Introduction To Cooling System Design

tem that will also maintain adequate cooling margins ... have low drag for a 10,000' cruise, but the engine .... So far we have determined the flow rate needed to ...
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Introduction To Cooling System Design by DAN BOND Renaissance Designs 26O3b Trailside Dr. Austin, TX 78704

It is generally easy enough to cool a modern aircraft engine for a single flight condition. It's also fairly easy to design

very difficult for an individual to get them. In the absence of this data, or sophisticated test equipment, the homebuilder must rely on several "rules of thumb". These guidelines will be discussed in a future article. For the moment, let's assume we know the air flow requirements of the engine. With this information we know

a very low drag cooling system. The problems come from the desire to combine these two easy tasks in one system that will also maintain adequate cooling margins on the inevitable climb from sea level on a very hot day. With this series of articles, we hope to provide some of the basic concepts needed to design an effective and efficient cooling system. This first article provides an overview of the cooling system and points out some of the problems in developing a good design. The graphs presented are meant only to demonstrate the trends of the variables being studied, and do not represent any actual design.

pressure differential of 7 psf must be provided. At 20,000', this pressure requirement is increased to 16 psf. Although charts of this sort are available from engine manufacturers, it is usually

Typical Engine Cooling Charts

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What Does The Cooling System Do? The cooling system has a very simple task: Provide enough air to the engine and auxiliary coolers to maintain safe operating temperatures at all points in the flight envelope. It is not enough to have low drag for a 10,000' cruise, but the engine must also be cool during a prolonged maximum performance climb

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