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Saturation pressures of pure R-1336mzz(Z) and R-1130(E) and bubble point pressures of three R-1336mzz(Z)/1130(E) blends were measured from 265 K to 360 K. For each pure refrigerant or refrigerant blend, a total of twenty unique saturation pressures or bubble points were measured. In total 100 unique state points were obtained. Presently, no Helmholtz-energy-explicit type equation of state (EoS) is available for R-1130(E). While an extended corresponding states EoS for R-1130(E) is available to estimate the properties of the R-1336mzz(Z)/1130(E) blend, this model does not resolve the azeotropic behavior of the mixture. Therefore, the perturbed-chain statistical-associating fluid theory (PC-SAFT) EoS is used to model the vapor–liquid equilibria of the R-1336mzz(Z)/1130(E) blend. PC-SAFT model parameters are reported, and the overall performance of the model is characterized by deviations from the experimental data. [ABSTRACT FROM AUTHOR]

The present work investigated the effects of some non‐condensable impurities (i.e., N2, O2, CH4, and Ar) on the phase behaviour of CO2‐rich systems at low temperature conditions (228.15–273.15 K). The study focused on bubble point measurements of CO2‐rich systems using the isothermal (pressure–volume) method at different mole fractions of CO2 (99.5%–95%). The obtained experimental data were used to validate multi‐fluid Helmholtz energy approximation (MFHEA) and Peng–Robinson (PR) equations of state (EoSs). For all data points, the measurements' uncertainties for temperature and pressure were 0.14 K and 0.03 MPa, respectively. While the composition uncertainty of the CO2 systems was a maximum of 0.024%. The findings reveal that as the mole fractions of the impurities increased, the bubble point pressures of the binary mixtures were elevated. Among all the investigated impurities, N2 has the most significant effect on the bubble point pressures of CO2 binary mixture at all the isotherms and compositions. Both MFHEA and PR models agreed well with the measured equilibrium points. For all systems, the average absolute deviations of the measured experimental data against the MFHEA and PR EoSs, were found to be less than 3.4% and 2.2%, respectively. Although the MFHEA EoS overpredicted most of the data points, the overall trend agreed with the experimental data and was consistent with the data available in the literature. The findings imply that the presence of these non‐condensable impurities (even as low as 0.5% mole fraction) increases the risk of two‐phase flow at higher pressures in a CO2‐rich system. © 2023 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

To enable future deep space exploration, orbital refueling of spacecraft is essential. However, transferring liquid in a microgravity environment is a complex process dependent on various factors. One of the basic and critical tasks is to separate phases to allow the supply of gas-free liquid from one tank to another. For this purpose, a liquid acquisition device is essential. In this work, a screen channel liquid acquisition device was designed and used to investigate phase separation and liquid removal from an experiment tank in a microgravity environment. The experiments were performed using the drop tower facility at the University of Bremen, with HFE-7500 as the test liquid under isothermal conditions. This investigation explored the interdependent effects of various phenomena, including the reorientation of liquid in the tank, capillary rise between parallel plates, flow through screen pressure variation, and bubble point breakthrough. Under subcritical conditions, the SC-LAD was found to supply gas-free liquid at the outlet, as long as the pressure drop across the screen was lower than the bubble point threshold. At the critical point, the screen started to ingest bubbles, resulting in a sharp peak in the differential pressure signal. The wetted area of the screen was obtained by analyzing images captured with a high-speed camera and used to calculate the analytical pressure drop. The experimental results were compared with the analytical solution and discussed in detail. [ABSTRACT FROM AUTHOR]

The development of porous ceramic screens with high chemical stability, low density, and thermal conductivity can lead to promising screen channel liquid acquisition devices (SC-LADs) for propellant management under microgravity conditions in the future. Therefore, SiOC screens with aligned pores were fabricated via freeze-casting and applied as a SC-LAD. The pore window sizes and open porosity varied from 6 µm to 43 µm and 65% or 79%, depending on the freezing temperature or the solid loading, respectively. The pore window size distributions and bubble point tests indicate crack-free screens. On the one hand, SC-LADs with an open porosity of 79% removed gas-free liquid up to a volumetric flow rate of 4 mL s−1. On the other hand, SC-LADs with an open porosity of 65% were limited to 2 mL s−1 as the pressure drop across these screens was relatively higher. SC-LADs with the same open porosity but smaller pore window sizes showed a higher pressure drop across the screen and bubble ingestion at higher values of effective screen area when increasing the applied removal volumetric flow rate. The removed liquid from the SC-LADs was particle-free, thus representing a potential for applications in a harsh chemical environment or broad-range temperatures. [ABSTRACT FROM AUTHOR]

Vapor pressure data and evaporation/sublimation rate of liquid and solid samples are key parameters for designing new process units in terms of design, operability, and safety. In addition, for the case of hazardous materials, health and environmental aspects become essential. Conventional methods for obtaining these data mostly require significant material, time, and energy. Thermal analysis methods including differential scanning calorimetry (DSC) and thermogravimetry (TG) can both offer a platform for studying transition behavior of liquids/solids to the vapor phase. Yet, there are limitations, operational considerations, and analysis precautions to be accounted for in order to obtain highly valuable data. In particular, specific cautions should be taken for the case of liquid mixtures. Therefore, it is essential that the fundamentals and underlying principles of using DSC and TG methods for vapor pressure data generation are comprehensively understood so that one can effectively tune the methods according to the specific nature of the study. The dynamic nature of these methods develops a quasi-equilibrium state, where one should attempt to optimize the conditions as such that the temperature program effect becomes negligible on the initial condition of the sample. In this work, an integrative approach is followed to discuss the fundamentals and operational aspects of using DSC and TG for generating accurate vaporization and vapor pressure data of liquid samples. Specific attention is dedicated to elaborate on optimizing not only the experimental conditions to achieve isothermal boiling, but also data analysis step. Therefore, different considerations regarding post-run analysis are discussed. Moreover, due to the high importance of hydrocarbons, specific attention is also given to the application of these two methods to obtain vapor pressure data of hydrocarbons. The constructive discussions in this work develop an overview of the fundamentals of the method, provide the most significant contributions to the topic in a unifying manner, and suggest inputs and highlight the limitations of the techniques for future studies. [ABSTRACT FROM AUTHOR]

Production from the North Sea reservoirs often results in a pressure decrease below the bubble point. The gas is liberated from oil, in the form of bubbles or as a continuous flowing phase. In such cases, the two phases, gas and oil, flow in the reservoir simultaneously, and the flow is governed by the values of relative permeabilities. Traditional core flooding in low permeability rocks is challenging, therefore we use a novel experimental approach to determine the oil relative permeabilities below the critical gas saturation. A mathematical model has been created to reconstruct both the gas and the oil relative permeabilities for the whole saturation range. Laboratory observations have shown that in low-permeable rocks the relative permeabilities may strongly decrease, even when the amount of the liberated gas is small. The goal of this work is to verify, on a specific example, whether the designed model for the relative permeabilities may explain the observed production behavior for a low-permeable chalk reservoir in the North Sea. We perform a sensitivity study using the parameters of relative permeabilities and analyze the corresponding differences in well productivities. A reasonably good match of <10% can be obtained to the historical well production data. A few cases where the match was not satisfactory (14% to 65%) are also analyzed, and the difference is attributed to the imprecise fluid model. The developed experimental and modeling methodology may be applied to other reservoirs developed by the solution gas drive mechanism. [ABSTRACT FROM AUTHOR]

Bubble point pressure and gas solubility are considered vital pressure-volume-temperature properties of crude oil samples as both play a significant role in reservoir and production engineering calculations. These two fluid oil properties can be measured experimentally or using mathematical correlations, the experimental methods are time consuming and expensive, although they give a reliable result. Therefore, using mathematical correlations can be as an alternative way, however, existing correlation having number of limitations. Hence, this study presents a novel numerical model based on artificial neural network (ANN) model and universal mathematical correlation to forecast bubble point pressure and gas solubility. The artificial neural network model based on back-propagation learning algorithm and sigmoid function with numerous inputs include API gravity, reservoir temperature, and gas specific gravity. The ANN model is developed and validated by utilizing more than 450 data points collected from numerous fields located worldwide with various reservoir characterization. In this study, the bubble point pressure is estimated first and then used to forecast gas solubility based on the calculated correlation coefficient. The results of this study concluded that in order to optimize the ANN model, collected data must to be distributed as follows; 65% for training, 20% for testing and 15% for the validation processes with R2 of 0.988 and average absolute percent relative error (AAPRE) =5.56% for the bubble point pressure and 4.5% for the gas solubility. A comparison study is performed between the new ANN extracted correlation and other well-known models (Standing, Petrosky and Frashad, McCain, Vasquez and Beggs, Marhoun, Glaso, Dokla, and Lasater correlations) to show the robustness of the presented correlation. The results show that the presented correlation has the ability to predict bubble point pressure and gas solubility precisely with lowest AAPRE compared to other models.

The development of porous ceramic screens with high chemical stability, low density, and thermal conductivity can lead to promising screen channel liquid acquisition devices (SC-LADs) for propellant management under microgravity conditions in the future. Therefore, SiOC screens with aligned pores were fabricated via freeze-casting and applied as a SC-LAD. The pore window sizes and open porosity varied from 6 µm to 43 µm and 65% or 79%, depending on the freezing temperature or the solid loading, respectively. The pore window size distributions and bubble point tests indicate crack-free screens. On the one hand, SC-LADs with an open porosity of 79% removed gas-free liquid up to a volumetric flow rate of 4 mL s−1. On the other hand, SC-LADs with an open porosity of 65% were limited to 2 mL s−1 as the pressure drop across these screens was relatively higher. SC-LADs with the same open porosity but smaller pore window sizes showed a higher pressure drop across the screen and bubble ingestion at higher values of effective screen area when increasing the applied removal volumetric flow rate. The removed liquid from the SC-LADs was particle-free, thus representing a potential for applications in a harsh chemical environment or broad-range temperatures.

Bubble point tests are widely used for assessing the integrity of sterilizing-grade membrane cartridge filters. While many authors have considered the limitations of bubble point tests as applied to cartridge filters, the level of bacterial retention assurance provided by this test as conducted with automated integrity testers (AITs) has not, until now, been quantified. Contrary to the notion that filter leaks result in a depressed bubble point, it was shown that the bubble point as reported by AITs was insensitive to defect size up until the point where the AIT either determined a gross leak failure or was not able to return a valid result. For the three AITs used in this study, the minimum laser hole defect diameter in 10-inch (25.4 cm) sterilizing-grade cartridge filters that resulted in a failing bubble point test was between about 30 and 60 µm, depending on the filter type and test conditions. These defect sizes were associated with bacterial log reduction values in the 4.0 to 4.5 range. This study supports the generally recommended practice of pairing the bubble point test (which does confirm proper pore size rating) with a complementary gas–liquid diffusion test (better suited for detecting defects) to achieve a more comprehensive assessment of filter integrity.

Production from the North Sea reservoirs often results in a pressure decrease below the bubble point. The gas is liberated from oil, in the form of bubbles or as a continuous flowing phase. In such cases, the two phases, gas and oil, flow in the reservoir simultaneously, and the flow is governed by the values of relative permeabilities. Traditional core flooding in low permeability rocks is challenging, therefore we use a novel experimental approach to determine the oil relative permeabilities below the critical gas saturation. A mathematical model has been created to reconstruct both the gas and the oil relative permeabilities for the whole saturation range. Laboratory observations have shown that in low-permeable rocks the relative permeabilities may strongly decrease, even when the amount of the liberated gas is small. The goal of this work is to verify, on a specific example, whether the designed model for the relative permeabilities may explain the observed production behavior for a low-permeable chalk reservoir in the North Sea. We perform a sensitivity study using the parameters of relative permeabilities and analyze the corresponding differences in well productivities. A reasonably good match of

Phase separation in space is critical for gas-free propellant supply, life support systems, refueling of spacecraft in low earth orbit (LEO), and for deep space exploration missions. In the absence of gravity, the stability of the liquid-gas interface depends on capillary forces. High liquid flow rates, sudden accelerations, and vibrational disturbances can cause the free surface of the liquid to collapse, which results in the ingestion of gas. Propellant tanks may have screen channel liquid acquisition devices (SCLADs) to position and maintain a gas-free propellant supply to the outlet. A saturated porous screen permits liquid to pass through but acts as a barrier to the gas. We investigated phase separation in porous media integrated capillary channels during parabolic flights (33rd DLR parabolic flight campaign in March 2019). An open side of a rectangular channel was covered with a dutch twill weave 200×1400. The liquid was ingested into the channel from its surroundings by establishing a differential pressure across the screen section. The gas-phase was blocked during the liquid withdrawal. We could show that the gas breakthrough occurs when the pressure difference across the screen exceeds the bubble point pressure. The experimental results showed good agreement with correlations from literature. [ABSTRACT FROM AUTHOR]

Copyright of Association of Arab Universities Journal of Engineering Sciences (JAARU) is the property of Association of Arab Universities and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reservoir fluid properties such as oil formation volume factor and solution gas oil ratio are of primary importance in reservoir engineering computations such as material balance calculation, while viscosity of crude oil and density required for controlling the oil’s flow through porous media and pipes and play an essential role in production engineering and in well problem analysis. This study evaluates all available published oil formation volume factor and gas oil ratio empirical correlations against a set of Yemeni PVT data. The study presents new tuned empirical correlations for Yemeni crude oils for oil formation volume factor and solution gas oil ratio at bubble point pressure based on huge Yemeni data sets. Excel program techniques such as solver function are also used for predicting oil formation volume factor and solution gas oil ratio at bubble point pressure. To compare the performance and accuracy of the new reservoir fluid properties correlations, statistical error analysis is performed. The statistical analysis results indicate that, the new tuned oil formation volume factor and solution gas oil ratio correlations outperforms the most common empirical correlations with least average absolute error, least standard deviation and highest correlation coefficient. [ABSTRACT FROM AUTHOR]

Abstract This paper develops ensemble machine learning model for the prediction of dead oil, saturated and undersaturated viscosities. Easily acquired field data have been used as the input parameters for the machine learning process. Different functional forms for each property have been considered in the simulation. Prediction performance of the ensemble model is better than the compared commonly used correlations based on the error statistical analysis. This work also gives insight into the reliability and performance of different functional forms that have been used in the literature to formulate these viscosities. As the improved predictions of viscosity are always craved for, the developed ensemble support vector regression models could potentially replace the empirical correlation for viscosity prediction.

Metal screens are commonly used as components for fluid handling in spacecraft and rocket tank designs. In most cases the screen performs a passive separation of the gaseous from the liquid propellant phase. This means that the liquid is able to flow through the screen, causing a flow through screen pressure drop, while the gaseous phase is blocked due to the pressure jump across a curved liquid-gas interphase at the small screen pores. As long as the flow through screen pressure drop is smaller than the bubble point pressure, phase separation is possible and allows the provision of gas-free liquid for the spacecraft or rocket engine. The opposite, the separation of the liquid from the gaseous propellant phase, is more challenging. Liquid-gas phase separation means that the gaseous phase is allowed to enter the phase separation device while the liquid phase is blocked. The separation of the liquid from the gas is possible due to a double screen element, as the work of Conrath et al. (Int. J. Multiphase Flow 50, 1–15, 2013) and Behruzi et al. (2013) has shown for storable liquids in Earth's gravity and microgravity as well as for cryogenic liquids in Earth's gravity. The liquid-gas phase separation of cryogenic liquids in microgravity however has not been investigated yet. Therefore, an experimental campaign consisting of six drop tests in microgravity using the drop tower at the University of Bremen, has been conducted. The experimental results confirm predicted governing physical phenomena and give evidence about further fluid mechanical and thermodynamical effects. [ABSTRACT FROM AUTHOR]

• A new laboratory experiment is presented for teaching petroleum fluids. • The new visual cell is simple, low-cost, and easy to use for educational purposes. • Students learn how petroleum fluids are tested and how the data are used. • Students become familiar with an equation of state. • Course surveys indicate positive responses about the new experiment. This paper presents a new way to conduct an educational experiment for bubble-point determination of a hydrocarbon mixture. The visual fluid cell newly designed for educational purposes made it possible to teach bubble-point determination safely at low cost within a few hours for groups of students in a laboratory class. The educational experiment developed has been successfully implemented for three semesters at the authors' institution with positive responses from a vast majority of the students. It is hoped that this paper helps other interested instructors enhance students' learning experience in the subject of fluid properties. [ABSTRACT FROM AUTHOR]

The most crucial aspect in screen channel liquid acquisition device (LAD) design is the bubble point pressure (Δ P BP). Historically, results have shown that cryogenic liquid nitrogen (L N 2) Δ P BP values can be increased when using helium (GHe) pressurant and decreased when using gaseous nitrogen (G N 2) pressurant due to evaporative cooling and condensation heating of the liquid-vapor interface within the screen, respectively. Historical results show a reduction in Δ P BP performance when using warm pressurant, regardless of pressurant gas type. This paper presents warm pressurant Δ P BP tests in L N 2 using both GHe and G N 2 with pressurant bulk gas temperatures T GB between 77 − 160 K for 14 screen types, focusing on coarser meshes. Results from this study show a degradation in GHe Δ P BP but no degradation in G N 2 Δ P BP at elevated T GB , the latter of which contradicts historical trends. To help explain these results and to provide a level of physical background to the warm pressurant Δ P BP experiments, a noncondensable pressurant sweat cooling heat and mass transfer model is developed as part of this study. Based on current and historical results, it is concluded that the flow velocities on the gas side of the screen could degrade Δ P BP significantly, especially when warm pressurant is used. [ABSTRACT FROM AUTHOR]

This paper develops ensemble machine learning model for the prediction of dead oil, saturated and undersaturated viscosities. Easily acquired field data have been used as the input parameters for the machine learning process. Different functional forms for each property have been considered in the simulation. Prediction performance of the ensemble model is better than the compared commonly used correlations based on the error statistical analysis. This work also gives insight into the reliability and performance of different functional forms that have been used in the literature to formulate these viscosities. As the improved predictions of viscosity are always craved for, the developed ensemble support vector regression models could potentially replace the empirical correlation for viscosity prediction. [ABSTRACT FROM AUTHOR]

Copyright of Al-Andalus Journal for Applied Sciences is the property of Alandalus University for Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The phase-behavior data are presented for three kinds of commercial polymer-bonded explosive (PBX) elastomers in dimethyl ether (DME). Ethylene- co-vinyl acetate (with vinyl acetate contents of 40 % (EVA40) and 60 % by mass (EVA60)) and alkyl acrylate (ACM) copolymers were used as the PBX elastomers. For each elastomer/DME system, the cloud- and/or bubble-point (phase-boundary) pressures were measured as a function of temperature and elastomer composition using a high-pressure phase-equilibrium apparatus equipped with a variable-volume view cell. For the EVA60/DME system, the cloud-point pressure increased as the EVA60 composition increased. The ACM elastomer was readily soluble in saturated liquid-state DME at most temperature and elastomer composition ranges. [ABSTRACT FROM AUTHOR]

• Equations of State (EoS) in commercial property packages exhibit poor performance in VLE calculations of (CO 2 + H 2) mixtures. • Experimental data with up to 5% mol content of H 2 was used to tune EoS implemented in a commercial simulator. • New BIPs are obtained for various EoS implemented in Multiflash. • Tuned EoS shows consistent performance in phase envelope calculation. However, cubic EoS slightly performs better. • GERG-2008 significantly outperforms cubic EoS (even if volume shifts factors are used) in liquid densities. The impact of impurities in the physical properties of CO 2 is now widely acknowledged by industry. In particular, the presence of H 2 in CO 2 mixtures has a significant effect on the saturation pressure (bubble point) and bulk (liquid) density. Both physical properties are key in the many engineering tasks, for example, in calculating the closed-in tubing head pressure of an injection well or in defining operating pressures to avoid two-phase region in transport systems. If there are large uncertainties in the estimated properties, then, significant design margins will be required making the system less cost-effective. The reliability of Equations of State (EoS) implemented in property packages used in industry is limited to the availability and quality of the experimental data that was used to calibrate the model. For the pair CO 2 H 2 , there is lack of validation at conditions of CCS systems. Thus, the performance of EoS is unsatisfactory for many CO 2 H 2 mixtures. An additional complication is that there is large discrepancy not only between models but also between the 'same' model implemented across different platforms. For the practitioner, this poses quite a conundrum: 'What EoS and package should be used?'. In this work, an attempt to homogenize various EoS implemented in commercial software is presented. To calibrate the models, a subset of available of experimental data with content of up to 5%mol of H 2 is used. A different subset of data is used to assess the performance of the fitted models. In the parameter estimation problem, the EoS are tuned via Binary Interaction Parameters (BIPs) or departure parameters. To improve liquid density calculations, an additional step is used to regress cubic EoS via volume shift parameters. The resulting optimized EoS can be readily available in commercial simulators, and it is hope that they will be part of a growing databank/toolbox for engineering design activities of CCS systems. [ABSTRACT FROM AUTHOR]