Evaluation of Potential Environmental Control Systems for Mach 3 Troop Transport Aircraft

Abstract

Abstract : The purpose of this report was to select potential environmental control systems (ECS) to be used in the 256 seats supersonic troop transport cruising at Mach 3. Those systems under consideration were (1) bootstrap air cycle environmental control system with an air cooled compartment wall, (2) semiclosed bootstrap air cycle environmental control system with an air cooled compartment wall, (3) semiclosed vapor cycle environmental control system with an air cooled compartment wall, (4) semiclosed vapor cycle environmental control system with a liquid cooled compartment wall, and (5) semiclosed vapor cycle environmental control system with a liquid cooled compartment wall and without a water boiler. The last four of the five systems recirculated approximately 50% of the compartment air (250 lb/min) and the rest of the compartment air was exhausted through an ECS heat exchanger. Two types of compartment walls were examined: an air cooled wall and a liquid cooled wall. Fuel was used as the primary heat sink in all the systems. The maximum internal heat load under which each system was analyzed was the same, 158,000 Btu/hr. The total combined maximum internal and external heat load for the first four systems was 417,000 Btu/hr and the fifth system, 577,000 Btu/hr. Except for the liquid cooled wall, the systems selected for consideration represent a number of different types of basic systems that have appeared previously for supersonic aircraft. The main criteria used for selecting an environmental control system was based on the weight penalty considerations.