Análisis de un motor Stirling para operar a baja ΔT

Abstract

[ES] El objetivo de este trabajo es modificar la temperatura de operación de un motor Stirling tipo beta, el cual fue originalmente diseñado y optimizado para trabajar a alta temperatura, mediante la sustitución del cigüeñal. La modificación consiste en cambiar el cigüeñal actual, con una carrera de 38 mm, por otro de 20 mm. Con esto se espera que el motor trabaje a una ΔT óptima de aproximadamente un 50% con respecto a la configuración original. El procedimiento a seguir será llenar el motor con Helio, tomar algunas medidas en la configuración actual, como la potencia entregada en función de la temperatura de operación y la presión del Helio en la cámara. A continuación se cambiará el cigüeñal y se volverán a registrar experimentalmente los parámetros de interés, con el fin de analizar el efecto que tiene el cambio de cigüeñal en las prestaciones del motor.

[EN] In this project, the analysis of a beta-type Stirling engine is carried out. The engine was constructed by other students of this university as part of their bachelor thesis in 2011, and then started and tested in the current configuration as part of another bachelor thesis in 2013. Despite it was originally designed and optimised for use with a high-temperature heat source, it can be modified for low ΔT operation by changing the crankshaft for a new one with a reduced stroke. In the beginning, the plan for the project was to make the engine operational again and test it in its current configuration, in order to compare the results with the results of the previous report. After that it was planned to make the necessary modifications, and test it for low ΔT operation, with the exhaust gases from another engine as the heat source. It was filled with helium and tested with a propane burner as heat source, and these results were compared with the ones obtained in 2013. Then the crankshaft was removed, in order to replace it for the new one. However, when it was tried to mount the guiding rings on it, they did not fit. Since there was not time enough to order new ones, the engine could not be tested in low ΔT operation