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Lee, B.H.K. (author), Desrochers, J. (author)Nonlinear flutter of a twodimensional airfoil undergoing plunging and pitching motions is studied using a time marching finite difference scheme. The structural nonlinearity considered is of the type due to a spring with preload and freeplay. Flutter is determined from solutions of the structural dynamic equations of motion when either...report 1987
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Lee, B.H.K. (author), LeBlanc, P. (author)Flutter analysis of a twodimensional airfoil with a cubic nonlinear restoring force in the pitch degree of freedom is investigated. The structural dynamic equations of motion are integrated by a time marching finite difference scheme. Flutter is determined from conditions which give rise to either a divergent or limitamplitude solution. Case...report 1986
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 Lee, B.H.K. (author), LeBlanc, P. (author) report 1986
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Jones, D.J. (author), Lee, B.H.K. (author)As part of the study of the nonlinear response of structural components we investigate in this report a single degreeoffreedom nonlinear response equation usually known as Duffing's equation. Previously the response curves have been investigated analytically by many authors but there seems to have been very little numerical work done in the...report 1985
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 Lee, B.H.K. (author) report 1984
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Lee, B.H.K. (author), Ohman, L.H. (author)Buffet characteristics of the BGK No. 1 shockless airfoil have been investigated. Fluctuating pressure measurements along the airfoil chord and unsteady force balance data have been obtained in various regions inside the buffet rĂ©gime close to the onset boundary curve. The Mach number range where buffet intensity reaches high values is...report 1983
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Lee, B.H.K. (author)A method for the prediction of the response of an elastic wing to random loads at flight conditions using rigid model wind tunnel pressure fluctuation measurements is presented. The wing is divided into panels or elements, and the load is computed from measured pressure fluctuations at the centre of each panel. A series representation with terms...report 1983
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Lee, B.H.K. (author)A method for the prediction of the response of a wing to nonstationary buffet loads is presented. The time history of the applied load is segmented into a number of time intervals. In each time segment, the nonstationary load is represented by the product of a deterministic shaping function and a statistically stationary random function. An...report 1980
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Lee, B.H.K. (author)A method for predicting the response of a wing to nonstationary buffet loads is presented. The wing is treated as a cantilever beam with known mass distribution. Using generalized coordinates, the vibration of the wing is governed by the second order massspringdamper oscillator equation. The buffet load on the wing is expressed as an...report 1979
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Lee, B.H.K. (author), Ribner, H.S. (author)The propagation of a weak normal shock wave through a turbulent atmosphere is studied in terms of an idealized model. The turbulent field is assumed to be weak and represented by the superposition of two inclined shear waves of opposite inclination to the mean flow. The resulting flow is of a cellular nature. The cells are rectangular in shape...report 1972
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Lee, B.H.K. (author), Westley, R. (author)Using experimental measurements of the sound pressure and phase in the near field of a choked screech jet, a method is proposed for computing the effective source positions, their strengths and phases. Two models are considered. The first assumes a distribution of point sourees along the jet axis and the second assumes ring sources along the jet...report 1971
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Lee, B.H.K. (author)A theoretieal treatment of plane progressive sound waves of finite amplitude in a nondissipative medium produced by a piston whose motion contains many different frequeney components is presented herein. The solution of the seeondorder wave equation is represented in the form of a Fourier series and the eoeffieients are expressed in terms of...report 1971
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Lee, B.H.K. (author)The blast wave equations in an unsteady environment are derived. For wedge and conical nozzles it is shown th at the density has a power law vari ation with distance downstream from the throat when the loeal flow Mach number is large. The unsteady flow field behind the blast wave is solved by a perturbation technique and the sel fsimilar...report 1968