scholarly journals Numerical Identification of Key Design Parameters Enhancing the Centrifugal Pump Performance: Impeller, Impeller-Volute, and Impeller-Diffuser

2011 ◽  
Vol 2011 ◽  
pp. 1-16 ◽  
Author(s):  
Massinissa Djerroud ◽  
Guyh Dituba Ngoma ◽  
Walid Ghie

This paper presents the numerical investigation of the effects that the pertinent design parameters, including the blade height, the blade number, the outlet blade angle, the blade width, and the impeller diameter, have on the steady state liquid flow in a three-dimensional centrifugal pump. Three cases were considered for this study: impeller, combined impeller and volute, and combined impeller and diffuser. The continuity and Navier-Stokes equations with the k-ε turbulence model and the standard wall functions were used by means of ANSYS-CFX code. The results achieved reveal that the selected key design parameters have an impact on the centrifugal pump performance describing the pump head, the brake horsepower, and the overall efficiency. To valid the developed approach, the results of numerical simulation were compared with the experimental results considering the case of combined impeller and diffuser.

2013 ◽  
Vol 2013 ◽  
pp. 1-15
Author(s):  
Nicolas La Roche-Carrier ◽  
Guyh Dituba Ngoma ◽  
Walid Ghie

This paper deals with the numerical investigation of a liquid flow in a first stage of a multistage centrifugal pump consisting of an impeller, diffuser with return vanes, and casing. The continuity and Navier-Stokes equations with the k-ε turbulence model and standard wall functions were used. To improve the design of the pump's first stage, the impacts of the impeller blade height and diffuser vane height, number of impeller blades, diffuser vanes and diffuser return vanes, and wall roughness height on the performances of the first stage of a multistage centrifugal pump were analyzed. The results achieved reveal that the selected parameters affect the pump head, brake horsepower, and efficiency in a strong yet different manner. To validate the model developed, the results of the numerical simulations were compared with the experimental results from the pump manufacturer.


Author(s):  
Zhang Lisheng ◽  
Jiang Jin ◽  
Xiao Zhihuai ◽  
Li Yanhui

In this paper numerical simulations were conducted to analyze the effects of design parameters and distribution of balancing-hole on the axial-force of a partial emission pump. The studied pump is a single stage pump with a Barske style impeller. Based on the original impeller, we designed 7 pumps with different balancing-hole diameters and the partial emission pump equipped with different impellers were simulated employing the commercial computational fluid dynamics (CFD) software Fluent 12.1 to solve the Navier-Stokes equations for three-dimensional steady flow. A sensitivity analysis of the numerical model was performed with the purpose of balancing the contradiction of numerical accuracy and the cost of calculation. The results showed that, with increasing of the capacity, the axial force varies little. The diameter of the inner balancing-hole plays a dominant role of reducing axial-force of partial emission pump, the axial-force decreases with increasing of inner balancing-hole diameter on the whole range of operation, the axial-force of impeller without inner balancing-hole is approximately 3 times larger than that of impeller with inner balancing-hole. While the diameter of outer balancing-hole has a reverse effects compared with that of inner balancing-hole. With increasing of outer balancing-hole, the axial force increases accordingly.


Author(s):  
Hyeonmo Yang ◽  
Sung Kim ◽  
Kyoung-Yong Lee ◽  
Young-Seok Choi ◽  
Jin-Hyuk Kim

One of the best examples of wasted energy is the selection of oversized pumps versus the rated conditions. Oversized pumps are forced to operate at reduced flows, far from their highest efficiency point. An unnecessarily large impeller will produce more flow than required, wasting energy. In the industrial field, trimming the impeller diameter is used more than changing the rotation speed to reduce the head of a pump. In this paper, the impeller trimming method of a mixed-flow pump is defined, and the variation in pump performance by reduction of the impeller diameter was predicted based on computational fluid dynamics. The impeller was trimmed to the same meridional ratio of the hub and shroud, and was compared in five cases. Numerical analysis was performed, including the inlet and outlet pipes in configurations of the mixed-flow pump to be tested. The commercial CFD code, ANSYS CFX-14.5, was used for the numerical analysis, and a three-dimensional Reynolds-averaged Navier-Stokes equations with a shear stress transport turbulence model were used to analyze incompressible turbulence flow. The performance parameters for evaluating the trimmed pump impellers were defined as the total efficiency and total head at the designed flow rate. The numerical and experimental results for the trimmed pump impellers were compared and discussed in this work.


Author(s):  
Fahua Gu ◽  
Mark R. Anderson

The design of turbomachinery has been focusing on the improvement of the machine efficiency and the reduction of the design cost. This paper presents an integrated design system to create the machine geometry and to predict the machine performance at different levels of approximation, including one-dimensional design and analysis, quasi-three-dimensional-(blade-to-blade, throughflow) and full-three-dimensional-steady-state CFD analysis. One of the most important components, the Reynolds-averaged Navier-Stokes solver, is described in detail. It originated from the Dawes solver with numerous enhancements. They include the use of the low speed pre-conditioned full Navier-Stokes equations, the addition of the Spalart-Allmaras turbulence model and an improvement of wall functions related with the turbulence model. The latest upwind scheme, AUSM, has been implemented too. The Dawes code has been rewritten into a multi-block solver for O, C, and H grids. This paper provides some examples to evaluate the effect of grid topology on the machine performance prediction.


Author(s):  
Hong Won Kim ◽  
Jae Hoon Chung ◽  
Hyo Seong Lee ◽  
Min Ouk Choi

The primary design goal of a compressor is focused on improving efficiency. Secondary objective is to widen the compressor’s operating range. This paper presents a numerical and experimental investigation of the influence of the bleed slot to enlarge operating range for the 1.2MW class centrifugal compressor installed in a turbocharger. The main design parameters of the bleed slot casing are upstream slot position, inlet pipe slope, downstream slot position and width. The DOE (design of experiment) method was carried out to optimize the casing design. Numerical analyses were done by the commercial code ANSYS-CFX based on the three dimensional Reynolds-averaged Navier-Stokes equations. From the analysis, as the downstream slot position and width are smaller and upstream position is located away from impeller inlet, efficiency and pressure ratio are increased. Experimental works were done with and without the bleed slot casing. The simulation results were in good agreement with the test data. In case without the bleed slot casing, the surge margin value came out to be only 11.8% but with the optimized bleed slot design, the surge margin reached 23%. Therefore, the surge margin increase of 11.2% was achieved.


2013 ◽  
Vol 694-697 ◽  
pp. 56-60
Author(s):  
Yue Jun Ma ◽  
Ji Tao Zhao ◽  
Yu Min Yang

In the paper, on the basis of three-dimensional Reynolds-averaged Navier-Stokes equations and the RNG κ-ε turbulence model, adopting Three-dimensional unstructured grid and pressure connection the implicit correction SIMPLEC algorithm, and using MRF model which is supported by Fluent, this paper carries out numerical simulation of the internal flow of the centrifugal pump in different operation points. According to the results of numerical simulation, this paper analyzes the bad flow phenomena of the centrifugal pump, and puts forward suggests about configuration perfected of the centrifugal pump. In addition, this paper is also predicted the experimental value of the centrifugal pump performance, which is corresponding well with the measured value.


Author(s):  
Lu-Lu Zheng ◽  
Hua-Shu Dou ◽  
Wei Jiang ◽  
Xiaoping Chen ◽  
Zuchao Zhu ◽  
...  

AbstractNumerical simulation is performed for the three-dimensional turbulent flow field in a centrifugal pump by solving the Reynolds-averaged Navier-Stokes equations and the RNG k-epsilon turbulent model. The finite volume method and the SIMPLE algorithm are employed for the solution of the system. All the parameters in the centrifugal pump at different blade angular positions are obtained by simulation. The flow structure is analyzed and the distributions of the energy gradient function


2015 ◽  
Author(s):  
Afzal Husain ◽  
Nasser A. Al-Azri ◽  
Abdus Samad ◽  
Sun-Min Kim ◽  
Kwang-Yong Kim

The current study investigated comparative performance of wall-confined and unconfined multiple micro-jet impingement heat sink models for electronic cooling applications. The pressure-drop and thermal characteristics were determined for steady incompressible and laminar flow by solving three-dimensional Navier–Stokes equations. Several parallel and staggered micro-jet configurations consisting of a maximum of 16 jet impingements were tested. The effectiveness of various micro-jet configurations, i.e., inline 2×2, 3×3 and 4×4 jets, and staggered 5-jet and 13-jet arrays with nozzle diameters 50, 76, and 100 μm, were analyzed at various flow rates for the maximum temperature-rise, pressure-drop and heat transfer coefficient characteristics. Two design parameters, the ratio of jet diameter to height of the channel and jet distribution, were chosen for comparative performance analysis.


2013 ◽  
Vol 135 (10) ◽  
Author(s):  
Ling Zhou ◽  
Weidong Shi ◽  
Wei Li ◽  
Ramesh Agarwal

A multistage deep-well centrifugal pump (DCP) with different impeller rear shroud radius have been investigated both numerically and experimentally under multiconditons, which aims at studying the influence of impeller rear shroud radius to the axial force and pump hydraulic performance. During this study, a two-stage DCP equipped with three different impellers was simulated employing the commercial computational fluid dynamics (CFD) software ANYSY-Fluent to solve the Navier-Stokes equations for three-dimensional steady flow. High-quality structured grids were meshed on the whole computational domain. Test results were acquired by prototype experiments, and then compared with the predicted pump performance and axial force. The static pressure distribution in the pump passage obtained by numerical simulation was analyzed. The results indicated that the appropriate impeller rear shroud radius could improve the pump performance and lower the axial force significantly.


Author(s):  
J.-H. Jeon ◽  
S.-S. Byeon ◽  
Y.-J. Kim

The Francis turbine is a kind of reaction turbines, which means that the potential energy of water converted to rotational kinetic energy. In this study, the flow characteristics have been investigated numerically in a Francis turbine on the 15 MW hydropower generation with various blade profiles (NACA 65 and NACA 16 series) and discharge angles (14°, 15°, 17°, and 18°), using the commercial code, ANSYS CFX. The k-ω SST turbulence model is employed in the Reynolds averaged Navier-Stokes equations. The computing domain includes the spiral casing, guide vanes, and draft tube, which are discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The results showed that the change of blade profiles and discharge angles significantly influenced the performance of the Francis turbine.


Sign in / Sign up

Export Citation Format

Share Document