This paper presents a theoretical study on the velocity distribution and the friction factor of boundary layer flows with polymer additives starting from the concept of “stress deficit.” A novel method of order of magnitude analysis is developed, which converts the governing equations of boundary layer flow into a solvable ordinary differential equation, thus the total shear stress distribution...

in the present study, vibration of cylindrical laminates with different layers and angles were studied. in order to actuate and polarize in radial direction, a piezoelectric layer was located at outer surface of composite shell. laminates were assumed long enough so that plane strain state analysis in 2d can be used properly. in order to satisfy the boundary conditions, variables in terms of fo...

Many studies evaluating model boundary-layer schemes focus either on near-surface parameters or on short-term observational campaigns. This reflects the observational datasets that are widely available for use in model evaluation. In this paper we show how surface and long-term Doppler lidar observations, combined in a way to match model representation of the boundary layer as closely as possib...

A regional model is used to study the radiative effect of boundary layer clouds over the Southeast Pacific on large-scale atmosphere circulation during August–October in 1999. With the standard settings, the model simulates reasonably well the large-scale circulation over the eastern Pacific, precipitation in the intertropical convergence zone (ITCZ) north of the equator, and marine boundary la...

in this research, shock wave motion, shock/boundary layer interaction, and flow separation in a transonic flow over a naca0012 airfoil were investigated experimentally. thirteen kulite sensors were utilized for measurement of pressure fluctuations over the airfoil. experiments were performed for angles of attack between -4 to 4 degrees and flow mach numbers of m= 0.39 to 0.82. the kulite sensor...

Surface inhomogeneities, including boundaries between different types of vegetations and land use patterns, have important effects on the structure of the atmospheric boundary layer. Changes in the surface roughness, temperature and wetness make the planetary boundary layer (PBL) nonhomogeneous and produce substantial horizontal gradients of boundary layer properties. Significant differences in...

in this paper, the magnetohydrodynamic (mhd) boundary layer flow over a nonlinear porous stretching sheet is investigated by employing the homotopy perturbation transform method (hptm) and the pade´ approximation. the numerical solution of the governing non-linear problem is developed. comparison of the present solution is made with the existing solution and excellent agreement is noted. graphi...