High-speed flow research has been sponsored and performed at differing levels of effort since the late 1800s. For example, hypersonic research has experienced numerous cycles since the 1950s, with various periods of high research activity, followed by equally long periods of very low activity. Therefore, a chronically weak area in research papers, reports, and reviews is the complete identification of critical background documents that form the building blocks and intellectual heritage for modern compressible flow research. A method for systematically determining these critical references is presented in the context of its application to high-speed flow using Citation-Modern compressible flow solutions pdf Background, which is based on the assumption that many critical documents tend to be highly cited within the literature, although not necessarily recently.
While Citation-Assisted Background is a highly systematic approach for identifying critical references, it is not a substitute for the judgement of the researchers, but rather complements their expertise. In this critical review of high-speed compressible flow, important documents have been identified using Citation-Assisted Background, but other documents have been added by the authors to enhance the picture provided by the highly-cited documents. Check if you have access through your login credentials or your institution. The views in this paper are solely those of the authors, and do not represent the views of the United States Air Force Academy or the Georgia Institute of Technology. Research Affiliate, School of Public Policy.
Professor of Aeronautics, Department of Aeronautics. Screen reader users, click the load entire article button to bypass dynamically loaded article content. Please note that Internet Explorer version 8. Click the View full text link to bypass dynamically loaded article content. In general, the equations of motion are nonlinear in form and not amenable to analytical solution. Special approximate approaches exist for pure subsonic or supersonic flows.
For example, the assumption of small perturbations to the free-stream flow can be exploited to obtain approximate analytical solutions for both subsonic and supersonic flows around wings. Other approximate methods are also explored. Linearized compressible flow theory is used to explore the practical benefits of wing speed for high speed flight. The flight speed called the critical Mach number and methods of estimating it are found based on the results of subsonic small linearized flow. Compressible flow around wings of finite span is discussed. Wave drag, an important aerodynamic phenomenon unique to supersonic flight, is discussed and studied in examples of thin airfoils in compressible flows. The chapter discusses the subsonic linearized compressible flow theory for extending the trusted results from incompressible flow into high subsonic flight.
The most sweeping approximations, producing the simplest solutions, are made here and result in soluble linear differential equations. This leads to the expression linearized theory associated with airfoils. The chapter summarizes the supersonic linearized theory such as symmetrical double wedge airfoil in supersonic flow, supersonic biconvex circular arc airfoil in supersonic flow, general airfoil section, airfoil section made up of unequal circular arcs, double-wedge airfoil section. Several other aspects of supersonic wings such as the shock-expansion approximation, wings of finite span, computational methods are also presented in this chapter. The compressible-flow equations in various forms are considered in order to predict the behavior of airfoil sections in high sub- and supersonic flows. The wings in compressible flow, such as transonic flow, subcritical flow, supersonic linearized theory, and other aspects of supersonic wings are discussed in this chapter.
The analysis of this regime involves solving a set of nonlinear differential equations, a task that demands either advanced computational techniques or some form of approximation. The approximations come about mainly from assuming that all disturbances are small disturbances or small perturbations to the free-stream flow conditions. The chapter also explores the phenomenon of wave drag in supersonic flight and how it is predicted by both the shock-expansion method and linearized supersonic flow. Develop subsonic linearized compressible flow theory for extending the trusted results from incompressible flow into high subsonic flight. See how the different fluid physics for supersonic flow lead to a linearized solution different from that for subsonic compressible flow, and realize the remarkable simplicity of the linearized pressure coefficient for supersonic small-perturbation theory.
Begin to explore the phenomenon of wave drag in supersonic flight and how it is predicted by both the shock-expansion method and linearized supersonic flow. This article has not been cited. If we take a cyclindrical container, fill any liquid upto certain level and then put a piston such that it touches the surface of water. If we start compressing the liquid, will the liquid compress? Assuming the walls to be perfectly rigidthis questoin arised from the topic ,”are liquids compressible”? Liquids are compressible, otherwise shock and sound waves would not exist! The terminus incompressible is not a physical state.