A Method and Apparatus for Direct Enthalpy Rise Measurement for Gas Compression

2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Klaus Brun ◽  
Sarah Simons ◽  
Kelsi Katcher ◽  
Ryan Cater ◽  
Brandon Ridens ◽  
...  
Keyword(s):  
Equation Of State ◽  
Performance Test ◽  
Elevated Temperatures ◽  
Equations Of State ◽  
Test Results ◽  
Test Apparatus ◽  
Compression Process ◽  
Test Gas ◽  
Gas Compression ◽  
Calibration Measurement

Gas property prediction is necessary for proper design of compressors. Equations of state are utilized to predict the thermo-physical gas properties needed for such calculations. These are semi-empirical models that allow the calculation of thermodynamic properties such as density, enthalpy, and speed of sound of gas mixtures for known pressures and temperature. Currently, there is limited or no data publically available to verify the results of these equation of state calculations for the range of pressures, temperatures, and gas compositions relevant to many oil and gas applications. Especially for isentropic enthalpy head (i.e., the enthalpy rise along constant entropy lines), which is a critical parameter required to accurately design and performance test compressors, limited public domain data are available for equation of state validation. In this paper, a method and test apparatus is described to measure compression enthalpy rise directly. In this apparatus, a test gas is compressed using a fast acting piston inside an adiabatic autoclave. Test results are then corrected using calibration efficiencies from a known reference gas compression process at a similar Reynolds number. The paper describes the test apparatus, calibration, measurement methodology, and test results for one complex hydrocarbon gas composition at elevated temperatures and pressures. An uncertainty analysis of the new measurement method is also presented and results are compared to several equations of state. The results show that commonly used equations of state significantly underpredicted the compression enthalpy rise for the test gas case by more than 6%.

A Method and Apparatus for Direct Enthalpy Rise Measurement for Gas Compression

2018 ◽  
Author(s):  
Klaus Brun ◽  
Sarah Simons ◽  
Kelsi Katcher ◽  
Ryan Cater ◽  
Brandon Ridens ◽  
...  
Keyword(s):  
Equation Of State ◽  
Performance Test ◽  
Elevated Temperatures ◽  
Equations Of State ◽  
Test Results ◽  
Test Apparatus ◽  
Compression Process ◽  
Test Gas ◽  
Gas Compression ◽  
Calibration Measurement

Gas property prediction is necessary for proper design of compressors. Equations of state are utilized to predict the thermo-physical gas properties needed for such calculations. These are semi-empirical models that allow the calculation of thermodynamic properties such as density, enthalpy, and speed of sound of gas mixtures for known pressures and temperature. Currently, there is limited or no data publically available to verify the results of these equation of state calculations for the range of pressures, temperatures and gas compositions relevant to many oil & gas applications. Especially for isentropic enthalpy head (i.e., the enthalpy rise along constant entropy lines), which is a critical parameter required to accurately design and performance test compressors, limited public domain data is available for equation of state validation. In this paper a method and test apparatus is described to measure compression enthalpy rise directly. In this apparatus a test gas is compressed using a fast acting piston inside an adiabatic autoclave. Test results are then corrected using calibration efficiencies from a known reference gas compression process at a similar Reynolds number. The paper describes the test apparatus, calibration, measurement methodology, and test results for one complex hydrocarbon gas composition at elevated temperatures and pressures. An uncertainty analysis of the new measurement method is also presented and results are compared to several equations of state. The results show that commonly used equations of state significantly under-predicted the compression enthalpy rise for the test gas case by more than 6%.

SITE-SPECIFIC EQUATIONS OF STATE FOR COASTAL SEA AREAS AND INLAND WATER BODIES

2017 ◽  
Author(s):  
Natalia Andrulionis ◽  
Natalia Andrulionis ◽  
Ivan Zavialov ◽  
Ivan Zavialov ◽  
Elena Kovaleva ◽  
...  
Keyword(s):  
Equation Of State ◽  
Black Sea ◽  
Water Samples ◽  
Equations Of State ◽  
Sea Water ◽  
Ionic Composition ◽  
Water Bodies ◽  
Aral Sea ◽  
The Black Sea ◽  
Coastal Sea

This article presents a new method of laboratory density determination and construction equations of state for marine waters with various ionic compositions and salinities was developed. The validation of the method was performed using the Ocean Standard Seawater and the UNESCO thermodynamic equation of state (EOS-80). Density measurements of water samples from the Aral Sea, the Black Sea and the Issyk-Kul Lake were performed using a high-precision laboratory density meter. The obtained results were compared with the density values calculated for the considered water samples by the EOS-80 equation. It was shown that difference in ionic composition between Standard Seawater and the considered water bodies results in significant inaccuracies in determination of water density using the EOS-80 equation. Basing on the laboratory measurements of density under various salinity and temperature values we constructed a new equation of state for the Aral Sea and the Black Sea water samples and estimated errors for their coefficients.

PENGARUH MODEL PEMBELAJARAN KELILING KELOMPOK (ROUND CLUB) TERHADAP KETERAMPILAN MENULIS LAPORAN PERJALANAN SISWA KELAS V SDN 01 NAGARI BUKIK SIKUMPA

2020 ◽  
Author(s):  
Wirda Linda
Keyword(s):  
Standard Deviation ◽  
Performance Test ◽  
Writing Skills ◽  
Learning Model ◽  
Homogeneity Test ◽  
Test Results ◽  
Class V ◽  
Average Value ◽  
Normality Test ◽  
Lecture Method

This research is motivated by the low desire of students in writing travel reports. The lack of students' knowledge of the report concept, the lack of students' knowledge of the 5W + 1H report points of good and correct language, the lack of students' knowledge of the spatial, time and topic pattern and not yet reached KKM 75. The method used by the teacher has not been interesting, lecture method. The purpose of this study is to describe the skills of writing travel reports by using Round Club learning model which is viewed from the aspect of understanding the report concept, the use of 5W +1H report points, the spatial, time, and topic pattern.The population of this study is the students of class V Lessons Year 2017/2018 which amounted to 2 classes with the number 80. The sample of research as much as two classes taken by the sample of propotional.Class V.1 as experimental class and class V.2 as control class. The research instrument used is performance test. Provide an assessment by specifying the subject of the 5W + 1H report, as well as the spatial, time and topic pattern. Data were analyzed by 't' test by first testing normality, homogeneity, and hypothesis testing.The results showed that the average control class 68 with more than enough qualifications with standard deviation 16.96. 83 experimental class with good qualification and standard deviation of 15.42 and there is a significant influence on the result of writing skill of class V SDN 01 Nagari Bukik SikumpaSubdistrict, Lima Puluh Kota. This is evidenced by the average value of writing skills in the experiment class higher than the average value in the control class. Normality test results indicate that the two sample classes of  Lo  values in the control class -0.2141 are smaller than the normal 0.190 Lt distributed. Homogeneity test results that the variation of this study is homogeneous at a real level of 0.05, because Ftable 2.16 > Fhitung 1.21 and the results of data analysis then obtained = 2.78 > 1.70 t table, so H0 rejected and H1 accepted. It can be concluded that there is Influence. Using  Learning  Model of Student Group Writing  Skills Travel Report of students of class V SDN 01 Nagari Bukik Sikumpa Subdistrict, Kabupaten Lima Puluh Kota.KeyWords: model pembelajaran round club, menulis laporan perjalanan.

Application of the Redlich-Kwong-Soave equation of state to the solubility of water in compressed gases

1984 ◽  
Vol 49 (5) ◽  
pp. 1116-1121
Author(s):  
Josef P. Novák ◽  
Jaroslav Matouš ◽  
Petr Pick ◽  
Jiří Pick
Keyword(s):  
Equation Of State ◽  
Binary Systems ◽  
Equations Of State ◽  
Published Data ◽  
Interaction Coefficients

Published data on the solubility of water in compressed gases were employed for calculating the interaction coefficients kij in the Redlich-Kwong-Soave equations of state for binary systems of water with argon, nitrogen, CO2, N2O, CH4, C2H6, or C2H4. With these coefficients, the estimate of the solubility of water in these gases has been improved by more than one order.

scholarly journals Global Well-Posedness of the Ocean Primitive Equations with Nonlinear Thermodynamics

2021 ◽  
Vol 23 (3) ◽  
Author(s):  
Peter Korn
Keyword(s):  
Equation Of State ◽  
Equations Of State ◽  
Boussinesq Equations ◽  
Climate Science ◽  
Rational Functions ◽  
Ocean Dynamics ◽  
Global Ocean ◽  
Primitive Equations ◽  
Well Posedness ◽  
Nonlinear Thermodynamics

AbstractWe consider the hydrostatic Boussinesq equations of global ocean dynamics, also known as the “primitive equations”, coupled to advection–diffusion equations for temperature and salt. The system of equations is closed by an equation of state that expresses density as a function of temperature, salinity and pressure. The equation of state TEOS-10, the official description of seawater and ice properties in marine science of the Intergovernmental Oceanographic Commission, is the most accurate equations of state with respect to ocean observation and rests on the firm theoretical foundation of the Gibbs formalism of thermodynamics. We study several specifications of the TEOS-10 equation of state that comply with the assumption underlying the primitive equations. These equations of state take the form of high-order polynomials or rational functions of temperature, salinity and pressure. The ocean primitive equations with a nonlinear equation of state describe richer dynamical phenomena than the system with a linear equation of state. We prove well-posedness for the ocean primitive equations with nonlinear thermodynamics in the Sobolev space $${{\mathcal {H}}^{1}}$$ H 1 . The proof rests upon the fundamental work of Cao and Titi (Ann. Math. 166:245–267, 2007) and also on the results of Kukavica and Ziane (Nonlinearity 20:2739–2753, 2007). Alternative and older nonlinear equations of state are also considered. Our results narrow the gap between the mathematical analysis of the ocean primitive equations and the equations underlying numerical ocean models used in ocean and climate science.

scholarly journals Performance Study of Grass-Derived Nano-Cellulose and Polycaprolactone Composites for 3D Printing

2021 ◽  
Vol 11 (3) ◽  
pp. 1273
Author(s):  
Chen Feng ◽  
Jiping Zhou ◽  
Xiaodong Xu ◽  
Yani Jiang ◽  
Hongcan Shi ◽  
...  
Keyword(s):  
3D Printing ◽  
Mechanical Test ◽  
Chemical Properties ◽  
Test Results ◽  
Performance Study ◽  
Compression Process ◽  
Ansys Fluent ◽  
Nano Cellulose ◽  
Physical And Chemical ◽  
And Chemical Properties

In recent years, 3D printing has received increasing attention from researchers. This technology overcomes the limitations of traditional technologies by printing precise and personalized scaffold with arbitrary shapes, pore structures, and porosities for the applications in various tissues. The cellulose nanocrystal (CNC) is extracted from Humulus Japonicus (HJS) and mixed with poly(ε-caprolactone) (PCL) to prepare a series of CNC/PCL composites for printing. Based on the analysis of the physical and chemical properties of the series of the CNC/PCL composites, an optimal mass ratio of CNC to PCL was obtained. The Solidworks was used to simulate the stretching and compression process of the scaffolds with three different patterns under an external force. The flow of nutrient solution in the scaffolds with different patterns was simulated by ANSYS FLUENT, and then a new optimization scaffold pattern with a concave hexagon shape was advised based on the simulation results. Collectively, the mechanical test results of the material and scaffold confirmed that the optimal filling amount of the CNC was 5%, and the scaffold pattern with concave hexagon shape exhibited better mechanical properties and suitable for the transport of cells and nutrients, which is expected to be more widely used in 3D printing.

scholarly journals Measuring the structure and equation of state of polyethylene terephthalate at megabar pressures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
J. Lütgert ◽  
J. Vorberger ◽  
N. J. Hartley ◽  
K. Voigt ◽  
M. Rödel ◽  
...  
Keyword(s):  
Equation Of State ◽  
Polyethylene Terephthalate ◽  
Density Functional ◽  
Equations Of State ◽  
Md Simulations ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
Shock Hugoniot ◽  
Highly Correlated

AbstractWe present structure and equation of state (EOS) measurements of biaxially orientated polyethylene terephthalate (PET, $$({\hbox {C}}_{10} {\hbox {H}}_8 {\hbox {O}}_4)_n$$ ( C 10 H 8 O 4 ) n , also called mylar) shock-compressed to ($$155 \pm 20$$ 155 ± 20 ) GPa and ($$6000 \pm 1000$$ 6000 ± 1000 ) K using in situ X-ray diffraction, Doppler velocimetry, and optical pyrometry. Comparing to density functional theory molecular dynamics (DFT-MD) simulations, we find a highly correlated liquid at conditions differing from predictions by some equations of state tables, which underlines the influence of complex chemical interactions in this regime. EOS calculations from ab initio DFT-MD simulations and shock Hugoniot measurements of density, pressure and temperature confirm the discrepancy to these tables and present an experimentally benchmarked correction to the description of PET as an exemplary material to represent the mixture of light elements at planetary interior conditions.

Physical and performance characteristics related to starter status, position, and division in Japanese collegiate American-football players

2021 ◽  
pp. 1-8
Author(s):  
Junta Iguchi ◽  
Minoru Matsunami ◽  
Tatsuya Hojo ◽  
Yoshihiko Fujisawa ◽  
Kenji Kuzuhara ◽  
...  
Keyword(s):  
Performance Test ◽  
Vertical Jump ◽  
American Football ◽  
Football Players ◽  
Jump Height ◽  
Test Results ◽  
Repetition Maximum ◽  
Vertical Jump Height ◽  
Division 1 ◽  
And Performance

BACKGROUND: Few studies have investigated the variations in body composition and performance in Japanese collegiate American-football players. OBJECTIVE: To clarify what characterizes competitors at the highest levels – in the top division or on the starting lineup – we compared players’ body compositions and performance test results. METHODS: This study included 172 players. Each player’s body composition and performance (one-repetition maximum bench press, one-repetition maximum back squat, and vertical jump height) were measured; power was estimated from vertical jump height and body weight. Players were compared according to status (starter vs. non-starter), position (skill vs. linemen), and division (1 vs. 2). Regression analysis was performed to determine characteristics for being a starter. RESULTS: Players in higher divisions and who were starters were stronger and had more power, greater body size, and better performance test results. Players in skill positions were relatively stronger than those in linemen positions. Vertical jump height was a significant predictor of being a starter in Division 1. CONCLUSION: Power and vertical jump may be a deciding factor for playing as a starter or in a higher division.

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