An Object-Oriented Parallel Finite-Volume CFD Code

2008 ◽  
Author(s):  
Dulceneia Becker ◽  
Joa˜o Roberto Barbosa ◽  
Jesuino Takachi Tomita
Keyword(s):  
Finite Volume ◽  
Supersonic Nozzle ◽  
Three Dimensional ◽  
Object Oriented ◽  
Memory Usage ◽  
Application Development ◽  
Programming Techniques ◽  
Fortran 90 ◽  
Oriented Parallel ◽  
Project Objectives

This paper concerns the parallelization and optimization of an in-house three-dimensional unstructured finite-volume computational fluid dynamics (CFD) code. It aims to highlight the use of programming techniques in order to speedup computation and minimize memory usage. The motivation for developing an in-house solver is that commercial codes are general and sometimes simulations are not in agreement with actual phenomena. Moreover, in-house models can be developed and easily integrated to the solver. The original code was initially written in Fortran 77 though the most recent added subroutines include Fortran 90 features. Due to language restrictions and the initial project objectives, issues such as memory usage minimization were not considered. The new code uses an object-oriented paradigm aiming to enhance code reuse and increase efficiency during application development. The parallel code is fully written in Fortran 90 using MPI and hence portable to different architectures. Numerical experiments of typical 3D cases, such as flat plate with uniform incoming flow and a converging-diverging supersonic nozzle, were carried out showing good parallel efficiency. The serial version of the ported code has shown a considerable reduction on the execution time compared to the original code. Convergent solutions agree with the solution of the original code.

Teaching ERP Programming Using SAP ABAP/4

2011 ◽  
pp. 261-282
Author(s):  
Bernard Han
Keyword(s):  
Object Oriented ◽  
Future Trend ◽  
Teaching Approach ◽  
User Needs ◽  
End User ◽  
Application Development ◽  
Teaching Pedagogy ◽  
Hands On ◽  
Programming Techniques ◽  
Module Development

In this chapter, a teaching pedagogy for ERP programming using SAP ABAP/4 is presented. While object-oriented (OO) programming techniques have received increasing attention in new ERP module development, learning and mastering of traditional ABAP/4 code will continue to play an important role especially in maintaining SAP R/3 systems for necessary extensions that are required to meet end-user needs of SAP adopters. The pedagogy presented is essentially a three-threaded teaching approach that involves a stepwise learning of ABAP/4, selective hands-on investigation of SAP R/3 modules, and an accumulative simulation of a simpli?ed R/3 module. A simple ABAP/4 program is also presented to highlight how an online report could be easily generated through using both internal tables and the sample database (?ight) available in SAP R/3. Limitations, suggestions, and future trend of ABAP/4 application development are also addressed with a concluding remark.

Object oriented methods using Fortran 90

1994 ◽  
Vol 13 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Brian J. Dupée
Keyword(s):  
Object Oriented ◽  
Fortran 90 ◽  
Object Oriented Methods

Combined Microstructure and Heat Transfer Modeling of Carbon Nanotube Thermal Interface Materials1

2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Sridhar Sadasivam ◽  
Stephen L. Hodson ◽  
Matthew R. Maschmann ◽  
Timothy S. Fisher
Keyword(s):  
Heat Transfer ◽  
Thermal Resistance ◽  
Finite Volume ◽  
Pressure Dependence ◽  
Matrix Material ◽  
Three Dimensional ◽  
Coarse Grain ◽  
Total Thermal Resistance ◽  
Thermal Interface ◽  
Cnt Arrays

A microstructure-sensitive thermomechanical simulation framework is developed to predict the mechanical and heat transfer properties of vertically aligned CNT (VACNT) arrays used as thermal interface materials (TIMs). The model addresses the gap between atomistic thermal transport simulations of individual CNTs (carbon nanotubes) and experimental measurements of thermal resistance of CNT arrays at mesoscopic length scales. Energy minimization is performed using a bead–spring coarse-grain model to obtain the microstructure of the CNT array as a function of the applied load. The microstructures obtained from the coarse-grain simulations are used as inputs to a finite volume solver that solves one-dimensional and three-dimensional Fourier heat conduction in the CNTs and filler matrix, respectively. Predictions from the finite volume solver are fitted to experimental data on the total thermal resistance of CNT arrays to obtain an individual CNT thermal conductivity of 12 W m−1 K−1 and CNT–substrate contact conductance of 7 × 107 W m−2 K−1. The results also indicate that the thermal resistance of the CNT array shows a weak dependence on the CNT–CNT contact resistance. Embedding the CNT array in wax is found to reduce the total thermal resistance of the array by almost 50%, and the pressure dependence of thermal resistance nearly vanishes when a matrix material is introduced. Detailed microstructural information such as the topology of CNT–substrate contacts and the pressure dependence of CNT–opposing substrate contact area are also reported.

On parallel object oriented programming in Fortran 90

1996 ◽  
Vol 4 (1) ◽  
pp. 27-31 ◽  
Author(s):  
Charles D. Norton ◽  
Viktor K. Decyk ◽  
Boleslaw K. Szymanski
Keyword(s):  
Object Oriented ◽  
Object Oriented Programming ◽  
Fortran 90

Three-Dimensional Parametric Finite-Volume Homogenization of Periodic Materials with Multi-Scale Structural Applications

2018 ◽  
Vol 10 (04) ◽  
pp. 1850045 ◽  
Author(s):  
Qiang Chen ◽  
Guannan Wang ◽  
Xuefeng Chen
Keyword(s):  
Finite Volume ◽  
Three Dimensional ◽  
Functionally Graded ◽  
Attractive Alternative ◽  
Matrix Assembly ◽  
Functionally Graded Composite ◽  
Multi Scale ◽  
Hexahedral Elements ◽  
Stiffness Matrices ◽  
Structural Applications

In order to satisfy the increasing computational demands of micromechanics, the Finite-Volume Direct Averaging Micromechanics (FVDAM) theory is developed in three-dimensional (3D) domain to simulate the multiphase heterogeneous materials whose microstructures are distributed periodically in the space. Parametric mapping, which endorses arbitrarily shaped and oriented hexahedral elements in the microstructure discretization, is employed in the unit cell solution. Unlike the finite-element (FE) technique, the expressions for local stiffness matrices are derived explicitly, enabling efficient global stiffness matrix assembly using an easily implementable algorithm. To demonstrate the accuracy and efficiency of the proposed theory, the homogenized moduli and localized stress distributions produced by the FE analyses are given for comparisons, where excellent agreement is always obtained for the 3D microstructures with different geometrical and material properties. Finally, a multi-scale stress analysis of functionally graded composite cylinders is conducted. This extension further increases the FVDAM’s range of applicability and opens new opportunities for pursuing other areas, providing an attractive alternative to the FE-based approaches that may be compared.

Sign in / Sign up

Export Citation Format

Share Document