Expanding the Limits on Engines and Vehicles Imposed by Circulating Liquid Engine Cooling Systems

The operational limits of the cooling system for a liquid cooled internal combustion engine are also limits on the engine's power, fuel economy and air quality possibilities. When coolant temperatures in a traditional liquid cooled engine approach the saturation temperature of water, optimum engine settings must be degraded to prevent detonation. Aerodynamic vehicle designs that require down-sized radiators or that specify smaller openings for the intake of cooling air present the difficulty of maintaining coolant temperatures low enough to avoid the need to degrade engine efficiency and performance. This paper discusses the nature of the limits imposed by traditional liquid cooling and describes a cooling process that circulates a non-pressurized, non-aqueous, high boiling point coolant and which uses a condenser to prevent coolant loss, to expand these limits.