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low Reynolds numbers . − J. Fluid Mech., vol.65, pp.97-112. [9] Coutanceau M. and Bouard R. (1977): Experimental determination of the main features of the viscous flow in the wake of a circular cylinder in uniform translation. Part 1. Steady flow . − J. Fluid Mech., vol.79, pp.231-256. [10] Thom A. (1933): The flow past circular cylinders at low speeds . − Proc. R. Soc. Lond. A, vol.141, pp.651-669. [11] Kawaguti M. (1953): Numerical solution of the Navier-Stokes equations for the flow around a circular cylinder at Reynolds number 40 . − J. Phys. Soc. Jpn, vol.8

method. Many researchers have studied Blasius equation among Arikoglu and Ozkol [ 9 ], Fang et al. [ 10 ] and Fang and Lee [ 11 ] have discussed importance for all boundary layer equations. The Blasius equation describes as non-dimensional velocity distribution in the laminar boundary layer over a semi-infinite flat plate. The present investigation is to analyse MHD flow due to a suction / blowing caused by boundary layer of an incompressible viscous flow. The solution of resulting third order nonlinear boundary value problem with an infinite interval is obtained using

References 1. ANSYS Products, Terms & Conditions. ANSYS, Inc. All Rights Reserved, available on: http://www.ansys.com 2. Wróblewski W., Dykas S., Gepert A., 2009, Steam condensing flow modeling in turbine channels, Int. J. Multiphase Flow; Vol. 35(6), pp. 498-506. 3. Yershov S., Rusanov A., 1996, The Application Package FlowER for the Calculation of 3D Viscous Flows Through Multi-Stage Turbomachinery. Certificate of state registration of copyright No. 77, Ukrainian Agency for Copyright and Related Rights, 19.02.1996. 4. Nashchokin V., Semyonov S., 1980

relaxation of aqueous solutions of the serum proteins a2-macroglobulin, fibrinogen, and albumin. Biophys. J. 57, 389-396. Monkos K. (1996). Viscosity of bovine serum albumin aqueous solutions as a function of temperature and concentration. Int. J. Biol. Macromol. 18, 61-68. Monkos K. (2000). Viscosity analysis of the temperature dependence of the solution conformation of ovalbumin. Biophys. Chem. 85, 7-16. Monkos K. (2007a). Temperature dependence of the activation energy of viscous flow for ovalbumin in aqueous solutions. Curr. Top. Biophys. 30, 29-33. Monkos K. (2007b

A comparison of the activation energy of viscous flow for hen egg-white lysozyme obtained on the basis of different models of viscosity for glass-forming liquids

The paper presents the results of viscosity determinations on aqueous solutions of hen egg-white lysozyme at a wide range of concentrations and at temperatures ranging from 5°C to 55°C. On the basis of these measurements and different models of viscosity for glass-forming liquids, the activation energy of viscous flow for solutions and the studied protein, at different temperatures, was calculated. The analysis of the results obtained shows that the activation energy monotonically decreases with increasing temperature both for solutions and the studied protein. The numerical values of the activation energy for lysozyme, calculated on the basis of discussed models, are very similar in the range of temperatures from 5°C to 35°C.

References Aristov S.N. and Gitman I.M. (2002): Viscous flow between two moving parallel disks: exact solutions and stability analysis. - J . Fluid Mechanics, vol.464, pp.209-215. Chandrasekhar S. (1997): Hydrodynamic and Hydromagnetic Stability . - Dover. Craik A. (1989): The stability of unbounded two-and three-dimensional flows subject to body forces: some exact solutions. - J. Fluid Mechanics, vol.198, pp.275-293. Craik A. and Criminale W. (1986): Evolution of wavelike disturbances in shear flows: a class of exact solutions of the Navier

Abstract

In order to quickly obtain practical ship forms with good resistance performance, based on the linear wave-making resistance theory, the optimal design method of ship forms with minimum total resistance is discussed by using the non-linear programming (NLP) method. Taking the total resistance as the objective function (the Michell integral is used to calculate the wave-making resistance and the equivalent plate friction resistance formula is used to calculate the frictional resistance), the hull surface offset as the design variable and appropriate displacement as the basic constraints, and considering the additional constraints, the hull bow shape and the whole ship are optimised, and an improved hull form is obtained. The resistance of the ship before and after optimisation is calculated by the CFD method to further evaluate the resistance reduction effect and performance after optimisation. Finally, an example of optimisation calculation of an actual high-speed ship is given. The obvious resistance reduction results confirm the reliability of the optimisation design method.

References H. Miyata, T. Sato and N. Babo, Difference solution of a viscous flow with free-surface wave about an advancing ship , J. Comput. Phys. , Vol.72, p.393-421, (1987) C. Hochbaum, A finite volume method for turbulent ship flows , Ship Technology Research Schiffstechnik, Hamburg, Germany, (1994) B. Alessandrini and G. Delhommeau, Simulation of three-dimensional unsteady viscous free surface flow around a ship model , Int. J. of Numerical Math. Fluids, Vol.19, p.321-342, (1994) T. Kinoshita, H. Kagemoto and M. Fujino, A CFD application to wave

Abstract

With a liquid displacement flow system, pressure drop and flow measurements were performed on filter rods, tobacco columns and multicapillary pressure drop standards. The purpose of these measurements was to determine the relative contributions of laminar or viscous flow, inertial flow, and entry and exit effects to pressure drop. Pressure drops were obtained both by forcing and drawing air through the article. No difference in pressure drop was obtained by either method provided that the flow was the same at a common point in the rod. This specification was necessary because of the change in flow rate due to gas expansion inside the rod. Pressure drop contributions from gas expansion, thermal effects and rod collapse were negligible. From regression equations, the major pressure drop component in all three types of article was viscous flow, ranging from 98 % of the total pressure drop in filter rods to 79 % in tobacco columns. Entry and exit effects were small in both filter rods and tobacco columns but were appreciable and the only other pressure drop contributor in multicapillaries. These measured entry and exit effects in multicapillaries agreed well with those estimated by flow theory. Inertial flow was found to contribute 1.5 % and 19 % of the total pressure drop in filter and tobacco rods, respectively. These contributions are reasonable from flow theory for packed columns.

Abstract

Inherently porous cigarette paper consists of an interlocking network of cellulose fibres interspersed with chalk particles. Spaces in this matrix are of the order of 1 AAµm wide which is small compared to the paper thickness (usually 20 AAµm to 40 AAµm). However, when cigarette paper is perforated after the paper-making process, e.g. by an electrostatic or mechanical process, the perforation holes are relatively large, usually having mean diameters of the same order of magnitude as the paper thickness. The total flow of air through perforated cigarette paper thus consists of two components: viscous flow through the porous structure of the paper inherent from the paper-making process, and inertial flow through the perforation holes. Since the air flow / pressure relationships due to these two components of flow differ and since the two components are additive, the total flow through perforated paper may be expressed as: Q = Z A P + Z’ A Pn, where Q is the air flow (cm3 min-1), A is the area of paper (cm2) exposed to the flowing air, P is the pressure difference across the paper (kilopascal), Z is the base permeability of the paper due to viscous flow through the spaces inherent from the paper-making process (cm min-1 kPa-1 or Coresta unit), Z’ is the permeability of the paper due to inertial flow through the perforation holes (cm min-1 kPa-1/n) and n is a constant for a given set of perforation holes. This equation adequately describes gas flow through a variety of perforated cigarette and tipping papers. By using different gases, it is confirmed that Z depends on viscous forces and Z’ depends on inertial forces. By examining the flow of air through a large number of papers with perforation holes of different sizes, it is shown that Z’ is dependent on the total area of perforation holes, and that a jet-contraction effect occurs as the air travels through the paper. The parameter n is shown to have a value between 0.5 and 1.0, and this value is related to mean perforation-hole size. The permeability of cigarette paper is defined as the flow of air through the paper when the pressure across the paper is 1 kilopascal. Thus from the above equation the “total permeability” of perforated cigarette paper is equal to Z + Z'.