Experimental study of the impact of N-wave on heat transfer in a boundary layer of a flat plate at the Mach number 2

A hypersonic gun tunnel has been used to measure the heat transfer to a sharpedged flat plate inclined at various incidences to generate local Mach numbers from 3 to 9. The measurements have been compared with a number of theoretical estimates by plotting the Stanton number against the energy-thickness Reynolds number. The prediction giving the most reasonable agreement throughout the above Mach number range is that due to Fernholz (1971).The values of the skin-friction coefficient derived from velocity profiles and Preston tube data are also given.

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Investigation of Flat-Plate Hypersonic, Turbulent Boundary Layers With Heat Transfer

Journal of Applied Mechanics ◽

10.1115/1.3641706 ◽

1961 ◽

Vol 28 (3) ◽

pp. 323-329 ◽

Cited By ~ 6

Author(s):

Eva M. Winkler

Keyword(s):

Heat Transfer ◽

Boundary Layer ◽

Friction Coefficient ◽

Mach Number ◽

Flat Plate ◽

Skin Friction ◽

Boundary Layers ◽

Skin Friction Coefficient ◽

Turbulent Boundary Layers ◽

Reynolds Analogy

Naturally turbulent boundary layers on a cooled flat plate have been investigated at several distances from the leading edge of the plate at a Mach number of 5.2 for three rates of steady-state heat transfer to the surface. Measurements of Pitot and static pressures and of total and wall temperatures made it possible to compute velocity profiles, static-temperature profiles, and boundary-layer parameters without resorting to assumptions. The data demonstrate that the Reynolds analogy between skin friction and heat transfer is valid for all conditions of the present experiments. With increasing rate of heat transfer to the surface, the skin-friction coefficient was found to decrease, a phenomenon opposite to that predicted by theories and empirical relations. On the basis of the present data and other published results of compressible and incompressible turbulent boundary-layer skin friction, a simple relation was devised which describes closely the variation of the skin-friction coefficient with Mach number, heat-transfer rate, and momentum-thickness Reynolds number.

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About the Relationship between Disturbances in a Free Supersonic Flow and Disturbances in a Boundary Layer at Mach Number 2

Siberian Journal of Physics ◽

10.25205/2541-9447-2020-15-2-50-60 ◽

2020 ◽

Vol 15 (2) ◽

pp. 50-60

Author(s):

Afanasev ◽

Kosinov ◽

Yermolaev ◽

Semionov

Keyword(s):

Boundary Layer ◽

Experimental Study ◽

Mach Number ◽

Supersonic Flow ◽

Flat Plate ◽

Cross Sections ◽

Measurement System ◽

Hot Wire ◽

Turbulent Transition ◽

The Relationship

An experimental study of the effect of pulsations of free supersonic flow on the pulsations of the boundary layer of a flat plate with a sharp edge using a new three-channel hot-wire anemometer measurement system is carried out. The spatial-temporal distributions of the correlation coefficient are obtained for the boundary layer cross sections and for the laminar-turbulent transition region.

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An appraisal of ‘flat plate’ closure for the approximate solution of boundary layer problems

The Aeronautical Journal ◽

10.1017/s0001924000021564 ◽

1987 ◽

Vol 91 (908) ◽

pp. 373-389

Author(s):

D. I. A. Poll ◽

C. M. Hellon

Keyword(s):

Heat Transfer ◽

Boundary Layer ◽

Mach Number ◽

Flat Plate ◽

High Speed ◽

Compressible Flows ◽

Incompressible Flows ◽

Similarity Solutions ◽

Laminar Flows ◽

Reynolds Analogy

SummaryThe usefulness of zero pressure gradient, flat plate closure relations in providing approximate solutions for the boundary layer momentum and energy integral equations is examined. Expressions are obtained for skin friction, surface heat transfer rate and local Reynolds analogy factor under general compressible flow conditions. For laminar flows the predictions are compared with well known similarity solutions, with some exact solutions for non-similar flows and with experimental heat transfer data for high speed flow over a blunt cone. Consideration is also given to situations in which the surface temperature is a function of position. For turbulent flow situations comparisons are made with experimental data obtained from two-dimensional and axi-symmetric tests. Conditions vary from low Mach number incompressible flows through to high Mach number compressible flows with highly cooled walls. Some comparisons are also made with other prediction techniques.

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Skin Friction in the Laminar Boundary Layer in Compressible Flow

Aeronautical Quarterly ◽

10.1017/s0001925900000123 ◽

1949 ◽

Vol 1 (2) ◽

pp. 137-164 ◽

Cited By ~ 18

Author(s):

A. D. Young

Keyword(s):

Heat Transfer ◽

Boundary Layer ◽

Mach Number ◽

Flat Plate ◽

Skin Friction ◽

Compressible Flow ◽

Laminar Boundary Layer ◽

Momentum Equation ◽

Forward Movement ◽

Semi Empirical

SummaryFrom an analysis of the work of Crocco and others, semi-empirical formulae are derived for the skin friction on a flat plate at zero incidence with a laminar boundary layer. These formulae arefor the general case of heat transfer, andwhen there is no heat transfer.The problem of heat transfer and the effect of radiation are discussed in the light of these formula;. The second formula is then utilised in the development of an approximate method for solving the momentum equation of the boundary layer on a cylinder without heat transfer. The method indicates that with increase of Mach number there is a marked forward movement of separation from a flat plate in the presence of a constant adverse velocity gradient.

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Experimental study of thermohydraulic characteristics and irreversibility analysis of novel axial corrugated tube with spring tape inserts

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200192 ◽

2020 ◽

Vol 92 (3) ◽

pp. 30901

Author(s):

Suvanjan Bhattacharyya ◽

Debraj Sarkar ◽

Ulavathi Shettar Mahabaleshwar ◽

Manoj K. Soni ◽

M. Mohanraj

Keyword(s):

Heat Transfer ◽

Experimental Study ◽

Thermal Performance ◽

Working Fluid ◽

The Novel ◽

Heat Exchanger Tube ◽

Heat Transfer Augmentation ◽

Corrugated Tube ◽

The Impact ◽

Exchanger Tube

The current study experimentally investigates the heat transfer augmentation on the novel axial corrugated heat exchanger tube in which the spring tape is introduced. Air (Pr = 0.707) is used as a working fluid. In order to augment the thermohydraulic performance, a corrugated tube with inserts is offered. The experimental study is further extended by varying the important parameters like spring ratio (y = 1.5, 2.0, 2.5) and Reynolds number (Re = 10 000–52 000). The angular pitch between the two neighboring corrugations and the angle of the corrugation is kept constant through the experiments at β = 1200 and α = 600 respectively, while two different corrugations heights (h) are analyzed. While increasing the corrugation height and decreasing the spring ratio, the impact of the swirling effect improves the thermal performance of the system. The maximum thermal performance is obtained when the corrugation height is h = 0.2 and spring ratio y = 1.5. Eventually, correlations for predicting friction factor (f) and Nusselt number (Nu) are developed.

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