Calculation of Laminar Separation with Free Interaction by the Method of Integral Relations

Calculation of Laminar Separation with Free Interaction by the Method of Integral Relations

Author: Jack Norman Nielsen

Publisher:

Published: 1966

Total Pages: 92

ISBN-13:

DOWNLOAD EBOOK

"A calculative method is presented for determining separated, laminar, boundary-layer characteristics from in front of the separation point to the reattachment point under the influence of 'free interaction' between the main flow and the boundary layer. The analysis covers supersonic flow over two-dimensional and axisymmetric configurations with adiabatic or nonadiabatic wall conditions. For nonadiabatic wall conditions, theories based on first-order coupling and second-order coupling between velocity and total temperature profiles were presented. The theory based on first-order coupling was included in a machine calculation program with options for two-dimensional or axisymmetric flow and adiabatic or nonadiabatic wall conditions. Extensive systematic calculations were made to determine the range of possible separated flows over a two-dimensional configuration as a function of separation point location and wall temperatures. Comparison between experiment and theory for separation pressure distributions on two-dimensional or axisymmetric adiabatic configurations shows generally good agreement. Good comparison between experiment and theory is indicated for a moderately-cooled axisymmetric configuration. For a highly-cooled axisymmetric configuration, the prediction of the machine program based on first-order coupling is inadequate, indicating the necessity for a higher-order coupling theory." -- page iii.


Book Synopsis Calculation of Laminar Separation with Free Interaction by the Method of Integral Relations by : Jack Norman Nielsen

Download or read book Calculation of Laminar Separation with Free Interaction by the Method of Integral Relations written by Jack Norman Nielsen and published by . This book was released on 1966 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A calculative method is presented for determining separated, laminar, boundary-layer characteristics from in front of the separation point to the reattachment point under the influence of 'free interaction' between the main flow and the boundary layer. The analysis covers supersonic flow over two-dimensional and axisymmetric configurations with adiabatic or nonadiabatic wall conditions. For nonadiabatic wall conditions, theories based on first-order coupling and second-order coupling between velocity and total temperature profiles were presented. The theory based on first-order coupling was included in a machine calculation program with options for two-dimensional or axisymmetric flow and adiabatic or nonadiabatic wall conditions. Extensive systematic calculations were made to determine the range of possible separated flows over a two-dimensional configuration as a function of separation point location and wall temperatures. Comparison between experiment and theory for separation pressure distributions on two-dimensional or axisymmetric adiabatic configurations shows generally good agreement. Good comparison between experiment and theory is indicated for a moderately-cooled axisymmetric configuration. For a highly-cooled axisymmetric configuration, the prediction of the machine program based on first-order coupling is inadequate, indicating the necessity for a higher-order coupling theory." -- page iii.


A Critical Evaluation of Analytic Methods for Predicting Laminar Boundary-layer, Shock-wave Interaction

A Critical Evaluation of Analytic Methods for Predicting Laminar Boundary-layer, Shock-wave Interaction

Author: John D. Murphy

Publisher:

Published: 1971

Total Pages: 36

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis A Critical Evaluation of Analytic Methods for Predicting Laminar Boundary-layer, Shock-wave Interaction by : John D. Murphy

Download or read book A Critical Evaluation of Analytic Methods for Predicting Laminar Boundary-layer, Shock-wave Interaction written by John D. Murphy and published by . This book was released on 1971 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:


Analytic Methods in Aircraft Aerodynamics

Analytic Methods in Aircraft Aerodynamics

Author:

Publisher:

Published: 1970

Total Pages: 758

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis Analytic Methods in Aircraft Aerodynamics by :

Download or read book Analytic Methods in Aircraft Aerodynamics written by and published by . This book was released on 1970 with total page 758 pages. Available in PDF, EPUB and Kindle. Book excerpt:


NASA Technical Note

NASA Technical Note

Author:

Publisher:

Published: 1974

Total Pages: 892

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis NASA Technical Note by :

Download or read book NASA Technical Note written by and published by . This book was released on 1974 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt:


Compressible Turbulent Boundary Layers

Compressible Turbulent Boundary Layers

Author:

Publisher:

Published: 1969

Total Pages: 580

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis Compressible Turbulent Boundary Layers by :

Download or read book Compressible Turbulent Boundary Layers written by and published by . This book was released on 1969 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt:


Technical Abstract Bulletin

Technical Abstract Bulletin

Author:

Publisher:

Published:

Total Pages: 760

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis Technical Abstract Bulletin by :

Download or read book Technical Abstract Bulletin written by and published by . This book was released on with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt:


Inhibition of Flow Separation at High Speed

Inhibition of Flow Separation at High Speed

Author: Frederick K. Goodwin

Publisher:

Published: 1969

Total Pages: 60

ISBN-13:

DOWNLOAD EBOOK

This is the last part of a four-part series of reports describing an investigation of the inhibition of boundary-layer separation of the free-interaction type at high speeds through the use of surface cooling. The purpose of this report is to extend the other work of the authors to configurations representative of axisymmetric compression spikes. The analysis is developed and a computer program written for a spike which consists of a conical nose on which separation occurs followed by compression surface. No data were found to compare with the theory. A calculation made with the pressure gradient prescribed by the body shape rather than by free interaction is compared with experiment. The comparisons, which were made for skin friction, heat transfer, and pressure distributions, were good. The significant effect of wall cooling in delaying separation for the prescribed pressure gradient case is shown. It is also shown that a free-interaction solution can be joined to a prescribed pressure gradient solution so that the solution will go smoothly through separation to reattachment.


Book Synopsis Inhibition of Flow Separation at High Speed by : Frederick K. Goodwin

Download or read book Inhibition of Flow Separation at High Speed written by Frederick K. Goodwin and published by . This book was released on 1969 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the last part of a four-part series of reports describing an investigation of the inhibition of boundary-layer separation of the free-interaction type at high speeds through the use of surface cooling. The purpose of this report is to extend the other work of the authors to configurations representative of axisymmetric compression spikes. The analysis is developed and a computer program written for a spike which consists of a conical nose on which separation occurs followed by compression surface. No data were found to compare with the theory. A calculation made with the pressure gradient prescribed by the body shape rather than by free interaction is compared with experiment. The comparisons, which were made for skin friction, heat transfer, and pressure distributions, were good. The significant effect of wall cooling in delaying separation for the prescribed pressure gradient case is shown. It is also shown that a free-interaction solution can be joined to a prescribed pressure gradient solution so that the solution will go smoothly through separation to reattachment.


Advances in Heat Transfer

Advances in Heat Transfer

Author:

Publisher: Academic Press

Published: 1970-07-31

Total Pages: 576

ISBN-13: 9780080575605

DOWNLOAD EBOOK

Advances in Heat Transfer


Book Synopsis Advances in Heat Transfer by :

Download or read book Advances in Heat Transfer written by and published by Academic Press. This book was released on 1970-07-31 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Heat Transfer


Inhibition of Flow Separation at High Speed

Inhibition of Flow Separation at High Speed

Author: Larry L. Lynes

Publisher:

Published: 1969

Total Pages: 72

ISBN-13:

DOWNLOAD EBOOK

The method of integral relations was successfully applied to compressible nonadiabatic turbulent boundary layers on a flat plate. The theory is designed to accept any desired eddy-viscosity model. A particular eddy-viscosity model was incorporated into the method, and the equations were programmed for application to a flat plate with no pressure gradient. The variations of the skin-friction coefficient with Reynolds number, Mach number, and temperature ratio were calculated using this program, and the results are in good accord with similar results calculated by the Spalding-Chi method and the Rubesin T' method. An analysis was made to predict to what extent turbulent separation of the free-interaction type can be inhibited by means of surface cooling. It was observed experimentally that free-interaction is applicable to separated turbulent boundary layers up to the separation point or beyond. The free-interaction model used in the analysis is based on adding the boundary-layer displacement thickness to the actual body dimensions in calculating the induced pressures. The critical temperature ratios calculated on this basis are generally greater than adiabatic wall temperature except in the supersonic range up to a Mach number approaching 3, where moderate cooling is required to inhibit separation.


Book Synopsis Inhibition of Flow Separation at High Speed by : Larry L. Lynes

Download or read book Inhibition of Flow Separation at High Speed written by Larry L. Lynes and published by . This book was released on 1969 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: The method of integral relations was successfully applied to compressible nonadiabatic turbulent boundary layers on a flat plate. The theory is designed to accept any desired eddy-viscosity model. A particular eddy-viscosity model was incorporated into the method, and the equations were programmed for application to a flat plate with no pressure gradient. The variations of the skin-friction coefficient with Reynolds number, Mach number, and temperature ratio were calculated using this program, and the results are in good accord with similar results calculated by the Spalding-Chi method and the Rubesin T' method. An analysis was made to predict to what extent turbulent separation of the free-interaction type can be inhibited by means of surface cooling. It was observed experimentally that free-interaction is applicable to separated turbulent boundary layers up to the separation point or beyond. The free-interaction model used in the analysis is based on adding the boundary-layer displacement thickness to the actual body dimensions in calculating the induced pressures. The critical temperature ratios calculated on this basis are generally greater than adiabatic wall temperature except in the supersonic range up to a Mach number approaching 3, where moderate cooling is required to inhibit separation.


Inhibition of Flow Separation at High Speed

Inhibition of Flow Separation at High Speed

Author: Jack Norman Nielsen

Publisher:

Published: 1969

Total Pages: 68

ISBN-13:

DOWNLOAD EBOOK

The report describes the results of a wind-tunnel test program on an ogive-cylinder-flare combination to determine the extent of laminar separation as a function of wall temperature for fixed free-stream Reynolds number per unit length at a free-stream Mach number of 8.0. The objective of the tests was to see if separation could be eliminated entirely by cooling the wall to a sufficiently low value. Pressure and temperature distributions spanning the separation region were made on a quick-insertion model, but the location of the separation point could not be obtained during the tests. Accordingly, a combined experimental-theoretical method was developed for determining the separation point location. Correlation of the separation length with model temperature ratio indicated that the separation distance was small and was rapidly approaching zero at the lowest wall temperature ratio achieved experimentally. The apparent critical wall temperature ratio so indicated by the data was lower than the theoretical ratio. It was not possible to achieve sufficiently low temperatures to see if separation could be entirely eliminated. Possible reasons for the difference between experiment and theory are discussed.


Book Synopsis Inhibition of Flow Separation at High Speed by : Jack Norman Nielsen

Download or read book Inhibition of Flow Separation at High Speed written by Jack Norman Nielsen and published by . This book was released on 1969 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report describes the results of a wind-tunnel test program on an ogive-cylinder-flare combination to determine the extent of laminar separation as a function of wall temperature for fixed free-stream Reynolds number per unit length at a free-stream Mach number of 8.0. The objective of the tests was to see if separation could be eliminated entirely by cooling the wall to a sufficiently low value. Pressure and temperature distributions spanning the separation region were made on a quick-insertion model, but the location of the separation point could not be obtained during the tests. Accordingly, a combined experimental-theoretical method was developed for determining the separation point location. Correlation of the separation length with model temperature ratio indicated that the separation distance was small and was rapidly approaching zero at the lowest wall temperature ratio achieved experimentally. The apparent critical wall temperature ratio so indicated by the data was lower than the theoretical ratio. It was not possible to achieve sufficiently low temperatures to see if separation could be entirely eliminated. Possible reasons for the difference between experiment and theory are discussed.