Allison Engine Company has 26 years of experience in vehicular gas turbines with rotating disc regenerators for waste heat recovery including 7 different engine models ranging up to 350 hp. We have completed the first 140 hr of endurance testing on a one-piece extruded ceramic disc regenerator of 231 mm (9.1 in.) diameter. Our disc supplier is finalizing extrusion additives and firing schedule for a lithium aluminum silicate material with up to 85% mined mineral content for low cost.
Unique Allison regenerator experience is cited as follows: first gas turbine with rotating regenerator in production, thermal cyclic strength loss of ceramic disc materials and cyclic oxidation of metal disc materials, regenerator leakage as low as 3.4%, metal regenerator time versus temperature ignition limits of various metals, and damping of friction-induced torsional vibration of regenerator discs.