In this paper, a novel PAT system was analyzed and evaluated for utilization at very low specific speeds. Thus, a regenerative pump was employed due to the simplicity, compact size, stable features, low manufacturing costs, and very low specific speed. A theoretical analysis was developed based on the momentum exchange theory to predict the performance characteristics of the regenerative pump in reverse operation. Also, a 3D numerical simulation was implemented to study the performance of the pump in reverse mode. The numerical simulations were validatedwith experimental data of the pump. Results revealed that except for very lowflow rates the presented model provides an acceptable prediction of the PAT performance. Results showed that at BEP, efficiency has decreased by about 20%. The head ratio and discharge ratio was obtained a bout 3.5 and 3.6, respectively. According to the results of entropy generation method, the impeller blades showed themost potential for energy losses. Itwas concluded that regenerative pump could be easily run as a lowspecific speed hydraulic turbine or a pressure reducing valve due to the cheapness, reliability and availability.
