Water pump impeller design & pumping efficiency
Posted: Sun Nov 10, 2019 9:55 am
I have just noticed a major difference between my old water pump and the new one. The impeller design is very different - see the pictures. The new one is very crude in terms of the impeller blades compared to the old one, although closer to the original (looking at the workshop manual). The reason for changing the pump was a failure of the long sleeve bearing after many miles, but the engine has never suffered from overheating.
The difference between the designs is striking, with curved blades on the old impeller, compared to flat/straight blades in the new one. This is important because curved blades improve the efficiency of pumping (in terms of volume per revolution) significantly. Technically, flat bladed impellers are more suited to mixing applications, with curved impellers suitable for pumping applications.
Does anyone have any ideas why the efficiency of TC water pumps is hobbled in this way? I for one would prefer more circulation of coolant!
Jeremy
The difference between the designs is striking, with curved blades on the old impeller, compared to flat/straight blades in the new one. This is important because curved blades improve the efficiency of pumping (in terms of volume per revolution) significantly. Technically, flat bladed impellers are more suited to mixing applications, with curved impellers suitable for pumping applications.
Does anyone have any ideas why the efficiency of TC water pumps is hobbled in this way? I for one would prefer more circulation of coolant!
Jeremy