1、BSI Standards PublicationBS EN 16603-32-03:2014Space engineering Structuralfinite element modelsBS EN 16603-32-03:2014 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN16603-32-03:2014.The UK participation in its preparation was entrusted to TechnicalCommittee ACE
2、/68, Space systems and operations.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Instituti
3、on 2014. Published by BSI StandardsLimited 2014ISBN 978 0 580 83983 2ICS 49.140Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 August 2014.Amendments issued sin
4、ce publicationDate Text affectedBS EN 16603-32-03:2014EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16603-32-03 August 2014 ICS 49.140 English version Space engineering - Structural finite element models Ingnierie spatiale - Modles lments finis pour les structures Raumfahrttechnik - Strukturm
5、odelle der finiten Elemente Methode This European Standard was approved by CEN on 10 February 2014. CEN and CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alt
6、eration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN and CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other
7、 language made by translation under the responsibility of a CEN and CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN and CENELEC members are the national standards bodies and national electrotechnical committees
8、of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain
9、, Sweden, Switzerland, Turkey and United Kingdom. CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved worldwide for CEN national Members and for CENELEC Members. Ref. No. EN 16603-32-03:2014 EBS EN 16603-3
10、2-03:2014EN 16603-32-03:2014 (E) 2 Table of contents Foreword 4 Introduction 5 1 Scope . 6 2 Normative references . 7 3 Terms, definitions and abbreviated terms 8 3.1 Terms from other standards 8 3.2 Terms specific to the present standards . 8 3.3 Abbreviated terms. 9 3.4 Symbols 10 4 General requir
11、ements. 11 4.1 Overview 11 4.2 Coordinate systems and unit system 11 4.3 Modelling requirements 12 4.4 Requirements for reduced models 12 5 Model checks 14 5.1 General . 14 5.2 Model geometry checks for non reduced models 14 5.3 Elements topology checks for non reduced models 14 5.4 Rigid body motio
12、n checks for reduced and non reduced models 15 5.4.1 Overview . 15 5.4.2 Rigid body motion mass matrix . 15 5.4.3 Rigid body motion strain energy and residual forces check . 15 5.5 Static analysis checks for reduced and non reduced models 16 5.6 Stress free thermo-elastic deformation check for non r
13、educed models . 17 5.7 Modal analysis checks 18 5.8 Reduced model versus non reduced model consistency checks . 18 6 Test Analysis correlation 19 6.1 Overview 19 BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 3 6.2 Provisions . 19 Bibliography . 20 BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 4 Fore
14、word This document (EN 16603-32-03:2014) has been prepared by Technical Committee CEN/CLC/TC 5 “Space”, the secretariat of which is held by DIN. This standard (EN 16603-32-03:2014) originates from ECSS-E-ST-32-03C. This European Standard shall be given the status of a national standard, either by pu
15、blication of an identical text or by endorsement, at the latest by February 2015, and conflicting national standards shall be withdrawn at the latest by February 2015. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CEN
16、ELEC shall not be held responsible for identifying any or all such patent rights. This document has been developed to cover specifically space systems and has therefore precedence over any EN covering the same scope but with a wider domain of applicability (e.g. : aerospace). According to the CEN-CE
17、NELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary,
18、Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 5 Introduction The concept of model is of primary importance in
19、all the fields of the science. In engineering disciplines - and specifically in structure mechanics - a model is a representation, able to describe and predict the behaviour of a structure in terms of quantifiable variables. A first step to build a model is to choose the variables which are relevant
20、 to the studied phenomenon (e.g. displacements, stress, or frequencies) and the types of relationships among them (e.g. the theories provided by elasticity, plasticity, stability, statics, or dynamics): this representation is called the physical model. The second step is to build a mathematical repr
21、esentation (e.g. using differential equations, integral equations, or probability methods): this representation is called the mathematical model. A third step is to build a numerical model, which is a formulation of the mathematical model by means of numerical algorithms, based on several approaches
22、 (e.g. the finite element method, the boundary method, or the finite difference method). A finite element model of a structure is such a type of numerical model of structure behaviours. This Standard is restricted only to the requirements for finite element models of space structures, to be fulfille
23、d to ensure modelling quality, i.e. the correct use of this specific technology the finite element method - and the acceptance of the results. BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 6 1 Scope ECSS-E-ST-32-03 (Space engineering Structural finite element models) defines the requirements for fin
24、ite element models used in structural analysis. This Standard specifies the requirements to be met by the finite element models, the checks to be performed and the criteria to be fulfilled, in order to demonstrate model quality. The Standard applies to structural finite element models of space produ
25、cts including: launch vehicles, transfer vehicles, re-entry vehicles, spacecraft, landing probes and rovers, sounding rockets, payloads and instruments, and structural parts of all subsystems. This standard may be tailored for the specific characteristics and constrains of a space project in conform
26、ance with ECSS-S-ST-00. BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 7 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this ECSS Standard. For dated references, subsequent amendments to, or revision of any o
27、f these publications, do not apply. However, parties to agreements based on this ECSS Standard are encouraged to investigate the possibility of applying the more recent editions of the normative documents indicated below. For undated references, the latest edition of the publication referred to appl
28、ies. EN reference Reference in text Title EN 16601-00-01 ECSS-S-ST-00-01 ECSS system Glossary of terms EN 16603-32 ECSS-E-ST-32 Space engineering Structural general requirements BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 8 3 Terms, definitions and abbreviated terms 3.1 Terms from other standards
29、For the purpose of this Standard, the terms and definitions from ECSS-S-ST-00-01 and ECSS-E-ST-32 apply. 3.2 Terms specific to the present standards 3.2.1 constrained DOF DOF which has a known value, given as input 3.2.2 degrees of freedom scalar components of the solution vector in the FE method NO
30、TE Examples of DOF are displacement and rotation components, and other physical quantities as beam warping variable, or modal coordinates. 3.2.3 dependent DOF DOF which is computed from the values of other DOF, by means of a multi-constraint equation, provided as additional modelling input NOTE Exam
31、ples of multi-constraint equations are the rigid body relationship of two or more DOFs. 3.2.4 dynamic reduction (also referred as dynamic condensation) method to reduce the FE model size by means of a transformation of the full set of FE DOFs in a set of modal coordinates, and a subset of retained d
32、isplacement and rotation components NOTE There are several methods of dynamic reduction (e.g. Craig-Bampton, MacNeal). 3.2.5 free DOF unconstrained independent DOF 3.2.6 modal DOFs (also referred as modal coordinates) DOFs related to a basis of dynamic eigenmodes BS EN 16603-32-03:2014EN 16603-32-03
33、:2014 (E) 9 3.2.7 output transformation matrix matrix which pre-multiplies the reduced model DOF vector or its time derivatives to obtain the value of remaining non-retained DOFs and output variables (e.g. element force and stress) 3.2.8 quantifiable structure variable structure property which can b
34、e measured and is chosen to quantify a structure behaviour NOTE Examples of quantifiable structure variables are: displacements, stresses, natural frequencies, material properties, element properties, loads, temperatures. 3.2.9 rigid body motion matrix matrix which has as columns the vectors of rigi
35、d body displacements 3.2.10 size of FE model number of all the DOFs of the FE model 3.2.11 static reduction (also referred as static condensation) method to reduce the number of the DOFs in a model by means of a reduction transformation matrix or constraint modes matrix. NOTE Guyan reduction is a wi
36、dely employed method of static reduction. 3.2.12 structural model representation of a specific structure behaviour - described by a chosen sets of quantifiable structure variables - by means of relationships which predict the values of variables subset (named output variables) as depending from the
37、remaining variables (named input variables) 3.3 Abbreviated terms For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01 and the following apply: Abbreviation Meaning DOF degree of freedom FE finite element OTM output transformation matrix BS EN 16603-32-03:2014EN 16603-32-03:2
38、014 (E) 10 3.4 Symbols The following symbols are defined and used within this Standard: Symbol Meaning ER rigid body motion strain energy matrix FR rigid body motion residual nodal force vector K stiffness matrix M mass matrix R rigid body motion matrix BS EN 16603-32-03:2014EN 16603-32-03:2014 (E)
39、11 4 General requirements 4.1 Overview The Finite Element (FE) models are categorized as follows: Non-reduced models: defined only by nodes and finite elements (with their properties), and using as DOFs the node displacements and rotations. Statically reduced models: defined by nodes and matrices ob
40、tained from static reduction, and using as DOFs the node displacements and rotations. Dynamically reduced models: defined by nodes and matrices obtained from dynamic reduction, and using as DOFs both modal coordinates and node displacements and rotations. NOTE 1 Reduced models are also referred to a
41、s condensed models. NOTE 2 Combinations of non-reduced and reduced models can be used. 4.2 Coordinate systems and unit system a. All local coordinate systems of the mathematical model shall refer, directly or indirectly, to a unique local coordinate system that is defined with respect to the basic c
42、oordinate system. NOTE 1 The basic coordinate system is a Cartesian rectangular system having the origin in x=0; y=0; z=0. NOTE 2 The requirement allows easy merging of different FE models. b. The following units should be used for FE models: 1. meter, for length 2. kilogram, for mass 3. second, for
43、 time 4. newton, for force. BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 12 4.3 Modelling requirements a. Modelling guidelines shall be established and agreed with the customer. NOTE Guidelines are established at least on the following modeling aspects: Types of elements to be used or avoided Aspec
44、t ratio thresholds for the elements Warping threshold for shell elements Types of springs to be avoided (e.g. non-zero length) Types of permitted rigid elements Modelling of the offset of elements Modelling of bolted and riveted connections Specific aspects of dynamic models Specific aspects of the
45、thermal stress models (e.g. ability to represent temperature discontinuities due for instance to thermal washer) Specific aspects of non-linear analysis models Specific aspects for axi-symmetric models, cyclic symmetry models and Fourier series development Suggested, required and to-be-avoided analy
46、sis related parameters Mesh density Mesh refinement Interface definition Numbering rules Coordinate system definition Definition of equivalent properties Fluid effects (e.g. sloshing, added mass) 4.4 Requirements for reduced models a. The static behaviour of the structure shall be described by the r
47、educed stiffness and mass matrices, and reduced force vector relative to the retained degrees of freedom. b. The dynamic behaviour of the structure shall be described by the reduced stiffness, mass and damping matrices, and reduced force vector relative to the retained degrees of freedom. c. The red
48、uced model shall be supplied with related instructions for model integration. BS EN 16603-32-03:2014EN 16603-32-03:2014 (E) 13 d. The modal DOFs shall be ordered in the matrices according to the mode numbering sequence. e. The numbering range of the modal DOFs shall be outside of numbering ranges of
49、 other DOFs (e.g. node displacements). f. Output Transformation Matrices (OTMs) shall be provided and separated according to the type of output. g. OTMs shall be supplied with related user instructions and output item lists. h. A specific format of reduced matrices and OTMs shall be agreed with the customer. i. OTMs shall be verified by consistency with non reduced model (see clause 5.8) j. OTMs provided for the recovery of displacements and displacement-related data (e.g. element stresses, element forces, constrai
