Passive radiators for satellites for Space Explorations

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Thermal Analysis of Passive Radiator for Inter-Planetary Space Applications

Presented By

Shailesh Kumar Singh Rajput

Abhishek DorikYash Dave

Bijank ModiDipak Patel

Guided ByProf. Harshal Shukla

OverviewLiterature SurveyPaper PresentedObjectiveIntroductionATCS & PTCSEnvironmental LoadsGoverning Equations Modeling, Simulation and Boundary ConditionsResultsConclusionsAnnexure

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Sr. Paper / Book Author / Editor Conclusions

1Spacecraft Thermal Control HandbookVol. 1: Fundamental Technologies.

David G. Gilmore

Basics of Thermal control systems, Space Radiators and Environmental Loads and Operating conditions of the Satellite.

2Design of Geosynchronous Spacecraft

Brij N. Agrawal

Thermal control of Spacecraft, Heat Transfer governing laws and different types of Thermal Control Strategies.

3Thermal Control System of the Moon Mineralogy Mapper Instrument

Jose I. Rodriguez(JPL)

Passive Thermal Cooling Systems, Coatings, MLI

4The Moon Mineralogy Mapper (M3) on Chandrayaan-1

Alok Chatterjee (JPL)

Multi Layer Insulation (MLI)

Literature survey

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Paper PresentedPresented Paper Titled:

“Thermal Analysis of Passive Radiators for Inter-Planetary Space Applications”

In the International Conference:“Engineering: Issues, Opportunities and

Challenges for Development”On: Saturday, 9th April, 2016

ISBN: 978-81-929339-3-1

objective

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Conduct Parametric analysis to understand the effects of change in the values of parameters like Radiator Area and Thickness over the heat transfer rate from a Satellite.

We aim at providing suitable design guidelines for maximizing the dissipation of heat generated inside the satellite to space by using passive radiators.

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Introduction

Thermal Control SystemActive Thermal Control System

Passive Thermal Control System

Allowable Temperature LimitsHeat Produced by Electronic Systems

Heat MUST be dissipated to spaceHOW??

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Active THERMAL CONTROL SYSTEM(ATCS)

Used where Narrow Temperature range are to be maintained

Uses electric power input

Heaters, coolers, coolant storage system used

Moving Parts and fluids involved

Heavy and costly cooling system

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PASSIVE THERMAL CONTROL SYSTEM(PTCS)

NO Moving Parts

NO Moving Fluids

NO Electric Power Input

Geometrical Configurations

Thermo-Optical Properties of Surface

Thermal Insulations

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Environmental LoadsSolar Flux

Direct sunlight is the dominating source of heating on the satellite surface.

AlbedoIt is the sunlight reflected off a planet’s surface.

Planet ShineInfrared energy emitted by a planet by the virtue of its own temperature.

SOLAR FLUX

PLANET SHINE

ALBEDO

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Governing EquationsSteady - stateHeat Balance Equation:

[Heat Radiated] = [Heat Absorbed]+[Instrumental Heat Dissipation]

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Governing EquationsTransient state

Based on Lumped Parameter Analytical Method, Heat Balance equation for each node:

Neglecting Albedo and Earth Radiation

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Case Study: Flat Plate Radiator Modeling of Radiator

DissipatorFlat Plate Radiator

Thermal StrapPackage bodyWith MLI

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Device Material Dimensions (mm)

Thermo-optical Properties

IR Solar

Package Aluminium 6061

300×150×300 - -

Dissipator Stainless Steel 30×40×50 - -Thermal

Strap Copper - - -

Radiator Aluminium 6061 (Variable) ε =

0.85 α = 0.4

MLI - - ε = 0.7 α = 0.45

model specifications

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Meshing and simulation

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Bottom face of Package = 20o CThermal Coupling between Dissipator and base

of package: R= 60 C/WThermal Coupling between Dissipator and

Thermal Strap: h= 300 W/m2 CThermal Coupling between Thermal Strap and

Radiator: h= 300 W/m2 CCoupling between MLI and Package: h=0.03

W/m2 C

Boundary conditions applied

300×150×2; Q=3.75 WSr. No. Part Min. Temp Max. Temp

1 Radiator 596.70 602.432 Dissipator 514.15 544.053 Thermal Strap 547.22 581.224 Package 20.00 59.00

results

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resultsSr. Dimension Part

Steady State Condition Transient ConditionsDissipation

Min. Temp Max. Temp Min. Temp Max. Temp

1 300*150*2

Radiator 596.70 602.43 20.00 208.02

3.75Dissipator 514.15 544.05 20.00 189.18

Thermal Strap 547.22 581.22 20.00 197.53

Package 20.00 59.00 20.00 72.17

2 300*150*2

Radiator 1299.19 1304.88 20.00 412.61

15Dissipator 1182.87 1254.07 20.00 442.06

Thermal Strap 1255.83 1283.72 20.00 420.57

Package 21.52 59.00 20.00 72.17

3 300*150*3

Radiator 596.85 600.64 20.00 218.95

3.75Dissipator 514.15 544.05 20.00 204.79

Thermal Strap 547.22 581.22 20.00 213.78

Package 20.00 59.00 20.00 72.17

4 300*150*3

Radiator 1299.33 1303.12 20.00 401.73

15Dissipator 1182.86 1254.06 20.00 441.77

Thermal Strap 1248.06 1283.70 20.00 419.45

Package 20.00 59.00 20.00 72.17

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resultsSr. Dimension Part

Steady State Condition Transient ConditionsDissipation

Min. Temp Max. Temp Min. Temp Max. Temp

5 350*200*2

Radiator 725.24 733.14 20.00 240.82

3.75Dissipator 612.27 653.20 20.00 221.75

Package 20.00 58.30 20.00 71.60

Thermal Strap 667.76 704.12 20.00 233.65

6 350*200*3

Radiator 725.44 730.664 20.00 229.62

3.75Dissipator 612.26 653.19 20.00 215.28

Package 20.00 58.30 20.00 71.60

Thermal Strap 657.76 704.11 20.00 224.12

7 350*200*3

Radiator 1426.30 1431.52 20.00 403.00

15Dissipator 1281.50 1360.46 20.00 448.73

Package 20.00 58.30 20.00 71.60

Thermal Strap 1357.05 1404.97 20.00 426.49

8 500*300*2

Radiator 1394.21 1420.11 20.00 417.74

3.75Dissipator 1192.14 1295.43 20.00 372.99

Package 20.00 57.46 20.00 70.85

Thermal Strap 1306.80 1339.83 20.00 389.14

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resultsSr. Dimension Part

Steady State Condition Transient ConditionsDissipation

Min. Temp Max. Temp Min. Temp Max. Temp

9 500*300*2

Radiator 2092.17 2109.45 20.00 515.14

15Dissipator 1861.90 1988.10 20.00 520.01

Package 20 57.46 20.00 70.85

Thermal Strap 2003.82 2037.24 20.00 505.82

10 500*300*3

Radiator 1394.75 1412.03 20.00 374.09

3.75Dissipator 1192.14 1285.43 20.00 339.37

Package 20.00 57.46 20.00 70.85

Thermal Strap 1306.80 1339.82 20.00 353.07

11 500*300*3

Radiator 2092.17 2109.45 20.00 515.14

15Dissipator 1861.90 1988.10 20.00 520.01

Package 20 57.46 20.00 70.85

Thermal Strap 2003.82 2037.24 20.00 505.82

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Conclusions1. For small Heat Dissipation from Instruments, Passive

Radiator cooling can be very effective and economical.

2. Increasing the surface area of the radiator does not increase the heat transfer from the satellite.

3. Increased Surface Area Increased Incident Load Reduced Heat Transfer.

4. Increasing the thickness of the radiator does not increase the heat transfer from the satellite.

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Validation of Results and Conclusions

Spacecraft Thermal Vacuum Test

Infrared Simulation

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references1. Spacecraft Thermal Control Handbook, Vol.1; Fundamental Technologies,

Chapter 1-6, David G. Gilmore, Pages 1-222.2. Thermal Control System of the Moon Mineralogy Mapper Instrument, Josh I

Rodriguez, Jet Propulsion Laboratory, California Institute of Technology.3. “The Moon Mineralogy Mapper (M3) on Chandrayaan-1” by Alok Chatterjee,

Padma Varanasi.4. “The Moon Mineralogy Mapper (M3) for lunar science” by A. Chatterjee,

Padma Varanasi, A.S.K Kumar.5. “Thermal Control System of the Moon Mineralogy Mapper Instrument” by

Jose I. Rodriguez, Jet Propulsion Laboratory, California Institute of Technology.

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Radiator size calculator (Java netbeans 8.0.1)

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Code for radiator

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Thank You.