Advanced Heat Exchanger (HEX) Scaling Methodologies for High-Performance Aircraft

The well-known consequence of high-performance, low-observable, more-electric strike aircraft is the increased thermal loading that can ultimately threaten mission-critical components. The ability to efficiently transport the resulting waste energy to onboard coolants is now understood to be an airframe-level design point that should be considered with a priority approaching that of thrust, range, or rate of climb. In this regard, attention has been focused on advanced heat exchanger technologies which offer the potential for increased volumetric heat transfer capacity. PCKA proposes to simulate candidate heat exchangers by discarding flow approximations in favor of 3-D solutions of the Navier-Stokes and energy equations in both solid and liquid domains. Wide parametric studies can be performed, generating performance curves for several candidate heat exchangers, which will include the effect of design modifications on resultant heat exchange capacity and pressure drops. With the acquisition of physics-based performance data, a methodology is outlined by which the CFD can be integrated into a system-level model, where “CFD-in-the-loop” capability can truly contribute to an airframe-wide virtual design tool. The proposed tool is inherently general to non-specific airframes, but can be applied directly in thermal management models already developed for the F-22 and F-35 systems.