In actual use, there is a misconception that the lower the coolant temperature of a diesel generator, the better. In fact, we have clear requirements for the use of diesel engine coolant temperature. Some operators prefer to adjust the coolant temperature very low. Some are close to the lower limit of coolant temperature, while others are lower than the lower limit of coolant temperature. They believe that if the coolant temperature is low, the water pump will not experience cavitation, the coolant will not be interrupted, and there is a safety factor in use. In fact, as long as the coolant temperature does not exceed 95 ℃, there will be no cavitation and the coolant will not be interrupted. On the contrary, if the coolant temperature is too low, it is very harmful to the diesel engine.
As the viscosity of the oil in the lubrication system increases, the running resistance of the parts increases, leading to poor lubrication and increased wear between parts. For example, when the coolant temperature is 30 ℃, compared to the coolant temperature of 80-90 ℃, the wear of cylinder liners, pistons, and piston rings will increase by about 5 times.
2. Low coolant temperature, deterioration of combustion conditions in the diesel engine cylinder, poor fuel atomization, extended post combustion period, and rough operation of the diesel engine exacerbate the damage to components such as crankshaft bearings and piston rings, reducing power and economy.
3. The water vapor after combustion is prone to condensation on the cylinder wall, causing metal corrosion.
4. Unburned diesel will dilute the engine oil, resulting in poor lubrication effect.
5. Incomplete combustion of fuel can form gum, causing the piston ring to get stuck in the piston ring groove, causing the valve to get stuck, and reducing the pressure in the cylinder at the end of compression.
As the heat loss increases, the power of the diesel engine decreases and fuel consumption increases.
7. Poor fuel atomization, incomplete combustion, reduced power, and increased fuel consumption. If the coolant temperature is 40 ℃, the fuel consumption of the diesel engine will be about 10% more than 80 ℃. Therefore, the lower the temperature of the diesel engine coolant, the better. Generally controlled between 80-95 ℃.