Year 2018, Volume 21, Issue 1, Pages 38 - 53 2018-03-01

Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case

Todd Nichols [1] , Vivek Utgikar [2]

120 517

The predictive error in vapor pressure of limited-data Wagner constants relative to that of entire-curve constants is studied for eleven data intervals.  Good precision is assumed for data inputs, four digits in the mantissa of Ln Pv,r and five digits for Tr.  An algebraic solution for the fully-determined case based on only four data points is used to estimate Wagner constants.  Seventy-two species are used to assess the impact of the location of the two interior points and the location and width of the limited-data interval upon the error in predicted Pv,r due to data imprecision.  Hydrogen, helium, R152a, and water are used to assess error due to Wagner imperfection and compare predictive capability of the algebraic fully-determined and regressed over-determined approaches.  The results indicate that limited VLE data of good precision from reduced temperature intervals with a width ≥ 0.1 and a lower bound ≤ 0.6 can generally provide reasonable VLE predictions over the entire two-phase curve for pure substances, with average error of approximately 1%.  It is shown that the algebraic, fully-determined solution presented is a viable tool for investigating the extensibility of limited-data Wagner constants.

Wagner equation, vapor-liquid equilibrium, pure substances, t* test, least-squares regression, fully-determined solution, equation imperfection, data imprecision
  • Dr. Ahmed Bellagi U. R. Thermique et Thermodynamique des Procedes Industriels, Ecole Nationale d'ingenieurs de Monastir (E.N.I.M.), Avenue Ibn El Jazzar, 5060 Monastir, Tunisia E-mail address: a.bellagi@enim.rnu.tn
  • Dr. Santiago Velasco Departamento de Fisica Aplicada, Universidad de Salamanca, E-37008 Salamanca, Spain E-mail: santi@usal.es
  • Dr. Joachim Gross Institute of Thermodynamics and Thermal Process Engineering, University of Stuttgart, Pfaffenwaldring 9, D-70569 Stuttgart, Germany E-mail: gross@itt.uni-stuttgart.de
Primary Language en
Subjects Engineering
Journal Section Regular Original Research Article
Authors

Author: Todd Nichols (Primary Author)
Institution: University of Idaho
Country: United States


Author: Vivek Utgikar
Institution: University of Idaho
Country: United States


Dates

Publication Date: March 1, 2018

Bibtex @research article { ijot372148, journal = {International Journal of Thermodynamics}, issn = {1301-9724}, eissn = {2146-1511}, address = {Uluslararası Uygulamalı Termodinamik Derneği İktisadi İşletmesi}, year = {2018}, volume = {21}, pages = {38 - 53}, doi = {10.5541/ijot.372148}, title = {Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval \& Fully-Determined Case}, key = {cite}, author = {Nichols, Todd and Utgikar, Vivek} }
APA Nichols, T , Utgikar, V . (2018). Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case. International Journal of Thermodynamics, 21 (1), 38-53. DOI: 10.5541/ijot.372148
MLA Nichols, T , Utgikar, V . "Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case". International Journal of Thermodynamics 21 (2018): 38-53 <http://dergipark.org.tr/ijot/issue/35770/372148>
Chicago Nichols, T , Utgikar, V . "Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case". International Journal of Thermodynamics 21 (2018): 38-53
RIS TY - JOUR T1 - Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case AU - Todd Nichols , Vivek Utgikar Y1 - 2018 PY - 2018 N1 - doi: 10.5541/ijot.372148 DO - 10.5541/ijot.372148 T2 - International Journal of Thermodynamics JF - Journal JO - JOR SP - 38 EP - 53 VL - 21 IS - 1 SN - 1301-9724-2146-1511 M3 - doi: 10.5541/ijot.372148 UR - https://doi.org/10.5541/ijot.372148 Y2 - 2018 ER -
EndNote %0 International Journal of Thermodynamics Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case %A Todd Nichols , Vivek Utgikar %T Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case %D 2018 %J International Journal of Thermodynamics %P 1301-9724-2146-1511 %V 21 %N 1 %R doi: 10.5541/ijot.372148 %U 10.5541/ijot.372148
ISNAD Nichols, Todd , Utgikar, Vivek . "Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case". International Journal of Thermodynamics 21 / 1 (March 2018): 38-53. https://doi.org/10.5541/ijot.372148
AMA Nichols T , Utgikar V . Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case. International Journal of Thermodynamics. 2018; 21(1): 38-53.
Vancouver Nichols T , Utgikar V . Wagner Equation Predicting Entire Curve for Pure Fluids from Limited VLE Data: Error Dependency Upon Data Interval & Fully-Determined Case. International Journal of Thermodynamics. 2018; 21(1): 53-38.