Download or read book A Numerical Study of Oblique Detonation Wave Combustion written by Brent Steven Green and published by . This book was released on 1995 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Study of Detonation Wave Proagation in Combustion Wave Ignition CWI System written by Jeong-Yeol Choi and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical study of detonation stabilization by finite length ramps written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nesta dissertação apresentam-se os resultados de um estudo numérico da interação entre uma onda de detonação oblíqua forte estabilizada pela rampa de um diedro e o leque expansão gerado pela deflexão da superfície do diedro. Neste estudo foi utilizado um código numérico que resolve asequações que governam o escoamento de uma mistura reativa de hidrogênio e ar. Estas equações são discretizadas por um procedimento do tipo volumes finitos centrado na célula de cálculo, segundo um esquema que leva em contaas velocidades características do escoamento. A presença de ondas de choque e detonação requer o uso de procedimentos de adaptação de malha. Neste trabalho procedimentos de enriquecimento e empobrecimento de malha são usados, o primeiro para melhorar a resolução das regiões do escoamento nas quais ocorrem grandes gradientes das propriedades, enquanto o segundo para retirar pontos da malha em locais onde os gradientes são pequenos. Mostra-se que este procedimento de empobrecimento, desenvolvido neste trabalho, resulta em ganhos no tempo de processamento. Na determinação dos parâmetros que levem a obter ondas do tipo Chapman-Jouguet como resultado da interação, inicialmente é realizada uma análisequase uni-dimensional baseada nos diagramas das polares de detonação e nos diagramas do tempo de indução da mistura reativa. Em seguida, os resultados das simulações numéricas mostram que a obtenção de uma detonação do tipo Chapman-Jouguet é possível para valores intermediáriosdo ângulo diedro, dentro da faixa das detonações estáveis. Quando o ângulo do diedro é próximo ao ângulo máximo permitido para detonações estáveis obteve-se o desacoplamento da onda de detonação, com a subsequente extinção do processo de combustão.

Download or read book NASA Glenn Coefficients for Calculating Thermodynamic Properties of Individual Species written by Bonnie J. McBride and published by . This book was released on 2002 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Study of Shock induced Combustion in Methane air Mixtures written by Shaye Yungster and published by . This book was released on 1993 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Preliminary Simulation for Oblique Detonation Wave Engine written by Yi-Jhen Wu and published by . This book was released on 2022 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study investigates the phenomena of flow dynamics and the system performance of oblique detonation wave engines (ODWEs) using a single-step reactive model. In order to properly treat numerical stiffness due to chemical reactions, the time-operator splitting method is used. The AUSMDV numerical flux combined with the ATM (Average of THINC and MUSCL) scheme is chosen to discretize spatial terms in the governing equations. Also the two-step second-order Runge-Kutta method is used for temporal discretizations. The boundary conditions on the wall and at both the inlet and outlet are presented for the inviscid flow. Numerical benchmark test cases are performed on the problems considering different Mach numbers, temperatures, dilution gases, hypersonic wedge angles, grid resolutions, time steps, a preliminary simulation for three-dimensional effects, and different angle tests of combustor wedges in an ODWE. The numerical simulation shows that the single-step reactive model can simulate most of the physical phenomena as required. Additionally, the single-step reactive model is very efficient to acquire the results in a faster time. Due to the ATM scheme, the oscillatory behavior of the cell-like front structure and three-dimensional effects are shown to clearly capture for the cases of the ODW, especially for developing ODWE, also for the two-dimensional shock-induced combustion or a detonation wave in the combustor.

Download or read book A Numerical Study of Attached Oblique Detonation written by James A. Fort and published by . This book was released on 1993 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Numerical Study of Overdriven Detonation Waves written by Balu Sekar and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hypersonic Airbreathing Propulsion written by William H. Heiser and published by AIAA. This book was released on 1994 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: An almost entirely self-contained engineering textbook primarily for use in undergraduate and graduate courses in airbreathing propulsion. It provides a broad and basic introduction to the elements needed to work in the field as it develops and grows. Homework problems are provided for almost every individual subject. An extensive array of PC-based user-friendly computer programs is provided in order to facilitate repetitious and/or complex calculations. Annotation copyright by Book News, Inc., Portland, OR

Download or read book Numerical Study of Shock induced Combustion in Methane air Mixtures written by Shaye Yungster and published by . This book was released on 1993 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Simulation of Unsteady Normal Detonation Combustion written by Ajjay Omprakas and published by . This book was released on 2019 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research is to simulate normal detonation combustion which is a mode of operation for a Pulsed Detonation Engine (PDE). A supersonic flow with stoichiometric hydrogen-air mixture is made to impinge on a wedge, thus resulting in increasing the temperature and pressure across a shock wave leading to the formation of detonation wave. Different modes of the operations can be simulated by varying the incoming Mach number, pressure, temperature and equivalence ratio. For the case of normal detonation wave mode which is an unsteady process, after the detonation being initiated due to the shock induced by the wedge, the detonation wave propagates upstream in the flow as the combustion chamber Mach number is lower than the C-J Mach number. The concept of detonation wave moving upstream and downstream is controlled by changing the incoming flow field properties. By this method the unsteady normal detonation wave is made to oscillate in the combustion chamber leading to a continuous detonation combustion. The intention of this research is to simulate two cycles of detonation combustion in order to determine the frequency and to obtain the variation of flow properties at the exit plain with respect to time.

Download or read book Simulation of Conical Oblique Detonation Waves in Hypersonic Flow of H 2 air microform written by Felisa Yue Zhang and published by Library and Archives Canada = Bibliothèque et Archives Canada. This book was released on 2005 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oblique Detonation Wave (ODW) is a key component for hypersonic combustion engines. Its understanding is essential for designing combustors but reliable information on combustion process and exact ODW structure are difficult to obtain. Axisymmetric sharp cones can produce the purest two-dimensional ODW. This study simulates conical ODWs with hypersonic inflow of stoichiometric H2-air at Mach 7.36, using axisymmetric multi-species Laminar Navier-Stokes equations with the Jachimowski and Lutz combustion models. Numerical solutions of inviscid flow, at 40°, 35° and 32° cones, show steady-state overdriven ODW ignited by the pressure coupling of a shock wave and deflagration waves. At 30.5° and 30° cones, the ODWs are near the Chapman-Jouguet (CJ) condition and the coupling occurs between the shock wave and an internal post-shock ODW. The predicted CJ condition is between 30° and 29.5°, with constant detonation angle and minimum entropy being 42.3° and 1864 JkgK . The induction distance is the most sensitive parameter.

Download or read book Numerical Investigation of Oblique Detonation Waves for a Shcramjet Combustor microform written by Giovanni Fusina and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 2003 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Combustion in High Speed Flows written by John Buckmaster and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 639 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the Workshop on Com bustion, sponsored by the Institute for Computer Applications in Science and Engineering (ICASE) and the NASA Langley Research Center (LaRC). It was held on October 12-14, 1992, and was the sec ond workshop in the series on the subject. The first was held in 1989, and its proceedings were published by Springer-Verlag under the title "Major Research Topics in Combustion," edited by M. Y. Hussaini, A. Kumar, and R. G. Voigt. The focus of the second workshop was directed towards the development, analysis, and application of basic models in high speed propulsion of particular interest to NASA. The exploration of a dual approach combining asymptotic and numerical methods for the analysis of the models was particularly encouraged. The objectives of this workshop were i) the genesis of models that would capture or reflect the basic pllysical phenomena in SCRAMJETs and/or oblique detonation-wave engines (ODWE), and ii) the stimulation of a greater interaction between NASA exper imental research community and the academic community. The lead paper by D. Bushnell on the status and issues of high speed propulsion relevant to both the SCRAMJET and the ODWE parallels his keynote address which set the stage of the workshop. Following the lead paper were five technical sessions with titles and chairs: Experiments (C. Rogers), Reacting Free Shear Layers (C. E. Grosch), Detonations (A. K. Kapila), Ignition and Struc ture (J. Buckmaster), and Unsteady Behaviour ('1'. L. Jackson).

Download or read book An Experimental Study of Oblique Detonation Waves written by Jean-Christophe Broda and published by . This book was released on 1993 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamics of Detonations and Explosions written by and published by AIAA. This book was released on 1991 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Study of Upstream and Downstream Regions of One Dimensional Detonation Wave in a Dusty Gas Medium written by Shubhadeep Banik and published by . This book was released on 2015 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In detonative combustion very high temperatures are attained by the burned gases. As a result, a large amount of thermal energy is produced during the combustion process. This heat can affect the state of the unburned fuel through radiation of heat from the burned gases. In this study a one-dimensional model was deemed appropriate to gain insight into the fundamental structure of the detonation wave. In this model, the detonation wave divides the fluid stream into an upstream region, consisting of fuel and oxidant, and a downstream region, consisting of burned gases. A set of computer programs, some developed during the present work and others developed by other investigators, were used in combination. These codes, when used in conjunction with an appropriate chemical reaction mechanism, can work for most gaseous fuel/oxidant mixtures. Ethane-air, methane-air, syngas-air and acetylene-oxygen mixtures, seeded with solid carbon particles, were used. Variation in flow properties were obtained for both the unburned and burned regions. The temperature levels observed in the burned region supports the previous statement regarding high thermal energy generation. The flame structure of the detonation wave region was studied. To study the effect of radiative heating in the unburned upstream region, appropriate emissivity and absorptivity models from literature were used. Carbon particles have a significant role in the upstream side, and as the results reveal, they have a relatively higher heat absorbing capacity than the gaseous components. A study of the amount of burned gas considered represented by the path length in evaluating the amount of heat radiated was also done to understand its effect on the upstream side."--Abstract, page iv.