Proof of the Equivalence between Two Calculation Methods of the Sensible Heat Losses

The sensible Heat losses are the most important losses of boiler efficiency, but the calculation condition of ASME PTC4-1998 is different with that of other traditional performances codes such as ASME PTC4.1-1964, GB10184-1988, and so on, leads to two different series of boiler efficiency calculation methods. Because there are so many other different special conditions adopted by different codes, the equivalent of these two methods can not be proofed by validation of specific test data set. To solve this confusion, the enthalpy variation law before and after combustion is obtained by the analysis of process of determination of Heat Value of Fuel, basing on the theory of path independence of Thermal process. Then the equivalent calculation between the two methods is proved theoretically. It would be helpful to further understand the new test code of ASEM PTC 4-1998.