A Meshless Local Petrov-Galerkin Method for Fluid Dynamics and Heat Transfer Applications

2005 ◽  
Vol 127 (4) ◽  
pp. 647-655 ◽  
Author(s):  
Ali Arefmanesh ◽  
Mohammad Najafi ◽  
Hooman Abdi

The meshless local Petrov-Galerkin method has been modified to develop a meshless numerical technique to solve computational fluid dynamics and heat transfer problems. The theory behind the proposed technique, hereafter called “the meshless control volume method,” is explained and a number of examples illustrating the implementation of the method is presented. In this study, the technique is applied for one- and two-dimensional transient heat conduction as well as one- and two-dimensional advection-diffusion problems. Compared to other methods, including the exact solution, the results appear to be highly accurate for the considered cases. Being a meshless technique, the control volumes are arbitrarily chosen and possess simple shapes, which, contrary to the existing control volume methods, can overlap. The number of points within each control volume and, therefore, the degree of interpolation, can be different throughout the considered computational domain. Since the control volumes have simple shapes, the integrals can be readily evaluated.

Author(s):  
Ali Arefmanesh ◽  
Mohammad Najafi ◽  
Hooman Abdi

A novel meshless numerical technique to solve computational fluid dynamics-heat transfer problems is introduced. The theory behind the newly proposed technique hereafter named “The Meshless Control Volume Method” is explained and a number of examples illustrating the implementation of the method is presented. In this study, the technique is applied for one and two dimensional transient heat conduction as well as one and two dimensional advection-diffusion problems. Compared to other methods including the exact solution, the results show to be highly accurate for the considered cases. Being a meshless technique, the control volumes are arbitrary chosen, and they posses simple shapes which contrary to the existing control volume methods can overlap. The number of points within each control volume and, therefore the degree of interpolation can be different throughout the considered computational domain. Since the control volumes are of simple shapes, the integrals can be evaluated analytically.


Author(s):  
Cemil Koyunoğlu

Mathematical modeling of the heat pump as a result of continuity, momentum, and energy equations is obtained. To solve these equations numerically, the problem is divided by a finite number of control volumes. Then the differential equations in these control volumes integrated and converted into algebraic equations. The importance of computational fluid dynamics in Industry 4.0 applications is to make current applications more efficient in heat pump applications. In this study, the book section is composed of the application of computational fluid dynamics by the control volume method using Ansys fluent program, which will benefit readers from industry 4.0 perspective, especially in energy efficiency issues according to the volume method of controlling correct heat pump designs.


Author(s):  
Y Yue ◽  
T. A. Stolarski

The objective of this paper is to develop an accurate numerical procedure for the analysis of nominally flat contacts with spiral grooves lubricated by gases. The numerical procedure, which is based on the control-volume method, enables the solutions of the non-linear Reynolds equation to be obtained without limitation in geometry and operating conditions. Satisfactory flow balance was achieved on the control volumes as well as on the whole boundary and the method was proved to be very accurate. Convergence of the method was quick for any compressibility number. Three types of contact with spiral grooves were analysed. They were hydrodynamic bearings without interior chambers, hydrodynamic bearings with interior chambers and hybrid bearings. The effects of spiral angle, groove geometry (length, depth and width) and compressibility on performances were investigated for all possible designs.


2000 ◽  
Author(s):  
M. Greiner ◽  
P. F. Fischer ◽  
H. M. Tufo

Abstract Two-dimensional Navier-Stokes simulations of heat and momentum transport in an intermittently grooved passage are performed using the spectral element technique for the Reynolds number range 600 ≤ Re ≤ 1800. The computational domain has seven contiguous transverse grooves cut symmetrically into opposite walls, followed by a flat section with the same length. Periodic inflow/outflow boundary conditions are employed. The development and decay of unsteady flow is observed in the grooved and flat sections, respectively. The axial variation of the unsteady component of velocity is compared to the local heat transfer, shear stress and pressure gradient. The results suggest that intermittently grooved passages may offer even higher heat transfer for a given pumping power than the levels observed in fully grooved passages.


2016 ◽  
Vol 831 ◽  
pp. 83-91
Author(s):  
Lahoucine Belarche ◽  
Btissam Abourida

The three-dimensional numerical study of natural convection in a cubical enclosure, discretely heated, was carried out in this study. Two heating square sections, similar to the integrated electronic components, are placed on the vertical wall of the enclosure. The imposed heating fluxes vary sinusoidally with time, in phase and in opposition of phase. The temperature of the opposite vertical wall is maintained at a cold uniform temperature and the other walls are adiabatic. The governing equations are solved using Control volume method by SIMPLEC algorithm. The sections dimension ε = D / H and the Rayleigh number Ra were fixed respectively at 0,35 and 106. The average heat transfer and the maximum temperature on the active portions will be examined for a given set of the governing parameters, namely the amplitude of the variable temperatures a and their period τp. The obtained results show significant changes in terms of heat transfer, by proper choice of the heating mode and the governing parameters.


Author(s):  
Dwi Listriana Kusumastuti

Water, oil and gas inside the earth are stored in the pores of the reservoir rock. In the world of petroleum industry, calculation of volume of the oil that can be recovered from the reservoir is something important to do. This calculation involves the calculation of the velocity of fluid flow by utilizing the principles and formulas provided by the Fluid Dynamics. The formula is usually applied to the fluid flow passing through a well defined control volume, for example: cylinder, curved pipe, straight pipes with different diameters at the input and output, and so forth. However, because of reservoir rock, as the fluid flow medium, has a wide variety of possible forms of the control volumes, hence, calculation of the velocity of the fluid flow is becoming difficult as it would involve calculations of fluid flow velocity for each control volume. This difficulties is mainly caused by the fact that these control volumes, that existed in the rock, cannot be well defined. This paper will describe a method for calculating this fluid flow velocity of the control volume, which consists of a combination of laboratory measurements and the use of some theories in the Fluid Dynamics. This method has been proofed can be used for calculating fluid flow velocity as well as oil recovery in reservoir rocks, with fairly good accuration.


2014 ◽  
Vol 354 ◽  
pp. 227-235
Author(s):  
Marcelo J.S. de Lemos

This article presents a thermo-mechanical approach to investigate heat transfer between solid and fluid phases in a model gasifier. A two-temperature equation approach is applied in addition to a macroscopic model for laminar flow through a porous moving bed. Transport equations are discretized using the control-volume method and the system of algebraic equations is relaxed via the SIMPLE algorithm. The effects on inter-phase heat transfer due to variation of medium permeability, thermal conductivity and thermal capacity are analyzed. Results indicate that for smaller medium permeabilities, as well as for higher solid-to-fluid thermal capacity and thermal conductivity ratios, enhancement of heat transfer between phases is observed.


Author(s):  
Longjian Li ◽  
Yihua Zhang ◽  
Wenzhi Cui ◽  
Tien-Chien Jen ◽  
Qinghua Chen ◽  
...  

Micro-nozzle, based on the MEMS technology, has played an important role in orbit positioning, attitude adjusting and other applications of micro-satellites. The continuous no-slip model of two-dimensional compressible laminar flow in the micro-nozzle was proposed and solved numerically by finite control volume method. The flow and heat transfer in the micro-nozzle were computed under different conditions, including different inlet pressures, different inlet temperatures and different divergent angles. Flow field and effects of these conditions on the propulsion performance were analyzed. Finally, simulated solutions were compared and validated with the experimental results.


Author(s):  
Dieter Peitsch ◽  
Heinz E. Gallus ◽  
Stefan Weber

Subject of this paper is a numerical method for the simulation of flutter in three dimensional oscillating cascades. Unsteadiness can be caused by bending and torsional oscillation modes simultaneously. The goal of the investigation is the evaluation of the resulting blade forces and moments. The flow is assumed to be time-dependent and inviscid. By solving the Euler equations in a nonlinear way, large oscillations as well of the airfoil as of existing shocks can be treated. The numerical solution follows a Godunov-type upwind scheme, formulated in node centered finite volume technique. An approximative Riemann solver proposed by Roe is used to determine the fluxes over the surfaces of the control volume. Since unphysical expansion shocks have to be suppressed, a modification of the transonic characteristic speeds is included. The extrapolation of the flow values onto the control volumes’ surfaces is done by means of the MUSCL technique, embedded in a TVD-scheme with the flux limiter by van Albada. The computational domain is restricted to only one channel and the periodic values are stored over one period of oscillation. A special technique is introduced, which reduces both the effort in CPU-time and in computer memory. Results are included for compressor and turbine geometries in sub- and transonic flow.


Sign in / Sign up

Export Citation Format

Share Document