Lightweight Recuperators for Small Turbine Engines

Turbine engines can significantly reduce fuel consumption by using a recuperator to heat compressor discharge air with heat from combustion exhaust gases. This increased fuel efficiency is offset by the weight and pressure losses added by the recuperator, so these must be minimized, especially for small turbine engines. An extremely compact recuperator was previously built for the Rolls Royce Model 250-20B small turbine engine; in testing, this recuperator achieved a 70% effectiveness with hot- and cold-side pressure loss/pressure ratios of 3% at a core weight of less than 38 lbs. In the proposed effort this work will be extended to a higher power version of the Model 250 series, with a significant reduction in core weight/dissipated power via improved modeling, incorporation of lightweight materials, and improved core designs.