Performance Analysis of Centrifugal Pump Operating as Turbine for Identified Micro/Pico Hydro Site of Ethiopia
| dc.contributor.advisor | Edessa, Dribssa (PhD) | |
| dc.contributor.author | Tsegaye, Bazin | |
| dc.date.accessioned | 2018-07-31T07:36:59Z | |
| dc.date.accessioned | 2023-11-18T06:32:22Z | |
| dc.date.available | 2018-07-31T07:36:59Z | |
| dc.date.available | 2023-11-18T06:32:22Z | |
| dc.date.issued | 2015-06 | |
| dc.description.abstract | In many countries, the supply of electricity in rural areas has always been challenge due to the relative isolation from the national electricity grid. The single most important solution to overcome this problem is through the development of the Micro/Pico hydro power generation. By using a Pump as Turbine (PAT) on particular Micro/Pico hydro sites, the required electricity demand can be more or less fulfilled. This thesis presents performance analysis of PAT for Dabis Hydro site which is located in West Shewa zone. The numerical study of a centrifugal pump running as turbine at different operation conditions was achieved using commercial CFD software Ansys CFX. 3D Navier–Stokes equations were solved using Ansys CFX. The standard k turbulence model was chosen for turbulence model. Using results from simulation, complete characteristic curves of the pump in normal and reverse modes were obtained. After that, the performance of PAT was estimated using various methods proposed by different researchers. The pump mode simulated results was in good agreement with the performance of centrifugal pump evaluated experimentally. The turbine mode performance of the pump was simulated and results showed that when the PAT is made to operate from low to high head condition, the required flow rate at the site increases. And the simulation result of the PAT at best efficiency point (BEP) was compared with results obtained using published empirical formulas and the prediction method proposed by Stephanoff [15] showed acceptable result. In this thesis, the pump was also simulated in reverse modes to evaluate the effect of impeller tip rounding. The result shows that the efficiency of the pump is greatly improved beyond the BEP when the impeller tips is made round. The effects of PAT speed were also studied considering constant flow rate/head conditions and the results indicate that as the impeller speed increase, impeller torque decreases. Whereas as the rotational speed of the PAT increases, the power output as well as the efficiency of the PAT increases till the impeller speed reaches 1400 RPM. Lastly, the effect of draft tube on PAT was simulated and studied. The results show that the PAT head increase when draft tube is added to the system. The result also shows that the system efficiency of the PAT with draft tube drops down due to the increase in head. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/12345678/10610 | |
| dc.language.iso | en | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Thermal Engineering stream | en_US |
| dc.title | Performance Analysis of Centrifugal Pump Operating as Turbine for Identified Micro/Pico Hydro Site of Ethiopia | en_US |
| dc.type | Thesis | en_US |