COOLING SYSTEMS USED IN IC ENGINES

When the air fuel mixture is ignited and combustion takes place at 2500*C for producing power inside an engine the temperature of the cylinder, cylinder head , piston and valve, continuous to raise when the engine runs.

It these parts are not cooled by some means then they are likely to get damaged and even melted. The piston may cease inside the cylinder. To prevent this, the temperature of the parts around the combustion chamber is maintained as 200*C to 250*C. Too much of cooling will lower the thermal efficiency of the engine. Hence, the purpose of the cooling is to keep the engine at its most efficient operating temperature at the engine speeds and all driving conditions. The cooling system is so designed that it prevents cooling until the engine reaches to its normal operating temperature. When the engine warms up the cooling system will begin to function. It cools rapidly when the engine is too hot and it cools slowly or not at all when the engine is cold or warming up. Thus, the duty of the cooling system is to keep the engine from getting too hot-not to keep it cool.

Types Of Cooling Systems :

1. Air Cooling or Direct Cooling.

2. Water cooling or indirect cooling.

a) Thermosyphon cooling

b) Pump circulation cooling.

3. Liquid Cooling.

4. Pressure Sealed Cooling.

5. Steam Cooling or Evaporative Cooling.

Generally, for automobile engines air-cooling and water-cooling are used.

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ELECTRICAL COMPARATORS AND ITS WORKING

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Mechinopedia For Mechanical Engineers

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