Why does an increase in lubricant temperature lead to a decrease in pressure?
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Why does an increase in lubricant temperature lead to a decrease in pressure?
As the temperature of the lubricating oil increases, its viscosity decreases, and its density also decreases. According to the PGH formula, the outlet pressure drops as a result
What was said upstairs is correct; it has to do with viscosity and density.
An increase in temperature inevitably leads to a decrease in pressure, as lubrication pumps are generally gear pumps or triple-screw pumps. These two types of pumps belong to the category of positive-displacement pumps, and the outlet pressure of such pumps depends on the level of back pressure. When the temperature rises, the viscosity decreases, which reduces the resistance in the path after the pump’s outlet; as a result, the back pressure drops, and consequently the outlet pressure of the pump also decreases. If the low level is quite severe, then the cooling effect needs to be considered, or a self-acting pressure control valve can be used for regulation
As the temperature rises, the viscosity decreases, so the pressure at the pump outlet drops
As the temperature rises, the viscosity decreases