This document summarizes a study on jet impingement cooling for electronic components. Jet impingement is introduced as a promising cooling method for high-power electronics using gas as the coolant. The study aims to analyze jet impingement cooling using computational fluid dynamics (CFD) to evaluate the effect of nozzle diameter on cooling. A geometrical model of the jet and electronic component is created and meshed in ANSYS ICEM before running a steady-state analysis in ANSYS Fluent. Preliminary results are presented for a case with a nozzle diameter of 0.25cm and jet-to-target height of 4cm. Further optimization of diameter, height, and velocity will be investigated.

1. Performance Evaluation Study on Jet
Impingement Cooling for different Flow
and Geometrical Parameters.
Internal Guide, External Guide,
Indu .R Reji R V
Asst.Professor Mechanical Dept.
Mechanical Dept. C E T
LMCST
Presented By,
Akhil Mathan Chackochan
Cyril John
Joel Joy
Mathew Augustine Joseph

2. Contents
• Introduction
• Objectives
• Numerical Methodology
• Case-1
• Results and Discussion
• Conclusion

3. Major Causes Of Electronic Failures

4. Introduction To Jet Impingement
Cooling
• A promising method for high power electronics
• The coolant impinges on the target.
• Gas can be used as the coolant.
• Single jet or multiple jets can be used.
• Requires a small compressor or pump
Industrial applications are drying of food products, textiles,
and paper processing, cooling of turbine blade.

5. • Impinging Jet is a high velocity coolant mass ejected from
hole or slot that impinges on the heat transfer surface
• Characteristic feature of this flow arrangement is an
intensive heat transfer rate between the wall and the fluid.
• It provides an effective means of removing localized heat
loads.

6. Schematic Layout Of An Jet Impinging
6

7. Flow Regions
7
 Free jet region:-
The flow is axial in direction
 Stagnation Region :-
Jet flow is decelerated normal to
the impingement surface and
accelerated parallel to it.
 Wall Jet Region :-
Boundary layers begin to grow

8. Classification of Impinging Jets
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 Cross Sections:
 Circular
 Rectangular
 Confinement:
 Confined – Flow is
confined to a region after
impingement
 Unconfined – Flow is
unconfined after
impingement

9. Selection of coolants
Air as a Coolant
•Simplicity
•Low Cost
•Easy to access
•Reliable
9

10. Objective
To conduct CFD analysis on electronic cooling using jet
impingement
• To study the effect of nozzle diameter on electronic cooling using jet
impingement.
10

11. Geometrical Model

12. After Meshing

13. Parameters
 Jet diameter (D)
 Jet to target spacing (S)
 Reynolds number ( Re)
 Ratio of jet spacing to jet diameter (S/D)
 Flow velocity (V)
13

14. Assumptions
• Flow is steady.
• Three dimensional.
• Radiation heat transfer effects are neglected.
• Thermo physical properties such as specific heat, and thermal
conductivity are constant.
• Heat is generated inside heat sink base at a uniform rate and
can be represented by a constant heat flux.
• Unidirectional heat flow (upward direction).
14

15. Numerical Methodology
SOFTWARES USED
• Domain preparation
ANSYS ICEM 15.0 software
• Analysis
ANSYS FLUENT 15.0 software
15

16. Analysis
Domain preparation ANSYS ICEM 15.0 software
Analysis part is done with ANSYS FLUENT 15.0
 Steady state pressure based analysis is considered.
Material properties are selected from fluent data base.
Operating and boundary conditions are defined .
Values are initialized.
Required sets of data's and contours' are plotted .
16

17. Case 1-
Pipe inlet – Air – Temperature ( 300K)
Velocity inlet ( 10m/s)
Chip – solid
Material selected
Chip – Aluminum.
Radius of jet-0.25cm
Height of impingement-4cm
Chip Dimension-(4*2)cm
17

19. Ansys Fluent-Graphical Representation

20. WORK IN PROGRESS
• To find the optimum diameter among
0.125cm
0.25cm
0.5cm
0.75cm
• To find the optimum heights among
4cm
3cm
2cm

21. FUTURE WORKS TO BE COMPLETED
•To find the optimum velocity
• To perform 3D model analysis

22. THANK YOU