Thermal Management of High Heat Dissipating Electronic Components- LED Module and Metal Diodes

International Journal on Recent and Innovation Trends in Computing and Communication ISSN: 2321-8169

Volume: 3 Issue: 11 6075 - 6089

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IJRITCC | November 2015, Available @ http://www.ijritcc.org

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Thermal Management of High Heat Dissipating Electronic Components: LED

Module and Metal Diodes

Pal Riya Bipradas Sanchita

ME Student , Dept. Of ETRX, PIIT Engineering College,

Mumbai University, India,

[email protected]

Abstract — Every day, new electronic products such as COB LED lighting products, inverters, metal diodes/rectifier module etc are launched in

the market worldwide. Many of these LED lighting products and high power metal diodes (in the form of rectifier module) come either without

any cooling provision or with low grade cooling provision. Aluminum heat sinks are the most common thermal management hardware solution

in use for majority LED Modules as well as for Metal Diode Rectifier Module. The goal of the work performed and explained in this manuscript

under the title “thermal management of high heat dissipating electronic components: led module and metal diodes” is to first observe and

analyze the extent to which thermal management is achieved by existing Aluminum hardware on a selected LED Module and on Metal Diode

Setups and then developing a new hardware using copper material for the selected LED Module and Metal Diode which will provide an

enhanced thermal management than the existing aluminum hardware solution.

Keywords— Thermal conductivity (k), Thermal Resistance offered by a material (RTH), Source and Sink Junction Resistance (Rthj), Heat

Transfer Rate (Q), Heat flux (q), Aluminum (Al) , Copper (Cu), Heat Sink (H_S).

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I. INTRODUCTION

1.1 LITERATURE SURVEY ON „COB LED MODULE‟ COOLING TECHNOLOGIES :

In an experiment [1] performed by Dan Pound and Richard W. Bonner, thermal management of single LED was conducted

using solid Aluminum and copper substrate (Fig 1). It had Etched LED circuit at the top and a copper heat pipe (with wire

mesh inserted) at the bottom/backside.

Fig 1: Heat Pipe Embedded In PCB

Angie Fan, Y. Sungtaek Ju , Richard Bonner and Stephen Sharratt [2] conducted an experiment where they developed a new

PCB structure. They have developed PCB (printed circuit board) having PHS (passive heat spreader). This PHS PCB has a

copper chamber and at the base of the LED Chip, a copper thermal pad was integrated. Copper chamber has Cu platted FR-4

type envelop. The complete structure (LEDs + Cu thermal pad + Cu FR-4 envelop +Cu chamber) were fitted to „Al‟ heat sink

hardware using a „Cu‟ lid. This development uses a combination of Al and Cu metals as they are very high heat conduction

materials (Fig 2). Inside the Cu chamber, working fluid undergoes evaporation and condensation processes thus managing the

high performance high heat flux LED‟s thermal issue.


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Fig 2: PHS PCB

Another experiment (Fig 3) was conducted on multi LED system by Mehmet Kaya [3] , where he used 2 different types of

LED system. One having single LED of 30W and other configuration of 2X15W. He presented the temperature difference of

LED Substrate in both the LED configurations using the integrated fin heat sink design with and without a fan and also with a

heat pipe integrated cooling structure. Results that he obtained are given below in the form of graphical representation.

Fig 3: Left:An Integrated Multi-Fin Heat Sink Design With A Fan and heat pipe. Right: Graph

1.2 LITERATURE SURVEY ON „METAL DIODE‟ COOLING TECHNOLOGIES :

Experiment (Fig 4) conducted by Martin März, illustrates the prototype of a water-cooled technique. This technology

achieves its nominal output power with a coolant temperature of up to 105°C. All power components are thermally coupled

to the heatsink, the power board (FR-4) is double-sided 105μm and copper conducts currents of more than 200A. The

efficiency exceeds 90% over a wide power range. The power density is about 3.5W/cm3.


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Fig 4: Complete Setup Of Power Converter Having High Power Diodes

Another Experiment (Fig 5) conducted by Martin März on power converters illustrates the use of Copper thermal „vias‟.

Since PCBs offers very bad thermal conduction, these copper sleeves can be inserted inside the PCB exactly lying below the

power semiconductor device mounted at the upper side of PCB. Copper sleeves or vias can be used for semiconductors such

as high current metal diodes and other forms of high power semiconductor devices like SCRs, TRIACS, DIACs, high power

BJTs etc.

Fig 5: Use Of Copper Vias To Cool High Power Diodes

II. DESIGNING OF THE NEW COOLING STRUCTURE USING COPPER METAL STRIP:

1.3 DESIGNING :

New cooling unit (shown in fig 6,C) which has been designed using copper [6], consist of 2 parts. First part is the “corrugated

triangular fins” structure (fig 6,A) and the second part is the “base”(fig 6,B). Number of fins (N), height of fins (H), spacing

between fins (Pf), fin thickness (Ft or (Ta= Tb1=Tb2)) and base plate thickness (b) , base plate length (w) & width (L) will

vary from one application to other. The structure shown in (fig 6,C) is a long running structure. This complete structure can

be folded into any geometrical shape such as one shown in cylindrical form (fig 6,D). Base plate acts as an extra supporting

part which will provide mechanical support as well as it will improve thermal conduction. If number of fins are less then

height is to be increases if heat flux value is high. Even for high heat flux if number of fins are more, then height of fins

should be kept low but spacing between fins must be taken care.


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Fig 6: (A) shows the corrugated triangular fins structure . (B) Base plate. (C) Complete unit. (D) Square/Rect Structure. (E)

Circular/ Cylindrical Structure

From above fig (6,C), Two conditions/cases are illustrated for heat transfer to take place through corrugated structure. The

T1, T2 &T3 represents highest temperature, mid temperature and low temperature respectively The flow of heat (Q) will

always happen from higher temperature location to lowest temperature location in contact.

Thus Q = f1(T1, T2, strip geometry, material) (1)

The relation between T1 and T2 is in the form of temperature difference (T1-T2) and „x‟ is the separation distance between

T1 & T2.

Q = f2 (T1-T2, strip geometry, material) (2)

Case 1:

If (T1-T2) = 0 (i.e.: when T1 = T2)

Then Q = 0 (means no heat/ thermal transfer rate is being taking place between p1 and p2 points)

Case 2 :

If T1>T2

Then Q>0 (means heat transfer rate increases)

Q α 𝐴.(𝑇1−𝑇2)

𝐿

Q = 𝐾.𝐴.(𝑇1−𝑇2)

𝐿

Q = - 𝐾.𝐴.(𝑇2−𝑇1)

𝐿 (unit: watts)

Qx = - K.A𝑑𝑇

𝑑𝑥 (3)

This is the heat transfer at x direction.

For y and z direction (in 3D representation), Q is given as:

Qy = - K.A𝑑𝑇

𝑑𝑦 (4)

Qz = - K.A𝑑𝑇

𝑑𝑧 (5)

Note: for a very thin copper strip, heat conduction in 3D form can be neglected. Heat flow in any 1 direction can be

considered for simplicity.

Heat Flux (q) is defined as the „rate of flow of heat‟ and Critical heat flux is the „thermal limit of a phenomenon where a

phase change occurs during heating‟.

q = 𝑄

𝐴 (6)

2.1.2 ROLE OF INDIVIDUAL PARAMETERS ON THERMAL CONDUCTIVITY

Thermal Conductivity (K) = 𝑄 .𝐿

𝐴.△𝑇 (7)

1. Temperature difference (△ 𝑇) :

Greater the temperature difference between the two ends of the bar or the strip, greater will be the rate of heat flow.

Q α △ 𝑇 (8)

2. Cross-sectional area (A):

A bar twice as wide conducts twice the amount of heat.


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Q α A (9)

3. Separation length/ distance (L) :

Rate of heat transfer is always inversely proportional to the length of the bar.

Q α 1

𝐿 (10)

4. Time (t):

Heat flow (Q) directly depends on the amount of time that passes. Twice the time, twice the heat.

2.1.3 THERMAL RESISTANCE (Rth) :

There is an electrical analog with conduction heat transfer [5]. The analog of “Q” or “P” is current “I” , thermal profile “△T”

is voltage difference & thermal resistance “Rth” is Electrical resistance “R”.

Fig 7: Electrical Model and Thermal Model Relation

Ohm‟s Law :

Voltage = Current x Resistance

V= IxR

Fourier‟s Law:

△T= QxRth

Then

Rth = △T/Q

Q = 𝑇1−𝑇2

𝑅𝑡ℎ or

𝑇2−𝑇3

𝑅𝑡ℎ (11)

2.2 TECHNOLOGY USED TO DEVELOP CORRUGATED COOLING UNIT USING COPPER

Technology [4] which has been decided to be used is “Corrugated Triangular Fin Technology”. Where ever it is required

to have high fin density on a restricted surface area at low weight and low manufacturing cost, corrugated fin technology is

given much more importance compared to other technologies such as :

Extruded

Bonded

Die-casting

Skiving

Machining

Forging

Stamping

Folded fins are manufactured by folding continuous strip of copper or aluminum in either a square wave , rect wave , u-

wave or in a triangular wave patterns. After folded fins are manufactured, one can attach a base strip which helps increasing

the heat transfer surface area. Below fig 8 represents the machine used to form triangular corrugated fin structure.


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Fig 8: Left: Complete View Of The Manually Controlled Corrugated Machine. Right : Triangular Press Region Of The

Machine.

III. EXPERIMENT ON COB LED MODULE : WITH NO COOLING MECHANISM , WITH ALUMINUM

COOLING STRUCTURE & WITH COPPER COOLING STRUCTURE

For this experiment, 6W White Light COB LED has been selected.

Technical Specification of selected 6W White Light COB LED:

1. MODEL: 06-12

2. Input : AC220-240V,50/60Hz

3. Output:DC12-24V max

4. Constant current: 300mA

5. Max Temperature withstand capacity :750C

Fig 9: Left : COB LED Base . Right : Driver Circuit.

In current market, Aluminum heat sink is the only available cooling solution for COB LEDs. In this manuscript, new

hardware cooling structure using copper material is placed. Below TABLE 1 provides the complete specification of existing

cooling “Al” hardware and newly developed “Cu” hardware structures.

TABLE 1: GEOMETRIC DATA OF AVAILABLE “Al” AND DEVELOPED “Cu” HEAT SINK STRUCTURE FOR 6W COB

LED

Sr

No

Parameters Aluminum Heat Sink

Specifications

Copper Heat Sink

Specifications

1 Heat sink material used “Al” “Cu”

2 Type of structure Parallel fins Cylindrical

structure

Corrugated triangular fin

structure

3 Size of the region where this cooling unit is

placed

r = 30mm (i.e. circular region) r = 30mm (i.e. circular region)

4 Weight (LED Module + “Al” structure) 155gm 145gm

5 „Al‟ heat sink attachment/base plate thickness 1 mm 1mm

6 Number of parallel fins 30 10

7 Height limit 35mm 27mm

8 Power Applied

6W 6W


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Based on the above given specifications of Copper structure, below is the pictorial comparison of COB LED module

without any cooling provision , COB LED module with aluminum structure provided for cooling (this is ready made i.e

available in the current market) and COB LED module with Copper cooling structure.

Fig 10: Left : 6Watts COB LED Module with no cooling unit attached to it.. Middle : Complete LED Module + „Al‟ Heat sink

structure Setup. Right : COB LED module with Copper cooling structure .

Test on chip on board LED was conducted; maximum temperature rise of the board was noted to be 700C without

implementing any cooling provision. This test was conducted for 105minutes. No rise in the board‟s temperature was

noticed above 700C which marked the saturation temperature zone for this LED module without any cooling provided.

When the same test was repeated with aluminum heat sink shown in the above figure 10, only 30C reduction in the LED

board‟s temperature was seen i.e:670C. Temperature test done with new developed copper heat sink, reduced LED board‟s

temperature to 420C i.e 25

0C difference.

Complete experimental data is depicted in TABLE 2,3 & 4 below.

TABLE 2: 6WATTS COB LED TEMPERATURE MEASUREMENT (NO COOLING PROVISION)

Time (min) LED PCB Temp with

no cooling provision

(0C)

(initial ) 0 30

5 37

10 40

15 45

20 48

25 53

30 55

35 57

40 58

45 60

50 60

55 63

60 65

65 65

70 68

75 69

80 70

85 70

90 70

95 70 100 70

105 70

Experiment performed at Room temperature of: 300C

TABLE 3: 6WATTS COB LED TEMPERATURE MEASUREMENT (WITH ALUMINUM COOLING PROVISION)


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Time

(Min)

Air_Heat-Sink

Junction Temp (0C)

Temp Of Inner

Core Of Heat Sink

(0C)

Light Source PCB

Temp

(0C)

(initial ) 0 30 30 30

5 31 31 36

10 31 36 51

15 34 37 58

20 36 38 60

25 39 40 62

30 39 41 64

35 39 41 65

40 40 42 65

45 40 42 65

50 40 43 65

55 41 44 66

60 43 44 66

65 43 45 66

70 44 46 66

75 45 46 66

80 45 47 66

85 47 49 67

90 47 49 67

95 48 50 67

100 48 50 67

(Final) 105 48 50 67


TABLE 4: 6WATTS COB LED TEMPERATURE MEASUREMENT (WITH COPPER COOLING PROVISION)

Time

(Min)

Air_Heat-Sink

Junction Temp

(0C)

Temp Of Inner

Core Of Heat Sink

(0C)

Light Source PCB

Temp

(0C)

(initial ) 0 30 33 32

5 32 44 35

10 34 44 42

15 33 44 43

20 35 45 42

25 36 41 42

30 33 38 45

35 34 37 43

40 37 42 42

45 36 38 45

50 34 42 46

55 34 43 46

60 36 45 46

65 35 40 44

70 34 44 47

75 36 44 49

80 34 42 42

85 34 39 42

90 33 42 42

95 33 42 42

100 33 42 42

(Final) 105 33 42 42



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Fig 11: Graph Showing COB LED Module‟s Temperature With No Cooling Provision (Red Line), With Aluminum Heat Sink

(Orange Line) & With Developed Copper Heat Sink (Blue Line).

3.1 CALCULATIONS :

3.1.1 HEAT FLUX (q) of COB –LED :

Fig 12: Showing the Space Consumed By 1 LED

Diameter of LED = 8mm = 0.8cm

Radius = 0.4cm

Area Under 1LED Chip = 3.14 x 0.4 x 0.4 = 0.5cm2

For 6 LEDs, area = 3cm2

Power consumed by LED Module = 6W

Heat flux = power utilized / area = 2W/cm2

3.1.2 “RTH” CALCULATION :

Refer TABLE 3 & 4:

This is to be measured between heat sink’s core (inner/fin base) and heat sink_Air junction Temperature (outer/fin tip).

Formula = Higher Temp −Lower Temperature

Power =

Temp of inner HeatSink Core – HeatSink _Air Junction Temp

Power

TABLE 5 : “RTH” OFFERED BY ALUMINUM AND COPPER STRUCTURES

Sr No Time

(min)

RTH Offered By Aluminum Heat Sink

(0C/W)

RTH Offered By Copper Heat

Sink (0C/W)

1 10 36−31

6 =

5

6 = 0.833

44−34

6 =

10

6 = 1.66

2 35 41−39

6 =

5

6 = 0.333

37−34

6 =

3

6 = 0.5

3 45 42−40

6 =

2

6 = 0.33

38−36

6 =

2

6 = 0.33

4 60 44−43

6 =

1

6 = 0.166

45−36

6 =

9

6 = 1.5

5 85 49−47

6 =

2

6 = 0.333

89−34

6 =

5

6 = 0.888

6 105 50−48

6 =

2

6 = 0.33

42−33

6 =

9

6 = 1.5


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3.1.3 HEAT SOURCE AND HEAT_SINK JUNCTION RESISTANCE CALCULATION ( Rthj):

When a heat sink and heat source are in contact with each other, resistance towards the flow of heat path is developed at

their junction. This junction resistance value do not remain constant. It rises to a higher value from low value with

respect to time and then falls again with the flow of time. Rthj has been calculated for certain selected time (min) such as

5, 10, 20, 30, 45, 60, 75, 90, 105 so as to keep illustration simple. This is well illustrated with the below calculations of

Junction Resistance (Rthj) in TABLE 6

Refer TABLE 3 & 4:


Power

TABLE 6 : “Rthj” OFFERED BY HEAT SOURCE AND HEAT SINK (ALUMINUM & COPPER)

Sr No Time (min) Rthj (Between COB LED board &

Core of Al heat sink junction)

(0C/W)

Rthj (Between COB LED board &

Core of Cu heat sink junction) (0C/W)

1 5 36−31

6 = 0.833

44−35

6 = 1.5

2 10 51−36

6 = 2.5

44−42

6 = 0.33

3 20 60−38

6 = 3.666

45−42

6 = 0.50

4 30 64−41

6 = 3.833

45−38

6 = 1.166

5 45 65−42

6 = 3.833

45−38

6 = 1.166

6 60 64−44

6 = 3.666

46−45

6 = 0.166

7 75 66−46

6 = 3.333

49−44

6 = 0.833

8 90 67−49

6 = 3.00

42−42

6 = 0 = un-measurable

9 105 67−50

6 = 2.833

42−42

6 = 0 = un-measurable

Fig 13: Graphical Representation Of “Rthj” Offered By Heat Source And Heat Sink [Aluminum (Red line) & Copper (blue

line)]

Graph in fig 13 & Table 6 shows that copper heat sink offers less thermal resistance path than aluminum heat sink when

attached with the heat source (i.e COB LED).

3.1.4 COST ESTIMATION :

1. Cost of 1Kg Al = INR 97.795

Cost of 1Kg Cu = INR 351.82

Aluminum used to form this aluminum heat sink shown in fig 10 = 45grams.

Cost of this heat sink = INR 4.4

2. Copper used to form this new heat sink shown in fig 10 = 35grams.



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Conclusion : Cost difference is INR 7.9 . This cost is not very high and COB LED with this developed Cu heat sink is

affordable if we see from the increased lifespan of COB LED Module‟s point of view.

IV. EXPERIMENT ON HIGH VOLTAGE HIGH CURRENT METAL DIODE MODULE : WITH NO COOLING

MECHANISM , WITH ALUMINUM COOLING STRUCTURE & WITH COPPER COOLING STRUCTURE

Below fig 14 (left) represents the block diagram of high current metal diode in the form of metal rectifier module where

aluminum heat sink is used to manage thermal level of metal diodes whereas ( fig 14, right) represents the block diagram of

high current metal diode in the form of metal rectifier module where copper heat sink is used to manage thermal level of

metal diode.

Fig 14:Block Diagram Of Metal Diode In The Form Of A Bridge Rectifier Setup Where Left : Metal Diode With Aluminum

Heat Sink . Right: Metal Diode With Newly Developed Copper Heat Sink/ Cooling Unit

Technical detail of the above mention circuit is given below:

1. Main line voltage = 240V

2. Step down transformer = 12V3A

3. Number of high current metal diodes used = 4

4. Metal diode max. current limit = 12 A -16 A

5. Load : DC Bulb


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Figure 15: Left: This Figure Shows The Aluminum Heat Sink For Metal Diode Which Is Currently Available In The Market.

Middle: Newly Developed Copper Heat Sink/Cooling Unit For Metal Diode. Right : Metal diode on PCB board. Bottom : Solder

side view of the PCB with Cu Heat Sink

TABLE 7: GEOMETRICAL SPECIFICATION

Sr No Parameters Copper Heat Sink

(Developed)

Aluminum Heat Sink

(Existing)

1 Base height (b) 2 mm 3mm

2 Base length (w) 31mm 35mm

3 Base width (L) 26mm 17mm

4 Number of fins (N) 3 8

5 Fin thickness (Ft) 0.1mm 2mm

6 Fin height (H) 15mm 5mm

7 Fin neck width Not present 10mm

8 Genuine height / vertical height 18mm 26mm

9 Weight 18gm 30gm

10 Setup Power consumption 36W 36W

Experiment was performed at room temperature of 300C where aluminum and copper heat sink were tested for 65minutes.

Aluminum heat sink‟s temperature reached up to 340C which marks the saturated temperature zone for this heat sink.

Temperature reached by metal diode in this experiment was 390C. This proves that heat absorption rate of aluminum heat

sink is slow this resulted main component i.e. metal diode‟s temperature to reach higher value than Al heat sink‟s

temperature.

In the case where copper heat sink was applied, metal diode‟s temperature reached a value of 350C where as copper heat

sink‟s temp was measured to be 370C. This proved that, this designed copper heat sink structure is perfect to cool metal

diode as this structure provides much better heat transfer/ conduction path for metal diode. Copper structure raised its temp

keeping diode‟s temp low. When no cooling provision was implemented in this high voltage high current metal diode then

it reached a saturated temperature zone of 490C. This is well depicted in below TABLE 8.

Table 8: TEMPERATURE READING OF METAL DIODE WITH NO COOLING, WITH ALUMINUM HEAT SINK AND

COPPER HEAT SINK.

Time

(min)

Metal Diode‟s Temp

(0C) with no cooling

provision

Performance with aluminum heat sink Performance with copper heat sink

Metal Diode Temp (0C) Al heat sink‟s Temp (0C) Metal Diode Temp (0C) Cu heat sink‟s Temp (0C)

Initial 0.00 30 30 30 30 30

5 34 30 32 33 30

10 35 30 29 34 34

15 36 29 30 33 34

20 39 33 31 33 34

25 40 33 31 34 35

30 40 37 35 35 36

35 46 37 35 36 35

34 49 38 36 36 35

45 49 39 37 36 35

50 49 37 35 37 35

55 49 38 36 34 37

60 49 39 34 37 36

65 49 39 34 35 37


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Fig 16: Represents Metal Diode‟s Temperature : Without Cooling Implementation (Red Line) , With Aluminum Heat Sink

(Orange Line) , With Copper Heat Sink (Blue Line)

4.1 CALCULATION :

4.1.1 HEAT FLUX OFFERED BY MEAT DIODE:

1. Diameter of 1 Metal diode = 10mm = 1 cm

2. Radius = 5mm = 0.5cm

3. Area Under 1 Metal diode = 3.14x 0.5x 0.5 = 0.785cm2

4. For 4 Metal diode, area = 3.14cm2

5. Power consumed by Metal diode Module = 36W

6. Heat flux = power utilized / area = 11.46W/cm2

4.1.2 HEAT SOURCE AND HEAT_SINK JUNCTION RESISTANCE CALCULATION ( Rthj):

When a heat sink and heat source are placed one above the other, resistance towards the flow of heat path is developed at

their junction. This junction resistance value do not remain constant. Rthj has been calculated for certain selected time (min)

such as 10, 20, 30, 40, 50 & 60 so as to keep illustration simple. This is well illustrated in below calculations of Junction

Resistance (Rthj) in TABLE 9

Refer TABLE 8:


Power

TABLE 9: “Rthj” OFFERED BY HEAT SOURCE AND HEAT SINK (ALUMINUM & COPPER)

Sr No Time (min) Rthj (Between COB LED board & Core

of Copper heat sink junction) (0C/W)

Rthj (Between COB LED board &

Core of Al heat sink junction) (0C/W)

1 10 34−34

36 = 0 un-measurable

37−32

36 = 0.138

2 20 34−33

36 = 0.027

40−35

36 = 0.138

3 30 36−35

36 = 0.027

41−36

36 = 0.138

4 40 36−35

6 = 0.027

41.9−37

36 = 0.136

5 50 37−35

36 = 0.05

41.9−37

36 = 0.136

6 60 37−36

36 = 0.027

41.9−37

36 = 0.136


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Fig 17: Rthj Graphical Representation.

Graph in fig 17 & Table 9 shows that developed copper heat sink offers less thermal resistance path than aluminum heat sink

when attached with the heat source (i.e metal diode).

4.1.3 COST ESTIMATION :

1. Cost of 1Kg Al = INR 97.795

Cost of 1Kg Cu = INR 351.82

Aluminum used to form this aluminum heat sink shown in fig 15 = 30grams.


2. Copper used to form this new heat sink shown in fig 15 = 18grams.


Conclusion : Cost difference is INR 3.994 . Again, this cost is not very high and Metal diode with this developed Cu heat

sink is affordable if we see from the increased lifespan of Metal Diode point of view.

V. CONCLUSION

Test on the LED module was carried out for 105 minutes. When the copper heat sink was tested on the COB LED Module,

showed improved thermal management performance over aluminum heat sink. Copper heat sink (cooling unit) was able to

reduce the COB LED module‟s temperature to 420C where as aluminum heat sink was capable of reducing the temperature

up to 670C.When aluminum and copper heat sink was tested on metal diode module for 65minutes, aluminum heat sink

reduced metal diode‟s temperature to 390C where as copper heat sink was capable of reducing this temperature till 35

0C.

This proves that the heat conduction rate of aluminum heat sink is slow compared to copper heat sink. Thus designed copper

heat sink structure is perfect to cool metal diode module as well as COB LED module as this copper structure provides much

better heat transfer/ conduction path.

REFERENCES

[1] Dan Pound, Richard Bonner III, “High Heat Flux Embedded in MCPCB for LED Thermal Management” ,Advanced

Cooling. Technology, 14th

IEEE ITHERM Conference, ppr 267-271, 2014.

[2] Angie Fan, Richard Bonner, Stephen Sharratt and Y. Sungtack Ju, “An Innovative Passive Cooling Method for High

Performance LED”, IEEE 28thSEMI-THERM symposium, 2012.

[3] Mehmet Kaya, “Experiment Study On Active Cooling Systems Used For Thermal Management Of High Power

Multichip Light Emitting Diodes”, Dept. of Mechanical Engineering, The Scientific World Journal, Vol 2014,

ID:563805,7 pages.

[4] Mukesh Kumar , Anil Kumar , Sandeep Kumar,“OPTIMUM DESIGN AND SELECTION OF HEAT SINK”,

International Journal of Application or Innovation in Engineering & Management , Volume 2, Issue 3,ppr 541-549,

March 2013.

[5] S. Lee, “Optimum Design and Selection of Heat Sinks,” Proceedings of 1 lth IEEE Semi-Therm Symposium, pp. 48-54,

1995.

[6] Jafar Mahmoudi * Jussi Vaarno“Copper Heat Sink Design” , Outokumpu Research Center , Finland.


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AUTHOR :

Er. PAL RIYA BIPRADAS SANCHITA received Bachelor Of Engineering in Electronics from PIIT (Pillai Institute Of

Information Technology, Engineering, Media Studies & Research) under Mumbai University. Currently pursuing Master of Engineering. Her

research areas are Power Electronics and Optical Communication. She is the author of (1) „Free Space Light Communication‟. (2) „Negative

Role of Atmosphere On Free Space Light Communication‟. (3) „Heat in Electronic Circuits and Material Selection Criteria for Cooling

Solutions‟, (4) „Measure Of Heat Conduction Through Copper‟, (5) HY510 Grease: Maximum Temperature Support And Its Application In

Cob Led Heat Management , (6) PTC-Cu Heat Sensor & Its Application In Inverter‟s Thermal Testing & (7) Corrugated Technology based

Copper Heat Exchanger for Efficient Thermal Management of Inverter System.

Thermal Management of High Heat Dissipating Electronic Components- LED Module and Metal Diodes

Documents