Feasibility of a Brayton Cycle Automotive Air Conditioning System

The goal of this work is to develop a preliminary analysis on the feasibility of using an alternative automotive air conditioning system based on the Brayton cycle, to be assembled using a turbocompression-intercooling system configuration available in the market. The first step of the analysis was a thermodynamic study to define the system capacity and parameters for selecting the system components. The next step was to select from turbocompressor maps a suitable model for the application, and to determine pressures/temperatures throughout the system in order to evaluate intercooler capacity and select a suitable model available in the market. The impact of the turbocompression system was also analyzed in engine performance. The proposed turbocompression system requires 1,7 kW from the engine, which is very similar to a conventional air conditioning system requirement. In terms of weight, this preliminary analysis indicated that the proposed system is about 1,0 kg heavier than the conventional system. The analysis indicated that the alternative system is about 56% more expensive than the conventional one, but on the other hand presents a 24% lower maintenance cost . Considering the results of the preliminary analysis, the proposed system is technically feasible for application in automotive air conditioning, but requires a design optimization process in order to reduce its weight and initial costs, which might allow lower maintenance costs to payback the alternative system.