Heat exchanger, Heat transfer, Fin efficiency, Heat transfer coefficient
This study discussed the estimation of the fin efficiency and the pure-heat transfer coefficient in the heat exchanger. One hundred twenty cases of plate fins having known heat transfer coefficients were tested numerically to investigate the validity of the previous classical theory on the fin efficiency. The conventional theory on the fin efficiency was only useful when the value of NTUf was near zero. However, it was not useful at high NTUf and low fin efficiency in the heat exchanger. A new definition of fin efficiency and a model for pure-heat transfer coefficient are suggested, which are applicable to the heat exchanger. The present model reduced error greatly than the classical model in the estimation of the pure-heat transfer coefficient at 0 < mL < 2, 0 < NTUf < 2.5.