Optimization of Heat Transfer Enhancement of a Domestic Gas Burner Based on Pareto Genetic Algorithm: Experimental and Numerical Approach

As an innovative type of passive flow control structure, the protrusion exhibits great potential for heat transfer enhancement. In this paper, genetic algorithm is used for the dimensional optimization of a protruded micro-channel. The protruded micro-channel is studied at four mass-flow rates. In all the cases, thermal performance is selected as the objective function that represents both heat transfer and flow friction. The radius of the protrusion and the distance are selected as the two optimized parameters, and their ranges are decided by physical topologies. The objective function thermal performance is calculated by an auto-CFD batch program. The results shows that there are two peaks of thermal performance values when R and ? change in the cases with flow rates equaling 4 ? 10?5 kg/s and 6 ? 10?5 kg/s, while at the other two flow rates, the thermal performance values increase monotonously. The global optimal solutions for the four flow rates and two local optimal solutions are given in this research, and it is helpful to choose the best design variables to achieve the highest thermal performance. It also can be found that at all the different flow rates, the optimized shape of micro-channel has the same point that (R-?) is nearly 45 ?m in the studied ranges of optimized parameters.

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Computational Analysis of Heat Transfer Enhancement in Square Ducts With V-Shaped Ribs: Turbine Blade Cooling

Journal of Heat Transfer ◽

10.1115/1.1865220 ◽

2005 ◽

Vol 127 (4) ◽

pp. 425-433 ◽

Cited By ~ 24

Author(s):

R. Jia ◽

B. Sunde´n ◽

M. Faghri

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Heat Transfer Enhancement ◽

Turbulence Modeling ◽

Experimental Studies ◽

Numerical Approach ◽

Navier Stokes ◽

Transfer Enhancement ◽

Transfer Coefficients ◽

Sampling Points

Experimental studies have revealed that both downstream and upstream pointing V-shaped ribs result in more heat transfer enhancement than transverse straight ribs in ducts. However, based on the available experimental results, contradiction exists whether the upstream or the downstream pointing V-shaped ribs orientation is superior for better enhancement in heat transfer. Further investigations are thus needed concerning the heat transfer and fluid flow phenomena in ducts with V-shaped ribs to clarify this. In the present investigation a numerical approach is taken and the heat and fluid flow is numerically simulated by a multi-block parallel 3D solver. For turbulence modeling, the v2¯ f-kε model is employed but results from previous EASM calculations are also considered in analyzing and attempting to understand the various experimental data. Large eddy simulations (LES) are also carried to evaluate the accuracy and reliability of the results of Reynolds-averaged Navier-Stokes (RANS) methods and to understand the underlying physical phenomena. It is suggested that the discrepancy between the various experiments most probably is due to the measurement methods, or the number of sampling points. With the TC (thermocouples) technique, a few sampling points are not sufficient to represent the heat transfer behavior in V-shaped ribs, due to the uneven distribution of the heat transfer coefficients.

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