M. Diaz-AguadoFIELDS iPDR – Thermal Solar Probe Plus FIELDS Instrument PDR Thermal Subsystem Millan F. Diaz-Aguado SSL Berkeley [email protected]

M. Diaz-Aguado 1FIELDS iPDR – Thermal

Solar Probe Plus FIELDSInstrument PDR

Thermal Subsystem

Millan F. Diaz-Aguado

SSL Berkeley

[email protected]

mailto:[email protected]


Overview

• FIELDS Antenna Design– V1-V4– V5

• MEP Thermal Design• MAG Thermal Design• SCM Thermal Design• Mission Phases• Thermal Requirements

– Subsystem temperature requirements– Testing temperature requirements

• Thermal Environment• Thermal Assumptions• Analysis Temperatures• Heater Power by Phase• Peer Review Status - Advisories• Future Work


Antenna Thermal Design

• Niobium C103 for whip and shield

• Sapphire alumina insulators• Molybdenum TZM for

brackets and antenna stub• Radiator on Preamp white

paint (Z93)• Isolated from the SC

(Titanium shim)• Preamp Power 0.28 +/- 15%

W• Preamp Heaters are 2.3 W

(@70% duty cycle, 1.6W)• Monopod, pin-puller MLI

blanketed and isolated from SC

• Whip-fork isolated from SC

Whip/Shield Nb C103

Nb C103 (Moly TZM backup)

Preamp Radiator

Pin Puller

Monopod

Pin Puller


Whip Antenna Thermal Design

• MLI Blanket between the assembly and the SC radiator

• Pin-puller white paint (Z93 C50)– Slew at phase 2 drives the

thermal design• White paint on stub-cage

mount (V3)• GeBk (or STAMET) on

aluminum structure • MLI blanket on flyweight

brake• Preamp operational

temperature is -55°C to 55°C

• Preamp survival temperatures is -55°C to 70°C

High Temperature MLI

MLI

Z93 White Paint


V5 Preamp Antenna Thermal Design

• Ultem isolators from carbon fiber boom

• Aluminum antennas– Clear Alodined

• Antennas thermally isolated from preamp

• MLI blanket on box• Heat load 0.1+/-15% W• Preamp operational

temperature -175°C to 40°C

• Preamp survival temperature -220°C to 60°C

Antennas Isolated from Preamp

MLI Blanket


MEP Thermal Design

• Z307 Conductive Black Paint (high emittance surface required for boxes inside the SC)

• #8 bolts contact box to panel (wet contact) • 8.5W/°C (+/- 15%)• Max power draw 16.5 W (+/-15%)• Operational Temperatures -15°C to 55°C• Survival Temperatures -20°C to 60°C


Thermal Environment

Orbit Location Heat Flux

Maximum solar flux at solar encounter (9.86 Rs)

651 KW/m2

Minimum solar flux at aphelion (1.02 AU)

1314 W/m2

Maximum solar flux during communication slew (0.7 AU)

2790 W/m2

Venus albedo 0.8 ±0.02

Venus IR emission 153 W/m2

Coronal heating at solar encounter (9.86 Rs)

< 3 W/m2


Cases Studied – Mission Phases

Hot MP #

Cold MP#

Mission PhaseInstrument operation

SPP-Sun Distance (AU)

S/C orientation y-axis

1 101 Launch, Aphelion 1 Off 1.02 Varies2 102 Heat radiators 1 & 4 Off 1.02 -903 103 Recharge and cruise Off 1.02 454 104 Launch Error Correction Off 1.02 Varies5 105 Recharge and cruise Off 1.02 456 106 Early cruise and instrument check-out On 1.01 457 107 Heat radiators 2 & 3 Off 0.90 908 108 Cruise, thermal slew Off 0.90 459 109 Cruise, All instrument check out, Fanbeam/SSR playbacks On 0.82 010 110 HGA commission and SSR playbakcs Off 0.75 011 111 Venus warm-up, eclipse and recharge Off 0.72 4512 112 Communication downlink (slew up to 45°) Off 0.70 0-4513 113 Science turn on/off On 0.25 014 114 Science perihelion 1, 34.9 Rs On 0.162 015 115 Science perihelion 2, 27.4 Rs On 0.127 016 116 Science perihelion 3, 19.9 Rs On 0.093 017 117 Science perihelion 4, 15.5 Rs On 0.072 018 118 Science perihelion 5, 12.9 Rs On 0.060 019 119 Sicence perihelion 6, 11.1 Rs On 0.052 020 120 Science perihelion 7, 9.5 Rs On 0.044 021 121 Science with two 4 hr Xband and recharge, 20 Rs On 0.093 0

Deployment


Mission Phases that Drive Thermal Design

• Mission Phase 2– SC maneuvers to warm their radiators– Antennas are not deployed yet– Pin-pullers get warm

• Mission Phase 6– Deployment of antennas– Operation of pin-pullers and hinge parts, including flyweight

break• Mission Phase 20

– SC closest approach to the Sun– Antennas and shield are exposed to 651 KW/m² – Limit heat input to the SC

• Mission Phase 113-120– SC power constraint during operations limits operational heaters


Thermal Assumptions

• V1-V4 Survival Heaters 2.3W heater (70% duty cycle, max 1.6W)

• MAG Heaters (1.4 W, 30% loss, at 70% max 0.65W)• SCM Survival Heaters • Aluminum 6061, Titanium Ti-6Al-4V, Niobium C103,

Molybdenum TZM• MLI e*=.03/.05• Preamp Heat Load (v1-v4) 0.28 W +/-15%• Preamp Heat Load (v5) 0.1 W +/- 15%• MAG Heat Load 0.06 W +/-15%• MEP Heat Load 16.5W +/-15%

BOL EOL α ε α/ε α ε α/ε Black Nickel 0.81 0.26 3.12 0.79 0.24 3.29 Previous testing (MAVEN)Black Paint Z307 0.97 0.89 1.09 0.93 0.85 1.09 Previous testing (MAVEN)

GeBk 0.50 0.81 0.62 0.55 0.78 0.71 Will be changed to new values given to us by APL of STAMET (similar to GeBk)

White Paint Z93 0.13 0.94 0.14 0.45 0.88 0.51 Goddard Previous TestingNiobium C103 0.46 0.40 1.14 0.62 0.30 2.09 Testing PROMES (+/-15%)

Molybdenum TZM 0.33 0.14 2.34 0.33 0.14 2.34 Testing PROMES(conservative values as a/e goes down as temperature increases)

Aluminum Clear Alodine .13 .09 1.44 .23 .08 2.8 Previous Testing (MAVEN)


Thermal Requirements

ColdSurvival

(°C)

Cold Op.(°C)

Hot Op.(°C)

Hot Survival

(°C)

Whip/Shield* -140 35 1305 1305

Preamp V1-V4 -55 -55 55 70

Hinge -75 -70 70 170

Pin-Pullers Pre-Actuation -55 -55 60 60

Post-Actuation -120 - - 100

MEP** -20 -15 55 60

Preamp V5 -220 -180 40 65

*Temperature predicts with α/ε from PROMES testing**Box inside the SC, thermally conductively coupled to surface


Design and Test Temperature Requirements (Instruments Outside SC)

+/-10°C* is the analytical & design margin that is to be defined by each instrument

*5°C temperature difference is the APL standard for actively temperature controlled instruments

**Antenna and Shield are excepted, with a +100°C hot margin instead of +10°C, EDTRD_0193. This margin is added to the predicted temperatures.

Non-operational survival test limit

Non-operational survival predict Operational

predict

Non-operation

al survival

test limit

Non-operational

survival predictOperational

predict

Required science operational limits

(if applicable)

10°C* (TBR)

+

10°C (TBR)+

10°C* (TBR)

+

10°C** (TBR)+

Operational test, flight allowable

Operational test, flight allowable


Design and Test Temperature Requirements (Boxes Inside SC)

Non-operational survival test limit

5°C

Operational Testing &Flight allowable limit

10°CAnalytical &

design margin

Operational prediction

Non-operation

al survival

test limit

5°C

Operational Testing &

Flight allowable

limit

10°CAnalytical &

design margin

Operational prediction

Maximum expected T-range

Maximum expected T-range

-30°C -25°C -15°C 55°C 65°C 70°C

MEP


Heat Flux Thermal Requirement

• Limit of heat flux from FIELDS to SCSC FIELDS Comments

SC Bus 6 W Conductive from monopod to SC Bus and whip fork

TSA 25 W Conductive from antenna base shim to TSA

CSPR 253 W Radiation from Antenna to CSPR

SC


Test Thermal Requirements

ColdSurvival

(°C)

Cold Op. (°C)

Hot Op. (°C)

Hot Survival

(°C)

Whip/Shield -150 25 1405 1405

Preamp V1-V4* -60 -60 65 80

Hinge -140 -70 45 215

Pin-Pullers Pre-Open -130 -80 50 70

Post-Open -130 - - 115

MEP -30 -25 65 70

Preamp V5 -230 -190 40 75

*Survival and Operational Heater Controlled


Predict Temperatures

ColdSurvival

(°C)

Cold Op. (°C)

Hot Op. (°C)

Hot Survival

(°C)

Whip/Shield -135.6 38.7 1302 1302

Preamp V1-V4* -52.5 -52.5* 49.4 65.6

Hinge -127.0 -59.0 30.6 208

Pin-Pullers Pre-Open -118.3 -68.6 35.4 62.4

Post-Open -77.2 - - 104.8

MEP -30 -17.2 75.6 70

Preamp V5 -216.7 -177.5 4.3 60.2

* Op. cases cold temperature (phases 106,109). Cold science (Phases 113-121). is -50.3 °C, heater setpoint is -55 °C


Heater Power

• Survival and Operational Heater Power– V1-V4 (set-point -55°C)

Phase: MP101 MP10

2MP103

MP104

MP105

MP106

MP107

MP108

MP109

MP110

MP111

MP112

MP113

MP114

MP115

MP116

MP117 MP118 MP119 MP120 MP12

1

Operational: Off Off Off Off Off On Off Off On Off Off Off On On On On On On On On OnDistance from

Sun (AU) 1.02 1.02 1.02 1.02 1.02 1.01 0.90 0.90 0.82 0.75 0.72 0.70 0.25 0.162 0.127 0.093 0.072 0.060 0.052 0.044 0.093

Node/Units W W W W W W W W W W W W W W W W W W W W WPreamp_V1 0.16 0.19 0.22 1.4 0 0 0 0 0.34 0.47 0 0.59 0 0 0 0 0 0 0 0 0Preamp_V2 0.32 0 0.96 0.76 0.75 0.58 0 0.75 0.39 0.52 0.92 0.65 0 0 0 0 0 0 0 0 0Preamp_V3 0.17 1.3 0 1.6 0 0 0 0 0.41 0.53 0 0.61 0 0 0 0 0 0 0 0 0Preamp_V4 0.35 0 0.86 0.72 0.66 0.49 0 0.67 0.41 0.53 0.94 0.62 0 0 0 0 0 0 0 0 0

Worst Case Hot Survival

Worst Case Hot Operational Pre-Science Phases


Heat Flux

• Heat Flux from instrument to SC (W) for Phase 20– Negative heat flux means from SC to instrument– Requirements:

• Instrument to TSA 25 W• Instrument to CSPR 253 W• Instrument to SC Bus 6 W

BUS TSA SC_CSPR

FIELDS_Antenna 0 1.3 53 Radiation

FIELDS_SHLD 0 0 121 Radiation

FIELDS_STUB 0 0 19 Radiation

FIELDS_HINGE 0 0 1 Radiation

FIELDS_MECH 0 0 0 Conduction to TSA, Radiation

FIELDS_PREAMP 0 0 1 Radiation

FIELDS_Monopod -0.4 0 0 Conduction

TOTAL -0.4 1.3 195


Peer Review Thermal Advisories

# Originator Advisory13 General Check thermal isolator at Hinge Mount interface.14 General Thermal treatments are needed for all surfaces.17 Stu Harris Check Thermal input to the preamp due to harness.19 Chris Smith Check deploy cases for Hinge and Release temps.20 Chris Smith Check thermal shield sizing.21 Chris Smith Determine coatings for back of shields.

# Answer

13 The Interface between the TSA and the Hinge is titanium

14 All surfaces are treated thermally

17 Modeled coax cable, preamp is not affected by the heat leak

19 All cases are checked, including deploy cases

20 Thermal shield sizing has been checked

21 The coatings for back of the Hinge shield is alodined

No RFA’s were received, six thermal advisories were received and answered


Back Up Slides


Future Work

Board Analysis

Voltage Regulators

Basic rule of thumb:• 2oz. Copper layer

per Watt

board

Junction

Case

Rpin Rbond

Q case

Θjc

Junction Temperature, Tjunction = Tboard + Q*Rtotal

Total Resistance, Rtotal = Θjc + 1/(1/Rbond + 1/Rpin)

Part QTY Total Peak

Power(W)

TotalNominalPower

(W)

PeakPower

Per Part(W)

NominalPower

Per Part(W)

Junction to CaseThermal

Resistance(°C/W)

# Of Pins

Bonded(CV-2943)

Junction/Case ComponentTemperature (°C)

at Peak Power

ComponentTemperature (°C)

at Nom Power

OP400 1 0.55 0.36 0.55 0.36 10 14 No Junction 55 51RNC65, RES (300) 1 0.4 0.325 0.4 0.325 2 Yes Case 46 46OP200 1 0.3 0.205 0.3 0.205 16 8 No Junction 54 51

outinout vviQ


EDTRD Thermal Requirements

EDTRD # Requirement Description

EDTRD_0182 Instruments mounted internally to the SC bus shall meet the thermal design requirements

EDTRD_0183, (same as 0057)

Instruments shall be isolated from SC shall provide at least 40 °C/W

EDTRD_0185 Instruments brackets shall be blanketed

EDTRD_0186 Instruments shall be designed and tested to the thermal interfaces listed in Table 5-2 (-25°C to 65°C Operational, -30°C to 70°C Survival)

EDTRD_0187 Cold turn on and warm-up sequence shall be identified and defined for each instrument (TBR)

EDTRD_0188 Instruments shall be designed to operate within specifications for the science phase of the mission and not suffer permanent degradation during any other phase of the mission




EDTRD_0056 Component designs that are thermally coupled to the spacecraft shall have TBD between the component baseplate and spacecraft mounting surface where needed for the thermal load

EDTRD_0057 Instruments shall be isolated from SC shall provide at least 40 °C/W

EDTRD_0058 Components that are located internal to the spacecraft bus shall have a surface emissivity of 0.85 or greater

EDTRD_0065 All spacecraft components shall be designed to operate within specifications for all phases of the mission

EDTRD_0189 Instruments shall complete a successful thermal vacuum flight qualification testing program prior to delivery to the SC




EDTRD_0190 Testing program shall consist of thermal vacuum balance and thermal vacuum cycle

EDTRD_0191 All instruments thermal test plans shall be provided to the SC thermal engineer for review and approval

EDTRD_0192 Flight predictions shall demonstrate at least 10°C of margin within the instrument operational or survival test temperatures with the exception for active heater control (5°C is acceptable)

EDTRD_0193 Flight predictions for atypical instruments, SWEAP-SPC and FIELDS PWI, shall demonstrate at least a 10°C margin on the cold side and at least 100°C margin on the hot side for minimum and maximum temperatures

EDTRD_0194 Instrument level thermal vacuum balance test shall be performed for thermally isolated instruments

EDTRD_0195 The thermal hardware for these instruments forgoing the thermal balance test shall demonstrate in thermal cycling that all thermal hardware works as expected




EDTRD_0196 The test shall simulate SC conductive and radiative interface temperatures, space radiation couplings, and environmental heat inputs

EDTRD_0197 Thermal balance spacecraft simulated temperatures are in Table 5‑2. Instrument component limits defined in the instrument test specification shall have a 10°C margin for testing, as illustrated in slides 4-5 (-25°C to 65°C Operational, -30°C to 70°C Survival)

EDTRD_0198 The instrument thermal control system shall demonstrate the ability to maintain temperatures within survival limits while in non-operating mode and within operational limits while in operating mode

EDTRD_0199 Instruments shall demonstrate via testing proper function of survival and operational heaters

EDTRD_0200 The test shall measure the isolation scheme resistance, which includes the bracket, bolts, grounding straps, and harness cables, between the instrument and the SC




EDTRD_0201 The test shall collect sufficient data to correlate the instrument thermal model to allow untested conditions to be analyzed.

EDTRD_0203 The instrument thermal model shall be correlated to the balance test at both the maximum hot and minimum cold cases

EDTRD_0204 Instrument thermal model correlation results shall be within 3°C of the thermal balance test data

EDTRD_0205 Instruments shall provide a thermal balance test report with correlated model data to the SPP Thermal Engineer

EDTRD_0206 Cold case balance dwell condition shall be long enough to verify the duty cycle of the survival and operational heaters

EDTRD_0207 This should decrease transition time between cycles, thus total test time. Instrument component temperatures shall be based on flight model predictions if the isolation coupling is not flight-like




EDTRD_0208 Instrument component temperatures shall be tested to 10°C beyond flight model predictions

EDTRD_0209 Flight model testing shall complete six operational and one survival cycle

EDTRD_0210 Engineering Model (EM) testing shall appropriately represent the cycles for each component, and will be approved on a case by case basis by the SPP Thermal Engineer

EDTRD_0211 The TV test shall include six powered operational cycles and one survival cycle

EDTRD_0212 CPT’s shall be conducted during instrument level TV testing

EDTRD_0213 Minimal functional tests shall be performed at all remaining plateaus if no CPT performed


Cold Temperatures

Sheet:

MP101 MP102 MP103 MP104 MP105 MP106 MP107 MP108 MP109 MP110 MP111 MP112 MP113 MP114 MP115 MP116 MP117 MP118 MP119 MP120 MP121

Operational Off Off Off Off Off On Off Off On Off Off Off On On On On On On On On On

Distance from Sun (AU)

1.02 1.02 1.02 1.02 1.02 1.01 0.90 0.90 0.82 0.75 0.72 0.70 0.25 0.162 0.127 0.093 0.072 0.060 0.052 0.044 0.093

Node/Units [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C]

FIELDS_Whip1 5.1 -76.7 29.2 -135.6 33.9 42.9 46.0 56.2 90.4 104.6 103.6 105.2 388.4 546.7 652.5 815.2 957.3 1077.9 1182.3 1299.3 809.4FIELDS_Whip2 3.2 101.8 -37.3 -35.2 -37.0 45.1 50.4 58.7 92.0 105.5 105.9 105.2 390.1 548.4 652.9 813.1 960.0 1079.2 1181.8 1301.5 812.1FIELDS_Whip3 -26.4 107.9 -29.2 -28.6 -28.9 38.7 28.2 52.8 91.3 105.7 98.9 105.0 388.4 548.6 654.9 813.7 959.3 1072.3 1185.1 1301.6 811.9FIELDS_Whip4 3.4 -35.0 40.0 -129.3 39.7 48.4 60.5 62.5 91.2 105.6 110.2 105.3 388.3 549.0 654.7 814.5 957.3 1076.0 1180.7 1298.9 811.5

FIELDS_Preamp1 -52.5 -52.7 -50.3 -52.7 -44.4 -46.8 -0.1 -38.4 -52.6 -52.6 -26.0 -52.6 -42.5 -37.7 -35.3 -27.7 -21.7 -16.3 -10.7 1.6 -26.5FIELDS_Preamp2 -52.6 -14.0 -52.7 -52.7 -52.7 -52.7 -32.4 -52.7 -52.7 -52.7 -52.8 -52.7 -50.3 -42.8 -39.7 -31.0 -24.3 -19.3 -11.7 2.3 -33.2FIELDS_Preamp3 -52.6 3.6 -52.7 -52.7 -52.7 -52.7 -53.8 -52.7 -52.7 -52.7 -52.8 -52.7 -42.9 -36.7 -34.2 -29.5 -22.5 -16.5 -11.5 0.3 -29.3FIELDS_Preamp4 -52.8 -44.7 -53.2 -53.2 -53.1 -53.2 -18.8 -53.2 -53.1 -53.1 -53.2 -53.2 -49.2 -42.0 -38.8 -32.1 -23.8 -19.6 -12.4 2.0 -31.4FIELDS_Hinge1 -10.2 -34.1 6.9 -125.8 8.0 -7.2 38.5 10.7 -29.0 -20.6 36.3 -25.5 21.4 46.0 60.7 88.6 113.1 134.2 152.5 177.2 89.4FIELDS_Hinge2 -10.6 42.0 -64.9 -67.6 -63.3 -49.7 -14.0 -42.9 -30.5 -22.6 -38.1 -27.4 20.0 45.2 61.6 89.5 113.4 135.9 152.0 177.3 89.3FIELDS_Hinge3 -13.0 46.4 -61.0 -62.1 -59.0 -53.5 26.0 -46.4 -28.4 -21.2 -43.7 -25.8 20.6 47.1 62.1 91.8 112.8 134.7 152.3 176.8 89.5FIELDS_Hinge4 -12.7 -67.7 6.0 -127.0 6.9 7.8 41.9 25.3 -32.6 -24.5 56.6 -29.0 16.5 44.2 61.5 86.8 113.8 134.4 151.8 177.3 88.3FIELDS_Shield1 -7.9 -105.5 33.8 -129.0 34.4 34.4 62.3 50.1 58.1 72.1 92.8 70.8 333.4 484.9 585.0 737.0 872.2 984.6 1083.7 1194.5 733.5FIELDS_Shield2 -7.7 90.4 -54.3 -52.4 -53.3 -6.7 63.3 5.2 59.5 73.6 42.8 71.7 333.9 485.7 585.4 737.4 873.2 984.4 1084.1 1195.1 734.1FIELDS_Shield3 -8.7 93.1 -48.0 -45.8 -46.9 -28.7 43.2 -18.6 58.8 72.6 10.5 70.7 333.7 485.5 585.5 737.3 873.5 984.9 1084.1 1195.7 734.8FIELDS_Shield4 -8.1 9.0 36.1 -122.1 36.5 42.7 71.7 58.1 58.5 72.3 102.2 70.7 333.1 484.7 584.5 736.3 872.0 983.4 1082.2 1193.8 733.4

FIELDS_Pinpuller1 -35.7 -101.1 -9.6 -118.3 -4.5 -12.9 48.6 17.0 -50.8 -42.4 34.7 -45.6 -0.6 4.6 7.0 18.0 19.2 20.7 20.3 30.5 14.9FIELDS_Pinpuller2 -57.9 25.3 -76.7 -68.7 -66.6 -68.4 -17.2 -66.1 -63.4 -58.3 -77.2 -63.5 -38.2 -28.7 -26.6 -14.6 -13.0 -7.0 -2.1 12.3 -18.6FIELDS_Pinpuller3 -60.6 30.7 -68.5 -61.3 -59.3 -61.9 -33.3 -59.0 -61.1 -54.6 -75.4 -58.4 -24.5 -18.0 -14.9 -9.0 -5.8 -1.6 3.2 14.8 -12.0FIELDS_Pinpuller4 -36.4 -31.5 -22.9 -111.5 -16.6 -17.6 37.1 10.2 -51.9 -44.4 28.3 -48.9 -13.0 -6.4 -0.4 2.1 11.5 11.6 21.2 32.5 6.0

MEP -30.0 -30.0 -30.0 -30.0 -30.0 -17.2 -30.0 -30.0 -17.2 -30.0 -30.0 -30.0 -17.2 -17.2 -17.2 -17.2 -17.2 -17.2 -17.2 -17.2 -17.2

Cold temperatures


Hot Temperatures

Sheet: MP1 MP2 MP3 MP4 MP5 MP6 MP7 MP8 MP9 MP10 MP11 MP12 MP13 MP14 MP15 MP16 MP17 MP18 MP19 MP20 MP21Operational Off Off Off Off Off On Off Off On Off Off Off On On On On On On On On On

Distance from Sun (AU)

1.02 1.02 1.02 1.02 1.02 1.01 0.90 0.90 0.82 0.75 0.72 0.70 0.25 0.162 0.127 0.093 0.072 0.060 0.052 0.044 0.093

Node/Units [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C]FIELDS_Whip1 -100.5 -54.3 53.9 89.6 54.5 81.7 68.8 106.6 120.0 159.7 132.8 139.2 439.0 611.9 724.5 898.0 1054.5 1181.0 1294.8 1421.8 893.5FIELDS_Whip2 86.0 132.1 -4.6 32.1 -4.6 85.3 75.8 111.3 120.4 159.1 136.8 142.5 440.7 610.6 724.7 900.1 1054.1 1183.4 1297.2 1422.6 895.0FIELDS_Whip3 92.5 141.7 9.9 27.4 10.4 79.4 50.7 103.6 120.5 159.7 129.6 135.3 438.7 610.5 724.5 898.4 1055.6 1181.3 1298.1 1425.4 895.6FIELDS_Whip4 -88.4 -11.8 64.1 92.1 64.1 88.0 86.4 114.0 120.8 159.2 140.2 145.9 439.8 611.6 725.6 897.5 1053.8 1183.4 1293.4 1422.1 892.0

FIELDS_Preamp1 -64.8 -42.0 2.9 40.9 2.8 5.7 65.9 30.8 -3.8 4.9 46.6 48.4 7.3 11.9 15.4 20.6 23.3 28.2 32.9 46.3 20.3FIELDS_Preamp2 -15.2 21.1 -31.5 -2.9 -31.5 -25.6 6.2 -13.8 -4.1 3.4 -3.2 -3.4 1.9 10.1 12.7 16.8 28.5 30.6 34.3 46.6 21.0FIELDS_Preamp3 26.5 63.2 -29.5 -19.6 -29.5 -22.8 -9.3 -13.1 -6.4 2.4 -2.5 -1.2 4.5 9.2 12.5 17.0 22.8 29.0 33.9 45.6 18.6FIELDS_Preamp4 -48.8 -3.1 -19.9 -8.1 -19.8 -16.4 35.2 1.7 -3.2 4.1 13.1 12.8 3.0 10.3 12.4 17.8 25.8 29.1 34.0 46.6 21.4FIELDS_Hinge1 -105.4 -12.4 30.2 36.7 30.1 24.6 58.3 50.9 3.7 26.5 74.4 77.6 47.7 77.6 95.0 121.7 149.9 166.9 186.5 212.7 121.1FIELDS_Hinge2 32.2 60.3 -33.9 -20.1 -33.6 -21.9 4.7 -14.9 1.1 22.2 5.9 8.1 46.3 74.3 92.2 120.5 146.6 166.6 186.1 211.6 120.8FIELDS_Hinge3 34.8 66.8 -30.1 14.6 -30.2 -22.4 42.9 -15.6 3.6 25.6 6.0 8.0 48.9 75.6 95.9 121.2 145.7 167.2 186.4 213.0 124.9FIELDS_Hinge4 -90.3 -48.5 28.2 31.8 28.3 38.8 62.2 65.6 1.4 22.4 90.1 93.2 46.4 74.2 92.0 120.1 147.3 167.2 185.1 212.0 119.0FIELDS_Shield1 -108.4 -78.8 57.7 80.8 57.3 73.6 88.1 98.7 88.8 124.9 127.8 132.2 378.8 541.7 649.2 811.1 957.1 1077.0 1183.6 1302.6 808.4FIELDS_Shield2 78.5 119.2 -20.9 57.3 -20.8 32.1 89.5 51.5 89.7 125.0 81.8 86.1 379.5 542.2 649.2 811.8 957.0 1077.5 1183.4 1302.9 808.7FIELDS_Shield3 73.2 121.7 -14.4 -11.5 -14.5 10.6 69.9 24.7 89.4 125.1 54.2 58.0 380.0 542.0 649.2 812.0 957.7 1076.8 1183.8 1303.5 809.1FIELDS_Shield4 -54.4 32.5 61.9 85.3 61.6 83.0 99.0 107.6 89.6 124.7 136.9 141.8 379.5 541.8 649.2 810.3 956.9 1076.3 1182.5 1302.1 808.5

FIELDS_Pinpuller1 -58.4 -36.7 32.0 31.5 31.8 34.8 84.2 76.3 18.1 50.5 101.5 104.6 49.2 51.8 55.1 61.9 63.3 65.1 69.6 79.3 60.3FIELDS_Pinpuller2 12.9 61.8 -11.0 23.4 -11.2 -11.0 31.0 7.1 7.9 27.3 21.3 21.9 22.5 30.1 33.7 39.7 53.0 51.1 56.6 71.1 40.6FIELDS_Pinpuller3 24.2 64.5 -5.5 4.1 -5.4 -3.7 17.4 11.4 8.9 32.4 26.6 28.3 29.2 33.4 36.4 40.2 51.0 51.7 60.3 69.0 41.5FIELDS_Pinpuller4 -57.2 12.6 22.1 11.5 21.7 30.3 72.5 69.7 18.4 46.2 94.0 95.1 42.5 48.2 52.0 60.2 63.3 67.3 74.7 90.0 56.1

MEP 70.0 70.0 70.0 70.0 70.0 75.6 70.0 70.0 75.6 70.0 70.0 70.0 75.6 75.6 75.6 75.6 75.6 75.6 75.6 75.6 75.6

Hot temperatures with heater off


Heaters

Instrument Temperature Set Point (°C) Heater Resistance Control TypeON OFF

FIELDS, FGM 1 -25 -20 350 Ω (TBR) Elec HWFIELDS, SCM -50 -45 1041 Ω (TBR) Elec HWFIELDS, PWI 1 -55 -50 362 Ω (TBR) ThermostatFIELDS, PWI 2 -55 -50 362 Ω (TBR) Thermostat


FIELDS, FGM 2 -25 -20 350 Ω (TBR) Elec HWFIELDS, e-sensor (stub) Elec HWFIELDS, PWI 3 -55 -50 362 Ω (TBR) ThermostatFIELDS PWI 4 -55 -50 362 Ω (TBR) Thermostat


FIELDS 1 PWI Mechanisms

-65 -60 2535Ω (TBR) Thermostat

FIELDS 2 PWI Mechanisms

-65 -60 2535Ω (TBR) Thermostat

FIELDS Survival Heater Set Points, Resistance, and Control Type

FIELDS Operational Heater Set Points, Resistance, and Control Type

FIELDS Pin-pullers Deployment Heater Set Points, Resistance, and Control Type


SC Thermal Model

• FIELDS Antennas Deployed


MAGS Temps and Heater Power

Phase: 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121

Node/Units [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W] [W]

MAGIB.2 0.7 0.7 0.0 0.7 0.0 0.7 0.7 0.7 0.7 0.7 0.0 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7

MAGOB.2 0.7 0.7 0.7 0.7 0.7 0.7 0.0 0.0 0.7 0.7 0.0 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7

Phase:

Cold101

Cold102

Cold103

Cold104

Cold105

Cold106

Cold107

Cold108

Cold109

Cold110

Cold111

Cold112

Cold113

Cold114

Cold115

Cold116

Cold117

Cold118

Cold119

Cold120

Cold121


MAGOB.2 -33.7 -47.7 34.7 -49.2 34.1 4.8 4.8 -9.9 -54.4 -54.4 29.9 -54.5 -54.5 -54.4 -54.4 -54.4 -54.4 -54.4 -54.4 -54.3 -54.4

MAGIB.2 9.1 21.1 23.6 -52.0 23.6 24.0 24.0 23.8 -50.6 -50.7 18.3 -50.8 -50.7 -50.5 -50.6 -50.8 -50.5 -50.7 -50.5 -50.3 -50.3

Phase: mp1 mp2 mp3 mp4 mp5 mp6 mp7 mp8 mp9 mp10 mp11 mp12 mp13 mp14 mp15 mp16 mp17 mp18 mp19 mp20 mp21


MAGOB.2 -13.4 -6.6 19.2 39.8 19.4 1.6 16.4 22.6 -54.2 -54.2 42.9 47.3 -54.2 -54.2 -54.2 -54.1 -54.1 -54.1 -54.0 -53.9 -54.1

MAGIB.2 -44.4 -44.2 44.6 64.6 43.7 -6.2 2.7 12.6 -48.4 -48.3 34.2 38.4 -48.5 -48.3 -48.4 -48.6 -48.3 -48.5 -48.2 -48.2 -48.2

Hot Temperatures

Cold Temperatures

Heater Power (not including inefficiencies), setpoint at -25ºC


MAG Model

• M. Choi (NASA Goddard) model integrated in SC model


Preamp V5 Temperatures

Phase: MP1 MP2 MP3 MP4 MP5 MP6 MP7 MP8 MP9 MP10 MP11 MP12 MP13 MP14 MP15 MP16 MP17 MP18 MP19 MP20 MP21

Operational Off Off Off Off Off On Off Off On Off Off Off On On On On On On On On OnDistance from Sun

(AU) 1.02 1.02 1.02 1.02 1.02 1.01 0.90 0.90 0.82 0.75 0.72 0.70 0.25 0.162 0.127 0.093 0.072 0.060 0.052 0.044 0.093

Node/Units [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C]IS_FIELDS_PREAMP.

30 -157.3 -154.6 49.0 60.2 50.7 4.3 8.7 14.6 -169.3 -211.1 33.2 37.6 -169.3 -169.2 -169.2 -169.4 -169.2 -169.3 -169.2 -169.1 -169.1

Hot Cases

Phase :

MP101 MP102 MP103 MP104 MP105 MP106 MP107 MP108 MP109 MP110 MP111 MP112 MP113 MP114 MP115 MP116 MP117 MP118 MP119 MP120 MP121

Operational Off Off Off Off Off On Off Off On Off Off Off On On On On On On On On OnDistance from Sun (AU) 1.02 1.02 1.02 1.02 1.02 1.01 0.90 0.90 0.82 0.75 0.72 0.70 0.25 0.162 0.127 0.093 0.072 0.060 0.052 0.044 0.093

Node/Units [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C] [°C]IS_FIELDS_PREAMP.

30 -174.4 -169.1 43.2 -179.5 44.0 -9.0 5.7 -6.6 -177.3 -216.7 29.6 -217.0 -177.4 -177.2 -177.3 -177.5 -177.2 -177.4 -177.2 -176.9 -176.9

Cold Cases

Cold Survival Case

Hot Survival Case


Thermal Margins

• Temperature difference (ΔT) between predicts and testing temperatures

(°C)Cold

SurvivalCold Op. Hot Op. Hot

Survival

Whip Antenna/Shield >10 >10 >100 >100

Preamp V1-V4* 5 >10 >10 >10

Hinge >10 >10 >10 >10

Pin-Pullers Pre-Open >10 >10 >10 >10

Post-Open >10 >10 >10 >10

MEP 10 10 10 10

Preamp V5 >10 >10 >10 >10

*Survival Heater Controlled**Survival and Operational Heater Controlled


SCM Thermal Design

• MLI Blanket covering the SCM• Heat Source 0.325W (+/-15%)• Isolated from boom (peek bedplate)• Harness wrapped inside MLI


MAGs Thermal Design

• MLI blanket covering the entire MAG• Ti-6Al-4V Kinematic mounts with SiN spheres to isolate from

boom• Shielded twisted pair (STP) 26 AWG wires for heaters (to

reduce heat leak)• G10 Spacers to isolate mounting plate from boom• Power Draw: 0.06W +/-15% (each)• Heater Power 1.4 W, 30% loss due to inefficiency

Kinematic Mounts with SiN Spheres

Documents

M. Diaz-AguadoFIELDS iPDR – Thermal Solar Probe Plus FIELDS Instrument PDR Thermal Subsystem Millan F. Diaz-Aguado SSL Berkeley [email protected]