Conceptual design of a two-pass cross-flow aeroengine intercooler

Abstract

Establishing an optimal intercooled aeroengine constitutes a coupled problem where the conceptual design of the intercooler and the engine has to be considered simultaneously. The heat transfer and pressure loss characteristics will depend on the choice of the intercooler architecture. Hence, to be able to optimize the performance of an intercooled aeroengine, the performance characteristics of a given intercooler architecture has to be known in the parameter range anticipated for the aeroengine optimization. Here, the conceptual design of a tubular two-pass crossflow intercooler architecture intended for a turbofan aeroengine application is presented. The internal flow is simulated applying a porous media model for the intercooler tubes, whereas the connecting ducts are analyzed with threedimensional simulations allowing the assessment of a number of design solutions. The external flow is treated with two-dimensional simulations investigating the external pressure loss and heat transfer characteristics of the two elliptical tube stacks. The intercooler performance is then generalized by developing a reduced order correlation covering a parameter range anticipated for a turbofan conceptual design optimization. The paper constitutes a first effort to establish an open literature complete set of correlations for the prediction of aeroengine intercooler performance.

Performance of a Supercritical CO2 Bottoming Cycle for Aero Applications

“…Care has to be taken during the design of the cold-side free flow area, to ensure the design adheres to the Reynolds number limits stated in [29]. From the designs investigated by Zhao et al in [30], the option featuring a radial tube spacing of d b = 2b and an axial tube spacing of d a = a was chosen, where a and b represent the large and small axes of the elliptic tube profile. The aspect ratio of the tube cross-section is fixed in all studies to a b = 8 (see Figure 4 for reference).…”

“…Note, the involute spiral heat exchanger was originally designed as an intercooler and has been repurposed for this study. The detail available on the design and performance of the heat exchanger in [29][30][31] enabled it to be adapted for the MHX duty with turbine exhaust gases and S-CO2. All correlations contained in [29,30] were originally derived from CFD experiments featuring air as the medium on both sides.…”

“…Note, the involute spiral heat exchanger was originally designed as an intercooler and has been repurposed for this study. The detail available on the design and performance of the heat exchanger in [29][30][31] enabled it to be adapted for the MHX duty with turbine exhaust gases and S-CO 2 . The dependency of the thermal efficiency of the bottoming cycle on the design point isentropic efficiencies of the turbine and compressor is illustrated in Figure 2b.…”

“…This makes them non-ideal for application to S-CO2. However, All correlations contained in [29,30] were originally derived from CFD experiments featuring air as the medium on both sides. This makes them non-ideal for application to S-CO 2 .…”

Off-Design Behavior Analysis and Operating Curve Design of Marine Intercooled Gas Turbine

“…Optimization and assessment of a cross-flow heat exchanger for advanced intercooled cycle aero engines were carried out using CFD method by Kim et al [7]. The correlation between heat transfer and loss characteristics has been emphasized during conceptual design of a two-pass cross-flow aeroengine intercooler [8]. Zhao et al [9] studied the effects of different materials and different coolants on intercooler performance and developed intercooler optimization by using simulated annealing algorithm.…”