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Space Engineering - Thermal design handbook - Part 12: Louvers

Thermal louvers are thermal control surfaces whose radiation characteristics can be varied in order to
maintain the correct operating temperature of a component subject to cyclical changes in the amount
of heat that it absorbs or generates.
The design and construction of louvers for space systems are described in this Part 12 and a clause is
also dedicated to providing details on existing systems.
The Thermal design handbook is published in 16 Parts
TR 17603-31-01 Part 1 Thermal design handbook – Part 1: View factors
TR 17603-31-01 Part 2 Thermal design handbook – Part 2: Holes, Grooves and Cavities
TR 17603-31-01 Part 3 Thermal design handbook – Part 3: Spacecraft Surface Temperature
TR 17603-31-01 Part 4 Thermal design handbook – Part 4: Conductive Heat Transfer
TR 17603-31-01 Part 5 Thermal design handbook – Part 5: Structural Materials: Metallic and
Composite
TR 17603-31-01 Part 6 Thermal design handbook – Part 6: Thermal Control Surfaces
TR 17603-31-01 Part 7 Thermal design handbook – Part 7: Insulations
TR 17603-31-01 Part 8 Thermal design handbook – Part 8: Heat Pipes
TR 17603-31-01 Part 9 Thermal design handbook – Part 9: Radiators
TR 17603-31-01 Part 10 Thermal design handbook – Part 10: Phase – Change Capacitors
TR 17603-31-01 Part 11 Thermal design handbook – Part 11: Electrical Heating
TR 17603-31-01 Part 12 Thermal design handbook – Part 12: Louvers
TR 17603-31-01 Part 13 Thermal design handbook – Part 13: Fluid Loops
TR 17603-31-01 Part 14 Thermal design handbook – Part 14: Cryogenic Cooling
TR 17603-31-01 Part 15 Thermal design handbook – Part 15: Existing Satellites
TR 17603-31-01 Part 16 Thermal design handbook – Part 16: Thermal Protection System

Raumfahrttechnik - Handbuch für thermisches Design - Teil 12: Luftschlitze

Ingénierie spatiale - Manuel de conception thermique - Partie 12: Persiennes

Vesoljska tehnika - Priročnik o toplotni zasnovi - 12. del: Žaluzije

General Information

Status

Published

Public Enquiry End Date

26-May-2021

Publication Date

23-Aug-2021

ICS

49.140 - Space systems and operations

Technical Committee

I13 - Imaginarni 13

Current Stage

6060 - National Implementation/Publication (Adopted Project)

Start Date

19-Aug-2021

Due Date

24-Oct-2021

Completion Date

24-Aug-2021

Mandate

M/496 - Mandate addressed to CEN, CENELEC and ETSI to develop standardisation regarding space industry (Phase 3 of the process)

Ref Project

CEN/CLC/TR 17603-31-12:2021 - Space Engineering - Thermal design handbook - Part 12: Louvers

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SLOVENSKI STANDARD
SIST-TP CEN/CLC/TR 17603-31-12:2021
01-oktober-2021
Vesoljska tehnika - Priročnik o toplotni zasnovi - 12. del: Žaluzije
Space Engineering - Thermal design handbook - Part 12: Louvers
Raumfahrttechnik - Handbuch für thermisches Design - Teil 12: Luftschlitze
Ingénierie spatiale - Manuel de conception thermique - Partie 12: Persiennes
Ta slovenski standard je istoveten z: CEN/CLC/TR 17603-31-12:2021
ICS:
49.140 Vesoljski sistemi in operacije Space systems and
operations
SIST-TP CEN/CLC/TR 17603-31-12:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TP CEN/CLC/TR 17603-31-12:2021
TECHNICAL REPORT
CEN/CLC/TR 17603-31-
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
August 2021
ICS 49.140
English version
Space Engineering - Thermal design handbook - Part 12:
Louvers

Ingénierie spatiale - Manuel de conception thermique - Raumfahrttechnik - Handbuch für thermisches Design -

Partie 12 : Persiennes Teil 12: Blenden

This Technical Report was approved by CEN on 28 June 2021. It has been drawn up by the Technical Committee CEN/CLC/JTC 5.

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium,

Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,

Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia,

Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
CEN-CENELEC Management Centre:
Rue de la Science 23, B-1040 Brussels

reserved worldwide for CEN national Members and for
CENELEC Members.
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Table of contents

European Foreword ................................................................................................... 7

1 Scope ....................................................................................................................... 8

2 References .............................................................................................................. 9

3 Terms, definitions and symbols .......................................................................... 10

3.1 Terms and definitions ............................................................................................. 10

3.2 Symbols .................................................................................................................. 10

4 General introduction ............................................................................................ 15

5 Components of a louver ....................................................................................... 16

5.1 Blades .................................................................................................................... 16

5.2 Actuators ................................................................................................................ 18

5.2.1 Bimetals .................................................................................................... 18

5.2.2 Bellows ..................................................................................................... 24

5.2.3 Bourdons .................................................................................................. 35

5.3 Sensors .................................................................................................................. 37

5.3.1 Sensor location ......................................................................................... 37

5.3.2 Coupling options ....................................................................................... 38

5.4 Structural elements ................................................................................................. 38

5.4.1 Actuator housing ....................................................................................... 38

5.4.2 Frames ...................................................................................................... 38

6 Ideal louvers .......................................................................................................... 40

6.1 Sun-light operation.................................................................................................. 40

6.1.1 Introduction ............................................................................................... 40

6.1.2 Heat rejection capability ............................................................................ 40

6.1.3 Effective absorptance ................................................................................ 43

6.1.4 Effective emittance .................................................................................... 46

6.2 Shadow operation ................................................................................................... 52

6.2.1 Introduction ............................................................................................... 52

6.2.2 Radiosity and temperature field of the blades............................................ 53

6.2.3 Heat transfer through the louver ................................................................ 55

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7 Existing systems .................................................................................................. 66

7.1 Summary table ....................................................................................................... 66

7.2 Ats louvers .............................................................................................................. 76

7.2.1 Introduction ............................................................................................... 76

7.2.2 Analytical calculations ............................................................................... 76

7.2.3 Tests ......................................................................................................... 80

7.3 Nimbus louvers ....................................................................................................... 83

7.3.1 Introduction ............................................................................................... 83

7.3.2 Louvers of the sensory subsystem ............................................................ 83

7.3.3 Louver of the control subsystem ................................................................ 84

7.3.4 Flight performance .................................................................................... 86

7.4 Snias louvers .......................................................................................................... 87

7.4.1 Introduction ............................................................................................... 87

7.4.2 Analytical calculations ............................................................................... 88

7.4.3 Tests ......................................................................................................... 95

7.4.4 The Bourdon tube used as an actuator in the SNIAS Louver system ........ 98

Bibliography ........................................................................................................... 104

Figures

Figure 5-1: Relative linear thermal expansion vs. temperature in the case of Invar. T =

273 K. From THE MOND NICKEL CO [35]. ........................................................ 19

Figure 5-2: Relative linear thermal expansion vs. temperature in the case of brasses. T

= 273 K. After Baldwin (1961) [3]. ....................................................................... 20

Figure 5-3: Relative linear thermal expansion vs. temperature in the case of austenitic

steels. T = 273 K. After Zapffe (1961) [39]. ....................................................... 20

Figure 5-4: Relative linear thermal expansion vs. temperature in the case of Nimonic

alloys. T = 273 K. After WIGGIN & Co. (1967) [38]............................................ 21

Figure 5-5: Relative linear thermal expansion vs. temperature for different alloys. T =

273 K. After Baldwin (1961) [3], Zapffe (1961) [39], WIGGIN Co. (1967)

[38]. .................................................................................................................... 21

Figure 5-6: Difference of temperature, ∆T, vs. angle of rotation of the free end, θ, for

several values of the sensitivity, X. After Martin & Yarworth (1961) [21],

KAMMERER (1971) [16]. ................................................................................... 22

Figure 5-7: Sensitivity vs. ratio L/t, for different values of K . After Martin & Yarworth

(1961) [21], KAMMERER (1971) [16]. ................................................................ 23

Figure 5-8: Dimensionless ratio M/K F ∆TL vs. L/t, for several values of w/t. After

c c

Martin & Yarworth (1961) [21], KAMMERER (1971) [16]. ................................... 24

Figure 5-9: Values of α and β vs. ratio a/b for different cross sections of the Bourdon

tube. After Trylinski (1971) [37]. ......................................................................... 36

Figure 5-10: Ratio F/F vs. Bourdon initial coiling angle, ψ . Calculated by the compiler. ...... 37

0 0
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Figure 6-1: Geometry of the blade-baseplate system ........................................................... 40

Figure 6-2: Heat rejection capability, q, vs. blade angle, θ, for several values of the sun

angle, φ. From FAIRCHILD HILLER (1972) [10]. ................................................ 42

Figure 6-3: Heat rejection capability, q, vs. blade angle, θ, for several values of the sun

angle, φ. From Parmer & Stipandic (1968) [27]. .................................................. 43

Figure 6-4: Effective absorptance, α , vs. blade angle, θ, for several values of the sun

eff

angle, φ. After FAIRCHILD HILLER (1972) [10]. ................................................. 45

Figure 6-5: Effective absorptance, α , vs. blade angle, θ, for several values of the sun

eff

angle, φ. After Parmer & Stipandic (1968) [27]. .................................................. 46

Figure 6-6: Effective emittance, ε , vs. blade angle, θ. After FAIRCHILD HILLER
eff

(1972) [10]. ......................................................................................................... 48

Figure 6-7: Effective emittance, ε , vs. blade angle, θ. After Parmer & Stipandic (1968)

eff

[27]. .................................................................................................................... 49

Figure 6-8: Effective emittance, ε , vs. blade angle, θ, for several values of the

eff
baseplate emittance, ε . ε has been numerically calculated by using the
BP eff
ε = (1−B *)dβ
following expression. ................................................. 50
eff
1− ε

Figure 6-9: Effective emittance, ε , vs. blade angle, θ, for several values of the blades

eff
emittance, ε . ε has been numerically calculated by using the following
B eff

expression. ε = (1−B *)dβ ................................................................ 51

eff
1− ε

Figure 6-10: Effective emittance, ε , vs. blade angle, θ, for several b/L values. ε has

eff eff
been numerically calculated by using the following expression.

ε = (1−B *)dβ ................................................................................... 52

eff
1− ε
BP 0

Figure 6-11: Schematic diagram of a louver for shadow operation. ...................................... 53

Figure 6-12: Schematic diagram of the louver array showing the coordinates and the

significant geometrical characteristics. ............................................................... 54

Figure 6-13: Dimensionless radiosity, B*, of the blades for several values of the blade

angle, θ. From Plamondon (1964) [28]. .............................................................. 55

Figure 6-14: Dimensionless temperature, T*, of the blades for several values of the

blade angle, θ. From Plamondon (1964) [28]. ..................................................... 55

Figure 6-15: Function f(θ) vs. blade angle θ. After Parmer & Buskirk (1967)a [25]. ............... 57

Figure 6-16: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. ε = 0,05, ε = ε = 0.87. Calculated
B BP I

by the compiler. .................................................................................................. 58

Figure 6-17: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. ε = 0,05, ε = ε = 0,87. Calculated
B BP I

by the compiler. .................................................................................................. 59

Figure 6-18: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. ε = 0,05, ε = ε = 0,87. Calculated
B BP I

by the compiler. .................................................................................................. 60

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Figure 6-19: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. ε = 0,05, ε = ε = 0,87. Calculated
B BP I

by the compiler. .................................................................................................. 61

Figure 6-20: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. ε = 0,05, ε = ε = 0,87. Calculated
B BP I

by the compiler. .................................................................................................. 62

Figure 6-21: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. ε = 0,05, ε = ε = 0,87. Calculated
B BP I

by the compiler. .................................................................................................. 63

Figure 6-22: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. εB = 0,05, εBP = εI = 0,87. Calculated

by the compiler. .................................................................................................. 64

Figure 6-23: Net heat transfer through the louver, q, vs. baseplate temperature, T , for

several values of the blade angle, θ. ε = 0,05, ε = ε = 0,87. Calculated
B BP I

by the compiler. .................................................................................................. 65

Figure 7-1: Effective emittance, ε , based on area of the large unit, vs. blade angle, θ,

eff

for ATS spacecraft. From Michalek, Stipandic & Coyle (1972) [24]..................... 78

Figure 7-2: Effective absorptance, α , vs. blade angle, θ, for several values of the sun

eff

angle, φ, for ATS spacecraft. From Michalek, Stipandic & Coyle (1972) [24]. ..... 79

θ, for several values of the sun
Figure 7-3: Heat rejection capability, q, vs. blade angle,

angle, φ, for ATS spacecraft. From Michalek, Stipandic & Coyle (1972) [24]. ..... 80

Figure 7-4: Effective absorptance, α , vs. sun angle, φ, for several values of the blade

eff

angle, θ, for ATS spacecraft. From Michalek, Stipandic & Coyle (1972) [24]. ..... 81

Figure 7-5: Heat rejection capability, q, vs. sun angle, φ, for ATS spacecraft. From

Michalek, Stipandic & Coyle (1972) [24]. ............................................................ 82

Figure 7-6: Effective emittance vs. blade angle, θ, and baseplate temperature, TBP, for

sensory subsystem of NIMBUS spacecraft. From London (1967) [20]. ............... 84

Figure 7-7: Schematic blade geometry for diffuse body radiation analysis. Louvers of

the control subsystem. NIMBUS spacecraft. From London (1967) [20]. ............. 85

Figure 7-8: Effective emittance, ε , vs. blade angle, θ, for the control subsystem of

eff

NIMBUS spacecraft. From London (1967) [20]. .................................................. 85

Figure 7-9: Effective emittance, ε , vs. baseplate temperature, T , for the control

eff BP

subsystem of NIMBUS spacecraft. From London (1967) [20]. ............................ 86

Figure 7-10: Comparison of NIMBUS 1 and 2 control subsystem panel temperatures,

T , vs. orbital position. From London (1967) [20]. ............................................... 86

Figure 7-11: Overall dimensions of SNIAS louver. Not to scale. ........................................... 87

Figure 7-12: Effective emittance, ε , vs. blade angle, θ, for the SNIAS louver system.

eff

From Redor (1972) [29]. ..................................................................................... 89

Figure 7-13: Effective absorptance, α , vs. blade angle, θ, for several values of the sun

eff

angle, φ. SNIAS louver system. From Redor (1972) [29]. ................................... 91

Figure 7-14: Heat rejection capability, q, vs. blade angle, θ, for several values of the

sun angle, φ. SNIAS louver system. From Redor (1972) [29].............................. 93

Figure 7-15: Maximum blade temperature, T , vs. blade angle, θ, for several values of

the sun angle, φ. SNIAS louver system. From Redor (1972) [29]. ....................... 95

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Figure 7-16: Effective emittance, εeff, vs. blade angle, θ, for the louver system of

SNIAS. Solid line: From Redor (1972) [29]. Dashed line: From Croiset &

Leroy (1973) [8]. ................................................................................................. 96

Figure 7-17: Heat rejection capability, q, vs. blade angle, θ, for several values of the

sun angle, φ. SNIAS louver system. Solid line: From Redor (1972) [29].

Dashed line: From Croiset & Leroy (1973) [8]..................................................... 97

Figure 7-18: Temperature-pressure characteristic of the Bourdon spiral. From Reusser

et al. (1973) [30]. .............................................................................................. 100

Figure 7-19: Performance of a Bourdon actuating a single blade. After Reusser et al.

(1973) [30]. ....................................................................................................... 101

Figure 7-20: Ratios (TBP−T)/(TBP−TOL) and Q/Q0 vs. time, τ. After Reusser et al. (1973)

[30]. .................................................................................................................. 103

Tables

Table 5-1: Blade Characteristics of Existing Louver Assemblies R: Rectangular, T:

Trapezoidal ........................................................................................................ 16

Table 5-2: Materials Used .................................................................................................... 19

Table 5-3: Typical Alloy Used in Bellows D: Deposited, F: Formed, W: Welded ................... 25

Table 5-4: Typical Nonmetallic Materials Used in Bellows .................................................... 27

Table 5-5: Typical Fluids Used in Bellows ............................................................................ 28

Table 5-6: Bellows Convolutions and Relevant Characteristics ............................................ 28

Table 5-7: Spring Rate for Several Bellows .......................................................................... 30

Table 5-8: Frequency of Bellows Vibration ........................................................................... 31

Table 5-9: Characteristics of Convoluted Bellows ................................................................. 32

Table 7-1: Assumed Values of the Optical Properties of the Surfaces for the First

Computer program ............................................................................................. 77

Table 7-2: Assumed Values of the Optical Properties of the Surfaces for the Second

Computer program ............................................................................................. 77

Table 7-3: Ideal Optical Properties of the NIMBUS Louvers Surfaces .................................. 83

Table 7-4: Optical Characteristics of the Surfaces of SNIAS Louver. .................................... 87

Table 7-5: Effective Absorptance α , for Several Values of Sun Angle, φ, and Blade

eff

Angle, θ. ............................................................................................................. 90

Table 7-6: Heat Rejection Capability, q, for Several Values of Sun Angle, φ, and Blade

Angle, θ. ............................................................................................................. 92

Table 7-7: Maximum Blade Temperature, T , for Several Values of Sun Angle, φ, and

Blade Angle, θ. ................................................................................................... 94

Table 7-8: Several Characteristics of the Bourdon Spiral ...................................................... 98

Table 7-9: Several Parameters of the Bourdon Spiral ........................................................... 99

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European Foreword

This document (CEN/CLC/TR 17603-31-12:2021) has been prepared by Technical Committee

CEN/CLC/JTC 5 “Space”, the secretariat of which is held by DIN.

It is highlighted that this technical report does not contain any requirement but only collection of data

or descriptions and guidelines about how to organize and perform the work in support of EN 16603-

31.

This Technical report (TR 17603-31-12:2021) originates from ECSS-E-HB-31-01 Part 12A.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such

patent rights.

This document has been prepared under a mandate given to CEN by the European Commission and

the European Free Trade Association.

This document has been developed to cover specifically space systems and has therefore precedence

over any TR covering the same scope but with a wider domain of applicability (e.g.: aerospace).

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Scope

Thermal louvers are thermal control surfaces whose radiation characteristics can be varied in order to

maintain the correct operating temperature of a component subject to cyclical changes in the amount

of heat that it absorbs or generates.

The design and construction of louvers for space systems are described in this Part 12 and a clause is

also dedicated to providing details on existing systems.
The Thermal design handbook is published in 16 Parts
TR 17603-31-01 Thermal design handbook – Part 1: View factors
TR 17603-31-02 Thermal design handbook – Part 2: Holes, Grooves and Cavities
TR 17603-31-03 Thermal design handbook – Part 3: Spacecraft Surface Temperature
TR 17603-31-04 Thermal design handbook – Part 4: Conductive Heat Transfer

TR 17603-31-05 Thermal design handbook – Part 5: Structural Materials: Metallic and

Composite
TR 17603-31-06 Thermal design handbook – Part 6: Thermal Control Surfaces
TR 17603-31-07 Thermal design handbook – Part 7: Insulations
TR 17603-31-08 Thermal design handbook – Part 8: Heat Pipes
TR 17603-31-09 Thermal design handbook – Part 9: Radiators
TR 17603-31-10 Thermal design handbook – Part 10: Phase – Change Capacitors
TR 17603-31-11 Thermal design handbook – Part 11: Electrical Heating
TR 17603-31-12 Thermal design handbook – Part 12: Louvers
TR 17603-31-13 Thermal design handbook – Part 13: Fluid Loops
TR 17603-31-14 Thermal design handbook – Part 14: Cryogenic Cooling
TR 17603-31-15 Thermal design handbook – Part 15: Existing Satellites
TR 17603-31-16 Thermal design handbook – Part 16: Thermal Protection System
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References
EN Reference Reference in text Title
EN 16601-00-01 ECSS-S-ST-00-01 ECSS System - Glossary of terms

All other references made to publications in this Part are listed, alphabetically, in the Bibliography.

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Terms, definitions and symbols
3.1 Terms and definitions

For the purpose of this Standard, the terms and definitions given in ECSS-S-ST-00-01 apply.

3.2 Symbols
Clause 5: bellows effective area, [m ]
Clause 7: contact surface (bourdon sensing element),
[m ]
radiosity, [W.m ]
dimensionless radiosity, B* = B/σT
bellows innermost diameter, [m]
bellows outermost diameter, [m]
modulus of elasticity, [N.m ]
flexibility, [m.Pa ]
− −
2 1
coil force constant, [N.m .Angular degrees ]
energy flux impinging on the unit area, [W.m ]
heat flux to the skin arriving from outside, [W.m ]
bellows spring rate, [N.m ]
coil deflection constant, [angular degrees, K ]
Clause 5: coil active length, [m]
Clause 5: length of all convolutions in bellows, [m]
Clause 6: louver blade spacing, [m]
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length of a single convolution in bellows measured
along the surface, [m]
torsional moment of a coil, [N.m]
fluid pressure, [Pa]
proportionality limit pressure in a bourdon, [Pa]
heat transfer to the fluid within the bourdon, [J]
heat transfer to the fluid within the bourdon after an
infinitely large time, [J]
equivalent thermal resistance of the louver system, it
R(θ)
is a function of the optical properties of blades, and
inner skin surface, but for a given system R depends
only on the blade angle
coiling radius of a bourdon, [m]
mean radius of the bellows, [m]
heat flux from the space to the skin, [W.m ]
solar constant, S0 = 1353 W.m
temperature, [K]
bourdon filling fluid temperature, [K]
reference temperature, [K]
temperature differential, [K], ∆T = T−T0
starting fluid temperature, [K]
T0L
skin temperature, [K]
4 4
local dimensionless temperature, T* = T /T BP
inside volume of bellows, [m ]
sensitivity of a bimetal, [angular degrees, K ]
semi-major axis of the bourdon tube cross section, [m]
Clause 5: semi-minor axis of the bourdon tube section,
[m]
Clause 6: louver blade width, [m]
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Clause 5: numerical coefficient given in Table 5-7
under additional data
− −
1 1
Clause 7: fluid specific heat, [J.kg .K ]
defined as f(θ) = 1 - [1/R(θ)]
f(θ)
fundamental natural frequency, [s ]
fn=1
total thermal conductance of a bourdon (sensing
− −
2 1
element plus fluid, [W.m .K ]
length of a given metallic strip when the temperature
is T [m]
live length of the bellows, [m]
length of a given metallic strip when the temperature
is T0, [m]
mass of bellows active convolutions, [kg]
mass of one convolution, [kg]
mass of fluid trapped in active length at rest, [kg]
mfa
2 2
mfa = ρL[0,262(Do +DoDi)-0,524Di ]
mass of liquid within the bellows, [kg]. ml = ρAl
mass on bellows free end, [kg]
bellows mass, [kg]
louver heat rejection capability, [W.m ]
heat rejection capability for zero solar input, [W.m ]
qshadow
thickness of the strip of the coil, [m]
wall thickness for bellows or bourdon tube, [m]
width of the strip of the coil, [m]
coordinate along the louver baseplate, [m]
Coordinates along the outer and inner faces of the
y,z
blade, [m]
Φ sun angle, [angular degrees]
α absorptance
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numerical coefficient which appears in the expression
of bourdon flexibility
solar absorptance
α spectral absorptance
β Clause 5: linear thermal expansion coefficient, [K ]
Clause 5: numerical coefficient which appears in that
expression of bourdon flexibility
Clause 6: Dimensionless coordinate along the louver
baseplate, β = x/L
linear thermal expansion coefficient of the high
expansibility component of a bimetal, [K ]
linear thermal expansion coefficient of the low
expansibility component of a bimetal, [K ]
ε hemispherical total emittance
emittance of the skin inner surface
emittance of the skin outer surface
dimensionless coordinates, η = y/L, ζ = z/L
η,ζ
Clause. 5: angular deflection of a coil, [angular
degrees]
Clause 6: louver blade angle, [angular degrees]
poisson's ratio
...

SLOVENSKI STANDARD
kSIST-TP FprCEN/CLC/TR 17603-31-12:2021
01-maj-2021
Vesoljska tehnika - Priročnik za toplotno zasnovo - 12. del: Žaluzije
Space Engineering - Thermal design handbook - Part 12: Louvers
Raumfahrttechnik - Handbuch für thermisches Design - Teil 12: Luftschlitze
Ingénierie spatiale - Manuel de conception thermique - Partie 12: Persiennes
Ta slovenski standard je istoveten z: FprCEN/CLC/TR 17603-31-12
ICS:
49.140 Vesoljski sistemi in operacije Space systems and
operations
kSIST-TP FprCEN/CLC/TR 17603-31- en,fr,de
12:2021

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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kSIST-TP FprCEN/CLC/TR 17603-31-12:2021
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kSIST-TP FprCEN/CLC/TR 17603-31-12:2021
TECHNICAL REPORT
FINAL DRAFT
FprCEN/CLC/TR 17603-
RAPPORT TECHNIQUE
31-12
TECHNISCHER BERICHT
March 2021
ICS 49.140
English version
Space Engineering - Thermal design handbook - Part 12:
Louvers

Ingénierie spatiale - Manuel de conception thermique - Raumfahrttechnik - Handbuch für thermisches Design -

Partie 12: Persiennes Teil 12: Luftschlitze

This draft Technical Report is submitted to CEN members for Vote. It has been drawn up by the Technical Committee

CEN/CLC/JTC 5.

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium,

Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,

Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia,

Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a Technical Report. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a Technical Report.
CEN-CENELEC Management Centre:
Rue de la Science 23, B-1040 Brussels

reserved worldwide for CEN national Members and for
CENELEC Members.
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kSIST-TP FprCEN/CLC/TR 17603-31-12:2021
FprCEN/CLC/TR 17603-31-12:2021 (E)
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