Joule-Thomson Effect Research Articles

Einstein-AdS Gravity Coupled to Nonlinear Electrodynamics, Magnetic Black Holes, Thermodynamics in an Extended Phase Space and Joule–Thomson Expansion

We studied Einstein’s gravity with negative cosmological constant coupled to nonlinear electrodynamics proposed earlier. The metric and mass functions and corrections to the Reissner–Nordström solution are obtained. Black hole solutions can have one or two horizons. Thermodynamics and phase transitions of magnetically charged black holes in Anti-de Sitter spacetime are investigated. The first law of black hole thermodynamics is formulated and the generalized Smarr relation is proofed. By calculating the Gibbs free energy and heat capacity we study the black hole stability. Zero-order (reentrant), first-order, and second-order phase transitions are analyzed. The Joule–Thomson expansion is considered, showing the cooling and heating phase transitions. It was shown that the principles of causality and unitarity are satisfied in the model under consideration.

Heat Production Performance from an Enhanced Geothermal System (EGS) Using CO2 as the Working Fluid

CO2-based enhanced geothermal systems (CO2-EGS) are greatly attractive in geothermal energy production due to their high flow rates and the additional benefit of CO2 geological storage. In this work, a CO2-EGS model is built based on the available geological data in the Gonghe Basin, Northwest China. In our model, the wellbore flow is considered and coupled with a geothermal reservoir to better simulate the complex CO2 flow and heat production behavior. Based on the fractured geothermal reservoir at depths between 2900 m and 3300 m, the long-term (30-year) heat production performance is predicted using CO2 as the working fluid with fixed wellhead pressure. The results indicate that the proposed CO2-EGS will obtain an ascending heat extraction rate in the first 9 years, followed by a slight decrease in the following 21 years. Due to the significant natural convection of CO2 (e.g., low viscosity and density) in the geothermal reservoir, the mass production rate of the CO2-EGS will reach 150 kg/s. The heat extraction rates will be greater than 32 MW throughout the 30-year production period, showing a significant production performance. However, the Joule–Thomson effect in the wellbore will result in a drastic decrease in production temperature (e.g., a 62.6 °C decrease in the production well). This means that the pre-optimization analyses and physical material treatments are required during geothermal production using CO2 as the working fluid.

Integration of subsurface dynamic coupled modelling and monitoring technologies for CCS: examples from existing projects


 Introduction
 Host rock injectivity and storage complex integrity (containment) for CO2 sequestration are critical factors to ensure that capacity targets are met while preventing CO2 leakage over time and confirm permanent storage.
 
 Figure 1 sketches the typical CO2 injectivity problem. Evaluating injectivity, capacity and containment requires assessing key phenomena such as: seal and faults capillary controls, non-isothermal reactive flow, geomechanical failure induced in the seal, along faults and/or fractures and in the vicinity of the wells. Additional analyses will also be needed to evaluate the completion integrity of the wells (injectors, monitoring and existing wells) under variable load conditions in terms of pressure, temperature and chemistry. The listed phenomena, and their likely effects, are analysed by means of dynamic coupled modelling, considering co-existing (geo)mechanical and dynamic flow simulations. Therefore, coupled modelling improves the risk analysis allowing to evaluate the Thermo-Hydro-Mechanical-Chemical (THMC) processes associated to CO2 injection.
 Analyses
 In this presentation we will provide some examples of integration of subsurface dynamic coupled modelling and monitoring technologies for CCS. Some of these examples are derived from existing projects.
 
 Injectivity impairment during CO2 injection is a well-known issue often observed at well and field scale (e.g. Snøhvit, Ketzin, Decatur projects [1], [2]). Loss of injectivity is governed by the interactions between CO2-brine phase behavior, CO2-solid phase (rock) behavior, salt precipitation, multi-phase flow. Characterizing zonal injectivity and developing mitigation strategies will be therefore important for project success. Figure 2 (left and center) shows an example of time-lapse CO2 saturation evolution during injection and consecutive non-isothermal processes associated to Joule-Thompson effect (H2O vaporization, cooling and induced salt precipitation due to dry-out). Temperature and pressure changes can lead to near wellbore failure (thermal and pressure induced fracturing) impacting injection performance due to near wellbore fracturing and consecutive permeability changes (Figure 2 right).
 To close the evaluation loop, the integrated subsurface characterization workflow is completed by measurements to image the subsurface before and after CO2 injection. This provides essential insights into the storage complex quality before injection and effective monitoring during injection and permanent storage, tracking the position of the CO2 pressure and concentration plumes, assessing surface heave, and detecting any risks or potential leakage paths. There is a tight link between subsurface dynamic coupled modelling and existing monitoring technologies. This link expands the well-known MMV (Measurement, Monitoring and Verification) process into a more integrated 3MV process (Modelling, Measurement, Monitoring and Verification), opening to the definition of a subsurface digital twin supporting successful CCS operations. We will briefly introduce methods and technologies enabling the subsurface dynamic modelling and monitoring of CO2 injection and storage. Seismic and borehole petrophysical and geophysical measurements for initial subsurface characterization and consecutive monitoring will be described.

Способы расчета нагрева топлива при впрыскивании в дизельных двигателях с давлением до 400 МПа

The study is driven by the trend of the rapidly growing injection pressure in diesel and gasoline engines with fuel injection into the combustion chamber. Experimental results were obtained by pouring fuel through a model nozzle and through the electrohydraulic diesel injectors. The paper describes reasons for the fuel significant heating at the injection and proposes its mathematical substantiation. For different tasks and fuels, three methods for the heating calculation during fuel injection at the ultra-high pressures were demonstrated. It was revealed that most important was fuel heating by the Joule-Thomson effect in the injector nozzle. Due to action of several heat release factors, fuel temperature could reach 240...260°C at the injection pressure of 350...400 MPa. The paper proposes most convenient relationships for computational analysis of the thermal conditions of the fuel supply process. Fuel heating assessment makes it possible to find the boundary conditions for calculating the intra-cylinder processes and the fuel outflow crisis at the ultra-high pressures.

Thermo-economic evaluations of novel dual-heater regenerative organic flash cycle (DROFC)

Organic Flash Cycle (OFC) is a promising waste heat utilization technique for low and medium temperature. However, throttling exergy loss in the flash and throttling processes substantially reduces the efficiency of basic organic flash cycle (BOFC). The regenerative organic flash cycle (ROFC) can avoid the exergy loss in the throttling process and enhance the thermodynamic performance of OFC. This paper proposes a novel dual-heater regenerative organic flash cycle (DROFC), which can obtain more power output by reducing the flash process exergy loss and eliminating the mixer exergy loss in ROFC. The thermo-economic performance of DROFC was compared with BOFC and ROFC to evaluate its application potential. Eight low-GWP pure organic fluids were selected and the heat sources were 100–200 °C. Results indicate that DROFC could produce more net power output than BOFC and ROFC with a lower specific investment cost. Specifically, with R600 as an example, the maximum net power output percentage gain of DROFC is 41.19% and 29.09%, respectively. DROFC is more suitable for application scenarios where the heat source temperature exceeds the critical temperature of organic fluid. To balance the net power output and levelized cost of electricity, Hydrocarbons with a high critical temperature are appropriate for DROFC.

Edge Bonding Voids Management Using Humid Helium Bonding Atmosphere

Hydrophilic direct wafer bonding involves two types of bonding voids: classical voids caused by contamination or surface topography, and edge voids resulting from the bonding wave dynamics. The adiabatic expansion of the bonding wave at the wafer edge can lead to condensation of humidity and the formation of small water droplets, resulting in bonding defects even without contamination. These defects persist even under dry gas conditions. Two methods are used to address this issue. The first is vacuum bonding (<0.1 mbar), and the second involves using gases with a negative Joule-Thomson coefficient, such as helium. Helium is preferred due to its low coefficient and cost-effectiveness. However, bonding under pure helium results in lower adhesion and adherence energy. In this study, humid helium, generated using a dedicated humidifier, is used to evaluate the adhesion energy and adherence of standard Si/SiO2 bonding.

Effects of filling strategies on hydrogen refueling performance

In order to ensure the safety of hydrogen refueling systems and fuel cell vehicles under various filling conditions, the filling parameters are usually set very conservatively, leading to waste energy consumption and investment. The lumped parameter hydrogen gas model and one-dimension tank wall model of the hydrogen filling process previously proposed by our team were extended and improved to the entire hydrogen refueling system by considering the Joule-Thomson effect, kinetic energy and using a more accurate model of the heat transfer coefficients between the inner tank wall and hydrogen gas and between the outer tank wall and ambient. Based on our validated model, the effects of constant and two-stage average pressure ramp rates (APRRs) and precooling/inlet temperatures on refueling performances were investigated, respectively. Compared with the optimal filling strategy of the reference paper, where a constant APRR is the best, our two-stage APRRs can further reduce the cooling power for various inlet temperatures without increasing the cooling energy. For example, maximum cooling power can be reduced by 23.8% at the inlet temperature of −20 °C. Compared with the previous research result obtained using a constant inlet temperature solved by the analytical solution, the two-stage inlet temperatures can further reduce the cooling power by 16.3% at an APRR of 0.428 MPa/s without increasing the cooling energy.

METHOD OF CREATION AND ADAPTATION THERMOHYDRODYNAMIC MODELS OF DEVELOPMENT TURONIAN GAS DEPOSITS BASED ON HYDRODYNAMIC MODELS OF ISOTHERMAL FILTRATION FOR PREDICTION THERMOBARIC CONDITIONS OF HYDROCARBON RAW MATERIALS DURING THEIR DEVELOPMENT

The current high rates of exploration and involvement in thedevelopment of hard-to-recover natural gas reserves associated with theTuronian deposits require an increase in the level of digitalization ofdevelopment, including the development of means to ensure integratedintegrated design and forecasting of development processes. The articledescribes the developed methodology for the creation and adaptation ofthermohydrodynamic models for the development of Turonian gasdeposits based on hydrodynamic models of isothermal filtration to predictthe thermobaric conditions of hydrocarbon raw materials duringtheir development. The main advantages of the thermohydrodynamicmodel include the ability to use it to solve applied and practical tasks forthe design of development and monitoring of its implementation. Inparticular, it is possible to assess the impact of the hydrate formationprocess on changes in the productivity of producing wells, develop proposalsfor optimizing the applied methods of gas-dynamic studies andinterpreting data taking into account the risk of hydrate precipitation inunacceptable operating modes, justify the maximum and maximumdepressions during the entire development period for existing and projectwells to control the thermobaric conditions of hydrate formation andprevent the formation of hydrates in well completion system. Taking intoaccount the urgency of the issue of import substitution, the developedmethodology was implemented and tested using the domestic tNavigatorhydrodynamic simulator. The stage of analysis of initial data (fluid data,core research data, geological and field data on wells) is described, thebasic concepts of thermohydrodynamic modeling of development (thermalconductivity, Fourier law, enthalpy, internal energy, entropy, Joule-Thomson effect) are given, the stage of integration of the thermal optioninto the isothermal filtration model is described, approaches are presentedto adapt the thermohydrodynamic model to the actual geologicaland field data, the evaluation and analysis of the results obtained werecarried out.

Weak periodic solutions of a parabolic–elliptic system with Joule–Thomson effect

Weak periodic solutions of a parabolic–elliptic system with Joule–Thomson effect

Experimental investigation on the stability of gas hydrates under near-wellbore conditions during CO2 injection for geologic carbon storage

Carbon capture and storage (CCS) is one of the key technologies in reducing the CO2 concentration in the atmosphere. The injection of CO2 into depleted reservoirs, saline aquifers and salt caverns to permanently store it in geologic formations is called geologic carbon storage (GCS).In this paper, the focus is set on the possible hydrate formation due to cooling while injecting CO2 in depleted gas reservoirs (DGR) for GCS, in which the reservoir pressure is so low that the pressure difference between injected fluid and reservoir at sand face can result in operational challenges. The temperature reduction due to abrupt pressure reduction near the wellbore, caused by the so-called Joule-Thompson (J-T) effect, plays a crucial role in the design of CO2 injection. Detection of hydrate in the early stage (equilibrium point) as well as the metastable zone lead to avoid interruption of the CO2 injection process due to plugging effects in the near wellbore area.Therefore, this study focused on the formation and equilibrium conditions as well as estimation of the metastable zone of CO2 hydrates formed in brine of different concentrations and at different CO2 phases. An experimental setup was build up and presented. Moreover, the main component of gas reservoirs, CH4, was taken into account and hydrates from mixed gas spheres were investigated. Also N2 and O2 were added to CO2 in small amounts because these gases can be introduced from the surface CO2 sequestration process as impurities. The studies were carried out in a temperature range of (266–284) K and in a pressure range of about (2.5–9.0) MPa adapted from the project field specifications. A good agreement of the equilibrium data with the predicted date from HYDOFF program by Sloan in all cases studied was found. The novelty of the present study is the investigation of the gas hydrate formation points (at cooling rates of 0.45 K/min) to estimate the metastable zone of gas hydrate. For all tests, the metastable range was quantified. Possible subcooling before gas hydrate formation was found to be between (1.4–9.0) K. This is an important outcome of the study as this implies that CO2 injection without gas hydrate forming seems to be still possible although operating conditions are already submerged into the GHSZ.Additionally, it was observed that the salinity of the water phase has significantly higher influence on the gas hydrate formation and dissociation than the components of gas mixture. Nevertheless, gas impurities (N2, O2) act as retardant in contrast to CH4 which doesn't affect the CO2 hydrate stability zone significantly.

Leakage Monitoring and Quantitative Prediction Model of Injection–Production String in an Underground Gas Storage Salt Cavern

The leakage of the injection–production string is one of the important hidden dangers for the safe and efficient operation of underground salt cavern gas storage. Although distributed fiber optic temperature measurement system (DTS) can accurately locate the position of the string leakage port, how to establish the quantitative relationship between the temperature difference and leakage rate of the leakage port still needs further exploration. This paper proposes a new quantitative prediction model based on a DTS for the leakage monitoring of the injection–production string of salt cavern gas storage. The model takes into account the gas’s physical parameters, unstable temperature conditions, and the Joule–Thomson effect. In order to verify the accuracy of the model, a simulation experiment of string leakage based on a DTS was carried out. The test results show that the relative deviation between the predicted leakage rate and the measured value is less than 5% compared with the calculated value. When the leakage rate drops to 0.16 m3/h and the temperature range is less than 0.5 °C, it is difficult to accurately monitor the DTS. The results of this study help to improve the early warning time of underground salt cavern gas storage string leakage.

4[formula omitted] AdS Einstein–Gauss–Bonnet black hole endowed with Lorentzian noncommutativity: [formula omitted] criticality, Joule–Thomson expansion, and shadow

In this article, we get a static, spherically symmetric 4D-AdS EGB black hole inspired by noncommutative geometry, where noncommutativity is expressed by a Lorentzian distribution. The noncommutativity correction has changed the relevant thermodynamic quantities. The cosmological constant Λ is interpreted as a dynamical pressure, and the noncommutative parameter Θ is treated as a thermodynamic variable to keep the first thermodynamic law and the Smarr formula in place. Our solution’s P−v criticality was investigated in the extended phase space, where the large/small black hole phase transition arises for the noncommutative 4D-AdS EGB black hole. That is, the noncommutativity parameter influences the phase transition as well as the critical pressure, horizon radius, and temperature; as a result, the critical ratio is also influenced and does not yet remain universal, as in the Van der Waals systems. The Joule–Thomson expansion has been studied in extended phase space. We acquired the inversion points (Pi,Ti) as a function of Θ, which allowed us to analyze the isenthalpic and inversion curves in the T−P plane and demonstrate the cooling and heating zones. In addition, it has been shown that the shadow radius is reduced when we increase the noncommutativity parameter, as is the peak of the associated energy emission rate, which decreases with the rise of the parameter Θ.

How the cylinder initial conditions affect the HCNG refuelling process - A thermodynamic analysis to determine the most effective filling parameters

The hydrogen compressed natural gas (HCNG) blends play a key role in the European Hydrogen Roadmap targets achievement. The HCNG refuelling stations can be built up by upgrading the existing compressed natural gas stations. This work investigates the thermodynamic of HCNG refuelling processes to determine the impact on gas temperature due to the Joule-Thomson effect, heat transfer through the cylinder wall, the kinetic energy conversion in internal energy, and compression contribution during the fast fill-up. Specifically, the vehicle tank initial conditions and the refuelling parameters have been analysed, evaluating how they affect the final refuelling temperatures, filled mass, relative states of charge, and refuelling times. With an average pressure ramp rate of 0.18 MPa/s, at initial cylinder conditions of 10 °C and 9 MPa, the 0.065 m3 and 0.15 m3 tanks reach a SOC of 93.83% and 65.32% and final temperature of 82.5 °C and 44.5 °C, respectively.

Einstein–AdS gravity coupled to modified arctan-electrodynamics, magnetic black hole thermodynamics and Joule–Thomson expansion

The metric and mass functions of Einstein–AdS gravity coupled to modified arctan- electrodynamics (proposed here) are obtained. We find corrections to the Reissner–Nordström solution. It is demonstrated that if the Schwarzschild mass is zero and as r→0 the asymptotic has the de Sitter core. Thermodynamics of magnetically charged black holes in Anti-de Sitter spacetime in an extended phase space, where the cosmological constant is treated as a pressure and the black hole mass is considered as the chemical enthalpy, is studied. It is shown that the black hole thermodynamics mimics the Van der Waals liquid–gas thermodynamics. The magnetic potential and vacuum polarization are calculated. We formulate the first law of black hole thermodynamics and proof that the generalized Smarr relation holds. The critical specific volume, temperature and pressure are evaluated and the critical behaviour of black holes is investigated. We calculate and study the Gibbs free energy and show that phase transitions take place. The local stability are studied by calculating the heat capacity. The black hole Joule–Thomson adiabatic expansion, cooling and heating phase transitions are investigated. We evaluate the Joule–Thomson coefficient and the inversion temperature.

Improved temperature distribution upon varying gas producing channel in gas hydrate reservoir: Insights from the Joule-Thomson effect

The gas production from marine gas hydrate has always been plagued by low productivity; the complex geological environment poses a significant obstacle to its commercialization. Horizontal wells are thus getting increasing attention due to their advantages in facilitating pressure propagation. Here a pre-embedded dual horizontal well was used to probe its effects in the local temperature distribution and gas production behavior. By doubling the number of boreholes, the flow channels of gas were increased enlarging the decomposition zone. Specifically, this was found to raise the reservoir temperature from −1 °C in a single well to approximately 0 °C. The temperature decline was more moderate due to a weakened Joule-Thomson effect. Consequently, almost 90% of the cumulative gas yield was produced before the lowest temperature occurred, compared to ∼30% in the single vertical well case. This indicates that the gas production from a dual well case was proceeding at a relatively higher temperature, potentially benefitting an enhanced gas production efficiency. An enlarged depressurization region was thus suggested in the field test for a controlled temperature decline to make more use of the sensible heat of the reservoir.

Insight into the effects of hydrogen on inside-valve flow and Joule-Thomson characteristics of hydrogen-blended natural gas: A numerical study

Blending hydrogen into natural gas is a feasible way to transport hydrogen via natural gas pipelines. In hydrogen-blended natural gas (HBNG) pipelines, choking is an essential process that concerns safety issues like condensation and hydrate formation inside valves and the Joule-Thomson (J-T) characteristics like temperature drops, isenthalpic curve (IC), Joule-Thomson coefficient (JTC). However, these two aspects of HBNG differ from those of natural gas, and the differences in inside-valve flow remain unknown, and those in J-T characteristics remain less clear. Given the incapability of the isenthalpic model in obtaining inside-valve flow fields, we conduct a comprehensive study on the effects of hydrogen on inside-valve flow and J-T characteristics of HBNG by combining the computational fluid dynamics (CFD) model and the isenthalpic model. We develop a numerical model by coupling the isenthalpic equations, the conservation equations, the k-ω turbulence equations, and the species transport equations. For the first time, we discuss the effects of hydrogen on the temperature, pressure, and velocity fields of HBNG and evaluate the risks of p-T curves entering vapor-liquid equilibrium and hydrate formation regions. Then, we analyze the effects of hydrogen on ICs and JTCs. Results indicate that with increasing hydrogen mole fraction (HMF), the temperature along the center line rise, the minimum temperature increases roughly linearly, and the corresponding positions shift to the throat in a rough linear law. The JTCs of HBNG roughly linearly decrease with increasing HMF from 0% to 30%.

The New Ice Age of Musculoskeletal Intervention: Role of Percutaneous Cryoablation in Bone and Soft Tissue Tumors.

In the rapidly evolving field of interventional oncology, minimally invasive methods, including CT-guided cryoablation, play an increasingly important role in tumor treatment, notably in bone and soft tissue cancers. Cryoablation works using compressed gas-filled probes to freeze tumor cells to temperatures below -20 °C, exploiting the Joule-Thompson effect. This cooling causes cell destruction by forming intracellular ice crystals and disrupting blood flow through endothelial cell damage, leading to local ischemia and devascularization. Coupling this with CT technology enables precise tumor targeting, preserving healthy surrounding tissues and decreasing postoperative complications. This review reports the most important literature on CT-guided cryoablation's application in musculoskeletal oncology, including sarcoma, bone metastases, and bone and soft tissue benign primary tumors, reporting on the success rate, recurrence rate, complications, and technical aspects to maximize success for cryoablation in the musculoskeletal system.

Magnetic black holes within Einstein–AdS gravity coupled to nonlinear electrodynamics, extended phase space thermodynamics and Joule–Thomson expansion

Einstein’s gravity in Anti-de Sitter space coupled to nonlinear electrodynamics is studied. We analyse the metric, mass functions, and corrections to the Reissner–Nordström solution. Magnetic black holes thermodynamics in extended phase space is investigated. We formulate the first law of black hole thermodynamics showing that the generalized Smarr relation holds. The black hole stability is studied by evaluating the Gibbs free energy and heat capacity. To study the cooling and heating phase transitions of black holes, we consider the Joule–Thomson isenthalpic expansion. The Joule–Thomson coefficient and the inversion temperature are calculated.

Ultra-long-distance transport of supercritical natural gas (SNG) at very-high mass flow rates via pipelines through land, underground, water bodies, and ocean

A detailed study of SNG transport using a computational model that accounts for compressibility and Joule-Thomson effects is presented, for the first time. It shows that the transport distance and mass flow rate of supercritical natural gas (SNG) - above the cricondenbar and cricondentherm, and beyond the anomalous state - can exceed far beyond that achieved or proposed under high pressure, dense phase conditions, thus far. As an example, SNG (average composition of USA/Canada gas), at 800 kg/s can travel, without recompression, to 4801 km. It is revealed that the pressure-drop and pumping power per unit length decrease asymptotically as the inlet pressure increases beyond 20 MPa; orders-of-magnitude lower than that at low pressures. The increase in inlet pressure, pipe diameter, and/or heat conductance of the pipe wall increases the distance travelled by SNG whereas the increase in mass flow rate and surrounding temperature has a negative effect, including the strengthening of Joule-Thomson cooling near the exit. SNG pipelines at ocean bottom offer many advantages, including shorter distances, isothermal flows (∼4 °C), and balance between the outer and inner pressures. Also, SNG delivery at 6 MPa can allow regional distribution without immediate recompression. SNG pipelines therefore offer enormous possibilities of energy-efficient transport of natural gas to far-distant intra- and inter-continental destinations, not feasible thus far, which is urgently needed for uninterrupted supply of natural gas and worldwide energy security.

Experimental Investigation and Thermophysics Analysis of Joule Thomson Cooler Applicable to Infrared Imaging

Recuperative type of heat exchanger (H-E) based miniature Joule-Thomson (J-T) cooler operated in the steady-state condition is employed extensively in applications towards infrared detectors cooling, thermal imaging cameras, and homing guidance devices in a wide variety of defence projectile systems. In this study, a theoretical thermal design of recuperative H-E for determining a viable geometry using iterative methodology is discussed. A steady-state numerical analysis for the developed geometrical model of the H-E is also reported, along with the experimental studies for typical operating conditions. A custom numerical code using the Runge-Kutta method has been developed in MATLAB, and the results from the code compared with predictions of COMSOL multi-physics are in good agreement. Further, results have been validated proving the efficacy of the theoretical model and custom numerical code developed.