Air–Hydrogen Heat Exchangers for Advanced Space Launchers

摘要

This paper deals with air–hydrogen heat exchangers intended to provide in-flight oxygen collection capability to anreusable or semireusable two-stages-to-orbit launcher with an oxygen collection phase in supersonic cruise atnMach 2.5. It aims to present a theoretical but mainly technological and experimental feasibility study of heatnexchangers sufficiently efficient and reliable to suit the extreme requirements of this application. Two precoolers ofntwo different types (shell and tubes, and plate and fins) have been selected and designedwith the objective of fulfillingnall constraints of the concept in terms of performance, leak tightness, reliability, compactness, etc. This designnprocess has been validated with four subscaled breadboards (two of each type) tested on two test benches (fornperformance and leak tightness), developed by Belgium and Spain, in on-design and off-design conditions. All thesenresults highlight the suitability of the new technologies given the extreme requirements of the concept. An optimumndesign for each technology is recommended considering its proper advantages and disadvantages. An innovativenprecooler technology is presented and tested.