Purpose This paper aims to explore dual solutions for the flow of a hybrid nanofluid over a permeable melting stretching/shrinking sheet with nanoparticle shape factor, second-order velocity slip conditions and viscous dissipation. The hybrid nanofluid is formulated by dispersing alumina (Al2O3) and copper (Cu) nanoparticles into water (H2O). Design/methodology/approach The governing partial differential

Purpose This study aims to investigate the heat and mass transfer characteristics of a temperature-sensitive ternary nanofluid in a porous medium with magnetic field and the Soret–Dufour effect through a tapered asymmetric channel. The ternary nanofluid consists of Boron Nitride Nanotubes (BNNT), silver (Ag) and copper (Cu) nanoparticles, with a focus on understanding the thermal behaviour and performance

Purpose This paper aims to study numerically the non-Newtonian solution of carboxymethyl cellulose in water along with copper oxide nanoparticles, which flow turbulently through twisted smooth and finned tubes. Design/methodology/approach The twisted-tape inserts of rectangular and triangular sections are investigated under constant wall heat flux and the nanoparticle concentration varies between 0%

The Internal flow mechanisms and windage loss in impeller back gap of a supercritical carbon dioxide (sCO2) radial inflow turbine with scallops are comprehensively investigated in this paper. The study emphasizes the effects of scallop depth and leakage outlet pressure. The results indicate that scallop structures lead to a degradation in overall turbine performance. Under design conditions, a turbine

Purpose This research focuses on the controlling irreversibilities in a radiative, chemically reactive electromagnetohydrodynamics (EMHD) flow of a nanofluid toward a stagnation point. Key considerations include the presence of Ohmic dissipation, linear thermal radiation, second-order chemical reaction with the multiple slips. With these factors, this study aims to provide insights for practical applications

Despite the impressive characteristics of biological metal organic frameworks (bioMOFs) for their use as drug delivery systems (DDs), there are still some parameters related to their structural stability and processing routes that have decelerated their realistic application in this field. Both drawbacks are unraveled in this work for the microporous bioMOF CaSyr-1 by using supercritical CO2 (scCO2)

This research investigates the extraction of compounds from Nepeta crispa (N. crispa), utilizing supercritical carbon dioxide green solvent, for the first time. Using RSM, the study examines the impact of pressure (15–25 MPa), temperature (313–333 K), and co-solvent (0.5–3.5%) on the extraction yield. The antioxidant activity of the essential oil is assessed through Ferric Reducing Antioxidant Power

Sediment flushing through bottom tunnels has been widely applied in engineering practice to alleviate reservoir sedimentation. However, there is limited understanding of whether flushing can be acc...

In the cockpit, minimising the pilots' thermal discomfort due to solar exposure while ensuring clear visibility is essential. This study numerically examined the solar radiation effect on thermal f...

High-pressure gas might affect the molecular chain movement, chain interaction, and crosslinking behavior of MVQ during the saturation process. In this paper, by comparing crosslinking exothermic behaviors of MVQ in air, CO2, and N2, it is found that the supercritical CO2 (scCO2) can promote crosslinking reaction of MVQ through enhancing the swelling and molecular chain's mobility. The result of rheological

Purpose This paper aims to present a numerical investigation for two-dimensional fractional Helmholtz equation using the Aboodh integral homotopy perturbation transform scheme (AIHPTS). Design/methodology/approach The proposed scheme combines the Aboodh integral transform and the homotopy perturbation scheme (HPS). This strategy is based on an updated form of Taylor’s series that yields a convergent

Steam explosion (SE) pretreatment and sequentially subcritical water hydrolysis (SWH) was studied. Industrially, there is an advantage in using this process strategy, since it uses the same equipment and instrumentation, without the need to transport the raw material in separate stages. The influence of severity factors (SF) (2.75, 3.05, and 3.35) and solvent used (distilled water and 0.5 % w/w of

This pioneering study is the first to explore the extraction of Calycolpus goetheanus using supercritical carbon dioxide (scCO2), novel approach to harnessing the bioactive potential of this Amazonian species. By examining extractions under varying temperatures (35 and 45 °C) and pressures (150, 250, and 350 bar), the research not only evaluates the yields but also uncovers significant differences

Dyes abundance in wastewaters poses environmental threats, and a cost-effective strategy to remediate dyed water is adsorption: this process could be enhanced using nanostructured sorbents, that expose high surface areas.

The impregnation of piperine and black pepper extract into poly (L-lactic acid) (PLLA) films using supercritical CO2 was investigated. Piperine was a model to determine the influence of operating conditions of pressure (10 and 12 MPa) and temperature (40 and 50 °C) on the impregnation yield. The most favorable conditions were obtained at 10 MPa and 50 °C and were used in the incorporation of piperine

We developed a methodology to study the extraction of high-value solutes directly from suspensions of finely disrupted substrates. For that, we modelled the high-pressure phase equilibrium for the ternary (CO2 + ethanol + water) system using experimental literature data. Different compositions of hydroethanolic mixture and CO2 were loaded into an extraction vessel set at 30–35 MPa and 40–50 °C during

Supercritical carbon dioxide (SC-CO2) was used as an alternative method of dyeing alpaca fiber. This study analyzes the colorfastness to laundering as a function of operating parameters. The fiber was subjected to a pretreatment (Impregnation), where it was soaked in an acidulated solution of Nylosan Yellow N-3RL dye, squeezed through a padder roller and then dyed in the SC-CO2 system. Dye concentrations

The computation of Global Phase Equilibrium Diagrams (GPED) for binary systems, including critical and three-phase equilibrium curves, is crucial for analyzing process conditions and assessing thermodynamic models. In the past two decades, algorithmic strategies and GPEC software have become essential tools. However, numerical problems can arise with the original algorithm for highly asymmetric systems

Purpose Double flow-focusing nozzles (DFFNs) form a coaxial flow of primary liquid with micro-crystalline samples, surrounded by secondary liquid and focusing gas. This paper aims to develop an experimentally validated numerical model and assess the performance of micro-jets from a DFFN as a function of various operating parameters for the water–ethanol–helium system, revealing the jet's stability

Purpose Using passive techniques like twisted tapes and corrugated surface is an efficient method of heat transfer improvement, since the referred manners break the boundary layer and improve the heat exchange. This paper aims to present an improved dual-flow parabolic trough collector (PTC). For this purpose, the effect of an absorber roof, a type of turbulator and a grooved absorber tube in the presence

Purpose This study aims to investigate entropy generation through natural convection and examine heat transfer properties within a partially heated and cooled enclosure influenced by an angled magnetic field. The enclosure, subjected to consistent heat production or absorption, contains a porous medium saturated with a hybrid nanofluid blend of Cu-Fe3O4 and MoS2-Fe3O4. Design/methodology/approach The

Purpose Carotid artery is often associated with plaque deposition because of its shape and associated flow features. The shape of stenosed bifurcation is characterised by bifurcation angle (ß), planarity angle (α) and severity of stenosis (b). In the present work, three-dimensional numerical computations have been performed to analyse the effect of these geometrical parameters of carotid bifurcation

Renowned for its medicinal properties, barbatimão bark extract contains bioactive compounds susceptible to degradation, necessitating their safeguarding within a stable matrix for diverse biomedical applications. This study investigates using high-pressure liquid impregnation (HPLI) to load barbatimão extract into biopolymeric membranes at 30, 45, and 60 °C, and 11 MPa. HPLI combines the simplicity

Purpose Two-phase R-744 ejectors are critical components enabling energy recovery in R-744 heat pump and refrigeration systems, but despite their simple geometry, the flow physics involve complex multiphase mixing phenomena that need to be well-quantified for component and overall system improvement. This study aims to report on multiphase mixture simulations for a specific two-phase R-744 ejector

Purpose This study aims to investigate the formation and characteristics of Taylor bubbles resulting from short-time gas injection in liquid-conveying pipelines. Understanding these characteristics is crucial for optimizing pipeline efficiency and enhancing production safety. Design/methodology/approach The authors conducted short-time gas injection experiments in a vertical rectangular pipe, focusing

The experimental conditions of supercritical carbon dioxide (scCO2) extraction of virgin palm oil (VPO) from oil palm mesocarp fiber (OPMF) were optimized using the Response Surface Methodology (RSM). Results showed that a maximum of 28.68 % of VPO extraction was obtained at the optimal experimental conditions of scCO2 extraction: pressure of 31 MPa, temperature of 340 K, and extraction time of 80 min

C-phycocyanin (CPC) is a phycobiliprotein present in spirulina, which, due to its blue color, non-toxic nature, fluorescent and antioxidant properties, is of interest in the food and pharmaceutical industries. Different methods of extraction and stabilization are being investigated, including supercritical CO2 extraction, a method applied to obtain bioactive compounds from plant matrices. In this work

In this study, the use of supercritical CO2 (scCO2), and compressed propane (CP) were applied to obtain a crude extract rich in d-limonene (DL) from Ponkan waste from the juice industry. The moisture content of the dried waste was 8.53 % and a particle size of 28 mesh was determined for the extractions. Soxhlet extraction was performed with 5 g of waste and 150 mL of n-hexane and showed an extraction

Purpose This paper aims to reduce the cost of experiments required to test the efficiency of materials suitable for artificial tissue ablation by increasing efficiency and accurately forecasting heating properties. Design/methodology/approach A two-step numerical analysis is used to develop and simulate a bioheat model using improved finite element method and deep learning algorithms, systematically

Purpose This study aims to present the consequences of activation energy and the chemical reactions on the unsteady MHD squeezing flow of an incompressible ternary hybrid nanofluid (THN) comprising magnetite (FE3O4), multiwalled carbon nano-tubes (MWCNT) and copper (Cu) along with water (H2O) as the base fluid. This investigation is performed within the framework of two moving parallel plates under

Purpose This paper aims to focuses on by investigate the heat transmission and free convective flow of a suspension of nano encapsulated phase change materials (NEPCMs) within an enclosure. Particles of NEPCM have a core-shell structure, with phase change material (PCM) serving as the core. Design/methodology/approach The enclosure consists of a square chamber with an insulated wall on top and bottom

This study investigates the effectiveness of macaúba oil extraction using supercritical carbon dioxide, focusing on determining operational parameters such as temperature and pressure that maximize the quality and yield of the extract obtained. The extraction was carried out using freeze-dried macaúba pulp, under varying conditions of pressure and temperature. The overall yield isotherms of macaúba

This study investigates the mixing behavior in a Y-junction mixer for supercritical water hydrolysis using large eddy simulation with a discrete phase model. Yield changes were simulated using a two-step reaction model with first-order kinetics, based on particles’ temporal temperature data. Effective mixing produced closely matched mass and particle flow temperature distributions, both exhibiting

Researchers are mainly interested in using soft computing artificial intelligence (AI) methods due to their broad applications in analysis, modelling and simulations. Backpropagation neural network...

Purpose This study aims to investigate time-harmonic wave propagation in a chiral porous thermoelastic solid under strain gradient theory (SGT), focusing on identifying and characterizing distinct wave modes within the medium. Design/methodology/approach Using Iesan's gradient theory, which incorporates chiral effects and accommodates second sound phenomena, the authors derive mathematical formulations

Purpose This study aims to analyze the thermo-hydrodynamic characteristics for the mixed convection boundary layer flow of three-particle aqueous nanofluid on a shrinking porous plate with the influences of thermal radiation and magnetic field. Design/methodology/approach The basic equations have been normalized with the help of similarity transformations. The obtained equations have been solved numerically

In this study, the erosion characteristics of eutectic high entropy alloy under the liquid–solid two-phase flow is investigated by a coupled numerical-experimental method, in order to reveal the in...

The catalytic hydrogenation of fumaric acid, a prominent bioplatform molecule, was evaluated over PdRe/SiO2 within a variety of reaction media compositions comprising methanol, water, supercritical CO2, and their assorted combinations with H2, across a range of temperature and pressure regimes. Meticulous manipulation of the reaction media composition facilitated the precise modulation of catalytic

This study investigates the influence of vibration on droplet dynamics when a droplet impacts a three-dimensional (3D) structured porous medium, focusing on intrinsic properties such as porosity an...

Understanding the settling behaviour of particles and the interactions between fluid and particles in channelled fluids is crucial for various natural and industrial processes. The research present...

Hesperidin is a rutinoside of flavanone type with relevant therapeutic properties but poor water solubility which limits its therapeutic applicability. However, cyclodextrins (CDs) have been successfully used as drug carriers to enhance the solubility of several drugs, to improve their bioavailability, and therapeutic efficacy. We report herein the formation of inclusion complexes of β-cyclodextrin

this study considers the high-pressure behavior of thymol + carvone Natural Deep Eutectic Solvent using a combined experimental and computational approach. Experimentally, PVT (pressure – volume/density - temperature) measurements were conducted to characterize the fluid volumetric behavior as well as compressibility and internal pressure, which are directly related with hydrogen bonding and nanoscopic

The problem of the geodynamo is simple to formulate (Why does the Earth possess a magnetic field?), yet it proves surprisingly hard to address. As with most geophysical flows, the fluid flow of molten iron in the Earth's core is strongly influenced by the Coriolis effect. Because the liquid is electrically conducting, it is also strongly influenced by the Lorentz force. The balance is unusual in that

This review provides a comprehensive analysis of the literature on vortex-induced vibration (VIV) of flexible circular cylinders in cross-flow. It delves into the details of the underlying physics governing the VIV dynamics of cylinders characterized by low mass damping and high aspect ratio, subject to both uniform and shear flows. It compiles decades of experimental investigations, modeling efforts

Turbulence is often studied by tracking its spatiotemporal evolution and analyzing the dynamics of its different scales. The dual to this perspective is that of an observer who starts from measurements, or observations, of turbulence and attempts to identify their back-in-time origin, which is the foundation of data assimilation. This back-in-time search must contend with the action of chaos, which

Sesame cake was submitted to pressurized liquid extraction (PLE) for process optimization. Then, supercritical fluid extraction (SFE), followed by optimized PLE were applied to recover the oily fraction and the polar extract, respectively. PLE samples, at optimized condition and from SFE deffated cake, showed high levels of TPC (33.15 and 31.86 mg GAE/g), DPPH (97.64 and 94.38 µmol TE/g), FRAP (46

A fundamental understanding of the interfacial properties at elevated pressure is essential for processes in the context of the energy transition, such as the storage of CO2, H2 or CH4. Systems in such processes have traces of impurities. This work aims to systematically investigate these multi-component systems through simplified vapor-liquid-liquid systems comprising H2O, (n-butanol or n-dodecane)

The supercritical CO2 impregnation of pink pepper essential oil (EO) can bring its bioactive properties to a biomaterial in a green approach, making it multifunctional. Aiming to obtain a gelatin-siloxane cryogel loaded with pink pepper EO for biomedical applications and to understand the impact of the impregnation conditions, gelatin was crosslinked with (3-glycidoxypropyl)trimethoxysilane and lyophilized

As there is a risk of CO contamination by vehicles running inside the car park. This research was initiated with the objective of assessing jet fans' impulsive ventilation “IV” performance and stud...

Two different kinetic models were developed for the kinetic study of Domanic oil shale conversion in the supercritical water. The oil shale reaction order was evaluated with a three-lump reaction scheme taking into account oil shale, gases, and synthetic oil. Contrary to the commonly reported first-order, it was found that a higher order (2.5) is more suitable for the conversion of oil shale at supercritical

Praziquantel (PZQ) is an anthelmintic drug with low solubility, therefore cocrystallization and particle size reduction is desirable to improve bioavailability. In this study, a PZQ-malonic acid cocrystal was micronized by rapid expansion of supercritical solution (RESS). Due to low solubility in scCO2, four cosolvents were screened as RESS modifiers. While addition of acetone or THF yielded mixtures

Among the various natural disasters, the death caused by flash flood is the highest. Recently, the combination of deep learning methods and hydrodynamic models has shown superior performance in the...

Purpose In recent times, ternary hybrid nanofluid has garnered attention from scientist and researchers due to its improved thermal efficiency. This study aims to delve into the examination of ternary hybrid nanofluid (Al2O3–Cu–TiO2/water), particularly concerning axisymmetric flow over a nonlinearly permeable stretching/shrinking disk. In addition, the investigation of convective boundary conditions

Purpose This study focuses on investigating the numerical solution of second-kind nonlinear Volterra–Fredholm–Hammerstein integral equations (NVFHIEs) by discretization technique. The purpose of this paper is to develop an efficient and accurate method for solving NVFHIEs, which are crucial for modeling systems with memory and cumulative effects, integrating past and present influences with nonlinear

The climatic wind tunnel (CWT) is widely recognised as the optimal experimental environment for studying vehicle rainwater management, while the rainfall field generated by the CWT for vehicles may...

The weld crack leakage due to stress concentration and external load is a significant safety risk in pressure pipelines. Microstructural variations and dynamic propagation lead to unpredictable cha...

Computational Fluid Dynamics (CFD) plays a crucial role in investigating new physical phenomena and exploring the principles of fluid mechanics. However, CFD numerical methods often face the challe...

Chemical gradients, the spatial variations in chemical concentrations and components, are omnipresent in environments ranging from biological and environmental systems to industrial processes. These thermodynamic forces often play a central role in driving transport processes taking place in such systems. This review focuses on diffusiophoresis, a phoretic transport phenomenon driven by chemical gradients

Ice structures such as accretion on airplanes, wires, or roadways; ice falls; ice stalactites; frozen rivers; and aufeis are formed by the freezing of capillary flows (drops, rivulets, and films). To understand these phenomena, a detailed exploration of the complex coupling between capillary flow and solidification is necessary. Among the many scientific questions that remain open in order to understand

This study aimed to develop an efficient method for converting residual biomass into biofuel through a process that combines supercritical fluid extraction and hydrothermal liquefaction. The study analyzed the compositional changes in the biomass residues using various co-solvents and assessed their potential for biofuel production. After hydrothermal liquefaction, the liquid biofuel produced showed