on the value of T_wet:

   • If T_wet > 0:

     $P_{hit}=P_{ws}\left(T_{wet}\right){-0.000662\cdot P}_A\cdot (T_A-T_{wet})$

     $P_{der}=\left(P_{ws}(T_{wet}+0.1)-0.000662\cdot T_A\cdot (T_A-(T_{wet}+0.1))-P_{hit}\right)\cdot 10.0$

   • If T_wet ≤ 0:

     $P_{hit}=P_{wi}\left(P_{wet}\right)-0.000583\cdot P_A\cdot (T_A-T_{wet})$

     $P_{der}=\left(P_{wi}(T_{wet}+0.1)-0.000583\cdot T_A\cdot (T_A-(T_{wet}+0.1))-P_{hit}\right)\cdot 10.0$

P_ws(t) calculation

v Calculation

P_wi(t) calculation