Evaporating Coolant for On-Board Cooling Systems with Direct Condensation through Ambient Air

Fachgebiet:

Klima- und Kühlungssysteme

Jahr:

2008

Art der Publikation:

Paper

Autoren:

Steve Adeyefa, F. Thielecke, Udo B. Carl

Buchtitel:

26th Congress of the International Council of Aeronautical Sciences

On-board cooling systems using carbon dioxide are of interest due to possible advantages in installation space and system mass. Here, a new system architecture is introduced using CO2 as an evaporating coolant in a secondary distribution cycle condensed by a primary vapour cycle for ground operations and by ambient air during flight. Deactivation of active vapour cycle cooling enables benefits regarding power consumption and availability. Experimental investigations regarding ground operation at high ambient temperatures are discussed outlining the evaporating coolant cycle characteristics. Based on the derived system behaviour and relevant boundary conditions, a simulation model of the ambient heat exchanger is used to determine the performance envelope and feasibility of direct condensation, based on an automotive heat exchanger without optimisation for the intended application.