Exam Question
Explain with a simple line sketch, a main engine jacket cooling automatic control system capable of maintaining the jacket water temperature within close limits during wide changes in engine load. (16)
Class 4 (4th Engineer)
MET
📅 Jun 2024
Reference Answer
### **Part 1: Main Engine Jacket Cooling System (High Temperature - HT System)**
The main engine jacket cooling water system is a closed-loop, high-temperature fresh water circuit designed to remove excess heat from the principal combustion chamber components. Maintaining the correct operating temperature is critical for ensuring efficient combustion, proper liner lubrication, and preventing both thermal stress and cold corrosion.
#### **1. Principle of Operation**
The system circulates treated fresh water through the engine's cylinder liners, cylinder heads, and sometimes the turbocharger casing to absorb waste heat. This heated water is then passed through a central cooler where the heat is transferred to the LT (Low Temperature) Central Cooling Water system, which ultimately dissipates the heat overboard via the main sea water pumps.
The main engine jacket cooling water system is a closed-loop, high-temperature fresh water circuit designed to remove excess heat from the principal combustion chamber components. Maintaining the correct operating temperature is critical for ensuring efficient combustion, proper liner lubrication, and preventing both thermal stress and cold corrosion.
#### **1. Principle of Operation**
The system circulates treated fresh water through the engine's cylinder liners, cylinder heads, and sometimes the turbocharger casing to absorb waste heat. This heated water is then passed through a central cooler where the heat is transferred to the LT (Low Temperature) Central Cooling Water system, which ultimately dissipates the heat overboard via the main sea water pumps.
Full answer on MeoMock — surveyor-grade reference answers for 7,000+ written exam questions.
Prepare on Android — MeoMock on Google Play