1、Designation: E1355 12An American National StandardStandard Guide forEvaluating the Predictive Capability of Deterministic FireModels1This standard is issued under the fixed designation E1355; the number immediately following the designation indicates the year oforiginal adoption or, in the case of r
2、evision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide provides a methodology for evaluating thepredictive capabilities of a fire model for a
3、 specific use. Theintent is to cover the whole range of deterministic numericalmodels which might be used in evaluating the effects of fires inand on structures.1.2 The methodology is presented in terms of four areas ofevaluation:1.2.1 Defining the model and scenarios for which theevaluation is to b
4、e conducted,1.2.2 Verifying the appropriateness of the theoretical basisand assumptions used in the model,1.2.3 Verifying the mathematical and numerical robustnessof the model, and1.2.4 Quantifying the uncertainty and accuracy of the modelresults in predicting of the course of events in similar fire
5、scenarios.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.4 T
6、his fire standard cannot be used to provide quantitativemeasures.2. Referenced Documents2.1 ASTM Standards:2E176 Terminology of Fire StandardsE603 Guide for Room Fire ExperimentsE1591 Guide for Obtaining Data for Deterministic FireModels2.2 International Standards Organization Standards:3ISO/IEC Gui
7、de 98 (2008) Uncertainty of measurement Part 3: Guide to the expression of uncertainty in measure-mentISO 13943 (2008) Fire safety VocabularyISO 16730 (2008) Fire safety engineering Assessment,verification and validation of calculation methods3. Terminology3.1 Definitions: For definitions of terms u
8、sed in this guideand associated with fire issues, refer to terminology containedin Terminology E176 and ISO 13943. In case of conflict, thedefinitions given in Terminology E176 shall prevail.3.2 Definitions of Terms Specific to This Standard:3.2.1 model evaluationthe process of quantifying theaccura
9、cy of chosen results from a model when applied for aspecific use.3.2.2 model validationthe process of determining thedegree to which a calculation method is an accurate represen-tation of the real world from the perspective of the intendeduses of the calculation method.3.2.2.1 DiscussionThe fundamen
10、tal strategy of validationis the identification and quantification of error and uncertaintyin the conceptual and computational models with respect tointended uses.3.2.3 model verificationthe process of determining thatthe implementation of a calculation method accurately repre-sents the developers c
11、onceptual description of the calculationmethod and the solution to the calculation method.3.2.3.1 DiscussionThe fundamental strategy of verifica-tion of computational models is the identification and quanti-fication of error in the computational model and its solution.3.2.4 The precision of a model
12、refers to the deterministiccapability of a model and its repeatability.3.2.5 The accuracy refers to how well the model replicatesthe evolution of an actual fire.4. Summary of Guide4.1 A recommended process for evaluating the predictivecapability of fire models is described. This process includes abr
13、ief description of the model and the scenarios for whichevaluation is sought. Then, methodologies for conducting ananalysis to quantify the sensitivity of model predictions tovarious uncertain factors are presented, and several alternatives1This guide is under the jurisdiction ofASTM Committee E05 o
14、n Fire Standardsand is the direct responsibility of Subcommittee E05.33 on Fire Safety Engineering.Current edition approved April 1, 2012. Published April 2012. Originallyapproved in 1990. Last previous edition approved in 2011 as E1355 11. DOI:10.1520/E1355-12.2For referenced ASTM standards, visit
15、the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute, 11 West 42nd Street,13th Floor, New York, NY
16、 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.for evaluating the accuracy of the predictions of the model areprovided. Historically, numerical accuracy has been concernedwith time step size and errors. A more complete evalua
17、tionmust include spatial discretization. Finally, guidance is givenconcerning the relevant documentation required to summarizethe evaluation process.5. Significance and Use5.1 The process of model evaluation is critical to establish-ing both the acceptable uses and limitations of fire models. It isn
18、ot possible to evaluate a model in total; instead, this guide isintended to provide a methodology for evaluating the predic-tive capabilities for a specific use. Validation for one applica-tion or scenario does not imply validation for different sce-narios. Several alternatives are provided for perf
19、orming theevaluation process including: comparison of predictionsagainst standard fire tests, full-scale fire experiments, fieldexperience, published literature, or previously evaluated mod-els.5.2 The use of fire models currently extends beyond the fireresearch laboratory and into the engineering,
20、fire service andlegal communities. Sufficient evaluation of fire models isnecessary to ensure that those using the models can judge theadequacy of the scientific and technical basis for the models,select models appropriate for a desired use, and understand thelevel of confidence which can be placed
21、on the resultspredicted by the models.Adequate evaluation will help preventthe unintentional misuse of fire models.5.3 This guide is intended to be used in conjunction withother guides under development by Committee E05. It isintended for use by:5.3.1 Model DevelopersTo document the usefulness of ap
22、articular calculation method perhaps for specific applications.Part of model development includes identification of precisionand limits of applicability, and independent testing.5.3.2 Model UsersTo assure themselves that they areusing an appropriate model for an application and that itprovides adequ
23、ate accuracy.5.3.3 Developers of Model Performance CodesTo be surethat they are incorporating valid calculation procedures intocodes.5.3.4 Approving OffcialsTo ensure that the results ofcalculations using mathematical models stating conformance tothis guide, cited in a submission, show clearly that
24、the modelis used within its applicable limits and has an acceptable levelof accuracy.5.3.5 EducatorsTo demonstrate the application and ac-ceptability of calculation methods being taught.5.4 This guide is not meant to describe an acceptance testingprocedure.5.5 The emphasis of this guide is numerical
25、 models of fireevolution.5.5.1 The precision of a model refers to the deterministiccapability of a model and its repeatability.5.5.2 The accuracy of a model refers to how well the modelreplicates the evolution of an actual fire.6. General Methodology6.1 The methodology is presented in terms of four
26、areas ofevaluation:6.1.1 Defining the model and scenarios for which theevaluation is to be conducted,6.1.2 Assessing the appropriateness of the theoretical basisand assumptions used in the model,6.1.3 Assessing the mathematical and numerical robustnessof the model, and6.1.4 Quantifying the uncertain
27、ty and accuracy of the modelresults in predicting the course of events in similar firescenarios.6.1.5 This general methodology is also consistent with themethodology presented in ISO 16730, Fire safety engineering Assessment, verification and validation of calculation meth-ods, which is a potentiall
28、y useful resource which can be usedwith ASTM E1355.6.2 Model and Scenario Documentation:6.2.1 Model DocumentationSufficient documentation ofcalculation models, including computer software, is absolutelynecessary to assess the adequacy of the scientific and technicalbasis of the models, and the accur
29、acy of computationalprocedures. Also, adequate documentation will help preventthe unintentional misuse of fire models. Guidance on thedocumentation of computer-based fire models is provided inSection 7.6.2.2 Scenario DocumentationProvide a complete de-scription of the scenarios or phenomena of inter
30、est in theevaluation to facilitate appropriate application of the model, toaid in developing realistic inputs for the model, and to developcriteria for judging the results of the evaluation. Detailsapplicable to evaluation of the predictive capability of firemodels are provided in 7.2.6.3 Theoretica
31、l Basis and Assumptions in the ModelAnindependent review of the underlying physics and chemistryinherent in a model ensures appropriate application of submod-els which have been combined to produce the overall model.Details applicable to evaluation of the predictive capability offire models are prov
32、ided in Section 8.6.4 Mathematical and Numerical RobustnessThe com-puter implementation of the model should be checked to ensuresuch implementation matches the stated documentation. De-tails applicable to evaluation of the predictive capability of firemodels are provided in Section 9. Along with 6.3
33、, thisconstitutes verification of the model.6.5 Quantifying the Uncertainty and Accuracy of the Model:6.5.1 Model UncertaintyEven deterministic models relyon inputs often based on experimental measurements, empiri-cal correlations, or estimates made by engineering judgment.Uncertainties in the model
34、 inputs can lead to correspondinguncertainties in the model outputs. Sensitivity analysis is usedto quantify these uncertainties in the model outputs based uponknown or estimated uncertainties in model inputs. Guidancefor obtaining input data for fire models is provided by GuideE1591. Details of sen
35、sitivity analysis applicable to evaluationof the predictive capability of fire models are provided inSection 10.E1355 1226.5.2 Experimental UncertaintyIn general, the result ofmeasurement is only the result of an approximation or estimateof the specific quantity subject to measurement, and thus ther
36、esult is complete only when accompanied by a quantitativestatement of uncertainty. Guidance for conducting full-scalecompartment tests is provided by Guide E603. Guidance fordetermining the uncertainty in measurements is provided in theISO Guide to the Expression of Uncertainty in Measurement.6.5.3
37、Model EvaluationObtaining accurate estimates offire behavior using predictive fire models involves insuringcorrect model inputs appropriate to the scenarios to be mod-eled, correct selection of a model appropriate to the scenariosto be modeled, correct calculations by the model chosen, andcorrect in
38、terpretation of the results of the model calculation.Evaluation of a specific scenario with different levels ofknowledge of the expected results of the calculation addressesthese multiple sources of potential error. Details applicable toevaluation of the predictive capability of fire models areprovi
39、ded in Section 11.7. Model and Scenario Definition7.1 Model DocumentationProvides details of the modelevaluated in sufficient detail such that the user of the evaluationcould independently repeat the evaluation. The followinginformation should be provided:7.1.1 Program Identification:7.1.1.1 Provide
40、 the name of the program or model, adescriptive title, and any information necessary to define theversion uniquely.7.1.1.2 Define the basic processing tasks performed, anddescribe the methods and procedures employed. A schematicdisplay of the flow of the calculations is useful.7.1.1.3 Identify the c
41、omputer(s) on which the program hasbeen executed successfully and any required peripherals,including memory requirements and tapes.7.1.1.4 Identify the programming languages and versions inuse.7.1.1.5 Identify the software operating system and versionsin use, including library routines.7.1.1.6 Descr
42、ibe any relationships to other models.7.1.1.7 Describe the history of the models development andthe names and addresses of the individual(s) and organiza-tions(s) responsible.7.1.1.8 Provide instructions for obtaining more detailedinformation about the model from the individual(s) responsiblefor mai
43、ntenance of the model.7.1.2 ReferencesList the publications and other referencematerials directly related to the fire model or software.7.1.3 Problem or Function Identification:7.1.3.1 Define the fire problem modeled or function per-formed by the program, for example, calculation of fire growth,smok
44、e spread, people movement, etc.7.1.3.2 Describe the total fire problem environment. Gen-eral block or flow diagrams may be included here.7.1.3.3 Include any desirable background information, suchas feasibility studies or justification statements.7.1.4 Theoretical Foundation:7.1.4.1 Describe the theo
45、retical basis of the phenomenonand the physical laws on which the model is based.7.1.4.2 Present the governing equations and the mathemati-cal model employed.7.1.4.3 Identify the major assumptions on which the firemodel is based and any simplifying assumptions.7.1.4.4 Provide results of any independ
46、ent review of thetheoretical basis of the model. This guide recommends areview by one or more recognized experts fully conversantwith the chemistry and physics of fire phenomena but notinvolved with the production of the model.7.1.5 Mathematical Foundation:7.1.5.1 Describe the mathematical technique
47、s, procedures,and computational algorithms employed to obtain numericalsolutions.7.1.5.2 Provide references to the algorithms and numericaltechniques.7.1.5.3 Present the mathematical equations in conventionalterminology and show how they are implemented in the code.7.1.5.4 Discuss the precision of t
48、he results obtained byimportant algorithms and any known dependence on theparticular computer facility.7.1.5.5 For iterative solutions, discuss the use and interpre-tation of convergence tests, and recommend a range of valuesfor convergence criteria. For probabilistic solutions, discuss theprecision
49、 of the results having a statistical variance.7.1.5.6 Identify the limitations of the model based on thealgorithms and numerical techniques.7.1.5.7 Provide results of any analyses that have beenperformed on the mathematical and numerical robustness ofthe model. Analytical tests, code checking, and numerical testsare among the analyses listed in this guide that are appropriatefor this purpose.7.1.6 Program Description:7.1.6.1 Describe the program.7.1.6.2 List any auxiliary programs or external data filesrequired for utilization of this program.7.1.6.3 Desc
