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Supersonic capable STOVL fighter/attack aircraft can provide capabilities for close support and air superiority which will be highly desirable in the future.

An impingement of axisymmetric supersonic jet on the ground is simulated numerically to evaluate the jet flow configuration on the ground, which inclines from 0 to 45 degrees, with a real gas assumption for two-dimensional simulations and with an ideal gas assumption for three-dimensional simulations. ...An experimental study of the underexpanded axisymmetric supersonic N2 jets impinging on a ground which inclines from 0 to 45 degrees is also discussed.

A numerical simulation of shock wave generation by high-pressure and high-speed spray jet has been conducted to compare to the experimental results obtained by X-ray radiographic technique. Using the space-time conservation element solution element (CESE) method and the stochastic particle techniques to account for fuel injections and droplet collisions, supersonic-spray-induced shock waves are successfully simulated. Similar to the experimental condition, a non-evaporating diesel spray in a chamber filled with inert gas sulfur hexafluoride (SF6) at 1 atm pressure under room temperature (30° C) is simulated. To simulate the needle lift effect in the single-hole diesel injector, various injection-rate profiles were employed. In addition, the effects of discharge coefficients, with Cd ranging from 0.8 to 1.0, were also considered to simulate the shock generation processes in the leading spray front.

The stability analysis of plates and shells in high speed flow deals with the determination of the flutter instability boundary. A linear analysis is made using the basic principles of the theory of aero-elasticity of isotropic bodies, the theories of flexible plates, the stability equations and associated boundary conditions obtained through a linear formulation. Herein, the nonlinear stability of flexible plate immersed in a high speed gas flow is considered. The model takes into account quadratic and cubic aerodynamic nonlinearities as well as cubic geometric nonlinearities. It is shown that the inclusion of quadratic aerodynamic nonlinear components can lead to the appearance of “amplitude-frequency” phenomena in both the pre-critical as well as in the post-critical flow speed regimes. The influence of the free stream flow speed on the “amplitude-frequency” dependence phenomena is also presented.

Supersonic jet / resonance enhanced multi-photon ionization (Jet-REMPI) technique was focused on the analyzing method for gas mixture like exhaust gas from automobiles.

No greater contribution seems to exist for improving supersonic transport economics than by improving the state of the art of jet noise suppressors. ...Exact matching of thrust requirements for supersonic cruise, transonic acceleration, climb, and especially takeoff-climb is complex. The present design becomes an equivalent five-engine configuration, where the extra thrust is required to enable environmental levels of FAR Part 36 to be achieved.

This provided information on the motion of the luminous gas particles in its core, revealing that plasma jets can have two distinct modes, being either totally subsonic or embodying a supersonic efflux manifested by the recorded streaks of Mach discs. At a fixed power pulse of electrical energy discharge in the plenum chamber, the outcome depends on the constriction imposed by an orifice at its outlet. ...Whereas the difference between the two types of jets was quite small, penetration in the subsonic case was found to be definitely larger than in supersonic. The turbulent evolution of the puffs was thereupon explored by ultra-high frequency (200 kHz) schlieren cinematography, using a unique system employing a pulsating ruby laser as the light source and a rotating mirror camera as the recorder.

A flow modeling method has been developed to analyze the flow in the annular base (rear-facing surface) of a circular engine nacelle flying at subsonic speed but with a supersonic exhaust jet. Real values of exhaust gas properties and temperature are included. Potential flows of the air and gas streams are computed for the flow past a separated wake.

In this Rankine cycle system, radio-frequency (RF) electric fields are used to ionize a cool supersonic gas, and the Hall effect is used to generate electrical power. Following an analysis of MGD energy conversion and RF plasma production, preliminary design is made of an-experimental system having a generator power density of 10 megawatts/cu m in which 5% of the output power is used to produce the cool plasma.

Real-time analysis of benzene in automobile exhaust gas was performed using the Jet-REMPI (supersonic jet / resonance enhanced multi-photon ionization) method. Real-time benzene concentration of two diesel trucks and one gasoline vehicle driving in Japanese driving modes were observed under ppm level at 1 s intervals.

High performance inlet diffusers for efficient operation in supersonic and hypersonic Mach number ranges can be designed with existing techniques. Design philosophy, however, is complicated.

However, the design of DI systems for compressible gas is challenging due to supersonic flows and the occurrence of shocks. An outwardly opening poppet-type valve design is widely used for DI-CNG.

Here high pressure and high temperature carrier gas is expanded through a converging-diverging nozzle to generate supersonic gas velocity at nozzle exit. The CS process typically uses Helium as the carrier gas due to its low molecular weight, but Helium gas is quite expensive.

A single, efficient, reliable emergency escape system is needed to provide, at an acceptable total cost, emergency escape capability throughout the entire mission envelope of hypersonic and orbital vehicles. Analysis and limited testing indicate that the Douglas Paracone emergency escape system will meet this requirement. The Paracone is a gas-inflatable structure shaped like a cone with a large spherical nose. When the cone is deployed , the crew is positioned and supported within the cone approximately one third the length of the cone as measured from the leading edge of the spherical nose. The crew is suspended over an air mattress flotation plenum chamber which, in turn, is located over a gas impact attenuator.

The results of computational investigations carried out to clarify the possibilities of hydrogen scramjet thrust uprating in hypersonic flight (Mf>8) by adding to the fuel substances with higher density are presented. Thrust, specific impulse and density impulse are calculated while adding nitrogen, oxygen, water or inert liquated gases. For scramjet boosting in hypersonic flight it is suggested to add oxygen or a heavy inert gas to stoichiometric part of hydrogen instead of excessive part of hydrogen.

Making sense of engines Heavy-duty equipment is known for its ruggedness in harsh environments, but vehicles are not neglecting their sensitive side. The world's fastest digger gets closer JCB's Dieselmax goes 350 mph and teaches engineers much about engine capability, extreme testing, and program management. The whole system, and nothing but the system Properly implemented, an electrohydraulic system can add a great deal of automatic control, advanced performance, advanced diagnostics, and remote monitoring to a mobile application. Regenerative hydraulics The use of multiple hydraulic pumps can satisfy the needs of various circuits in off-highway equipment. The gas is greener Biofuels promise to help reduce petroleum cinsumption and CO2 emissions, but much of the potential depends on production and infrastructure investments. Material returns Effective use of materials information is important to engineers in development of parts and components.