At lower velocities, the velocity is a function of the volume flow rate at actual conditions which has a term that is the difference of the square of the upstream pressure minus the square of the downstream pressure.Density is a function of both temperature and pressure, so at a constant temperature, mass flow rate is a linear function of pressure. Above about Mach 0.6, velocity is a function of temperature, without a pressure component.Volume flow rate is a function of area and velocity (assuming the discharge coefficient is constant): Mathematically, mass flow rate is volume flow rate times density. For compressible flow an increase in cross sectional area causes the shock wave to expand and allow an increase in velocity at a constant pressure.For incompressible flow (i.e., velocity below about 0.6 M), an increase in cross sectional area causes a decrease in velocity at an increasing pressure.This effect is vividly evident in a diverging nozzle: In subsonic flow, the downstream effects are able to communicate back to the source and downstream effects do change mass flow rate. Canonsburg, Pennsylvania, USAĪnderson JD (1995) Computational fluid dynamics: the basics with applications.In choked flow and in supersonic flow the standing shock wave prevents downstream equipment from communicating back to the source (e.g., friction in downstream pipe is not a factor in the mass flow rate). Int J Eng Res Technol (IJERT) 7(3):366–373Īnsys Help Manual (2021) Ansys, Inc. Tharkude TS, Li DZ (2018) Simulation study of supersonic natural laminar flow on wing with biconvex airfoil. Manshadi MD, Aghajanian S (2018) Computational aerodynamic optimization of wing-design concept at supersonic conditions by means of the response surface method. Keith T, Cioc S, Jiang H (2019) Spreadsheet computations of a symmetric double wedge airfoil in supersonic flow. San Diego, USAĪskari S, Shojaeefard M, Goudarzi K (2011) Numerical and analytical solution of compressible flow over double wedge and biconvex airfoils. Hari N, Schetz JA, Kapania RK (2019) Numerical prediction of interference drag of a strut-surface intersection in supersonic flow. Hodson JD, Christopherson AP, Deaton JD, Pankoninen AM, Reich GW, Beran PS (2019) Aeroelastic topology optimization of a morphing airfoil in supersonic flow using evolutionary design methods. In: Proceedings of 9th international conference on computational fluid dynamics (ICCFD9), Istanbul, Turkey AIP Publishing, Turkey, pp 020002–1–020002–4Īkgun O, Golcuk AI, Kurtulus DF, Kaynak Ü (2016) Drag analysis of a supersonic fighter aircraf. In: AIP conference proceedings, vol 1935, no 1. Sogukpinar H (2018) Estimation of supersonic fighter jet airfoil data and low speed aerodynamic analysis of airfoil section at the Mach number 0.15. It is expected that wing changing geometry will be used not only for military but also for civil supersonic aircraft. Changing wing geometry could lead to less fuel consumption and less noise creation above urban places with airports inside the city area. This paper also promotes the wing morphing technologies due to increases in aerodynamical characteristics when the geometry changes. Also, for supersonic flight regime, the supersonic airfoil configuration provides over 10% higher value for C L/ C D ratio at 1° angle of attack based on the CFD results. It is shown how the maximum ratio of C L/ C D for subsonic configuration is 6.9, whereas for supersonic configuration under equal conditions, the max value for C L/ C D is 7.1, which is around 2.75% increase. The paper shows how a simple simulation-based analysis predicts better aerodynamical characteristics for a wing with changing geometry. The results are obtained with Reynolds averaged Navier–Stokes (RANS), and for resolving of the flow turbulence, the k- ω SST turbulence model was selected. The simulations were done using the Ansys Fluent 2021R Academic Version. Aerodynamic characteristics of the NACA 64A-204 airfoil are evaluated by numerical analysis of the turbulent flow at compressible and high Mach number using computational fluid dynamics (CFD).
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