Wyniki wyszukiwania - BazTech

1

Stagnation point flow of Eyring Powell fluid in a vertical cylinder with heat transfer

Rehman A., Achakzai S., Nadeem S., Iqbal S.

Journal of Power Technologies

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2016

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Vol. 96, nr 1

57--62

EN

In this paper an analysis is carried out to examine the effects of natural convection heat transfer for steady boundary layer flow of an Eyring Powell fluid flowing through a vertical circular cylinder. The governing partial differential equations along with the boundary conditions are reduced to dimensionless form by using the boundary layer approximation and applying suitable similarity transformations. The resulting nonlinear coupled system of ordinary differential equations subject to the appropriate boundary conditions is solved using the analytic technique homotopy analysis method (HAM). The effects of the physical parameters on the flow and heat transfer characteristics are presented. The behavior of skinfriction coefficient and Nusselt numbers are also studied for different parameters.

2

Modeling the natural convection heating of liquid in a vertical cylinder

Nowak K., Markowski M., Sztorc E.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2010

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nr 13

10-21

EN

Natural convection heating within a can of liquid food was simulated by solving the governing equations for continuity, momentum and energy conservation in an axisymmetric case using a commercial COMSOL Multiphysics software (Comsol). A physical experiment and computer simulations using four different models were studied. The results allowed to suggest a method of defining the properties of the material and the boundary conditions applied and to determine the usefulness of COMSOL Multiphysics package in modeling the natural convection heating of liquid food.

PL

W pracy przeprowadzono ocenę możliwości wykorzystania pakietu Comsol Multiphysics do modelowania konwekcyjnego ogrzewania cieczy w pionowym zbiorniku w kształcie cylindra. Opisano eksperyment fizyczny oraz symulacje komputerowe procesu oparte na czterech odmiennie zdefiniowanych modelach, zrealizowanych za pomocą pakietu Comsol. Otrzymane wyniki pozwoliły na określenie przydatności pakietu Comsol Multiphysics do modelowania zjawisk konwekcji naturalnej oraz definiowania właściwości modelowanej substancji oraz zastosowanych warunków brzegowych.

3

Thermophoresis free convection from a vertical cylinder embedded in a porous medium

Chamkha A. J., Jaradat M., Pop I.

International Journal of Applied Mechanics and Engineering

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2004

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Vol. 9, no 3

471-481

EN

This paper deals with the steady free convection over an isothermal vertical circular cylinder embedded in a fluid-saturated porous medium in the presence of the thermophoresis particle deposition effect. The governing partial differential equations are transformed into a set of non-similar equations, which are solved numerically using an implicit finite-difference method. Comparisons with the previously published work are performed and the results are found to be in excellent agreement. Many results are obtained and a representative set of these results is displayed graphically to illustrate the influence of the various physical parameters on the wall thermophoretic deposition velocity and concentration profiles.

4

Free convection from a vertical cylinder embedded in a porous medium filled with cold water

Chamkha A. J., Bercea C., Pop I.

International Journal of Applied Mechanics and Engineering

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2004

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Vol. 9, no 2

273-283

EN

A free convection boundary layer flow along a heated vertical cylinder embedded in a porous medium saturated with pure or saline water at low temperatures, up to 20oC, is considered. The boundary layer analysis is formulated in terms of Darcy's law and a new density equation of state, which is of very high accuracy and of simple form, is postulated. Numerical solutions are presented and the flow field characteristics are analysed in detail for both cases of downward and upward flows. A very good agreement between the present results and those reported for particular situations was found.