Two stages gas guns are used for various purposes, particularly for mechanical characterization of materials at high rate of deformations. The performance of a two stages gas gun is studied in this work using the theory of the two-stage gas gun proposed by Rajesh, numerical simulation using combined Eulerian/ Lagrangian elements in Autodyna commercial code and experiment using a two stage gas g...

birds, sometimes numbering in millions, can cause serious damage to grain fields. in order to find a method to accordance with environmental issues and effective in controlling these birds, in this research, the effect of sound was studied for keep birds away. the broadcast unit was developed with the following design criteria: 1) three sound levels of hawk, gas gun and sparrow distress, with f...

High-velocity oxygen fuel (HVOF) thermal spraying uses a combustion process to heat the gas flow and coating material. A computational fluid dynamics (CFD) model has been developed to predict gas dynamic behavior in a HVOF thermal spray gun in which premixed oxygen and propane are burnt in a combustion chamber linked to a parallel-sided nozzle. The CFD analysis is applied to investigate axisymm...

We present a new compact electron gun based on the secondary emission through ionic bombardment principle. The driving parameters to develop such a gun are to obtain a quite small electron gun for an in-flight instrument performing Electron Beam Fluorescence measurements (EBF) on board of a reentry vehicle in the upper atmosphere. These measurements are useful to characterize the gas flow aroun...

The cotton seeds of Namangan-77, Sultan, S-8290, and S-8286 varieties were sown on May 5 with N-200, P-150, K-100 mineral fertilizers irrigated at 70-80-70% LFMC. When the 15, 58.4% was yielded in first harvest from compared to above varieties. Compared other varieties, an increase yield found be 1.3-13.5%. S-8290 15 due wind erosion natural disasters. Data 28.0 q/ha are given.

Although the incidence of pneumoconiosis has been decreasing in Japan, welders’ health hazards due to welding fume inhalation are still serious, because effective engineering methods for controlling fumes are technically difficult to implement in many welding shops. In the 6th notification of general prevention of dust hazards issued by the Japanese Ministry of Health, Labor and Welfare (2003–2...

The compact steep spectrum (CSS) and gigahertz peaked spectrum (GPS) sources are widely believed to be young radio sources, with ages 106 yr. If the activity in the nucleus is fuelled by the supply of gas, one might find evidence of this gas by studying the structural and polarisation characteristics of CSS sources and their evolution through this gas. In this paper we discuss some of the possi...

The compressive behavior of open-cell aluminum alloy foam and stainless steel woven textile core materials have been investigated at three different deformation rate regimes. Quasi-static compressive tests were performed using a miniature loading frame, intermediate rates were achieved using a stored energy Kolsky bar, and high strain rate tests were performed using a light gas gun. In agreemen...

Abstract In order to study the effect of different launch tube diameters gas-driven two-stage light gas guns on flow field during process, a model piston movement in pump projectile was established using Fluent. Using dynamic mesh technology and 6DOF model, numerical simulation process gun carried out, effects tubes velocity bore were obtained. The results show that when mass difference between...