Parametric analysis of a round jet impingement on a heated plate

An effective method for performing the thermal optimization of stationary and rotating MCM disks with an unconfined round-jet impingement under space limitation constraint has been successfully developed. The design variables of stationary and rotating MCM disks with an unconfined round-jet impingement include: the ratio of jet separation distance to nozzle diameter (H/d), steady-state Grashof number (Grs), jet Reynolds number (Rej), rotational Reynolds number (Rer). The total experimental cases for stationary and rotating MCM disks are statistically designed by the Central Composite Design (CCD) method. In addition, a sensitivity analysis, the so-called ANOVA, for the design factors has been performed. In the stationary MCM disk with an unconfined round-jet impingement, the contribution percentage of jet Reynolds number on the thermal performance is 95.86%. The effect of jet Reynolds numbers on chip temperature distribution is more significant than that of the H/d ratio and steady-state Grashof number. In rotating MCM disk with an unconfined round-jet impingement, the effect of jet Reynolds number, which has the contribution percentage of 91.81%, dominates the thermal performance. Furthermore, the comparisons between the predictions by using the quadratic Response Surface Methodology (RSM) and the experimental data are made. The maximum deviations for transient stagnation Nusselt number and transient average Nusselt number for the cases of stationary MCM disk are 10.05% and 11.82%, respectively; and 9.41% and 12.44% for the cases of rotating MCM disk, respectively. Finally, with the Sequential Quadratic Programming (SQP) technique, a series of thermal optimal designs under space limitation constraint H/d≤12 has been efficiently performed. Comparisons between the numerical optimization results and the experimental data are made with a satisfactory agreement.

Download Full-text

Effect of Thermal Boundary Condition on Heat Dissipation due to Swirling Jet Impingement on a Heated Plate

Journal of Physics Conference Series ◽

10.1088/1742-6596/395/1/012039 ◽

2012 ◽

Vol 395 ◽

pp. 012039

Author(s):

Karl J Brown ◽

Gerry Byrne ◽

Tadhg S O'Donovan ◽

Darina B Murray

Keyword(s):

Boundary Condition ◽

Heat Dissipation ◽

Jet Impingement ◽

Thermal Boundary Condition ◽

Heated Plate ◽

Swirling Jet

Download Full-text

Numerical Investigation of Impingement Heat Transfer Enhancement on a Flat Plate with an Attached Porous Medium

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.477 ◽

2011 ◽

Vol 312-315 ◽

pp. 477-482 ◽

Cited By ~ 2

Author(s):

Pey Shey Wu ◽

Yi Wen Lo ◽

Fong Chia Cheng

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Flat Plate ◽

Numerical Models ◽

Thick Layer ◽

Jet Impingement ◽

Heat Transfer Process ◽

Heated Plate ◽

Impingement Heat Transfer ◽

Hole Geometry

The enhancement of impingement heat transfer on a flat plate covered with a thick layer of porous medium with or without a center hole was numerically investigated. The renormalization group turbulence model is selected for the fluid region while Forchheimer extended Darcy’s model is used for porous region. The numerical models were justified by comparisons with available experimental data. Computational results show that an attached porous medium with a center hole can effectively enhance jet impingement heat transfer while an attached thick porous layer without a center hole has detrimental effect. The physics of these results are supported and well explained by the detailed flow patterns. The most influential parameters in this heat transfer process include the jet Reynolds number and the center hole geometry (hole depth and jet-to-hole diameter ratio). A good hole geometry should well trap the jet and direct the coolant along the heated plate.

Download Full-text

Comparison of Various RANS Models for Impinging Round Jet Cooling From a Cylinder

Journal of Heat Transfer ◽

10.1115/1.4043304 ◽

2019 ◽

Vol 141 (6) ◽

Cited By ~ 3

Author(s):

Ketan Atulkumar Ganatra ◽

Dushyant Singh

Keyword(s):

Heat Transfer ◽

Numerical Analysis ◽

Turbulence Model ◽

Three Dimensional ◽

Turbulence Models ◽

Jet Impingement ◽

Target Surface ◽

Point Of View ◽

Nozzle Diameter ◽

Round Jet

The numerical analysis for the round jet impingement over a circular cylinder has been carried out. The v2f turbulence model is used for the numerical analysis and compared with the two equation turbulence models from the fluid flow and the heat transfer point of view. Further, the numerical results for the heat transfer with original and modified v2f turbulence model are compared with the experimental results. The nozzle is placed orthogonally to the target surface (heated cylindrical surface). The flow is assumed as the steady, incompressible, three-dimensional and turbulent. The spacing between the nozzle exit and the target surface ranges from 4 to 15 times the nozzle diameter. The Reynolds number based on the nozzle diameter ranges from 23,000 to 38,800. From the heat transfer results, the modified v2f turbulence model is better as compared to the other turbulence models. The modified v2f turbulence model has the least error for the numerical Nusselt number at the stagnation point and wall jet region.

Download Full-text

Heat-Transfer Optimization for Multichip Module Disks With an Unconfined Round Air Jet Impingement

Journal of Electronic Packaging ◽

10.1115/1.2804089 ◽

2007 ◽

Vol 129 (4) ◽

pp. 411-420

Author(s):

Y. C. Lee ◽

C. J. Fang ◽

M. C. Wu ◽

C. H. Peng ◽

Y. H. Hung

Keyword(s):

Heat Transfer ◽

Reynolds Number ◽

Design Method ◽

Jet Impingement ◽

Separation Distance ◽

Multichip Module ◽

Programming Technique ◽

Grashof Number ◽

Round Jet ◽

Air Jet

An effective method for performing the thermal optimization of stationary and rotating multichip module (MCM) disks with an unconfined round-jet impingement under space limitation constraint has been successfully developed. The design variables of stationary and rotating MCM disks with an unconfined round-jet impingement include the ratio of jet separation distance to nozzle diameter, Grashof number, jet Reynolds number, and rotational Reynolds number. The total experimental cases for stationary and rotating MCM disks are statistically designed by the central composite design method. In addition, a sensitivity analysis, the so-called analysis of variance, for the design factors has been performed. Among the influencing parameters, the jet Reynolds number dominates the thermal performance, while the Grashof number is found to have the least effect on heat-transfer performance for both stationary and rotating cases. Furthermore, the comparisons between the predictions by using the quadratic response surface methodology and the experimental data for both stationary and rotating cases are made with a satisfactory agreement. Finally, with the sequential quadratic programming technique, a series of thermal optimizations under multiconstraints—such as space, jet Reynolds number, rotational Reynolds number, nozzle exit velocity, disk rotational speed, and various power consumptions—has been systematically explored and discussed.

Download Full-text