Thermomechanical analysis of four-lobe rotors in a roots-type multi-recompression heater

The Multi-Recompression Heater (MRH) is a mechanical device which compressively heats a gas stream to very high temperatures. Potential applications are extensive. The present study analyzes the thermal, stress, and displacement fields experienced by four-lobe impellers operating under a variety of typical conditions. The ABAQUS finite element code was used for the computations. Various transient convective boundary conditions were simulated in the thermal-stress/ displacement analyses. A variety of pressure distributions and rotational speeds were considered in determining the mechanical stresses and displacements.