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On the problem of determining the separation point of the laminar boundary layer by the example of the Howart–Tani flow

https://doi.org/10.29235/1561-8323-2024-68-1-79-88

Abstract

A new approach is proposed how to calculate the laminar boundary layer in slow flows. It is based on describing the velocity profile using a polynomial of indefinite degree and on introducing two additional coordinate-dependent parameters, one of which defines the separation of the boundary layer from a wall once this parameter reaches zero. The approach based on three integral relations and reducing the problem to the system of three ordinary differential equations was further developed. A numerical analysis performed for the Howart–Tani flow showed that the separation point of a laminar boundary layer is determined highly exactly using this approach. It was shown that introducing into consideration certain restrictions for the outer surface of a boundary layer allows one to find the problem solutions which would adequately define and fairly exactly determine the flow velocity distribution within this layer, and at any point up to the point of its separation. The proposed numerical-analytical calculation method based on three integral relations and two additional parameters and involving the definition of the flow velocity profile by a polynomial of indefinite degree can be extended to other slow flows past smooth two-dimensional surfaces.

About the Author

V. A. Kot
A.V. Luikov Heat and Mass Transfer Institute of the National Academy of Sciences of Belarus
Belarus

Kot Valery A. – Ph. D. (Engineering), Senior Researcher.

15, P. Brovka Str., 220072, Minsk



References

1. Wendt J. F. Computational Fluid Dynamics. An Introduction. Berlin, 2009. https://doi.org/10.1007/978-3-540-85056-4

2. Schlichting H., Gersten K. Boundary layer theory. Berlin, 2000. https://doi.org/10.1007/978-3-642-85829-1

3. Hartree D. R. A Solution of the Laminar Boundary-Layer Equation for Retarded Flow. British Aeronautical Research Council, 1939.

4. Howart L. On the solution of the laminar boundary layer equations. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 1938, vol. 164, no. 919, pp. 547–579. https://doi.org/10.1098/rspa.1938.0037

5. Goldstein S. On laminar boundary-layer flow near a position of separation. The Quarterly Journal of Mechanics and Applied Mathematics, 1948, vol. 1, no. 1, pp. 43–69. https://doi.org/10.1093/qjmam/1.1.43

6. Stewartson K. Is the Singularity at Separation Removable? Journal of Fluid Mechanics, 1970, vol. 44, no. 2, pp. 347. https://doi.org/10.1017/s0022112070001866

7. Wehrle V. A. Determination of the Separation Point in Laminar Boundary-Layer Flows. AIAA Journal, 1986, vol. 24, no. 10, pp. 1636–1641. https://doi.org/10.2514/3.9494

8. Dumitrescu H., Cardo V., Alexandrescu N. Computation of Separating Laminar Boundary-layer Flows. Proceedings of the Romainan Academy, Seria A., 2003, vol. 3, no. 3, рр. 151–156.

9. Bayeux C., Radenac E., Villedieu P. Theory and Validation of a 2D Finite-Volume Integral Boundary Layer Method for Icing Applications. AIAA Journal, 2019, vol. 57, no. 10. https://doi.org/10.2514/1.j057461

10. Sunmonu A. Development and Separation of Forced Convective Flow. Nonlinear Analysis and Differential Equations, 2016, vol. 4, no. 16, pp. 751–778. https://doi.org/10.12988/nade.2016.6869

11. Akinrelere E. A. Forced convection near Laminar Separation. Aeronautical Quarterly, 1981, vol. 32, no. 3, pp. 212–227. https://doi.org/10.1017/s000192590000915x

12. Tani I. On the solution of the laminar boundary layer equations. Journal of the Physical Society of Japan, 1949, vol. 4, no. 3, pp. 149–154. https://doi.org/10.1143/jpsj.4.149

13. Kot V. A. New aspects in the theory of laminar boundary layer. Materialy XVI Minskogo mezhdunarodnogo foruma po teplomassoobmenu [Materials of the XVI Minsk International Forum on Heat and Mass Transfer]. Minsk, 2022, pp. 140–145 (in Russian).

14. Giles M. B., Drela M. Two-dimensional transonic aerodynamics design method. American Institute of Aeronautics and Astronautics Journal, 1987, vol. 25, no. 9, pp. 1199–1206. https://doi.org/10.2514/3.9768


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ISSN 1561-8323 (Print)
ISSN 2524-2431 (Online)