16 Matching Results

Search Results

Advanced search parameters have been applied.

Second-Order Subsonic Airfoil Theory Including Edge Effects

Description: Several recent advances in plane subsonic flow theory are combined into a unified second-order theory for airfoil sections of arbitrary shape. The solution is reached in three steps: the incompressible result is found by integration, it is converted into the corresponding subsonic compressible result by means of the second-order compressibility rule, and it is rendered uniformly valid near stagnation points by further rules. Solutions for a number of airfoils are given and are compared with the results of other theories and of experiment. A straight-forward computing scheme is outlined for calculating the surface velocities and pressures on any airfoil at any angle of attack.
Date: January 1, 1956
Creator: Van Dyke, Milton D.
Partner: UNT Libraries Government Documents Department

The Similarity Rules for Second-Order Subsonic and Supersonic Flow

Description: The similarity rules for linearized compressible flow theory (Gothert's rule and its supersonic counterpart) are extended to second order. It is shown that any second-order subsonic flow can be related to "nearly incompressible" flow past the same body, which can be calculated by the Janzen-Rayleigh method.
Date: January 1, 1958
Creator: Van Dyke, Milton D.
Partner: UNT Libraries Government Documents Department

A Study of Second-Order Supersonic Flow Theory

Description: Second-order solutions of supersonic-flow problems are sought by iteration, using the linearized solution as the first step. For plane and axially symmetric flows, particular solutions of the iteration equation are discovered which reduce the second-order problem to an equivalent linearized problem. Comparison of second-order solutions with exact and numerical results shows great improvement over linearized theory. For full three-dimensional flow, only a partial particular solution is found. The inclined cone is solved, and the possibility of treating more general problems is considered.
Date: January 1, 1952
Creator: Van Dyke, Milton D.
Partner: UNT Libraries Government Documents Department

A Study of Hypersonic Small-Disturbance Theory

Description: A systematic study is made of the approximate inviscid theory of thin bodies moving at such high supersonic speeds that nonlinearity is an essential feature of the equations of flow. The first-order small-disturbance equations are derived for three-dimensional motions involving shock waves, and estimates are obtained for the order of error involved in the approximation. The hypersonic similarity rule of Tsien and Hayes, and Hayes' unsteady analogy appear in the course of the development. It is shown that the hypersonic theory can be interpreted so that it applies also in the range of linearized supersonic flow theory. Several examples are solved according to the small-disturbance theory, and compared with the full solutions when available.
Date: January 1, 1954
Creator: Van Dyke, Milton D.
Partner: UNT Libraries Government Documents Department

Supersonic Flow Past Oscillating Airfoils Including Nonlinear Thickness Effects

Description: A solution to second order in thickness is derived for harmonically oscillating two-dimensional airfoils in supersonic flow. For slow oscillations of an arbitrary profile, the result is found as a series including the third power of frequency. For arbitrary frequencies, the method of solution for any specific profile is indicated, and the explicit solution derived for a single wedge. Nonlinear thickness effects are found generally to reduce the torsional damping, and so enlarge the range of Mach numbers within which torsional instability is possible.
Date: January 1, 1954
Creator: Van Dyke, Milton D.
Partner: UNT Libraries Government Documents Department

Practical Calculation of Second-Order Supersonic Flow Past Nonlifting Bodies of Revolution

Description: Calculation of second-order supersonic flow past bodies of revolution at zero angle of attack is described in detail, and reduced to routine computation. Use of an approximate tangency condition is shown to increase the accuracy for bodies with corners. Tables of basic functions and standard computing forms are presented. The procedure is summarized so that one can apply it without necessarily understanding the details of the theory. A sample calculation is given, and several examples are compared with solutions calculated by the method of characteristics.
Date: July 1, 1952
Creator: Van Dyke, Milton D.
Partner: UNT Libraries Government Documents Department

Investigation of wing characteristics at a Mach number of 1.53 2: swept wings of taper ratio 0.5

Description: Measured values of lift, drag, and pitching moment at M(sub o) = 1.53 are presented for seven wings varying in sweep angle from 60 degrees sweepforward to 60 degrees sweepback. All wings had a cambered, double-wedge section 5-percent thick and a common taper ratio of 0.5. The experimental results are compared with the predictions of the linear theory.
Date: June 28, 1948
Creator: Vincenti, Walter G.; Van Dyke, Milton D. & Matteson, Frederick H.
Partner: UNT Libraries Government Documents Department