A waterpump for a 7L deisel engine application has inspired this study.  The baseline design fits between the gear cover on the front of the engine and the radiator fan, a rather narrow space.

Our first modification for the volute targets the sudden expansion in the volute near the outlet duct. We do this by modifying the volute geometry to match the outlet duct in a smooth way.  Then we resize the volute to match, with a bias towards a larger volute than the Baseline case. We call this case the Radially Big Volute.

The point of this case is to see any performance advantages to making the volute as large as necessary to match the outlet duct.  The inlet housing, impeller, and outlet duct portions of this case are identical to the Baseline case.
 

• View the Geometry of the pump.
• View the Mesh of the pump.
• View the Mesh of the Volute and Impeller.
• View The Change in size from the Baseline Pump

• 0kPa
• 75kPa
• 175kPa
• 212kPa

• System mass flow at large pressure heads (>175 kPa) is lower than the Baseline Case. At smaller pressure head's this volute has an advantage over the Baseline Case.
• Mass flow from one blade passage to the next is quite uniform for the 75 kPa case.
• Pressure distribution in the impeller is radial; there is little variation from one blade passage to the next at 75kPa.
• Flow distribution in the volute is quite uniform for the 75 kPa case.
• Pressure minimum in the blade passage near the cutoff causes cavitation for the 75 kPa case (inlet gauge pressure of 45kPa); this cavitation is weaker than the Baseline case, but stronger than the Simplified Inlet case.
• Mass flow from one blade passage to the next is not as uniform for the 175 kPa case.
• Utilization of the volute and impeller is more uniform for the 75 kPa case than for the 175 kPa case.   This is the opposite trend as that seen in the Baseline and Simple Inlet cases.