Numerical Simulation Of Centrifugal Pump Research Articles

Numerical Simulation of Centrifugal Pump and Effect of Impeller Geometry on Its Performance

In the presented paper, the effect of impeller geometric parameters on the performance of centrifugal pump has been investigated. This study was performed for different flow rates and rotational speeds, allowing to obtain the performance curve for the centrifugal pump. Three dimensional computational fluid dynamic simulation of the impeller and volute for a centrifugal pump has been performed using ANSYS CFX software (a high-performance computational fluid dynamics software tool that delivers reliable and accurate solutions). The pump has an outside impeller diameter of 205 mm, impeller outlet width of 16 mm, rotational speed 1450 rpm, seven impeller blade and a specific speed of 28. By increasing the impeller outer diameter and outlet width, both net head and power consumed are increased. In addition, it was noticed that the best efficiency point (BEP) was achieved at volume flow rate higher than design flow rate. The performed simulations indicated that; by changing the impeller outer diameter from 200 mm to 210 mm, the flow rate of BEP increases about by 14.7%. By changing the impeller outlet width from 14 mm to 18 mm, the flow rate of BEP increased by about 9%, and the efficiency of BEP reduced by approximately 0.5%. It was also noticed that, increasing the rotational speed will cause an increase in the net head and consumed power. An increase of 13.8% for the flow rate of BEP was observed when changing the rotational speed from 1400 rpm to 1500 rpm, with the same BEP.

Performance Analysis of Centrifugal Pump at Different Operating Mode

The aim of this research is to perform numerical simulation of centrifugal pump and PATs mode to analyse its cavitation characteristics and NPSHr at different operating conditions. It was found that maximum efficiency at design discharge for the PAT is about 2 % less than the efficiency in pump mode. It is observed that the efficiencies increase steadily on increasing the discharge from 8.88 kg/s to 14.8 kg/s. in both pump and turbine mode. Thereafter the rate of increase in efficiency becomes very less when increase in discharge to 17.76 kg/s. Maximum efficiency of 59.49 % being achieved at 14.8 kg/s.

Influence of clearance model on numerical simulation of centrifugal pump

Computing models are always simplified to save the computing resources and time. Particularly, the clearance that between impeller and pump casing is always ignored. But the completer model is, the more precise result of numerical simulation is in theory. This paper study the influence of clearance model on numerical simulation of centrifugal pump. We present such influence via comparing performance, flow characteristic and pressure pulsation of two cases that the one of two cases is the model pump with clearance and the other is not. And the results show that the head decreases and power increases so that efficiency decreases after computing with front and back cavities. Then no-leakage model would improve absolute velocity magnitude in order to reach the rated flow rate. Finally, more disturbance induced by front cavity flow and wear-ring flow would change the pressure pulsation of impeller and volute. The performance of clearance flow is important for the whole pump in performance, flow characteristic, pressure pulsation and other respects.

Numerical Simulation and Orthogonal Design Method Research Effect of Splitter Blade's Main Geometry Factors on the Performance of Pump as Turbine

In order to research the effect of splitter blades main geometry factors on the performance of pump as turbine, the L9(34)orthogonal design scheme has been developed based on four factors which contain the blades circumferential biasing degrees, the outlet deflection angle, the outlet diameter and the number of blade. According to this design scheme, numerical simulation of centrifugal pump (ns48) as turbine has been done. By range analysis of computational results, the best design scheme of splitter blades and the level of each factor for the primary and secondary order of turbine efficiency (the outlet deflection angle, the outlet diameter, the number of blade, and blades circumferentially biasing degrees) are obtained. The internal characteristics analysis was done on centrifugal pump (ns48) as turbine at its optimal operating conditions. The results shows, compared with conventional impeller, that the internal velocity and pressure field distribution using the design scheme of composite impeller is more reasonable.

Effects of computational grids and turbulence models on numerical simulation of centrifugal pump with CFD

In order to verify accurately the effects of computational grids and turbulence models on CFD numerical simulation of centrifugal pump, the calculation results of the different mesh numbers coupling with five kinds of turbulence models are compared. These parts of models (e.g. wear ring and tongue) are meshed with the local refinement technology. At design condition, with CFX software on the Dawning TC3600 parallel computer cluster, the calculation results of phase coupling six different mesh numbers from 1 million to 25 million with five different turbulence models (K-Epsilon, SSG Reynolds Stress, K epsilon EARSM, RNG K-Epsilon, K-Omega) are used to make performance prediction and to analyze the internal flow field. And the comparison between performance prediction results and experimental results are analyzed. It is confirmed that the calculation results are quite different with different turbulence models, and the result under K epsilon EARSM model is better than the others. And it shows that the internal flow in centrifugal pump is depicted more perfect with the increase of mesh numbers.

Examine Applicability of the RANS and LES Method on Numerical Simulation of Centrifugal Pump

In order to examine applicability of the Reynolds-Averaged Navier-Stokes （RANS）using Reynolds Stress equation Model (RSM) and the Large Eddy Simulation (LES) in numerical simulation of centrifugal pump, a series of 3D numerical simulation at the design point and at six off-design points were carried out with the two methods. The object is based on IS80-65-160 centrifugal pump. According to the results obtained, head, shaft power, efficiency of pump were calculated, the simulated performance curves of a centrifugal pump is processed. The simulated performance curves of a centrifugal pump were compared with the experimental performance curves. It was confirmed that RANS were suitable for the numerical simulation of the internal flow inside a centrifugal pump. But the result of LES is not very good if the same gambit which is suitable for RANS was used. Therefore, the computer resources, not propose the Large Eddy Simulation (LES) method in numerical simulations of centrifugal pump.

Flow Numerical Simulation of Centrifugal Pump with Splitting Blades Based on RE

The structure of the centrifugal pump with splitting blades is complex, and the law of the internal flow is not fully grasped. Therefore Reverse Engineering (RE) and numerical simulations of Computational Fluid Dynamics (CFD) are adopted to study the centrifugal pumps with splitter blades. In this process, the law of velocity and pressure distribution of internal flow about the centrifugal pump with splitter blades is preliminary disclosed. In addition, performance prediction was carried out in centrifugal pumps. Comparing to the calculation curve and text characteristic curve, it’s obvious that simulation results are in good agreement with experimental results. The results verify the reliability and feasibility of the research method.

Experiment and numerical simulation of centrifugal pump with different wrap angle

Centrifugal impellers C1,C2 and C3 are designed by using of three-order blade profile with the same basic geometry, such as radius,blade width and angle in the inlet and outlet,the number of the blades,and the designed rotating speed is also the same.The wrap angle of C1,C2 and C3 is 59°,75°and 91°respectively.The profile of impeller C1 is very close to the ones of traditional single-arc.The test results indicate that the best efficiency of C2 is 1.28%,1.43% higher than C1 and C3 re- spectively.By numerical simulation at the designed flow rate, the distribution of the relative velocity and load in the impeller is obtained.In the impeller C1 there is recirculation flow and load distribution in different passage is different.The study indicates that there is a best wrap angle and the single-arc is not the best blade profile.