Which one of the following cooling systems is used in large marine diesel engines?
Show Hint
1. Forced circulation is ideal for high heat dissipation.
2. Air cooling is generally for smaller engines.
3. Evaluate the system's ability to handle continuous heavy loads for marine applications.
- Thermosyphon
- Forced coolant circulation
- Evaporative
- Air circulation
The Correct Option is B
Solution and Explanation
Step 1: Importance of cooling in marine diesel engines. Large marine diesel engines operate under high loads and generate significant heat. Effective cooling is crucial to prevent engine overheating, ensure operational efficiency, and maintain engine longevity.
Step 2: Cooling methods analysis.
Thermosyphon (Option A): This passive cooling system relies on natural convection but is unsuitable for large marine engines due to its limited capacity.
Forced coolant circulation (Option B): This system uses pumps to circulate coolant actively through the engine and heat exchangers. It is efficient and commonly used in large marine diesel engines.
Evaporative cooling (Option C): This system is impractical for marine diesel engines as it would require constant replenishment of coolant.
Air circulation (Option D): Air cooling is more suited for smaller engines due to its lower efficiency in dissipating large amounts of heat.
Conclusion: Forced coolant circulation is the most effective and widely used cooling system in large marine diesel engines, corresponding to option \( \mathbf{(B)} \).
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