Pseudo-critical Temperature Research Articles

QCD with 2+1 flavors at the physical point in external chromomagnetic fields

We investigate full quantum chromodynamics (QCD) with (2+1)-flavor of highly improved staggered quarks fermions at the physical point in the presence of uniform Abelian chromomagnetic background fields. Our focus is to conduct an exploratory study on the renormalized light and strange chiral condensates around the pseudocritical temperature. We find that in the confined region the gauge system is subjected to the chromomagnetic catalysis that turns into the inverse catalysis in the high-temperature regime. We further observe that the chiral condensates are subjected to the so-called thermal hysteresis. Our estimate of the deconfinement temperature indicates that the critical temperature begins to decrease in the small field region, soon after it seems to saturate and finally increase with the strength of the chromomagnetic field. Published by the American Physical Society 2024

Thermal management for microelectronic chips under non-uniform heat flux with supercritical CO2

With the rapid growth of information technology and the evolution in the use of microelectronic chips, these components are facing major challenges of high heat dissipation and inhomogeneous heat flux. To address the hotspot issues, a combination of microchannel heat sinks (MCHS) with cavity-rib designs and supercritical fluids is a potential solution. This study compares the thermo-hydraulic properties of water and supercritical carbon dioxide (sCO2) under various boundary conditions and hotspot locations during non-uniform heating. The results showed that sCO2 can effectively improve temperature uniformity along the heat sink in the presence of hotspots as compared to water. Considering a mass flow rate of 600 kg/(m2·s), the inhomogeneity index of the basal temperature of sCO2 is found to be 0.24, significantly lower than 4.22 for water. This indicates that sCO2 eliminates hot spots by rapidly increasing specific heat capacity near the pseudo-critical temperature. Furthermore, it is noted that maintaining the operating temperature of sCO2 near the pseudo-critical temperature can increase the specific heat capacity of the fluid in a short time, in addition to reducing the corresponding density and viscosity. Consequently, the entropy generation rate of sCO2 under ideal conditions is 46.6 % of that of water. Therefore, the proposed combination of a microchannel of complex structure and sCO2 in this study is demonstrated to effectively reduce the influence of hot spots and improve the overall thermal performance of heat sinks.

Lattice study on finite density QC2D towards zero temperature

We investigate the phase structure and the equation of state (EoS) for dense two-color QCD (QC2D) at low temperature (T = 40 MeV, 324 lattice) for the purpose of extending our previous works [1, 2] at T = 80 MeV (164 lattice). Indeed, a rich phase structure below the pseudo-critical temperature Tc as a function of quark chemical potential μ has been revealed, but finite volume effects in a high-density regime sometimes cause a wrong understanding. Therefore, it is important to investigate the temperature dependence down to zero temperature with large-volume simulations. By performing 324 simulations, we obtain essentially similar results to the previous ones, but we are now allowed to get a fine understanding of the phase structure via the temperature dependence. Most importantly, we find that the hadronic-matter phase, which is composed of thermally excited hadrons, shrinks with decreasing temperature and that the diquark condensate scales as ⟨qq⟩ ∝ μ2 in the BCS phase, a property missing at T = 80 MeV. From careful analyses, furthermore, we confirm a tentative conclusion that the topological susceptibility is independent of μ. We also show the temperature dependence of the pressure, internal energy, and sound velocity as a function of μ. The pressure increases around the hadronic-superfluid phase transition more rapidly at the lower temperature, while the temperature dependence of the sound velocity is invisible. Breaking of the conformal bound is also confirmed thanks to the smaller statistical error.

Split of the pseudocritical temperatures of chiral and confinement-deconfinement transitions by a temperature gradient

Searching of the critical endpoint (CEP) of the phase transition of quantum chromodynamics (QCD) matter in experiments is of great interest. The temperature in the fireball at a collider is location dependent, however, most theoretical studies address the scenario of uniform temperature. In this work, the effect of temperature gradients is investigated using lattice QCD approach. We find that the temperature gradient catalyzes chiral symmetry breaking, meanwhile the temperature gradient increases the Polyakov loop in the confined phase but suppresses the Polyakov loop in the deconfined phase. Furthermore, the temperature gradient decreases the pseudocritical temperature of chiral transition but increases the pseudocritical temperature of the confine-deconfine transition. It is also found that the temperature gradient can drive the system away from the singularity, implying that the CEP in the T−μ plane may move in the direction of the first-order phase transition in the phase diagram due to the temperature gradient. Published by the American Physical Society 2024

Turbulent pipe flow and heat transfer of a binary mixture at supercritical pressure: Influences of cross-diffusion effects

Cross-diffusion effects, including Soret and Dufour effects, are enhanced around the pseudo-critical temperature (Tpc) of a binary mixture. Their influences on heat transfer at supercritical pressure have been scarcely studied. To bridge this gap, large-eddy simulations (LES) are conducted to investigate forced convective heat transfer of a CO2–ethane mixture at supercritical pressures in a circular pipe subject to a uniform heat flux. Both heating and cooling conditions, along with varying initial concentrations and thermodynamic pressures, are included in the simulations. The LES results reveal that the Soret effect causes concentration separation, resulting in a concentration boundary layer. The magnitudes of the thermodiffusion factor (kT) and the radial temperature gradient control the intensity of separation, which is more pronounced at near-critical pressure and high heat flux. Since kT is significant only around Tpc, downstream decay of the concentration separation is observed as the loci of T=Tpc migrate away from the wall so that the local radial temperature gradient diminishes. The primary factors affecting heat transfer are the variations in thermal conductivity and isobaric specific heat resulting from concentration separation. In contrast, the Dufour effect and the accompanying inter-diffusion play negligible roles. In deterioration scenarios, the bulk Nusselt number (Nub) shows a maximum relative drop of 8%, whereas in enhancement scenarios, Nub shows a maximum relative increase in 10%, with both deterioration and enhancement decaying downstream. Cross-diffusion effects have negligible impacts on density and streamwise velocity, but noticeably alter streamwise velocity fluctuation and turbulent kinetic energy.

Investigation on heat transfer of supercritical CO2/Xe mixture crossing pseudo-critical temperature cooled in a horizontal circular tube

Supercritical CO2/Xe mixture has a potential application prospect in the Brayton cycle system from the perspective of thermodynamic. Supercritical cooler is one of the key components there. However, the cooling heat transfer characteristics and mechanism of supercritical CO2/Xe mixture is still unclear, which restricts the development and design of supercritical cooler. The heat transfer of supercritical CO2/Xe mixture crossing Tpc cooled in a horizontal tube with inner diameter 8 mm is numerically explored in this study. The influences of operating parameters on supercritical mixture heat transfer are thoroughly examined. Buoyancy effect is evaluated through the buoyancy criterion Gr/Re2. Further, the mechanism of supercritical CO2/Xe mixture cooling heat transfer is revealed. It is found that heat transfer enhancement may occur during supercritical CO2/Xe cooled process, and heat transfer is weakened when mass fraction of Xe increases. Considering the bulk specific heat and buoyancy dominating jointly the behavior of supercritical cooling heat transfer, a modified Dittus-Boelter correlation is newly developed to predict heat transfer coefficient of supercritical CO2 and its mixture with Xe. The correlation matches well with the experimental and numerical data, and the average relative deviations of the new correlation are 18.27 % and 14.14 %, respectively. The investigation provides insight into the characteristics and mechanism of supercritical CO2/Xe mixture cooling heat transfer. The correlation can provide significant theoretical guidance for accurate design and optimization of supercritical cooler.

Nonequilibrium tricritical behavior in anisotropic XY ferromagnet driven by elliptically polarized propagating magnetic field wave

The three-dimensional anisotropic XY ferromagnet, driven by an elliptically polarized propagating magnetic field wave, has been extensively investigated by Monte Carlo simulation with the Metropolis single spin flip algorithm. Both the effects of the bilinear exchange type and the single-site anisotropies are thoroughly investigated. The time-averaged magnetization (over the complete cycle of the elliptically polarized propagating magnetic field wave) components play the role of the dynamic order parameter. For a fixed set of values of the strength of anisotropy and the field amplitudes, the system has been found to get dynamically ordered at a pseudocritical temperature. The pseudocritical temperature of such a dynamic nonequilibrium phase transition has been found to depend both on the strength of anisotropy and the amplitudes of the elliptically polarized propagating magnetic field wave. A comprehensive phase diagram is represented here in the form of an image plot of the pseudocritical temperature in the plane formed by the strength of anisotropy and field amplitudes. Interestingly, this nonequilibrium phase transition has been found to be discontinuous (first order) for higher values of the field amplitude. On the other hand, the continuous (second order) transition has been noticed for lower values of the field amplitude. Such an interesting nonequilibrium tricritical behavior has been observed in driven XY ferromagnet. The order of such a nonequilibrium phase transition has been confirmed by the thermal variation (near the transition) of the statistical distribution of the order parameter and by the thermal variation of the fourth-order Binder cumulant. In the plane formed by field amplitude and anisotropy, a tricritical line has been shown as the accompanying (and complementary) phase diagram. The dependence of the pseudocritical temperature, on the frequency and wavelength of the elliptically polarized propagating magnetic field wave, has also been reported.

Modal and non-modal stability for Hagen–Poiseuille flow with non-ideal fluid

Modal and non-modal stability analyses are applied to Hagen–Poiseuille flow with a non-ideal fluid. The non-ideal fluid is defined as a fluid close to its vapor–liquid critical point. In this region, properties of the fluid deviate significantly from the assumptions of the ideal gas model. In this paper, the specific example of CO2 near the critical point is taken as a non-ideal fluid. We studied fluids at supercritical pressure and different wall temperatures so that the centerline temperatures can be lower, equal, and higher than the pseudo-critical temperature. Flow instability is characterized by the Reynolds number, and the product of the Prandtl and Eckert numbers. In modal stability analysis, we observe that there is no unstable mode in Hagen–Poiseuille flow with a non-ideal fluid. Regarding the growth rate, as the axial wavenumber increases, another mode becomes the least stable. The non-modal theory is employed to investigate the optimal response to harmonic external force and transient energy growth. The influence of axial and azimuthal wave numbers, Prandtl and Eckert numbers, and thermodynamic states are also taken into account. In this study, we identify an generalized inflection point in the transcritical base profile, causing the transcritical state to be the most unstable. In non-modal instability, we observe that the optimal response mainly occurs at time invariant axisymmetric disturbance. This suggests that the axisymmetric disturbance could potentially initiate the transition to turbulence.

Integrated Optical Diagnostics Of Cyclopentane Sprays To Characterize Transcritical Phase Transitions

This research investigates spray phase transitions under subcritical and transcritical conditions relevant to high-pressure combustion systems. Using advanced optical diagnostic techniques, including shadowgraphy (SH), Mie scattering (MS), and infrared radiation (IR) measurements, the study focuses on cyclopentane sprays in a high-pressure, high-temperature chamber filled with gaseous nitrogen. Three cases are studied to understand spray behavior under varying injection conditions. SH and MS analyses reveal significant differences across the cases. As the chamber temperature increases, the liquid core length shortens, indicating enhanced vaporization. This is particularly evident in the MS images, where step-like transitions in the axial distribution highlight abrupt phase changes from liquid to gas in subcritical conditions. Such transitions are absent under supercritical conditions, suggesting a smoother phase transition process. IR measurements provide additional insights into the spray dynamics, especially under transcritical conditions. The IR images display complex downstream (at x/D > 125) signal patterns with bimodal distributions. The application of inverse Abel deconvolution highlights negative intensities near the spray axis downstream, indicative of regions near the pseudo-critical temperature. This phenomenon, characterized by blocked background radiation due to critical opalescence, offers indirect evidence of the pseudo-critical temperature and the associated phase transition dynamics. Dynamic Mode Decomposition (DMD) analysis identifies dominant frequencies around 4.5 kHz, corresponding to injection pressure fluctuations. This correlation suggests that injection pressure variations significantly influence spray fluctuations. Differences in mode shapes among the cases are also observed; lateral fluctuations near the injector nozzle exit are present in Cases 1 and 2 but not in Case 3. Axial fluctuations beyond a certain length are consistent in all cases. The lateral fluctuations are related to the chamber pressure and the potential large-scale vortex formation or cavitation in the nozzle. The combined use of SH, MS, and IR methodologies provides a comprehensive understanding of transcritical spray dynamics, emphasizing the effectiveness of combining multiple optical diagnostic techniques. These findings will improve numerical simulations and contribute to the development of more efficient high-pressure combustion systems. The research underscores the complexity of phase transitions in sprays and the critical role of precise diagnostics in the advancement of combustion technology.

Assessment of Look-up tables for the prediction of heat transfer coefficient distribution in rod bundles cooled by supercritical water

The evaluation of available Look-Up Tables for prediction of heat transfer coefficient distribution in rod bundles cooled by supercritical water with the aim of their further use in computational analyses of various Fuel Assembles of Supercritical Water-Cooled Reactors is made. The comparison between the calculations based on Look-Up Tables with the values from empirical correlations and experimental data for smooth and wire-wrapped rod bundles was presented. The obtained results showed that Look-Up Table of the University of Ottawa, which was created to describe improved and deteriorated heat transfer regimes in round tubes, allows describing available data points with 30 % of the mean square deviation. It is noted that the presence of wire intensifies heat transfer exchange near pseudocritical temperature region but existing versions of Look-Up Tables cannot take into account this effect. Nevertheless, there is potential for further improvement in predicting the heat transfer coefficient using Look-Up Table by introducing additional correction factors.

Pseudo-scalar meson spectral properties in the chiral crossover region of QCD

Determining the type of excitations that can exist in a thermal medium is key to understanding how hadronic matter behaves at extreme temperatures. In this work we study this question for pseudo-scalar mesons comprised of light-strange and strange-strange quarks, analysing how their low-energy spectral properties are modified as one passes through the high-temperature chiral crossover region between T = 145.6 MeV and 172.3 MeV. We utilise the non-perturbative constraints satisfied by correlation functions at finite temperature in order to extract the low-energy meson spectral function contributions from spatial correlator lattice data in Nf = 2 + 1 flavour QCD. The robustness of these contributions are tested by comparing their predictions with data for the corresponding temporal correlator at different momentum values. We find that around the pseudo-critical temperature Tpc the data in both the light-strange and strange-strange channels is consistent with the presence of a distinct stable particle-like ground state component, a so-called thermoparticle excitation. As the temperature increases this excitation undergoes collisional broadening, and this is qualitatively the same in both channels. These findings suggest that pseudo-scalar mesons in QCD have a bound-state-like structure at low energies within the chiral crossover region which is still strongly influenced by the vacuum states of the theory.

Influence of resonator length and temperature configuration on the performance of a supercritical CO2 thermoacoustic engine

The peculiar properties of CO2 at supercritical pressures and transcritical temperature conditions are favorable for thermoacoustic devices. The printed circuit heat exchanger has been employed to fabricate a standing-wave thermoacoustic engine that works under these conditions. Experiments performed in this paper are devoted to exploring the influences of resonator length and temperature configuration on its performance. Results demonstrate that the oscillation frequency drops when the resonator is elongated, while the pressure amplitude is strengthened. To generalize the experimental data, the power-law relation for pressure amplitude and the bilinear law of frequency are extended to include resonator length as an independent variable, serving as the basis for tuning performance through resonator length. The best temperature configuration is to put the pseudo-critical temperature at the midpoint of heating and cooling temperatures to induce the pressure oscillation at maximum amplitude. Guided by the above results, experiments are performed to explore the extremum of low onset temperature difference. The current record is finally identified as 8.6 °C, close to the literature record of 7.0 °C. This paper elucidates the effects of resonator length and temperature configuration. Conclusions drawn in this paper can guide the design and operation of thermoacoustic devices working with supercritical CO2.

Non-extensive effects on the QCD equation of state and fluctuations of conserved charges within Polyakov quark meson model

The influence of non-extensive Tsallis statistics on the hadron phase structure has been investigated using the Polyakov-quark-meson (PQM) model. The analysis examines the non-extensive effects on the temperature dependence of PQM order parameters, thermodynamic quantities related to the quantum chromodynamics (QCD) equation of state, and fluctuations of conserved charges at varying chemical potentials. The results show that non-extensive effects have the most significant deviations near the crossover region. The pseudo-critical temperature T χ (μ B ) is not a universal constant and decreases with increasing non-extensive q parameter. The chiral phase diagram of the PQM model indicates a decrease in the behavior of the (T χ − μ B ) plane with increasing non-extensive q parameter. The PQM model exhibits good qualitative agreement with lattice QCD calculations. Moreover, these findings suggest the existence of a Tsallis limit, which serves as an alternative to the Stefan–Boltzmann limit for the massless ideal gas. The critical endpoint exhibits lower temperature but higher chemical potential with increasing non-extensive q parameter. Overall, this study highlights the importance of non-extensive Tsallis statistics in characterizing the quark-hadron phase structure of the PQM model and contributes to a deeper understanding of non-extensive effects in the quark-hadron phase transition.

Numerical investigation of jet impingement on flat/concave cooling of CO2 with different phase states under high heat flux

The thermal load and high temperature brought by the increase in power of electronic devices or the increase in speed of supersonic aircraft limit the respective development. In this paper, a numerical model of CO2 jet impingement cooling of a constant heat flux plate/concave surface in different phase states was established. Secondly, the non-equilibrium phase transition and the real-thermophysical properties of CO2 was considered. The effects of different wall heat flux (0.7 MW/m2 ∼ 6.5 MW/m2) and initial phase states on the impact cooling performance of CO2 jet were studied.It is found that for SCO2 jet impingement, when the inlet temperature is lower than the pseudo-critical temperature, the heat transfer coefficient increases with the increase of inlet pressure, and the maximum increase is 24.7 %. For near-critical liquid CO2 (LCO2) jet impingement, low latent heat prevents temperature overshoot in the heat flux range studied. With the increase of the proportion of dry ice in the inlet, the heat transfer coefficient also increases. When q > 3 MW/m2, the heat transfer coefficient of dry ice jet impact is 2.5 ∼ 3 times and 1 ∼ 1.4 times of that of SCO2 and near-critical LCO2 jet impingement for the flat plate model, respectively. For concave surface with high heat flux, near-critical LCO2 jet impingement cooling effect is relatively good. In addition, concave surface will aggravate the uneven cooling surface temperature.The results can provide more references for the CO2 jet impingement technology in the design of stagnation cooling system of supersonic aircraft and thermal management of high-power electronic devices.

Anisotropy and paramagnetism of QCD matter with an anomalous magnetic moment

We employ the Polyakov-loop enhanced Nambu–Jona-Lasinio model incorporating the quark anomalous magnetic moment to investigate the anisotropy structure and the renormalized magnetization of magnetized quark matter at finite temperature. The ultraviolet divergences and nonphysical oscillatory behavior are eliminated by the vacuum magnetic regularization scheme. With a parametrization of the anomalous magnetic moment that is proportional to the square of the chiral condensate, the renormalized magnetization is enlarged by the strong magnetic field so that the anisotropy becomes more apparent. The inflection point of the renormalized magnetization indicates the pseudocritical temperature for the chiral crossover. We find that the results with the anomalous magnetic moment are closer to the lattice quantum chromodynamics data. The connection between the paramagnetism and the chiral transition provides new insight into a magnetohydrodynamics description of hot and dense QCD matter produced in heavy-ion collisions.

الخصائص الفيزيائية والكيميائية الكاذبة والديناميكية الحرارية للغازات الطبيعية

Physiochemical, pseudocritical, pseudoreduced and thermodynamic properties play an important role for determination natural gas quality and specifications. Nowadays natural gas regard as one of the importance natural source of energy supply due to its high heating value, clean source, no emissions and environmental friendly. In addition, it began to replace the oil as a fuel in various purposes and as essential feed for petrochemical industries. Consequently, the different properties of natural gas mixtures must be investigated to determine their specifications. This study was aiming to distinguish these properties using correlations and mathematical models for assessment. These properties include the physical such as molecular weight (M_w), density(ρ), specific gravity(γ), compressibility factor (z), gas viscosity (μ_g), gas formation volume factor (B_g), gas thermal compressibility (C_g) and water content as well as pseudocritical pressure (p_pc), pseudocritical temperature (T_pc), pseudoreduced pressure (p_pr), pseudoreduced temperature (T_pr). Also, the thermodynamic properties e. g. Gross heating value, thermal conductivity, and specific heat of natural gas mixtures were determined. The study has been conducted on the natural gases of Zelten, Al Ragoba, Al Hotaiba gasfields and Al Braiga terminal to predict and estimate the physical, pseudocritical and thermodynamic properties by using correlation and mathematical models methods. The obtained results revealed that there is a variance between these properties of the natural gas mixtures, which may be attributed to the chemical compositions of components and their behaviors. On the other hand, these characterizations can be used as guide to understand the gases behavior during the different operations and natural gases treatment processes. Keywords: Natural gas, physiochemical, pseudocritical, pseudoreduced thermodynamic properties, and correlations

Non-zero temperature study of spin 1/2 charmed baryons using lattice gauge theory

We study the behaviour of spin 1/2 charmed baryons as the temperature increases. We make use of anisotropic lattice QCD simulations with Nf=2+1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$N_f = 2 + 1$$\\end{document} dynamical flavours. After determining the positive and negative parity ground state masses at the lowest temperature, we investigate the effect of rising temperature using ratios of thermal lattice correlators with both so-called reconstructed correlators and with simple model correlators. This avoids difficulties associated with non-zero temperature fitting or spectral reconstruction. We find that temperature effects are prominent throughout the hadronic phase for all negative parity channels considered and for some positive parity channels. Subsequently and where possible, we determine the masses of the ground states as a function of temperature. Finally we consider the effect of chiral symmetry restoration and extract an estimate of the pseudocritical temperature from singly charmed baryonic correlators.

Thermal behavior of effective UA(1) anomaly couplings in reflection of higher topological sectors

Thermal behavior of effective, chiral condensate-dependent UA(1) anomaly couplings is investigated using the functional renormalization group approach in the Nf=3 flavor meson model. We derive flow equations for anomaly couplings that arise from instantons of higher topological charge, dependent also on the chiral condensate. These flow equations are solved numerically for the |Q|=1, 2 topological sectors at finite temperature. Assuming that the anomaly couplings at the ultraviolet scale may also exhibit explicit temperature dependence, we calculate the thermal behavior of the effective potential. In accordance with our earlier study, [G. Fejos and A. Patkos, ], we find that for increasing temperatures, the anomalous breaking of chiral symmetry tends to strengthen toward the pseudocritical temperature (TC) of chiral symmetry breaking. It is revealed that below TC, around ∼10% of the UA(1) breaking arises from the |Q|=2 topological sector. Correspondingly, a detailed analysis on the thermal behavior of the mass spectrum is also presented. Published by the American Physical Society 2024

Thermal evaluation of heat exchanger and a dry-cooled supercritical CO2 mixture Brayton cycle based on three-dimensional and one-dimensional models: Key factors and potential applications

High ambient temperatures in the desert environment and heat capacity mismatch of printed circuit heat exchanger (PCHE) are always main factors that limited cycle efficiency of supercritical CO2 Brayton cycle (SCBC). The SCBC was established to obtain the operating parameters of precooler, low temperature recuperator (LTR) and high temperature recuperator (HTR) in this paper. The performance evaluation factors were developed and applied. The findings demonstrated that the precooler total heat transfer coefficient (HTC) peaked near the pseudo-critical temperature. Smaller hot-side pressure, larger hot-side and cold-side mass flux could improve heat transfer performance (HTP) of the precooler. The CO2-H2S in the precooler had larger HTC and pressure drop (ΔP), the CO2-Propane in the LTR and HTR had larger total HTCs and ΔP for the same critical temperature. Heat transfer correlations about the precooler of pure CO2 and CO2 mixtures were proposed. A conclusion was drawn by analyzing the performance evaluation factors that the PCHE using CO2-H2S for the precooler and CO2-Propane for the LTR and HTR could achieve better HTP under the same ΔP, but had the smaller effectiveness under the same ΔP. The CO2-H2S had the potential for practical application because of the larger cycle thermal efficiency and relatively good tolerance to the change of critical temperature.

Toward Predicting Interfacial Tension of Impure and Pure CO2-Brine Systems Using Robust Correlative Approaches.

In the context of global climate change, significant attention is being directed toward renewable energy and the pivotal role of carbon capture and storage (CCS) technologies. These innovations involve secure CO2 storage in deep saline aquifers through structural and capillary processes, with the interfacial tension (IFT) of the CO2-brine system influencing the storage capacity of formations. In this study, an extensive data set of 2811 experimental data points was compiled to model the IFT of impure and pure CO2-brine systems. Three white-box machine learning (ML) methods, namely, genetic programming (GP), gene expression programming (GEP), and group method of data handling (GMDH) were employed to establish accurate mathematical correlations. Notably, the study utilized two distinct modeling approaches: one focused on impurity compositions and the other incorporating a pseudocritical temperature variable (Tcm) offering a versatile predictive tool suitable for various gas mixtures. Among the correlation methods explored, GMDH, employing five inputs, exhibited exceptional accuracy and reliability across all metrics. Its mean absolute percentage error (MAPE) values for testing, training, and complete data sets stood at 7.63, 7.31, and 7.38%, respectively. In the case of six-input models, the GEP correlation displayed the highest precision, with MAPE values of 9.30, 8.06, and 8.31% for the testing, training, and total data sets, respectively. The sensitivity and trend analyses revealed that pressure exerted the most significant impact on the IFT of CO2-brine, showcasing an adverse effect. Moreover, an impurity possessing a critical temperature below that of CO2 resulted in an elevated IFT. Consequently, this relationship leads to higher impurity concentrations aligning with lower Tcm values and subsequently elevated IFT. Also, monovalent and divalent cation molalities exhibited a growing influence on the IFT, with divalent cations exerting approximately double the influence of monovalent cations. Finally, the Leverage approach confirmed both the reliability of the experimental data and the robust statistical validity of the best correlations established in this study.