Engine Cooling System of Military Combat/Tactical Vehicles

Military combat/tactical vehicles, such as tanks, are designed to be deployed and operated constantly in close proximity to the enemy fire. In order to provide sufficient protection for the engine and its vital systems, they are located in an almost completely enclosed and heavily armored compartment ventilated through highly restricted ballistic grilles. The space available for the cooling system in the engine compartment is limited. The heat rejection rate from various sources is high. The cooling air flow path is clumsy; repeated enlargements and reduction of the air flow sectional areas, complemented by possible bending and twisting, are common. The effective cooling air temperature is much higher than that of the ambient. All these factors alone make the cooling system designs of the subject vehicles quite different from that of the commercial vehicles, not to mention the severe military environment within which the cooling system must function properly.

This paper is a presentation of unclassified technical information directly related to the cooling system design of the subject vehicles. Severe military environment and its impact on the cooling system design are discussed. Characteristics of major components, such as ballistic grilles and their air resistance data, are presented. Typical arrangements of air flow path and liquid flow path are described. Basic design methods are discussed. Important references issued by various Army agencies are presented.