采用焓差法进行冷却塔热力计算时，蒸发水量带走热量的系数取值及其在计算公式中的位置，不同的规范标准之间相互矛盾。通过理论分析、计算比较，指出了该系数较为合适的定义、在计算公式中的位置、计算公式以及对热力计算的影响，认为热力计算中可以不考虑修正系数K的影响。

There is a coefficient of bring-off-heat due to water evaporation whose value and position in calculation formula are different in various standards, when the enthalpy difference method is used for the thermal calculation of cooling tower. The paper presented suitable recommendations for the coefficient on definition, position and calculation formula, based on the theoretical analysis and comparison. The influence of the coefficient on the thermal calculation was studied, whose result showed that the impact of factor K could be ignored in the thermal calculation.