Computational Fluid dynamics based hill chart construction and similarity study of prototype and model francis turbines for experimental tests

Abstract

According to the growing energy demand in Turkey, Hydro Energy Research Laboratory (ETU Hydro) at TOBB University of Economics and Technology was established which is responsible for the Computational Fluid Dynamics (CFD) aided design, manufacturing and standardized performance tests of model hydraulic turbines. The hydroturbine design process at the test center is mainly composed of five steps: preliminary design, CFD aided design, model-prototype similarity analysis, model manufacturing and model tests according to International Electrotechnical Commission (IEC) standards. This study focuses on model-prototype similarity analysis for the turbines to be tested. By using reduced quantities, discharge factor and speed factor, hill chart diagram is obtained for the model using CFD techniques and compared with the hill chart obtained for the prototype. Overall hydraulic characteristics, hydraulic losses, cavitation characteristics are found out for the model. Scale effects on the model turbine are also investigated.