introduction thunderstorms pose a significant threat to modern societies and their assets. despite their local-scale characteristics, severe thunderstorms and associated extreme events like heavy rainfall, hail, gusts, or tornadoes can cause considerable damage to agriculture, buildings, or infrastructure, and facilities. thunderstorms are highly localized and largely stationary weather systems...

designing and manufacturing the multiple jets simulator and experimental investigation of the multiple jets in crossflow at low velocity ratios have been studied together with design and build a low-speed wind tunnel. a specific rake is used to determine the flow field pressure and changes in static pressure measured by pressure taps in the near field of the jets. there are generally three regi...

An experimental study was performed to investigate the effects of the body angle of attack on the tail surface pressure distribution for a half body-tail combination in subsonic flow. The results show, in small deflection angle regions, that the tail deflection has the same effect on the surface pressure as the body angle of attack. However at moderate to high deflections, the flowfiled caused ...

In the narrow geosynthetic-reinforced retaining walls a stable rear wall exists in a short distance and so there is no enough space to extend appropriate length of reinforcements. In this case, the probability of overturning of retaining wall increases especially when subjected to earthquake loading. To increase the stability of the wall, reinforcements may be connected to the stable rear surfa...

A micromachined sensor array for making optical measurements of surface pressure distributions has been designed, fabricated and tested. Each sensor element in the array consists of a Fabry-Perot etalon fabricated from single-crystal silicon. Illuminating the sensor array with a near-infrared, tunable diode laser and detecting the reflected light intensity with an infrared camera allows remote,...

an experimental study has been performed to investigate the flow physics of an under-expanded axisymmetric supersonic jet exhausting transversely from a flat plate into a subsonic compressible cross flow. the goal was to study the effects of boundary layer thickness ratio (δ/d) and the jet to free stream dynamic pressure ratio (j) on surface pressure. the resulting measurements distinctly show ...

In a polymer membrane fuel cell more than half of the chemical energy of hydrogen is converted to heat during generation of electricity. This causes an increase in the cell temperature. The Cooling field design has a significant role in cell cooling. The cell's performance and stability are reduced due to inappropriate heat dissipation. In this paper, the cooling flow and heat transfer in cooli...

Many metal forming problems have been solved using the slip line field method but all of them have either been two-dimensional (plane strain or plain stress) or axisymmetric problems. In this paper a procedure has been proposed by which the slip line field solution to three dimensional problems of metal forming becomes possible. For this purpose the extrusion of shaped sections has been taken a...