Design of a Novel Multicylinder Stirling Engine

Stirling engines are machines based on a simple working principle and are well known for their theoretical high thermal efficiency. Technical drawbacks related to the high temperatures required for achieving high values of thermal efficiency and output power have limited their spread to low-power applications. Stirling engines can operate with almost any source of heat. For this reason, these engines are currently installed in applications with renewable energy sources for combined heat and power generation (CHP), where the mechanical output power is usually converted into electrical power. The paper is focused on the design and analysis of a novel mechanical configuration with a higher number of cylinders than current commercial solutions. The performances of several multicylinder configurations are evaluated via numerical simulations, taking into account the dynamics of the mechanism and the thermal aspects of the cycle. Finally, a prototype of the main mechanism, which allows the number of cylinders to be increased, is introduced and briefly described.