Optimization and Computational Fluid Dynamics - Department of ...

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INPUT FILE Gambit
Fluent
(Parameter values)
journal file journal file
Gambit 2.3
Generation of
geometry
+
mesh
Fluent 6.3
CFD simulation
+
Post−processing
C program on Linux for automatization
Fig. 2.6 Flow chart showing the numerical solution procedure
OUTPUT FILE
(Objective values)
computer codes and is employed in our case to call a C interfacing program
responsible for the evaluation of the objective functions.
2.3.4 Evaluation of the Objectives for Case A
In the present case, this evaluation relies on the commercial software Gambit
[29] for geometry and mesh generation, and Fluent [30] for solving the
flow and energy equations. Therefore, the evaluation of an individual set of
parameters requires four steps:
1. the generation of the computational geometry using the position variables;
2. the generation of an appropriate mesh for the obtained geometry;
3. the CFD simulation, i.e., the solution of the governing coupled equations
for the flow variable and the energy on the mesh generated in the previous
step;
4. the post-processing of the obtained results to extract the values of the
objective functions for these specific design variables.
Steps 1 and 2 are performed using the commercial software Gambit 2.3 [29],
step 3 using the CFD code Fluent 6.3 [30] and step 4 takes place in the
in-house interfacing code.
2.3.4.1 Step 1: Computational Geometry of the Heat Exchanger
Configuration with 4 Tubes
The geometrical constraints are prescribed in terms of lower and upper limits
on the parameters. The positions of the middle points of the four circular
tubes of the heat exchanger are given with their two-dimensional coordinates.
The domain is separated in six non-overlapping zones in x-direction, the first