Investigation On Primary Surface Heat Exchangers For Intercooled-cycle Aero-engines

In modern high thrust-to-weight ratio aero-engines, intensive cooling technology of hot components is facing a very huge task. In this case, the intercooling technology becomes more popular because it can help reduce the inlet air temperature of high pressure compressor and gas turbine, which thus improves the quality of cooling air. For intercooled-cycle aero-engines, the structure design and installation of intercooling heat exchangers are the key technologies to fully embody its superiority. Since domestic research on intercooled-cycle engines is still in its infancy, the design of intercooled-cycle heat exchanger lacks necessary research basis. Therefore, the study on high-efficiency, low-resistance heat exchanger for intercooled-cycle aero-engines is of great importance for engineering applications.This article mainly focuses on the design of heat exchanger for intercooled-cycle aero-engines. Firstly, the physical models and numerical simulation methods of typical Cross Corrugated(CC), Cross Undulated(CU), and Cross Wavy(CW) primary surface heat exchangers were described in detail. With the help of computational fluid dynamics(CFD) methods, periodic boundary conditions were applied on the inlets and outlets of a unitary cell for the purpose of removing entrance effects and the turbulence model validation work was carried out as well. Next, based on numerical simulation results, the enhanced heat transfer principles in a unit cell were explained and the effects of typical stucture parameters on internal flow field, velocity field, temperature field and comprehensive performance of unitary cells were analyzed. On that basis, the design scheme of intercooling heat exchanger matrix was put forward after drawing lessons from foreign mature intercooler structure layout. The heat exchanger matrix was simplified as porous medium zone and the fluid pressure loss was compared and analyzed in differect operating conditions and V-shaped angles. Numerical results have shown that when the V-shaped angle decreases, the pressure drop between inlet and outlet rises that results in larger pressure loss.The results in this article may have a certain reference significance on the design and optimization of intercooling primary surface heat exchanger for intercooled-cycle aero-engines.