Creep analysis for Cross Wavy primary surface recuperator in 100 kw microturbine system

Recuperator is a compact and high efficiency heat exchanger working at high temperature and high pressure conditions. Creep deformation may occur in the passages of the compact primary sheet with the increase of the operation time. Inside the recuperator creep deformation causes the compressor discharge air passages to expand, thus restricting exhaust gas flow and increasing the turbine backpressure. This will deteriorate the flow and heat transfer performance of the recuperator, even affect the whole safe operation of the turbine system. In this paper, with the implicit Norton function, the creep deformation of CW recuperator (after working 40000 hours) is analyzed to prove the reliability of material, and it is found that the pressure difference between the air and the gas is the main reason to cause creep deformation of the sheet. The proper operation parameters, material and the best configuration of the passages are suggested.