To realize the sound pressure unit directly, the method of sound pressure measurement based on acoustic particle velocity with LDA technique was described. In order to get a simple acoustic field, a travelling wave tube was designed. The sound pressure distribution obtained by microphone along the tube was measured. The result showed the acoustic field inside the tube could be considered as tra...

In the most application of nozzle with gas-liquid two-phase flow, the quality of mixture in exhaust of nozzle is the most important parameter as well as the flow velocity. On the other hand, in some industrial application, such as water injection in forced induction (turbocharged or supercharged) internal combustion engine the spray quality is the main goal of designing. In this case and for im...

New Hα Fabry-Perot interferometer observations of the Virgo cluster spiral galaxy NGC 4522 are presented. A velocity field up to a radius of 60 was obtained. The observed rotation curve is symmetric. It is not perturbed in the inner disk. For radii > 50 it shows a solid body rotation. We compare these data with a numerical model which includes the effects of ram pressure stripping. The model ca...

increase of environmental pollution and restricted emission legislations have forced companies to produce automobiles with lower air pollutants. in this respect, discharge of blowby gases into the environment has been prohibited and their recirculation into the combustion chamber is proposed as an alternative solution. in addition, using egr technique to control and reduce nitrogen oxides in in...

An inverse design process is applied to determine blade shapes used in vertical axis wind turbines (VAWTs). The method is based on the modified Garabedian-McFadden technique that uses the deviation of the pressure distribution or the velocity distribution on the surface from a target pressure or velocity distribution, and modifies the blade surface in order to reduce this deviation. The method ...

In order to study effect of complementary pulp distribution, computational fluid dynamic (CFD) was used to research flow characteristic of hydraulic headbox based on complementary pulp distribution. Mass flow rate out of mixing chamber and velocity distribution at slice of headbox were experimented. The results showed that because of simplified design, there were a little gradient of velocity a...