Analysis and comparison of thermodynamic behavior for Stirling and Ericsson cycles ; Análise e comparação do comportamento termodinâmico de ciclos Stirling e Ericsson

Dissertação de Mestrado Integrado em Engenharia Mecânica apresentada à Faculdade de Ciências e Tecnologia ; Stirling and Ericsson engines are external heat engines that offer the ability to use many different heat sources to provide reliable and sustainable power. In this thesis, we compare the Stirling and Ericsson cycles in order to determine in which situations one engine produces more net work output than the other. The net work output equations are derived and are analyzed for three different scenarios: (i) equal mass and temperature limits, (ii) equal mass and pressure or volume, and (iii) equal temperature and pressure or volume limits. The comparison is performed by calculating when both cycles produce the same net work output and then analyzing which one produces more net work output based on how the parameters are varied. In general, the results demonstrate that Stirling engines produce more net work output at higher pressures and lower volumes, and Ericsson engines produce more net work output at lower pressures and higher volumes. For certain scenarios threshold values are calculated to illustrate precisely when one cycle produces more net work output than the other. This thesis can be used to inform the design of the engines and particularly to determine when either a Stirling or Ericsson should be selected for a particular application.Stirling and Ericsson engines are external heat engines that offer the ability to use many different heat sources to provide reliable and sustainable power. In this thesis, we compare the Stirling and Ericsson cycles in order to determine in which situations one engine produces more net work output than the other. The net work output equations are derived and are analyzed for three different scenarios: (i) equal mass and temperature limits, (ii) equal mass and pressure or volume, and (iii) equal temperature and pressure or volume limits. The comparison is performed by calculating when both cycles produce the same net work output and then analyzing which one produces ...