import math
# Variable declaration
T_e=3;# The evaporating temperature in °C
T_in=20;# The temperature of air entering coil in °C
T_out=11;# The temperature of air off coil at full air flow in °C
T_c=35;# The condensing temperature in °C
af=(1-0.15);# The reduced air flow
# Calculation
LMTD=((T_in-T_e)-(T_out-T_e))/math.log((T_in-T_e)/(T_out-T_e));# K
T_aoff=T_in-(T_in-T_out)/af;# Air off coil at 85% air flow (°C)
Cp=(af)**0.8;# Coil performance at 85% air flow (°C)
LMTD_85=LMTD/Cp;# LMTD at 85% air flow in K
print"\nLMTD at 85 percentage air flow=%2.1f K(error)"%LMTD_85