The Research Of A Heat Transfer Model Of High Pressure Generatorwith Fire Tubes And Its Application

With its advantages of simple structure and convenient maintenance, the fire tube generator is widely used in LiBr/H₂O absorption system. However, when it comes to combustion chamber radiation and gas convection, the research on them is insufficient. In this paper, the heat transfer of the fire tube high pressure generator is systematically studied and the computational model of heat transfer is established. The computational models have been validated by experimental data and are used to analyze the high pressure generator's heat transfer in direct-fired LiBr/H₂O absorption chiller heater.In order to calculate the heat transfer in high pressure generator, computational models of exhaust gas, LiBr/H₂O solution and steam gas are built. In this paper, the computational model of heat transfer is developed and the program is also given.Experiments are carried out and the results show that: the relative error of exit gas temperature on hearth between calculation data on experimental data processing model and testing value does not exceed 4.2%, while rating consuming oil; the relative error between calculation data on experimental data processing model of high pressure generator heat transfer and absorbed heat in hot water does not exceed 7.0%; the compensation factor of corrugated tubes corresponding intensification heat transfer is 1.85; the relative error of the gas temperature in the middle and exit of convection segment between calculation data on heat transfer model and testing value does not exceed 6.1%; the veracity of the data processing model and the computational model is adequate.The models are used to analyze the heat transfer of high pressure generator of a direct-fired LiBr/H₂O absorption chiller heater respectively with corrugated tubes with twisted-type inserts, plain tubes, plain tubes with twisted-fired inserts. It comes out that the models can analyze the heat transfer effectively.The heat transfer model of a high pressure generator with fire tubes developed in this paper can forecast the state of heat exchange quantitatively, offere theory gist for experiment research of fire tubegenerator, and can provide important reference for the design of fire tube generator. The research of this paper can offer technical support for on-line control of direct-fired LiBr/F^O absorption heater chiller.