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| Application of entropy production method to centrifugal pump energy loss evaluation |
| ZHANG Yongxue, HOU Hucan, XU Chang, HE Wenxuan, LI Zhenlin |
| College of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing 102249, China |
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Abstract To accurately calculate the hydraulic loss of centrifugal pump and its location, improve the hydraulic performance and avoid the limitations of traditional method based on pressure drop analysis, the local entropy production method was introduced in this study on energy consumption evaluation of centrifugal pumps. The whole steady flow passage of centrifugal pump was numerically simulated based on Reynolds stress turbulent model and energy equation model, and then the local entropy production terms were defined by self-definition field functions. Taking the cases of pipe flow for air and water as example, the results calculated by the local entropy production method were highly consistent with those calculated by Darcy law, pressure drop method and energy balance method, indicating that the local entropy production method established is reliable. Meanwhile, the calculation for centrifugal pump shows that the impeller and volute casing are the main domains generating entropy production, and the irreversible energy loss generated mainly cover wall entropy production and turbulent entropy production and in the design flow condition, these two occupy 48.61% and 47.91% of the whole respectively at the most. Above all, the energy loss by the entropy production method have some errors but basically accord with those by the traditional method, indicating that this entropy production me-thod is feasible in centrifugal pump irreversible energy loss evaluation.
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Received: 18 December 2015
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