Sharif Digital Repository

Optimization methodologies with an emphasis on turbomachinery applications are of great interest. In the present study, a framework is proposed for the multi-objective optimization of a compressor blade using a coupled approximator and optimizer modules, as a mean for lowering the vast computational costs. The proposed framework consists of three main units: a CFD solver, an approximator unit, and an optimizer module. In this regard, a multi-layer perceptron artificial neural network is used as the approximator module while a multi-objective genetic algorithm, the non-dominated sorting genetic algorithm-NSGA II, is employed as the optimizer unit of the framework. In addition, a commercial... 

This study considers the flutter analysis rotating blade of a turbo machinery made of magneto rheological elastomer core. The Smith theory is used for modeling the compressible subsonic flow. The classical Hamilton’s principle along with the assume mode method is used to set up the equations of motion. The validity of the derived formulation is confirmed through comparison with those obtained from the finite element software and the available results in the literature. Various parametric studies including the effects of applied magnetic field, core layer thicknesses, rotating speed, setting angle are examined for considered configuration of the rotating blade. The results show that the first... 

In order to investigaton of dynamics behavior and determination of the aeroelastic stability of the turbomachine blade. the turbomachine blade is modeled by using the beam model, taking into account all degrees of freedom, the effect of warping, rotation and seting angle. For aerodynamic modeling, the Smith and Whitehead models are used which are valid in subsonic flow. The validity of the derived formulation is confirmed through comparison with those obtained from the finite element software and the available results in the literature. Then, by using the state feedback controller, the effect of sensor and piezoelectric actuator on the vibrations reduction of the structure and increasing the... 

Recent studies show a great number of micro hydro power potentials all over Iran. They have the capability to generate electricity for shops, residential areas, agricultural communities, and recreational tourism centers. In order to cover the micro hydro power potentials of the country, Sharif University of Technology and Iran Water and Power Resources Development Corporation decided to conduct a project to design and fabricate three types of micro hydropower for the first time in Iran. The potentials with low head and high discharge are located beside rivers and are appropriate places to install axial micro hydro turbine. In this project we tried to prototype an axial micro hydro turbine... 

The ever-increasing need for energy compels researchers to investigate different manners of energy saving. Aَs we know well, one of the effective ways to save energy is to improve the energy consumption of turbomachinery devices such as axial flow fans. Fans are the most applicable of turbomachinery which supply needed airflow, which can be used in ventilation systems, Cooling systems for cars and machines, smoke extraction, and supply required air for firing. Therefore, improving their efficiency can play a significant role in reducing energy consumption and enhancing energy storage. One of the most critical factors in reducing the efficiency of the fans is the stall phenomenon, which can...