1、Designation:D571913Standard Guide forSimulation of Subsurface Airflow Using Groundwater FlowModeling Codes1This standard is issued under the fixed designation D5719;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last rev
2、ision.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 covers the use of a groundwater flowmodeling code to simulate the movement of air in the subsur-face.This approximation
3、is possible because the form of thegroundwater flow equations are similar in form to airflowequations.Approximate methods are presented that allow thevariables in the airflow equations to be replaced with equiva-lent terms in the groundwater flow equations.The modeloutput is then transformed back to
4、 airflow terms.1.2 This guide illustrates the major steps to take in devel-oping an airflow model using an existing groundwater flowmodeling code.This guide does not recommend the use of aparticular model code.Most groundwater flow modeling codescan be utilized,because the techniques described in th
5、is guiderequire modification to model input and not to the code.1.3 This guide is not intended to be all inclusive.Othersimilar techniques may be applicable to airflow modeling,aswell as more complex variably saturated groundwater flowmodeling codes.This guide does not preclude the use of othertechn
6、iques,but presents techniques that can be easily appliedusing existing groundwater flow modeling codes.1.4 This guide is one of a series of standards on groundwa-ter model applications,including Guides D5447 and D5490.This guide should be used in conjunction with Guide D5447.Other standards have bee
7、n prepared on environmentalmodeling,such as Practice E978.1.5 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is therespons
8、ibility 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.1.7 This guide offers an organized collection of informationor a series of options and does not recommend a specificcourse of action.This
9、 document cannot replace education orexperience and should be used in conjunction with professionaljudgment.Not all aspects of this guide may be applicable in allcircumstances.This ASTM standard is not intended to repre-sent or replace the standard of care by which the adequacy ofa given professiona
10、l service must be judged,nor should thisdocument be applied without consideration of a projects manyunique aspects.The word“Standard”in the title of thisdocument means only that the document has been approvedthrough the ASTM consensus process.2.Referenced Documents2.1 ASTM Standards:2D653 Terminolog
11、y Relating to Soil,Rock,and ContainedFluidsD5447 Guide forApplication of a Groundwater Flow Modelto a Site-Specific ProblemD5490 Guide for Comparing Groundwater Flow ModelSimulations to Site-Specific InformationE978 Practice for Evaluating Mathematical Models for theEnvironmental Fate of Chemicals(W
12、ithdrawn 2002)33.Terminology3.1 Definitions:3.1.1 For definitions of general technical terms used withinthis guide,refer to Terminology D653.3.2 Symbols:3.2.1 Across-sectional area of cell cm2.3.2.2 gacceleration due to gravity cm/s2.3.2.3 hair-phase or water phase head cm.3.2.4 kair phase permeabil
13、ity cm2.3.2.5 Khydraulic conductivity cm/s.3.2.6 Pair phase pressure g/cm-s2.1This guide is under the jurisdiction ofASTM Committee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Groundwater andVadose Zone Investigations.Current edition approved April 1,2013.Published
14、 April 2013.Originallyapproved in 1995.Last previous edition approved in 2006 as D5719 95(2006).DOI:10.1520/D5719-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the
15、standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.7 P0reference air-phase pressure g/cm-s2.3.2.8 qssp
16、ecific discharge vector for air cm/s.3.2.9 qvolumetric flow of water through cell cm3/s.3.2.10 q*model-computed term related to airflow in unitsg2-cm/s4.3.2.11 qvvolumetric airflow cm3/s.3.2.12 qmmass airflow g/s.3.2.13 Runiversal gas constant=8.314 107g-cm2/s2-mol-K.3.2.14 Saair storage coefficient.3.2.15 Ssspecific storage of the porous material cm1.3.2.16 ttime s.3.2.17 Ttemperature K.3.2.18 zelevation head cm.3.2.19 hhydraulic head difference cm.3.2.20 llength of model cell cm.3.2.21 density
