Investigation on the flow field in the connection sectionbetween two heat exchangers of a condensate gas water heater

This paper investigates a new type of condensate gas water heater,which consisted of a burner,a high temperature heater exchanger (i.e.rut exchanger) and a low temperature heater exchanger (i.e.subjoin exchanger or condensate exchanger).These components are set vertically one by one with a same rare plane.The subjoin exchanger is set at top and smaller in width than the rut exchanger and burner.A lean plane with some holes is set in the connect channel between the two exchangers aslant.As the flue gas flow crows the subjoin heater exchanger,the gas temperature will be below the dew point,and the same steam in the gas condensed into water.These blobs drip to the lean plane and are collected through the holes on the plane.The flow field of the connect channel and subjoin exchanger affected by the dip angle and holes distribution of the lean plane is investigated with CFD.The results show that there is a suitable configuration about the dip anger,hole's diameter and distribution of the lean plane.With that configuration,the flue gas can wash the tubes of the subjoin heat exchanger homogeneously in a higher velocity than the rut exchanger does.