欢迎来到麦多课文档分享! | 帮助中心 海量文档,免费浏览,给你所需,享你所想!
麦多课文档分享
全部分类
  • 标准规范>
  • 教学课件>
  • 考试资料>
  • 办公文档>
  • 学术论文>
  • 行业资料>
  • 易语言源码>
  • ImageVerifierCode 换一换
    首页 麦多课文档分享 > 资源分类 > PDF文档下载
    分享到微信 分享到微博 分享到QQ空间

    AGA 8 PART 2-2017 Thermodynamic Properties of Natural Gas and Related Gases GERG C2008 Equation of State (First Edition XQ1704-2).pdf

    • 资源ID:421868       资源大小:1.05MB        全文页数:60页
    • 资源格式: PDF        下载积分:10000积分
    快捷下载 游客一键下载
    账号登录下载
    微信登录下载
    二维码
    微信扫一扫登录
    下载资源需要10000积分(如需开发票,请勿充值!)
    邮箱/手机:
    温馨提示:
    如需开发票,请勿充值!快捷下载时,用户名和密码都是您填写的邮箱或者手机号,方便查询和重复下载(系统自动生成)。
    如需开发票,请勿充值!如填写123,账号就是123,密码也是123。
    支付方式: 支付宝扫码支付    微信扫码支付   
    验证码:   换一换

    加入VIP,交流精品资源
     
    账号:
    密码:
    验证码:   换一换
      忘记密码?
        
    友情提示
    2、PDF文件下载后,可能会被浏览器默认打开,此种情况可以点击浏览器菜单,保存网页到桌面,就可以正常下载了。
    3、本站不支持迅雷下载,请使用电脑自带的IE浏览器,或者360浏览器、谷歌浏览器下载即可。
    4、本站资源下载后的文档和图纸-无水印,预览文档经过压缩,下载后原文更清晰。
    5、试题试卷类文档,如果标题没有明确说明有答案则都视为没有答案,请知晓。

    AGA 8 PART 2-2017 Thermodynamic Properties of Natural Gas and Related Gases GERG C2008 Equation of State (First Edition XQ1704-2).pdf

    1、 AGA Report No. 8 Thermodynamic Properties of Natural Gas and Related Gases GERG2008 Equation of State First Edition April 2017 Prepared by Transmission Measurement Committee Part 2 AGA Report No. 8 Part 2 Thermodynamic Properties of Natural Gas and Related Gases GERG2008 Equation of State Prepared

    2、by Transmission Measurement Committee First Edition April 2017 Copyright 2017 American Gas Association All Rights Reserved Catalog No. XQ1704-2 ii iii DISCLAIMER AND COPYRIGHT The American Gas Associations (AGA) Operations and Engineering Section provides a forum for industry experts to bring their

    3、collective knowledge together to improve the state of the art in the areas of operating, engineering and technological aspects of producing, gathering, transporting, storing, distributing, measuring and utilizing natural gas. Through its publications, of which this is one, AGA provides for the excha

    4、nge of information within the natural gas industry and scientific, trade and governmental organizations. Many AGA publications are prepared or sponsored by an AGA Operations and Engineering Section technical committee. While AGA may administer the process, neither AGA nor the technical committee ind

    5、ependently tests, evaluates or verifies the accuracy of any information or the soundness of any judgments contained therein. AGA disclaims liability for any personal injury, property or other damages of any nature whatsoever, whether special, indirect, consequential or compensatory, directly or indi

    6、rectly resulting from the publication, use of or reliance on AGA publications. AGA makes no guaranty or warranty as to the accuracy and completeness of any information published therein. The information contained therein is provided on an “as is” basis and AGA makes no representations or warranties

    7、including any expressed or implied warranty of merchantability or fitness for a particular purpose. Nothing contained in this document should be viewed as an endorsement or disapproval of any particular manufacturer or product. In issuing and making this document available, AGA is not undertaking to

    8、 render professional or other services for or on behalf of any person or entity. Nor is AGA undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent p

    9、rofessional in determining the exercise of reasonable care in any given circumstances. AGA has no power, nor does it undertake, to police or enforce compliance with the contents of this document. Nor does AGA list, certify, test or inspect products, designs or installations for compliance with this

    10、document. Any certification or other statement of compliance is solely the responsibility of the certifier or maker of the statement. AGA does not take any position with respect to the validity of any patent rights asserted in connection with any items that are mentioned in or are the subject of AGA

    11、 publications, and AGA disclaims liability for the infringement of any patent resulting from the use of or reliance on its publications. Users of these publications are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, is ent

    12、irely their own responsibility. Users of this publication should consult applicable federal, state and local laws and regulations. AGA does not, through its publications, intend to urge action that is not in compliance with applicable laws, and its publications may not be construed as doing so. Info

    13、rmation concerning safety risks, proper installation or use, performance or fitness or suitability for any purpose with respect to particular products or materials should be obtained from the manufacturer or supplier of the material used. Changes to this document may become necessary from time to ti

    14、me. If changes are believed appropriate by any person or entity, such suggested changes should be communicated to AGA in writing and sent to: Operations full name of the document; suggested revisions to the text of the document; the rationale for the suggested revisions; and permission to use the su

    15、ggested revisions in an amended publication of the document. Copyright 2017, American Gas Association, All Rights Reserved. iv FOREWORD AGA Report No. 8, Part 2, provides technical information necessary to compute thermodynamic properties including compressibility factors, densities, speeds of sound

    16、, and dew and bubble points for natural gas and related gases. It is based on the research performed at the Ruhr University in Bochum, Germany, and published in 2006 as the doctoral dissertation of Oliver Kunz under the direction of Prof. Dr.-Ing. Wolfgang Wagner. The equations in the dissertation a

    17、re commonly referred to as the GERG-2004 and GERG-2008 equations of state in acknowledgement of partial sponsorship of the research by the Groupe Europeen de Recherches Gazieres (GERG). Because these equations are used both in this document and the International Standards Organization document ISO 2

    18、0765: Natural Gas Calculation of Thermodynamic Properties, Part 2: Single-Phase Properties (Gas, Liquid, and Dense Fluid) for Extended Ranges of Application, 2015 edition, calculations of properties should have the same values. The companion publication, AGA Report No. 8, Part 1, provides calculatio

    19、n methods for the DETAIL and GROSS equations of state as in the 1994 edition of AGA Report No. 8, but the temperature, pressure, and composition limits for different levels of uncertainties have been modified. The documentation of programs for calculating properties from the methods described in thi

    20、s document is available as supplementary material in Appendix C. Examples are available in Fortran, VB, and C+ code. The supplementary material also contains a Microsoft Excel spreadsheet for property calculations. This can be used to determine if, for a particular temperature, pressure, and composi

    21、tion, the property values calculated from the equations in Part 1 are within the desired uncertainty (by comparing with those in Part 2) even though one or more of these inputs may be outside the ranges given in Part 1. A file containing calculated points at different compositions (not necessarily r

    22、elated to typical natural gas) is included, which can be used to verify that programs or equipment have been implemented or upgraded correctly to produce values that are in agreement with the equations in this document. Some material described in Part 2 also applies to Part 1, and vice versa, and is

    23、 not repeated in both parts. For example, Part 1 describes an algorithm for obtaining densities through an iterative procedure that can also be used with the equations in Part 2 (and which is applied for this purpose to the GROSS, DETAIL, and GERG-2008 equations of state in the programs in the suppl

    24、ementary material). Similarly, Part 2 outlines the method for reporting calculated results and uncertainties from the equations in both parts, and also describes the experimental database available for natural gas mixtures (both binary and multicomponent systems), much of which was used in the devel

    25、opment of the equations in Part 1. Some information, however, is repeated in both parts, such as the material in Sections 2 and 3. The combination of Parts 1 whereas Part 2 extends these ranges to cover all mole fractions of these components in both the vapor and liquid phases. As with the DETAIL eq

    26、uation of state in Part 1, use of the GERG-2008 equation in Part 2 requires that the mixture be completely characterized by a component analysis before thermodynamic properties can be calculated. Because the mixture model combines the contributions from the pure fluid equations of state, the composi

    27、tion must be specified for each component. For a C6+ fraction, the amount of the fraction must be distributed among the heavy hydrocarbons. For a typical natural gas, this might include alkane hydrocarbons up to about C7 or C8 together with nitrogen and carbon dioxide. Additional components includin

    28、g nonane, decane, water, hydrogen sulfide, and helium may be present, and should not be lumped with other components as their presence can have a significant impact on some properties. Dew and bubble-points are influenced by the presence of the cryogens hydrogen, carbon monoxide, and oxygen in manuf

    29、actured gases. Trace components other than the 21 available in the model must be reassigned appropriately depending on the desired properties (see Section 8). Alkane isomers are typically combined by molar mass or boiling point with the normal alkanes and treated collectively for density or VLE appl

    30、ications. The use of a composite C6+ fraction for the heavy hydrocarbon compounds may be sufficient for density or speed of sound calculations, but detrimental in the determination of the dew point. Vapor-liquid equilibrium (VLE) calculations (which includes dew points) are most accurate when the co

    31、mpositions are known for all of the components in the mixture. Small amounts of heptanes, octanes, nonanes, decanes, and water have a significant impact on the dew-point state of the mixture. Analyses of the sensitivity of VLE calculations can help determine whether a particular approximation is sui

    32、table for a particular application. The independent variables in the Helmholtz energy equation of state are density, temperature, and molar composition. These properties must be known before all other thermodynamic properties can be calculated directly. When only pressure, temperature, and molar com

    33、position are available as the input variables, it is necessary to use an iterative solution to determine the density required as the independent variable in the equation of state. Multiple iterative solutions are available for such density-search algorithms, with the appropriate method dependent on

    34、the complexity of an application. If all state points are known to be single phase and within the gas region, the most successful search algorithms generally make use of the first and possibly second derivatives of pressure with respect to density to quickly locate the root. Away from the critical r

    35、egion, such an algorithm can converge within four to six steps depending on the value of the initial guess, the magnitude of the pressure or density (with dense states requiring additional steps to locate the root), and the desired tolerance in the search algorithm. Multi-term equations of state hav

    36、e several roots in the two-phase region, and verification that a root is stable adds to the complexity of the procedure. The composition in mole fractions is required for the following 21 components: methane, nitrogen, carbon dioxide, ethane, propane, isobutane, n-butane, isopentane, n-pentane, n-he

    37、xane, n-heptane, n-octane, n-nonane, n-decane, hydrogen, oxygen, carbon monoxide, water, hydrogen sulfide, helium, and argon. The allowable ranges of mole fractions are defined in Section 5. The compositions of all mole fractions shall sum to one. Compositions given in volume or mass fractions need

    38、to be converted to mole fractions, see GPA 2177, Analysis of Natural Gas Liquid Mixtures Containing Nitrogen and Carbon Dioxide by Gas Chromatography or ISO 14912, Gas Analysis Conversion of Gas Mixture Composition Data. 3 2 DEFINITIONS AND GENERAL EQUATIONS 2.1 Definitions of Phase Regions As in Pa

    39、rt 1, Part 2 puts forth a new approach to define the gas phase, dense phase, and liquid phase of a mixture. Figure 1 shows the phase boundary of a natural gas mixture with about 83 % methane. The heaviest hydrocarbons are heptane with a mole percent composition of 0.027 %, octane with 0.017 %, and n

    40、onane with 0.0009 %, where these three components play the largest role in the upper temperature and pressure limits of the saturation boundaries. Although a fluid transitions smoothly from vapor to liquid without discontinuities when the path is such that it does not cross the phase boundary, defin

    41、ed regions are useful to give a general indication of the fluids state. Most definitions of the phase regions use pressure and temperature parameters for bounding the gas, liquid, and dense regions, resulting in different parsing techniques with varying degrees of complexity depending on a groups po

    42、int of view. Most of these bounding techniques result in some inappropriately labeled areas, e.g., more gas-like than dense-like or vice-versa, due to the extent to which a certain bounding box extends into a temperature or pressure space. As shown in Figure 1, the three phase regions are now define

    43、d in terms of the critical density only. (The critical point is the state where the co-existing liquid and vapor phases have the same density and composition.) The gas phase is the region with densities less than 50 % of the critical density. Liquids are defined as states with densities greater than

    44、 125 % of the critical density. The dense phase of a fluid is any single-phase state between these two areas, i.e., a state with a density greater than 50 % and less than 125 % of the critical density. Other points or curves are also shown in Figure 1, including the cricondentherm (maximum 2-phase t

    45、emperature), the cricondenbar (maximum 2-phase pressure), the bubble point curve, the dew point curve, and the retrograde curve. In the dense phase region near the critical point for any pure fluid or mixture, the properties change rapidly as the state approaches the critical point. For example, for

    46、 a pure fluid the isobaric heat capacity increases to infinity and the speed of sound approaches zero. For temperatures near the critical point, the area between 50 % and 125 % of the critical density represents states where property changes become more significant. There are various approaches that

    47、 can be used to determine the critical density of a mixture, such as the tools available in Reference 4 that use the GERG-2008 equation of state to locate the critical point. The use of cubic equations of state (PR, SRK, etc.), though not as accurate as the GERG-2008, will determine a state point th

    48、at is in the general vicinity of the true critical point of the mixture when volume translation is applied. The simplest but least accurate approach is to use a mole fraction average of the critical volumes of the pure fluids (the critical density would then be the reciprocal of the critical volume)

    49、. The approach taken depends on the needs of a particular application. 4 Figure 1. Example of gas, liquid, and dense phase regions of a natural gas mixture. 2.2 Nomenclature a Molar Helmholtz energy (J/mol) B Second virial density coefficient (dm3/mol) c Density exponent cp Molar isobaric heat capacity J/(molK) cv Molar isochoric heat capacity J/(molK) C Third virial coefficient (dm6/mol2) d Molar density (mol/dm3) d Density exponent Dc Critical density (mol/dm3) fi Fugacity of component i (MPa) F Mixture parameter g Molar Gibbs energy (J/mol) h Molar enthalpy (J/mol)


    注意事项

    本文(AGA 8 PART 2-2017 Thermodynamic Properties of Natural Gas and Related Gases GERG C2008 Equation of State (First Edition XQ1704-2).pdf)为本站会员(sumcourage256)主动上传,麦多课文档分享仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知麦多课文档分享(点击联系客服),我们立即给予删除!




    关于我们 - 网站声明 - 网站地图 - 资源地图 - 友情链接 - 网站客服 - 联系我们

    copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
    备案/许可证编号:苏ICP备17064731号-1 

    收起
    展开