Alternative blade materials for technical and ecological optimization of a hydraulic pressure machine

28th IAHR symposium on Hydraulic Machinery and Systems

Schwyzer, Olivier^1 ; Saenger, Nicole^1

Department of Hydraulic Engineering, Faculty of Civil Engineering, Darmstadt University of Applied Sciences, Haardtring 100, Darmstadt

64295, Germany^1

关键词: Continuity properties;    Ecological optimization;    Energy productions;    Hydraulic efficiency;    Hydraulic pressure;    Hydro-power generation;    Laboratory conditions;    Sandwich construction;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/49/10/102015/pdf
DOI  :  10.1088/1755-1315/49/10/102015

来源: IOP

【 摘 要 】

The Hydraulic Pressure Machine (HPM) is an energy converter to exploit head differences between 0.5 and 2.5 m in small streams and irrigation canals. Previous investigations show that efficiencies above 60% are possible. Several case studies indicate good continuity for aquatic life (e.g. fish) and bed load for the technology. The technology is described as an economically and ecologically viable option for small scale hydropower generation. Primary goal of this research is to improve the HPM blade design regarding its continuity properties by maintaining good efficiency rates. This is done by modifying the blade tip and testing within a large physical model under laboratory condition. Blade tips from steel (conventional - reference case) and a combination of EPDM rubber and steel as sandwich construction (rubber, steel, rubber - adhesive layered) are tested and compared. Both materials reach similar values for hydraulic efficiency (approx. 58%) and mechanical power output (approx. 220 W). The variation of different gap sizes pointed out the importance of small clearance gaps to reach high efficiencies. For assessing the two blade tip materials regarding continuity for aquatic life, fish dummies were led through the wheel. Analysis of slow motion video of dummies hit by the blade show significant advantages for the EPDM blade tip. The EPDM rubber allows to bend and thus reduces the shock and the probability for cuts on the fish dummy. It was shown that blade tips from EPDM have certain advantages regarding continuity compared to standard blade tips from steel. No compromise regarding energy production had to be made. These results from the HPM can be transferred to breast shot water wheel and may be applied for new and retrofitting projects.