Electro-dynamic Analysis of the Harwell Thermo-Mechanical Generator: Comparison of Theoretical and Experimental Results

An electrodynamic analysis developed by the authors for the performance prediction and the design of free-piston Stirling engine/linear alternator systems is applied in this paper to an existing and operating plant in order to reach the following objectives: firstly, to obtain a validation of the theoretical model by means of a comparison with experimental results; secondly, to quantify separately the effect of the various elements which have a stabilizing influence on the system when the load is changing. In order to illustrate the above features, we have considered, as an example of a thermoelectric dynamic energy conversion system, the well known HARWELL Thermo-mechanical Generator (TMG), whose testing has been carried out, and the results provided, by Cooke-Yarborough for authors' purpose. For this engine a suitable thermodynamic analysis has been introduced because the adiabatic model cannot be used and the isothermal one leads to not completely satisfactory results.