The Research Of Stirling Circle Heat Recovery Device

This thesis mainly deals with the designing procedures of Stirling-circle heat recovery device. Basic structures of typical Stirling engines, which include an expander, a heater, a regenerator, a cooler and a compressor, were introduced briefly, as well as the role that the above 5 elements play in the isolated circling system who realizes Stirling circle. The courses of Stirling circle, which consist of 2 constant-volume courses and 2 adiabatic courses, were illustrated and summarized in detail respectively. 3 commonly used Stirling-circle analytical methods were also analyzed and compared carefully. Comparison of the 3 analytical methods mainly focused on their scopes of application and veracity so that the comparison could give some clues about the criteria to choose proper analysis method and the way to narrow research objective, simplify the question and improve simulation efficiency.Other than the introduction of basic concepts and analysis methods, a simulation program based on Fixed-temperature analysis and coded with C++ was also carried out. And according to the simulation results of Ford 4-215DA Stirling engine yielded both by the above Fixed-temperature Analysis program and Adiabatic Analysis, a further comparison between the veracities of FA and AA were made. Corresponding amendment equation sets were quoted to explain the formation mechanism of calculative error, predict its tendency and provide initial optimizing idea. An initial design of small Stirling-circle heat recovery engine was carried out basing on the above theoretical analysis. Detailed simulated analysis of given structural and working parameters of the designed engine were also done by the above mentioned FA simulation program.On the other hand, CFD analysis of 3 major heat exchangers (the heater, the regenerator and the cooler) were accomplished by FLUENT 6.0.3 to implement optimization of heat exchangers. The regular patterns of internal heat exchange in nest tube were summarized according to the results of the CFD analysis. And an optimized inner diameter of the heater’s tube was also concluded basing on the very same result. After that, a new optimizing method based both on FA and Finite Time Thermodynamics was introduced. The new optimizing method provides a new methodology of Stirling engine optimization. Procedures of inserting FFT analysis into FA-based simulation and optimization were also illustrated and exemplified briefly. Although the analysis of the new optimizing methodology constructed the basis of its further research, there were still some flaws in the novel analytical method, which were also mentioned and explained elaborately in the last part of this thesis.