http://digitalrepository.fccollege.edu.pk/handle/123456789/469 Mathematics Department Wed, 24 Jun 2026 01:37:21 GMT 2026-06-24T01:37:21Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2661 Title: FLOW OF AN OLDROYD-B FLUID OVER AN INFINITE PLATE SUBJECT TO A TIME-DEPENDENT SHEAR STRESS Authors: Shahid, Dr. Nazish; Rana, Mehwish; Imran, M. A. Abstract: The velocity field and the shear stress corresponding to the unsteady flow of an Oldroyd-B fluid due to an infinite flat plate, subject to a time-dependent shear stress, are established in integral form using the Fourier cosine transform. Similar solutions for Maxwell, Second grade and Newtonian fluids are recovered as limiting cases of general solutions. These solutions satisfy both the governing equations and all imposed initial and boundary conditions. Finally, a comparison between the four models as well as the influence of the pertinent parameters on the fluid motion is underlined by graphical illustrations. Description: N/A Sat, 01 Jan 2011 00:00:00 GMT http://digitalrepository.fccollege.edu.pk/handle/123456789/2661 2011-01-01T00:00:00Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2660 Title: AXIAL-COUETTE FLOW OF AN OLDROYD-B FLUID IN AN ANNULUS DUE TO A TIME-DEPENDENT SHEAR STRESS Authors: Fetecau, Corina; Awan, A. U.; Shahid, Dr. Nazish Abstract: The velocity and the shear stress, corresponding to the unsteady flow of an Oldroyd-B fluid between two infinite circular cylinders, are established using the finite Hankel transform. The motion is produced by the inner cylinder, which after time is pulled with a time-dependent shear stress along its axis. The solutions for Maxwell, Second grade and Newtonian fluids, performing the same motion, are obtained as limiting cases of general solutions. Finally, the influence of the material parameters on the fluid motion is underlined by graphical illustrations. Description: N/A Fri, 01 Jan 2010 00:00:00 GMT http://digitalrepository.fccollege.edu.pk/handle/123456789/2660 2010-01-01T00:00:00Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2659 Title: SOME COUETTE FLOWS OF A VISCOUS FLUID DUE TO TANGENTIAL STRESSES Authors: Shahid, Dr. Nazish; Vieru, Dumitru; Sohail, Ahmad Abstract: Couette flows of a viscous fluid produced by the motion of a wall that applies a tangential stress on the fluid are analyzed. Exact expressions for velocity are determined by means of the Laplace transform. Two particular cases, corresponding to constant and sinusoidal tangential stresses on the wall, are studied. Some relevant properties of the velocity and the volume flux are also presented. Description: N/A Mon, 28 Nov 2011 00:00:00 GMT http://digitalrepository.fccollege.edu.pk/handle/123456789/2659 2011-11-28T00:00:00Z http://digitalrepository.fccollege.edu.pk/handle/123456789/2658 Title: Different forms of the Kadanoff–Baym equations in quantum statistical mechanics Authors: Kondratyev, A.S.; Shahid, Dr. Nazish Abstract: A new form of the Kadanoff–Baym equations for a system of interacting particles is offered on the basis of the retarded and advanced quantum Green’s functions. The comparison of the traditional and the offered forms of the equations allows to analyze the question to what extent Landau–Silin kinetic equations for the neutral Fermi-liquid and for the electron liquid of normal metals take into account quickly varying in space and time disturbances. Description: N/A Sat, 01 Jan 2011 00:00:00 GMT http://digitalrepository.fccollege.edu.pk/handle/123456789/2658 2011-01-01T00:00:00Z