저 NOx용 2단 열교환기가 장착된 가정용 보일러 연소실의 열전달 및 유동 수치해석

Abstract

In this work, a numerical investigation is performed for the combustion chamber of domestic gas boiler with 1-stage and 2-stage heat exchanger. The fluid flow and heat transfer performance is provided with a structure change of heat exchanger. The numerical solution shows that, compared to the 1-stage heat exchanger, the increase in the heat transfer in the 2-stage heat exchanger is higher than that of the pressure loss, which proves the excellent performance of this 2-stage heat exchanger. The temperature of combustion chamber with 2-stage heat exchanger is lower than that of 1-stage. This effect reduces thermal NOx with decrease of high temperature staying time of the combustion gas.