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Achieving room-temperature superconductivity under ambient conditions is one of the most important goals in solid-state physics and material science. Recent discoveries of high-Tc superconductivity in binary hydrides H3S and LaH10 at high pressures have focused the search for room-temperature superconductors on dense hydrides with conventional phonon-mediated pairing mechanisms. In this study, we predict a novel family of superconducting ternary hydrides under moderate compression, XC2H8 (X = Ga, In, Tl, Sn, Pb, Sb, Bi, Te, Po). Unlike H3S and LaH10, these new materials are stable at just around 20 GPa. Among the analyzed compounds, SbC2H8 exhibits the highest critical temperature of 73 K at a pressure of 100 GPa, which is attributed to its energetically favorable high-symmetry crystal structure ( F m 3 ¯ m ), high density of states at the Fermi level (1.27 states/eV) and strong electron–phonon coupling constant (1.02). We expect that our findings provide crucial insights into achieving high-temperature superconductivity at moderate pressures and accelerate the progress of experimental research. [ABSTRACT FROM AUTHOR]

The paper investigates the flow around two non-identical height buildings, each with the same square cross-section, arranged in tandem using a particle image velocimetry technique. Fixed gap spacing between objects G = 1. 5 D (where D is the side building's length) and fixed Reynolds number R e = 17000 were considered in the study. The key goal of the research was examining the effect of the angle of attack α in the range from 0 ° to 30 ° on the flow structure. Considerable attention was paid to assessing the ventilation performance for the investigated flow configurations. Also, the pedestrian-level wind conditions were evaluated for all the considered values of the angle α. When α grows up, the flow is more prone to enter the gap space and elevates locally the velocity in that region. When the flow leaves the gap on the other side, it mixes with the side shear layer and both generate the recirculation area next to the downstream buildings. As α increases, the highest values of the turbulence kinetic energy are seen outside the gap space. The strength of the downwash and upwash effects on the symmetry plane becomes reduced with growing α. No clear dependency between the Strouhal number and the angle α was observed. The contribution of α to the ventilation process in the gap is different at different heights. A conversion from the weak to tolerable wind condition takes place in the gap when α increases. • Effect of angle of the attack α is studied using PIV approach. • Just a small change in α breaks the flow pattern symmetry. • As α increases, most of TKE production takes place outside the gap. • Contribution of α on the ventilation process in the gap vary with height. • Share of tolerable wind condition is insensitive to the wind direction. [ABSTRACT FROM AUTHOR]

The paper is devoted to the amine-based post-combustion carbon dioxide capture technology. The aim of the paper was to analyze the effect of varying flow conditions on the CO2capture efficiency of the absorber column. As a research tool, a numerical model of the chemical absorption with aqueous monoethanolamine solution in a packed bed was employed. A complex physio-chemical process including two-phase flow hydrodynamics, heat transfer, and absorption chemistry was simulated by Ansys Fluent commercial software. The parametric study was focused on CO2capture efficiency in terms of varying loads of amine solvent (liquid) and flue gas. The corresponding changes of liquid holdup, species concentration, temperature and reaction rate distributions are discussed in detail allowing to better understand the absorption column operation. The simulation results have shown clearly the mutual interactions of partial processes and the sensitivity of the system to varying column loads. They have been found to be useful in defining the optimal ranges of operational parameters. [ABSTRACT FROM AUTHOR]

Concerns over greenhouse gas emissions are driving a requirement for newly built coal power units to satisfy the so-called “capture ready” conditions. This paper presents the a thermo-economic analysis supplemented by a cost evaluation of a power unit for ultra-supercritical parameters expanded by an amine-based CO2 capture plant. The analysis was performed with the use of an integrated package containing the IPSEpro, MATLAB and Revenue Requirement Method implemented in MOExcel. The 0D model of a post combustion capture installation was developed based on complex CFD calculations of the absorber and stripper. A number of CFD simulations were conducted to create a large database, which was then utilized to develop suitable correlations describing the process Thermodynamic and economic calculations were performed in respect of a power plant coupled with a CO2 separation unit for a varying ratio of amine solvent to the exhaust gas stream (L/G). A local minimum for reboiler heat duty was found for L/G≈3.5 revealing the optimal post combustion capture configuration. It was observed that complementing the power unit with a post-combustion capture (PCC) installation causes a slight increase in the investment costs due to the drop in efficiency, but more important is the rise in total cost due to the investment associated with the CO2 capture plant. It was found that about 14 years is required to compensate the investment cost of the PCC installation. [ABSTRACT FROM AUTHOR]

The paper deals with the computational fluid dynamics modelling of carbon dioxide capture from flue gases in the post combustioncapture method, one of the available carbon capture and storage technologies. 30% aqueous monoethanolamine solution was used as a solvent in absorption process. The complex flow system including multiphase countercurrent streams with chemical reaction and heat transfer was considered to resolve the CO2 absorption. The simulation results have shown the realistic behaviour and good consistency with experimental data. The model was employed to analyse the influence of liquid to gas ratio on CO2 capture efficiency. [ABSTRACT FROM AUTHOR]

The paper concerns research aimed at developing a computational fluid dynamics (CFD) model of an amine-based carbon dioxide capture process in post-combustion capture (PCC) technology. A numerical model of the absorber column (the first stage of PCC cycle) including complex hydrodynamics, heat transfer and absorption reaction involving monoethanolamine (MEA) was developed and described in detail in [1, 2]. This paper focuses on the second stage of the PCC cycle: the desorber (stripper) column. An Eulerian multiphase model was adopted to resolve two-phase counter-current gas-liquid flow in a porous region with desorption reaction, multiphase heat transfer and evaporation/condensation phenomena. The preliminary calculations were performed on simplified geometry of the stripper column in order to reduce the computational time required. The results showed physically correct behavior, proving its relevance and utility for practical applications. [ABSTRACT FROM AUTHOR]