الفهرس 
Introduction and literature reviewOnly 14 pages are availabe for public view
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Abstract
The Synergy between the industry and Academia revealed the priority of starting a research project having the goal of producing a validated analytical and numerical design tool for pumps impeller and volute casing. This tool can be used by pump manufacturers to improve efficiency of their old designs without the need to experimentation since visualization is more rich, faster and cheaper. Moreover it encourages creativity and hence new designs can be tried out. Pump design process is difficult because of the complexity of the fluid hydraulic behavior within the pump. Many approximations based on experimental and theoretical data were used by the manufactures and researchers to produce the basics of pump design process. The design process consists of the hydraulic design and mechanical design. The hydraulic design deals with the production of the impeller and volute casing which are the most important components of the centrifugal pump. A suitable design of the two components leads to an efficient and smooth operating pump. Based on review of the researcher’s achievements, many design theories were introduced for the impeller and volute casing designs and there is no optimum design criteria suitable for all centrifugal pumps. The above mentioned research project team was therefore established to discuss the various design theories of impeller and volute casing to investigate the differences between the design methods and their limitations. This thesis is mainly concerned with the volute casing design. In this thesis, different design theories for volute casing of centrifugal pump are presented. In order to facilitate the design process, a MATLAB program code for volute casing design processes is developed with GUI to make it user friendly. The code inputs are the pump required operating point (design point) which identified by the pump flowrate, head and rotational speed. The code outputs are the geometrical dimensions of the required centrifugal pump volute casing. The validation process for this code has been carried out for a multinational manufacture pump with specific speed equals to 9.5 as a case study. The different performance curves and geometrical dimensions of this pump are known. After that the case study pump impeller is used along with the designed volutes extracted from the developed design code to compare the difference between the different design methods of the volute casing. The input to the design code is the case study pump best efficiency point as a design point. The output designed volute casing have been modeled with a 3-D CAD program using the known impeller from the case study. In order to investigate the hydraulic behavior of the designed volute within the pump, CAD model is hydraulically simulated using computational fluid dynamic program ANSYS fluent. The CFD simulation plays a great rule in the design process of the centrifugal pumps by developing the optimized design to reduce the required expensive experimental tests. CFD technique has been applied to investigate the effect of different volute design methods on pump performance at design and off-design conditions, parametric study in the volute casing, showing the pressure contours, velocity vectors of fluid flow within the pump, which would be very difficult to visualize experimentally. Volute parameters such as the criteria of the area distribution along the circumferential length of the volute whether it is constant volute velocity or constant angular momentum are simulated to show the effect of each parameter on pump performance. In order to validate the computer simulation, the computational predicted performance curve of the original pump is compared with the manufacture one and a reasonable matching between the predicted and manufacture performance curves is achieved. The results from the simulation process shows that the volute casing affects dramatically the pump performance and efficiency. The volute casing designed according to constant angular momentum proves to have the best hydraulic performance in the specified specific speed. A further parametric study on the criteria of distributing the volute areas in the direction of flow around the impeller shows that the distribution of the volute areas according to the constant volute velocity approach is more suitable for the pump under consideration.