Computational study of SCRAM Jet combustor with a co-axial strut fuel injector
The geometric configuration of Supersonic Combustion Ramjet (SCRAM) is relatively simple when compared to gas turbine engines as there are no moving parts, but the flow physics associated with it is quite complex. At high speeds of flight the residence time of the atmospheric air in the combustion chamber is very low it is of the order of milliseconds, within this short time the fuel injected in to air must efficiently mix and react to release energy in the combustion chamber. The Combustor length and Weight can be minimized and Thrust produced can be maximized by rapid and effective mixing of fuel and oxidizer. The present study focuses on using coaxial type fuel injectors and studies the characteristics of SCRAM Jet Engines. From the results obtained it is observed that the turbulence kinetic energy of the coaxial jets is improved by the four times at the point of fuel injection when compared with the circular jet injector. As Turbulent kinetic energy is one of the parameter indicating the mixing of the fuel and oxidized (air), it is concluded that by employing the coaxial strut fuel injectors the mixing of fuel and oxidized can be enhanced.
CFD Analysis of a Hydrogen Fueled Mixture in Scramjet Combustor with a Strut Injector by Using Fluent Software
In this study, k-ε model has been used to examine supersonic flow in a model scramjet combustor. The configuration used is similar to the DLR (German Aerospace Center) scramjet model and it is consists of a one-sided divergent channel with a wedge-shaped flameholder at the base of which hydrogen is injected. Here, we investigate supersonic cold flow with hydrogen injection. For the purpose of validation, the k-ε results are compared with experimental data for temperature at the bottom wall. In addition, qualitative comparisons are also made between predicted and measured shadowgraph images. The k-ε computations are capable of predicting cold flow simulations well and good.
Cooperative Collection Development
The author discusses cooperative collection development from an historical perspective and examines some of the projects conceived and implemented during the past forty years. In many cases the projects failed even after years of concentrated effort. However, more important than these failures are new efforts that are being made. The major focus of this article is on both current regional projects and the more broadly based ARL-sponsored North American Collections Inventory Project. The author discusses these efforts and offers some specific judgments regarding the possibility that these projects will lead to a truly successful coordinated collection development project on a national basis.