In the microfluidic systems, the structure of micromixer is one of the important influence factors for the mixing performance. The traditional trial-and-error method for the optimization design of micromixer structure is difficult to consider both the mixing performance and power dissipation. Here we show the topology optimization method of designing the passive micromixer with the minimum power dissipation

A separator coupling cyclone with a built-in granular bed filter is proposed for gas purification. Due to the complicated mutual influences between the outer cyclone shell and the inner granular bed, the dust deposition is different from that in the traditional granular bed filter. By using the intrusive sampling method, the dusts deposited in the bed are sampled under varying inlet dust concentrations

The study presents a novel ANN-CFD model for simulating flow in a vortex mixer (an unbaffled vessel stirred by a magnetic stirrer). Large eddy simulations (LES) are performed to simulate flow and turbulence considering presence of both air and liquid phases. The flow fields in air and liquid phases are coupled by applying suitable boundary conditions at the gas-liquid interface represented by the vortex

A systematic method is proposed for targeting the optimal catalyst service life, considering the catalyst deactivation and coupling integration of HEN and reactor. Relations among the reactor’s conversion, inlet/outlet temperature, energy consumption, average product cost, and catalyst activity are determined based on the catalyst deactivation kinetics, energy balance, and the migration of the composite

Piperacillin, an important penicillin, is generally synthesized by N-acylation of ampicillin and 4-ethyl-2,3-dioxo-1-piperazinecarbonyl chloride (EDPC) at the oil-water interface. A membrane dispersion microreactor can be used to synthesize high-quality piperacillin. However, research on the kinetics model of this process is limited. In this study, a high-speed microscope camera system was used to

Metal-organic frameworks (MOFs) have been considered as promising physical adsorbents for hydrogen storage due to their high porosity and structural tunability. We selected 7643 real MOFs from the computation-ready MOF 2019 database to screen high-performance materials for hydrogen storage based on the grand canonical Monte Carlo (GCMC) simulations. Based on the obtained data set, we proposed a deep

We present a VOF-based numerical method for incompressible Direct Navier–Stokes (DNS) equations for diffusion-driven phase-change flows. A special emphasis is placed on the treatment of velocity discontinuities across the interface. A novel algorithm is presented to smoothly extend the liquid velocity field across the interface in a way that the interface can be transported by a divergence-free velocity

Adsorption is widely used for gas separation and storage. Its performance relies heavily on the selection of suitable adsorbents. In this work, a data-driven neural recommender system is developed for a preliminary adsorbent screening. Over 32,000 single-component isotherms are retrieved from the NIST isotherm database. After a series of filtering steps, 16,470 isotherms related to gaseous adsorbates

We investigate bubble dynamics in a submerged double-jet as an example of weakly coupled, Lagrangian transport. The setup resembles continuous casting of steel at Reynolds numbers Re=136000 to Re=272000. Using short time series of flow fields obtained from large-eddy simulations (LES) with a discrete bubble model, we calculate a database of transport patterns and time-extrapolate them to long durations

Despite the large quantity of works dedicated to the analysis and modelling of deposition in single-phase flows, very few models have been proposed for deposition of solids in two-phase pipe flows of gas and liquid. A comprehensive mechanistic model for transient, multiphase pipe flow with phase change is proposed, which takes into account effects of deposition by mass diffusion, ageing, and shearing

Simultaneous optimization of EDC and ethane concentrations to maximize ethylene oxide production rate (rEO) over a commercial catalyst at 17.4 bar, 213–240 °C and in the GHSV range of 3000–5000 h−1 was done in this study. The feed composition and operating conditions were chosen similar to those in the industry, so that the findings are practical. EDC and ethane concentrations in the feed are merged

An industrial-scale Fischer–Tropsch (FT) slurry bubble column reactor (SBCR) was theoretically investigated, emphasizing the mass transfer between the gas and slurry phases. In this endeavor, three different driving forces for mass transfer (the impetus behind the motion of species mass) were proposed: one based on Henry’s law and two based on rigorous phase equilibrium. The mass transfer model based

We study the effect of intra-tumor heterogeneity on the dynamics of a growing tumor, utilizing a two-dimensional continuum model. The cancerous phase is divided into two sub-phases, with the second characterized by a mutation. In addition, the vascular phase is categorized into two sub-populations based on their maturity. Nutrient chemical species are supplied by the vasculature and transferred throughout

The corona discharge is widely used to charge fog droplets. However, there is a lack of an accurate description of the interaction between fog droplets and the corona discharge process. Discharge currents of the two wire-plate devices in two foggy environments were measured experimentally. It was found that fog droplets floating in the air restrained the corona discharge process, and the effect of

The effect of surface heterogeneity of solid substrate on the wetting behavior of sessile droplets is systematically investigated. A theory is proposed to predict the contact angle by considering the droplet to be a spherical cap and the contact line to have a width. Comprehensive molecular dynamics (MD) simulations are implemented to validate this theory, which shows good agreement. Based on this

The most sophisticated descriptions of particle-particle cohesion rely on extremely sensitive and resource-intensive measurements, often making them impractical for industrial application. The focus here is to experimentally assess the “square-force” cohesion model (Liu et al., 2018), which (i) incorporates the two quantities that dictate interactions, namely cohesive force and energy, and (ii) involves

Distillation and absorption processes are characterized by a large number of state variables. In order to reconstruct and predict these state variables under off-design and limited measurement conditions, this paper combines the proper orthogonal decomposition (POD) method with the nonlinear autoregressive with exogenous input (NARX) data-driven model. The POD method can reduce the full-order variables

In this work, Ag nanoparticles as surface plasmon catalysts were prepared on polydopamine microspheres via in-situ reduction for catalytic 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride. The kinetics of catalytic reaction under light and dark conditions was compared. It was found that the reaction rate constant under light condition was increased by 53.6% due to the surface plasmon

In this work, a modular millireactor (MMR) is designed and modeled using the computational fluid dynamics (CFD) tool OpenFOAM. First, the method is validated against a conventional packed bed reactor (PBR) model (1D) with Aspen Plus. Next, the method is applied to study the effects of pressure (2–6 MPa) and temperature (483–533 K) on the performance of the MMR. Conjugate heat transfer (CHT) CFD results

The facile and rapid fabrication of super-hydrophobic microfluidic channels has numerous bio- and physico-chemical applications. In this study, we present a simple, fast, and inexpensive method to fabricate a super-hydrophobic polydimethylsiloxane (PDMS) microchannel. The method involves using xurography-based PDMS micromolding with a silicon carbide paper. The microchannel exhibited a micro-textured

The magnesium manganese oxide redox system shows great promise for use in grid-scale, long duration thermochemical storage. We measured the equilibrium extent of oxidation, y=yeq, of the MgMnO2+y system, in a series of thermogravimetric relaxation experiments. Temperatures and oxygen partial pressure ranges are 1000–1500 °C and 0.01–0.9 atm respectively. The equilibrium oxygen stoichiometry ranges

Colliding micro-dispersion has been extensively used to generate uniform droplets in liquid-liquid heterogeneous reactions. However, there are few reports on the colliding micro-dispersion. More importantly, only squeezing flow and big size droplets can be generated in the normal colliding micro-dispersion process, and even there exists no general scaling laws for droplet size. We have developed novel

Bubble formation routes are vital to the application of microreactors, but a systematic understanding of the vertical squeezing remains lacking. Accordingly, this study focuses on the vertical squeezing bubble generation mechanism in viscous liquids in a T-junction microchannel. The results show there are the retraction, expansion, shrinking, and necking formation stages in the vertical squeezing route

In traditional just-in-time learning (JITL)-based adaptive soft sensors for complex chemical process, relevant sample selection and local model construction are carried out separately, resulting in that the developed predictive models are usually lack of optimality and validity. This has long been a tough issue for the JITL-based soft sensors. Therefore, this paper proposes a novel unified JITL paradigm

This paper proposed a nonintrusive, in-situ experimental method for visualizing and measuring the mean residence time (MRT) of supercritical-pressure pipe flow with/without chemical reactions based on the high-frequency sampling of laser-induced particle images. Normal and oblique optical arrangements (NOA & OOA) for the incident laser were applied to induce particle scattering in the JP-10 pipe flow

In order to gain a more fundamental understanding of binary particle systems, a two-dimensional (2D) fluidized bed was used to study the bubble dynamics and dense phase composition. Digital image analysis (DIA) was employed to measure bubble diameter, bubble rise velocity, bed expansion, and the distribution of the two types of particles in the bed. Magnetite and sand particles as the single components

The aim of this paper was to develop a deeper understanding of the mixing processes in biogas plants and to explore potentials for optimization with respect to efficient mixing. Since slow-running agitators have a higher energy efficiency than high-speed submersible mixers, the focus was placed on paddle agitators. In order to achieve more effective mixing, different agitator positions were compared

Helically coiled tubes (HCTs) are widely used in industries owing to their compact structure and excellent heat and mass transfer efficiency. Due to the complexity of three-dimensional flow in HCTs, profound knowledge on the flow pattern characteristics is not well documented in existing literature. In this paper, we employ the wire-mesh sensor (WMS) and image tomography technique to measure a series

Defect-free slot coating is important in the design and manufacturing of lithium-ion-battery electrodes. However, the defect formation in electrode-slot coating is not clearly understood because of the involvement and coupling of many parameters. Here, we investigate the defect formation mechanisms in electrode-slot coating by using numerical and experimental methodologies. Three defects, namely, striped