The LOX-Hydrogen J-2X Rocket Engine, which is proposed for use as an upper-stage engine for numerous earth-to-orbit and heavy lift launch vehicle architectures, is presently in the design phase and will move shortly to the initial development test phase. Analysis of the design has revealed numerous potential resonance issues with hardware in the turbomachinery turbine-side flow-path. The analys...

A pump as turbine (PAT) is a turbomachine that converts hydraulic energy into electricity. One of the study topics in PAT efficiency due to centrifugal pumps are not designed operate reverse mode. Geometric variations impeller have been studied literature. However, it was possible evidence influence inclination blade leading and trailing edge. Therefore, objective this work analyze numerically ...

The unsteady flow field in a reversible pump-turbine is investigated during the continuous load rejection using a 3D computational fluid dynamic analysis. Numerical calculations are carried out using the detached eddy simulation (DES) turbulence model and a new approach involving automatic mesh motion. In this way, the instability of the flow field is analyzed by continuously changing the guide...

To meet the demand of power grid for flexible regulation, pump turbines have to frequently and fleetly stop, start, transition between different modes, causing many instability problems. solve problems, understanding complex flow pressure pulsation features in working conditions is prerequisite. In this study, patterns, pulsations, cavitation characteristics, runner forces a prototype pump-turb...

With the increasing connection of controllable devices to isolated community microgrid, an economic operation model of isolated community microgrid based on the temperature regulation characteristics of temperature controlling devices composed of wind turbine, micro-gas turbine, energy storage battery and heat pump is proposed. With full consideration of various economic costs, including fuel c...

The use of renewable energies, especially in metropolises has led to a reduction in environmental pollution and greater access to clean, renewable and sustainable energy. This paper evaluates the effectiveness of a national plan adopted by the Tehran city council for reducing air pollutions. This plan is designed to increase the share of renewable energies in residential buildings. This study a...