Cellulose stabilized multiphase systems (CSMS) have garnered significant attention due to their ultra-stabilization mechanism and vast potential across different fields. CSMS have found valuable ...applications in scientific disciplines, including Food Science, Pharmaceutical Science, Material Science, and related fields, owing to their beneficial attributes such as sustainability, safety, renewability, and non-toxicity. Furthermore, MPS exhibit novel characteristics that enable multiple mechanisms to produce HIPEs, aerogels, and oleogels revealing undiscovered information. Therefore, to explore the undiscovered phenomena of MPS, molecular level insights using advanced simulation/computational approaches are essential. The molecular dynamics simulation (MDS), play a valuable role in analyzing the interactions of ternary interphase. The MDS have successfully quantified the interactions of MPS by generating, visualizing, and analyzing trajectories. Through MDS, researchers have explored CSMS at the molecular level and advanced their applications in 3D printing, packaging, preparation, drug delivery, encapsulation, biosensors, electronic devices, biomaterials, and energy conservation. This review highlights the remarkable advancements in CSMS over the past five years, along with contributions of MDS in evaluating the relationships that dictate the functionality and properties of CSMS. By integrating experimental and computational methods, we underscore the potential to innovate and optimize these multiphase systems for groundbreaking applications.
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•A review of cellulose stabilized multiphase systems with multiple scientific applications.•Summarize the role of CSMS in allied Sciences.•Analyzed the theoretical, analytical, and computational studies of cellulose MPS.•Molecular dynamic simulation shed light on the oil/air/water phase interactions.•The role of MDS in multiphase systems is still limited.
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•Three node CHyQMOM is successfully implemented in OpenFOAM-7.•The algorithm can capture particle trajectory crossing without delta shocks.•For wall bounded problems results are not ...accurate.•Attention should be paid to prevent over-accumulation.
The modeling of dilute gas-particle flows is challenging due to particle-trajectory crossing (PTC). Lagrangian particle tracking can be used, but requires a large number of parcels resulting in high computational costs. A less costly method is the Eulerian number density function (NDF) approach, based on the Boltzmann equation, often solved in terms of lower-order moments of the NDF. In this context the conditional hyperbolic quadrature method of moments (CHyQMOM) was developed and is here implemented for the first time in the OpenFOAM-7, together with high-order advection schemes and a new operator splitting procedure. The resulting solver is used to simulate different test cases: phase segregation problems, collision-less and weakly-collisional PTC flows, asymmetric and symmetric Taylor-Green vortex flow and a dilute gas-particle riser. Results, validated against analytical solutions and predictions obtained with Lagrangian particle tracking, show that the implemented CHyQMOM can be used to handle highly non-equilibrium flows.
The Cover Feature shows the potential of multiphase liquid systems for the oxidation of 5‐hydroxymethylfurfural (HMF) with tunable selectivity. By modifying the constituents of the multiphase system ...and the reaction parameters, the protocol allows complete control of the reaction selectivity that goes from partial to deep oxidation of both the hydroxy and carbonyl functions of HMF, allowing also for the in‐situ recycling of the catalyst in a semicontinuous mode. More information can be found in the Research Article by D. Polidoro et al.
Chemistry in water enabled by surfactants offers remarkable benefits from compliance and sustainability standpoints. It has consequently significantly grown and gained the major interest of synthetic ...organic chemists in the last decade. Rapid growth and adoption have mostly occurred through an increasing number of examples of successful, selective syntheses of desired products, although numerous and significant gaps remain in understanding the physico-chemical and mechanistic aspects of the applied surfactant-based aqueous reaction media. Further developments on these fronts should allow for a much larger impact in the future.
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•Growing interest within industry, on aqueous micelles and multiphase systems as reaction media with the opportunity to move away from fossil feedstock.•Still limited understanding of the physico-chemical and mechanistic phenomena that govern synthesis in aqueous surfactant-based systems.•Requirement of strong collaborative efforts towards a better understanding of “micellar catalysis” and to unleash its full potential.
The growing interest in electrical machines equipped with multiphase configurations has directed the research to the conception of new design methods and optimization strategies to maximize the ...performance and the efficiency of the machine for its specific application. In this context, a noticeable gap persists in the comprehensive generalized theory of multiphase systems applied to electrical machines. Therefore, this article aims to propose a new possible classification of multiphase systems based on the electrical symmetries between the corresponding star of slots phasors, starting from the general law related to the spatial distribution of the air-gap magnetic flux density field. This theory extends beyond symmetrical configurations, encompassing both reduced and normal systems, which can be derived from redundant multiphase configurations. Furthermore, the proposed generalization applies to all possible <inline-formula><tex-math notation="LaTeX">m</tex-math></inline-formula>-phase configurations, including the structures with slight asymmetries or unbalances. The article provides illustrative examples to reinforce these theoretical concepts to establish a systematic and unified theory and classification that can be adopted for any possible topology of a multiphase system.
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•First principle simulations of droplet breakup in turbulent flow.•Analysis of stochastic breakup and validation with experimental data.•Qualitative and quantitative agreements ...between simulations and experiments.•Higher order fragmentation linked to intensity of vortex interaction.
This study investigates single droplet breakup from a theoretical perspective and addresses whether breakup in turbulent flows can be studied using highly-resolved simulations. Transient and three-dimensional turbulent flow simulations are performed to investigate if the apparent stochastic outcome from the droplet breakup can be predicted. For a given turbulent dissipation rate the breakup events were simulated for various detailed turbulence realizations. For this purpose, a well-characterized system widely used for kernel development is utilized to validate the simulations with respect to the key characteristics of stochastic breakup, including droplet deformation time, the number of fragments, and the specific breakup rate. The statistical validations show very good agreement with all the quantitative properties relevant to the breakup dynamics. Necklace breakup is also observed in line with patterns found in experiments. Evidence is found that the rate of energy transfer is positively correlated with higher order fragmentation. This can allow development of more accurate breakup kernels compared to the ones that only relies on the maximum amount of energy transfer. It is concluded that the simulation method provides new data on the stochastic characteristics of breakup. The method also provides a means to extract more details than experimentally possible since the analysis allows better spatial and temporal resolutions, and 3D analysis of energy transfer which provides better accuracy compared to experimental 2D data.
•Current knowledge on process design and enhancement with OBRs is reviewed.•Depending on the baffle geometries, additional design parameters may be needed.•Micromixing performance in OBRs still needs ...to be explored.•Parameters other than plug flow may be a priority depending on the process goal.•The implementation of OBRs is still challenging for some applications.
The continuous oscillatory baffled reactor (OBR) is a particular type of tubular reactor, which has drawn increasing attention over the past few decades due to the benefits it provides in terms of intensification of heat and mass transfer, as well as equipment compactness compared with stirred tank reactors. This process enhancement is principally due to the interaction of the oscillatory flow with internal baffles and the consequent generation of transverse flows and eddies. Continuous OBRs are already applied in several industrial sectors, however these reactors present certain limitations in terms of operating conditions and the range of possible applications. This review presents and discusses the current knowledge on continuous OBR design guidelines, performance characterization and applications. It aims to guide the selection of the most appropriate continuous OBR design, as well as the characterization criteria, according to the type of application and final process objective.
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Using the vector space decomposition approach, the currents in a multiphase machine with distributed winding can be decoupled into the flux and torque producing α-β components, and the loss-producing ...x-y and zero-sequence components. While the control of α-β currents is crucial for flux and torque regulation, control of x-y currents is important for machine/converter asymmetry and dead-time effect compensation. In this paper, an attempt is made to provide a physically meaningful insight into current control of a six-phase machine, by showing that the fictitious x-y currents can be physically interpreted as the circulating currents between the two three-phase windings. Using this interpretation, the characteristics of x-y currents due to the machine/converter asymmetry can be analyzed. The use of different types of x-y current controllers for asymmetry compensation and suppression of dead-time-induced harmonics is then discussed. Experimental results are provided throughout the paper, to underpin the theoretical considerations, using tests on a prototype asymmetrical six-phase induction machine.
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•A new method for bubble size and velocity detection in fluidized beds was developed.•Method uses 3D capability of electrical capacitance volume tomography sensor.•Lateral and radial ...bubble movement, coalescence and splitting were detected and described.•Measurement method was validated and agrees with published data.
This work sets forth the development of a novel, dynamic bubble detection algorithm for use with electrical capacitance volume tomography (ECVT) sensors for bubbling fluidized beds. Starting with an in-depth review of existing bubble detection methods, the novel phase detection method was developed to address the shortcomings of the other published methods by more fully utilizing the three-dimensional capability of the sensors. After the sensor parameters were optimized to verify capability of bubble detection, measurements were made with glass beads and quartz sand. A range of air velocities in a 10 cm diameter bubbling fluidized bed were used. The results largely agree with the fundamentals of bubbling fluidization and results from publications with similar experimental setups. Within each measurement the bubble dimensions, velocities and frequencies over the axial and radial position could be evaluated. Due to the three-dimensional nature of the novel bubble detection technique, insight into the directional tendencies of detected bubbles was gained. For example, bubble migration toward the radial center of the bed, radial and axial bubble coalescence, and splitting are more evident from the trends that are producible with this method.
The imaging of particulate media – encompassing both the imaging of the particles themselves, as well as the study of their dynamics and bulk properties and behaviours – is crucial to improving our ...understanding of a diverse range of phenomena and processes spanning numerous scientific disciplines and industrial sectors. Despite interdisciplinary interest in the field and the availability, and continuous development, of a wide range of different imaging techniques, there exist nonetheless a number of limitations of these techniques, and open challenges – both technical and non-technical – facing the field as a whole. In this perspective, we discuss in detail five such challenges, identified by a team of interdisciplinary experts spanning both academia and industry: how can we work toward the imaging of systems which are more ‘real-world-relevant’, both in terms of composition and scale? How can we extract detailed, quantitative information regarding stresses from such systems? How can we image processes which are both rapid and transient, when most current technologies can manage (at best) only one of these states? How can we ensure closer and more fruitful collaboration between the academics developing particle imaging technologies and the potential industrial end-users who stand to benefit from them? How can we improve the visibility of the field and the educational opportunities available to the potential next generation of particle technologists? As one may expect for such a broad range of questions, the answers to the above are diverse and numerous. However, there are certain key themes running through them. Above all, our work highlights a need for improved collaboration, be that in terms of experts in multiple different imaging technologies working together to perform multi-modal studies so as to address the technical limitations highlighted above, researchers and industry professionals finding new ways to engage, or academics co-creating open-source educational tools to support the next generation of particle imaging experts.
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•A perspective on the key challenges facing the particle imaging field•Summarises 3 major technical challenges and 2 non-technical challenges•Offers an outlook on how these may be addressed•Improved collaboration between academic fields and industrial sectors is a priority
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