A Multi-Design Point Sizing Methodology for Environmental Control Systems

Abstract

The environmental control system, which is to provide cabin air supply, conditioning, and pressurization, is the largest consumer of the secondary power in the aircraft. The impacts of the environmental control system designs have been studied for a long time. However, there is not a clear design guideline for it. Many studies have designed or optimized the environmental control system for a single point which was important in terms of vehicle or mission fuel economy. Some other researchers chose the most critical condition for sizing, such as the hot day and ground condition, or hot day with one engine failed. Some research also pointed out that the cooling efficiency can be greatly influenced when operation point is far from its design point. Therefore, a design guideline of the environmental control system is needed. To fill this gap, this paper proposes a multi-design point sizing methodology which sizes the environmental control system based on performance requirements of multiple points instead of those for a single point. This methodology will guarantee that all the requirements through the mission will be satisfied, and the efficiency will not be influenced much when the operation condition moves.