Sensitivity Solution of Off-Design Conditions in Centrifugal Pump
Date
2023-11
Authors
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Publisher
I.O.E. Pulchowk Campus
Abstract
Centrifugal pumps are most widely used pumps in industry and household usage for fluid flow. During usage of pump, pump speed and discharge may need to be varied. Also during continuous usage of pump, different physical defects may arise. These conditions would create off-design conditions in pump which are studied in this paper. The paper outlines a technique for efficiently obtaining the numerical solution of a pump operating in off-design conditions by leveraging the solution obtained under design conditions. This method is referred to as a “sensitivity solution”, wherein small parameter adjustments are made, and simulations are conducted starting from an already converged solution. Test was done for change in impeller speed and it was found that for one percentage change, sensitivity solution was obtained in one-fourth time compared to its baseline simulation. For the flow rate variation, for two percentage change, sensitivity solution is obtained in one-fifth time. Results support use of sensitivity method for solving flows for variations up to ten percent. Variation in output parameter is seen to be higher in case of speed changes compared to the flow rate.
Description
When sensitivity simulation method is tested for defect depth in impeller blade, solution is obtained in one-tenth time compared to baseline simulation for up to 60% increase in defect depth. In case of speed and flow rate deviation, sensitivity simulation time is increasing as deviation from base case is increasing while for defect depth, the sensitivity simulation time do not change significantly for depth changes tested
Keywords
Sensitivity Solution,, Off-Design Conditions,, Centrifugal Pump