Effect of Rotational Speed on Performance of Mixed Flow Pump as Turbine

Abstract

In order to research the flow characteristics of mixed flow pump as turbine (MF-PAT) with different rotation speeds, a hydraulic model of mixed flow pump was established based on a pumped storage power station. The k-ε turbulent model was used to simulate internal flow fields with three rotation speeds by SMPLEC algorithms. Subsequently, theoretical calculations and experiments were carried out to verify the precision of numerical simulation. The results showed that the rotation speed of MF-PAT has a significant impact on its performance. Both numerical calculations and experimental test presented that all efficiency curves consist of ascending and descending stages, while the shaft power and head increase nonlinearly from 1000 to 2000 r/min. When the MF-PAT deviates from the rated environment, increase in speed is positive to the energy recovery efficiency in the high water period and negative in the dry season. This work could provide a reference for further study of MF-PAT.

The pump as a turbine: A review on performance prediction, performance improvement, and economic analysis

“…Most existing works focus on radial flow pumps as turbines [ 60 ] due to their lower cost and availability. Recent publications concentrate on studying flow features such as rotational speed [ 53 , 55 ], transient behavior [ 54 , 56 ], tip leakage flow [ [61] , [62] , [63] ], entropy production [ 60 , 64 ], and cavitation [ 65 , 66 ] in PATs. Furthermore, there are numerous research works focused on performance improvement [ 40 , 67 ], and a relatively small number of papers examine the economic analysis [ 61 , 62 ] of PATs.…”

Studi Pengaruh Kecepatan Putar Impeller Terhadap Performance Model Waterjet Propulsor

“…Penelitian perhitungan numerik dan eksperimen pada putaran 1000 rpm, 1500 rpm dan 2000 menemukan bahwa kecepatan putaran mempunyai pengaruh yang signifikan terhadap kinerjanya efesiensi maksimum sebesar ≈72%. Peningkatan kecepatan putaran lebih cocok untuk kondisi aliran besar, namun efisiensi maksimumnya tidak meningkat [23] penelitian serupa juga telah dilakukan dengan variasi putaran n = 750 rpm-2500 rpm [24]. Pada induser, pengaruh putaran menyebabkan kecepatan lintasan induser dan tekanan statis meningkat, distribusi tekanan statis tidak simetris dan kinerja anti-kavitasi pompa menurun seiring dengan peningkatan kecepatan putaran [25].…”

“…Ketika kecepatan pompa diatur, kurva karakteristik Q-H, daya dan NPSH berubah sesuai untuk kecepatan N. Konversi kecepatan dilakukan melalui persamaan afinitas [2], [23], [39].…”

Characterization of a Commercial Axial Flow PAT Through a Structured Methodology Step-by-Step

“…2. Turbomachine selection for (a) traditional turbines [11] and (b) PATs [12] In the literature, numerical and CFD studies have been applied to radial [17][18][19][20][21][22], mixed [23,24], and axial [25][26][27][28][29][30][31][32] centrifugal pump as turbine, as well as in a review article [33], where the behavior of pressure, velocity, and the experimental characteristic curve have been validated. On the other hand, the study of the radial Flow PAT from the manufacturer's curve has been shown to predict the site conditions in turbine mode for specific velocities of 9-65 (rpm m 3/4 s -1/2 ) [34,35]; Similarly, another study was based on numerical correlations employing a flowchart.…”