Editor’s Note: This is the fourth in a series of profiles provided by the Hydro Research Foundation that highlight potential future members of the hydroelectric power industry and their accomplishments.
The Hydro Research Foundation is actively supporting graduate students to conduct research related to conventional and pumped storage hydropower. These students are funded through the Department of Energy’s Water Power Program and industry partners through a five year US$3.7 million dollar grant.
Keith Martin will graduate this month from The Pennsylvania State University with a Masters degree in mechanical engineering. Martin grew up near Lancaster, Pa. He completed his undergraduate study at The Pennsylvania State University. In the summer of 2010, he participated in a hydropower research group where he learned to apply computational fluid dynamics (CFD) to turbomachines. Martin believes that hydropower is exciting field that is poised for growth and wants to contribute to the field through research on pump-turbines that can be found in pumped storage facilities.
Keith’s research focused on the Analysis of the Effects of Pre-Swirl on the Efficiency and Operating Range of Hydro Pumps used in pumped-storage. Pumps traditionally operate at a constant speed at their peak efficiency point. Even though variable speed motors allow operators to vary pump capacity, changing pump speeds shifts the operating point away from optimum efficiency. One possible method of expanding the efficient operating rage is to adjust the amount of prewhirl at the inlet of pumps.
The research focuses on the effects of pre-swirl on the operating range of pumps used in pumped-storage hydropower and renewable energy storage facilities. The goal of the research is to show that adjustable prewhirl can be used to expand the practical operating ranges of variable speed pump-turbines in pump mode without adversely affecting efficiency in generating mode.
In turbines, wicket gates are used at the inlet to redirect flow and increase efficiency. In a similar manner, prewhirl in pumps can be achieved by adding directional vanes at the inlet of pumps to cause water to swirl as it enters the pump. Computational fluid dynamic (CFD) software has been used to predict operating conditions of a model pump at various inlet flow conditions.
A case study will be conducted to determine the effects of pre-swirl on the efficiency and operating range of turbomachines in pumped storage facilities. Keith is spending the upcoming year working on micro hydro solutions in Zambia for an international non-governmental organization before seeking a full-time position late 2015.