since knowledge on hydrodynamic torque of a butterfly valve is very important for butterfly valve design, its hydrodynamic torque is investigated in this paper. in reality, the investigation of the loss coefficient and torque from some experiments will take a long time and a lot of money. this paper presents a statistical study of the flow past the butterfly valve in a static analysis using com...

analyzing the nonlinear vibration of beams is one of the important issues in structural engineering. according to this, an impressive analytical method which is called modified iteration perturbation method (mipm) is used to obtain the behavior and frequency of a cantilever beam with geometric nonlinear. this new method is combined by the mickens and iteration methods. moreover, this method don...

the main objective in this paper is creating a method for one-dimensional modeling of multi stage axial flow turbine. the calculation used in this technique is based on common thermodynamics and aerodynamics principles in a mean stream line analyses. in this approach, loss models have to be used to determine the entropy increase across each section in the turbine stage. finally, the analysis an...

design models of multi- stage, axial flow compressor are developed for gas turbine engines. axial flow compressor is one of the most important parts of gas turbine units. therefore, its design and performance prediction are very important. one-dimensional modeling is a simple, fast and accurate method for performance prediction of any type of compressors with different geometries. in this appro...

â â â â â â â â â â â  â  abstract â  the foreign exchange market (fx market) accounts for 40% of the total volume of the world’s e-commerce by its own. based on statistics, sometimes up to 90 per cent of the traders lose their total capital in this market just within six months to one year and leave this market. the probability of loss in the fx market can be estimated by probability theory....

in this paper the reflection coefficient of electromagnetic wave incidence on the walls of the buildings and obstacles that occurs in mobile communication path was modified by solving the riccati nonlinear equations. for this purpose, the building walls are assumed inhomogeneous layers where their permittivity changes as function of the wall thickness. using this reflection coefficient, a new p...