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In this paper the modeling of combined heat and power (CHP) system driven by Stirling engine has been discussed. The system consists of one beta type Stirling engine as the prime mover, heat recovery system, power generator and the auxiliary boiler. The analysis of the Stirling engine is a non-ideal adiabatic analysis. To increase the accuracy of modeling, the frictional and thermal losses of Stirling engine are considered in comparison of other previous studies and the non-ideal adiabatic analysis is performed using a developed numerical code in MATLAB software. For model validation, the operational and geometrical specification of the GPU-3 Stirling engine was used and the results were compared with experimental results and other previous models. Then, one beta-type Stirling engine was proposed as prime mover in cogeneration system for building applications. The use of the cogeneration systems in building applications becomes more common, which system from the perspective of the fuel consumption and pollution emission, have a significant advantage in comparison with the other conventional systems. For this purpose, the effects of engine frequency, regenerator length, and heat source temperature on fuel consumption and pollution emission of system were examined and proper engine design parameters were selected. Finally, the electric power and thermal power were achieved 11263 W and 21653 W, respectively, with reduction in fuel consumption and pollution emission of 37% and 42%, respectively.

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In this paper, optimization phase angle of alpha Stirling engine performed step by step method. After studying on the operation of various types of Stirling engines, the effect of the phase angle on the power and efficiency of Alpha Stirling engines was studied. The kinematic modeling of volumetric compression and expansion volumes has been done by ADAMS software. Then, the linearization of the thermodynamic equations was carried out on the basis of analysis of the isothermal and five-volume adiabatic stirling cycles to obtain the initial solution of its effective parameters on the power and efficiency. To optimize the phase angle between compression and expansion pistons, stepwise numerical solution of the stirling cycle was performed. Comparison of numerical solution with experimental data indicates an error rate of less than 5.3%. The simulation results show the optimum phase angle of 103 °. At this optimal angle, the results indicate an increase of 4.8% of the output power rather than the output power at a 90 ° pre-aligned angle. Simulation results indicate an improvement of 1.2% of the Alpha Stirling engine efficiency by adjusting this phase priority angle to the efficiency at 90 °.