Testing method of hot end air leakage rate of air pre-heater

The invention discloses a testing method of the hot end air leakage rate of an air pre-heater. The method includes the following steps that firstly the hot air temperature Ta,2, the cold air temperature Ta,1and the smoke temperature Tg,0 are obtained, wherein the hot air temperature refers to the temperature of the hot air flowing out of the air pre-heater, the cold air temperature refers to the temperature measured when the cold air enters the air pre-heater, and the smoke temperature refers to the temperature measured before the smoke enters the air pre-heater and is mixed with hot end leaked air; secondly, the smoke side efficiency eta of the air-pre-heater and the mass flow rate ratio km between the smoke and the air are obtained; thirdly, the hot end air leakage rate AL of the air pre-heater is obtained by taking parameter data obtained in the first step and the second step into a computational formula (1). The method can measure the mass ratio of hot end leaked air and the amount of the inlet smoke, namely the hot end air leakage rate, enables working situations of the air pre-heater to be analyzed and improved conveniently and is an important basis for improving the economy of a boiler system.