Receptivity of a supersonic boundary layer over a flat plate . Part 1 . Wave structures and interactions
نویسنده
چکیده
This paper is the first part of a two-part study on the mechanisms of the receptivity to disturbances of a Mach 4.5 flow over a flat plate by using both direct numerical simulations (DNS) and linear stability theory (LST). The main objective of the current paper is to study the linear stability characteristics of the boundary-layer wave modes and their mutual resonant interactions. The numerical solutions of both steady base flow and unsteady flow induced by forcing disturbances are obtained by using a fifth-order shock-fitting method. Meanwhile, the LST results are used to study the supersonic boundary-layer stability characteristics relevant to the receptivity study. It is found that, in addition to the conventional first and second modes, there exist a family of stable wave modes in the supersonic boundary layer. These modes play a very important role in the receptivity process of excitation of the unstable Mack modes, especially the second mode. These stable modes are termed mode I, mode II, etc., in this paper. Though mode I and mode II waves are linearly stable, they can have resonant (synchronization) interactions with both acoustic waves and the Mack-mode waves. Therefore, the stable wave modes such as mode I and mode II are critical in transferring wave energy between the acoustic waves and the unstable second mode. The effects of frequencies and wall boundary conditions for the temperature perturbations on the boundary-layer stability and receptivity are also studied.
منابع مشابه
Receptivity of a supersonic boundary layer over a flat plate . Part 2 . Receptivity to free - stream sound
In this paper, we continue to study the mechanisms of the receptivity of the supersonic boundary layer to free-stream disturbances by using both direct numerical simulation and linear stability theory. Specifically, the receptivity of a Mach 4.5 flow over a flat plate to free-stream fast acoustic waves is studied. The receptivity to free-stream slow acoustic waves, entropy waves and vorticity w...
متن کاملA Novel Similarity Solution of Turbulent Boundary Layer Flow over a Flat Plate
In this paper, the similarity solution of turbulent boundary layer flow on the flat plate with zero pressure gradients is presented. By employing similarity variables the governing partial differential equations are transformed to ordinary ones with inconsistent coefficients and solved numerically with the use of Runge–Kutta and shooting methods in conjunction with trial and error procedure. Fo...
متن کاملAnalytical Solution of The Laminar Boundary Layer Flow over Semi-Infinite Flat Plate: Variable Surface Temperature
In this paper, the problem of forced convection over a horizontal flat plate under condition of variable plate temperature is presented and the homotopy perturbation method (HPM) is employed to compute an approximation to the solution of the system of nonlinear differential equations governing the problem. This paper provides good supplements to the existing literature and generalizes the previ...
متن کاملStudy of Boundary Layer Convective Heat Transfer with Low Pressure Gradient Over a Flat Plate Via He’s Homotopy Perturbation Method
متن کامل
Approximate solution of laminar thermal boundary layer over a thin plate heated from below by convection
In this paper, an integration of a symbolic power series method - Padé approximation technique (PS - Padé), was utilized to solve a system of nonlinear differential equations arising from the similarity solution of laminar thermal boundary layer over a flat plate subjected to a convective surface boundary condition. As both boundary conditions tended to infinity, the combination of series solut...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003