This paper introduces a quantum lattice Boltzmann method for simulating complex flows. The proposed quantum scheme effectively overcomes the mismatch between the nonlinear collision in the standard lattice Boltzmann method (LBM) and the linear quantum computing (QC) through a linearized non-equilibrium collision operator, and is successfully extended to the Navier-Stokes systems by designing a modular circuit for density and velocity calculations. Most importantly, the present approach ensures the unitary of quantum algorithms while keeping the collision relaxation parameter adjustable for simulating flows with different Reynolds numbers. The accuracy and practicality of the proposed method are demonstrated by simulating two typical flows, including lid-driven and natural convection flows in a square cavity at different Reynolds and Rayleigh numbers, respectively. This work offers a practical application of QC-based LBM for complex fluid dynamics problems.

This work conducts a systematic and comprehensive theoretical analysis of numerical instability and numerical accuracy verification for the recently proposed lattice Boltzmann method (LBM) with non-equilibrium linearized collision (NLC-LBM). Through the rigorous Chapman–Enskog kinetic expansion method, the NLC-LBM accurately decomposes the nonlinear terms in the collision operator into equilibrium and non-equilibrium components, and then performs consistent linearization on the non-equilibrium components. This treatment not only completely retains the physical essence of fluid flow and ensures the physical accuracy of the simulation, but also effectively suppresses the divergence of high-wave-number modes in numerical calculations, fundamentally improving the numerical instability of traditional methods. This improvement not only significantly enhances the numerical stability under coarse mesh conditions in classical computing scenarios, solving the bottleneck of easy instability in coarse mesh simulation, but also provides a solid theoretical foundation and adaptation support for the currently rapidly developing quantum-classical hybrid linear computing architecture, laying the foundation for the integrated application of LBM and quantum computing. Based on the Von Neumann linearized instability theory, this paper deeply analyzes the local instability characteristics and hydrodynamic dissipation behavior of the NLC-LBM. Through comparative analysis with the standard LBM, it is clearly demonstrated that the stability of the NLC-LBM under coarse mesh conditions is significantly superior to that of the standard LBM, thereby providing a highly stable and reliable collision model for the efficient and stable simulation of complex flows under coarse mesh conditions. To further verify the physical effectiveness and numerical accuracy of the NLC-LBM, this paper conducts systematic numerical simulation research on three classic benchmark cases, including lid-driven cavity flow, natural convection, and vortex pair merging. The results show that under the same coarse mesh conditions, the standard LBM exhibits obvious non-convergence, characterized by non-physical features such as streamline distortion and velocity profile oscillation; while the NLC-LBM can maintain stable convergence of the flow field and accurately capture the flow characteristics. Under fine mesh conditions, both the computational results and numerical accuracy of the NLC-LBM are basically consistent with those of the standard LBM, fully verifying the physical rationality and numerical reliability of the method.

This study proposes an enhanced immersed boundary-lattice Boltzmann method (IB-LBM) incorporating distribution function correction for gas-liquid-solid multiphase flow simulations. The methodology characterizes the fluid-solid interactions disturbing the surrounding fluid through non-equilibrium distribution function analysis within the IB-LBM framework. A phase-field approach coupled with the conservative Allen-Cahn equation governs gas-liquid interface evolution, while an integrated scheme combining weighted capillary force calculation and diffused interface immersion boundary treatment addresses dynamic wetting phenomena at moving contact lines. Validation through four typical benchmark simulations, i.e., (1) a droplet spreading on a cylinder, (2) particle wetting behavior at a gas-liquid interface, (3) a circular cylinder submersion through an air-water interface, and (4) interfacial self-assembly of a triple-particle system, demonstrates the method’s reliability. Then, a systematic study of a particle that falls and collides with another particle at the air-water interface is conducted to investigate further the phase-significant deformation phenomenon accompanied by complex particle interaction in multiphase flow. Numerical simulations confirm the method’s capability to accurately model multiphase systems with multiple particles while maintaining mass conservation principles.

The lattice Boltzmann method (LBM) has evolved over the past three decades into a powerful and widely used computational framework for simulating multiphase and multicomponent flows. This unique hybrid review combines a large-scale bibliometric analysis with an in-depth thematic review, providing a comprehensive perspective on current developments and future trends in multiphase LBM. Bibliometric results of 5657 publications (1991–2025) reveal exponential growth in publications, strong international collaboration networks, and a clear shift from early interface-capturing schemes toward more stable, physically consistent, and high-performance formulations. The thematic review highlights core families of multiphase LBM models, including color-gradient, pseudopotential, free-energy, and phase-field approaches, emphasizing their theoretical foundations, strengths, limitations, and representative applications. Emerging trends such as high-density-ratio stabilization, wetting and contact-line modeling, hybrid LBM-continuum solvers, machine-learning-accelerated LBM, and GPU-optimized implementations are also discussed. The review further provides a comparative discussion of leading multiphase models alongside the core challenges in the field and the strategies proposed to address them. Finally, the key future directions are outlined, including exascale-ready algorithms, data-driven closure models, quantum-inspired LBM formulations, and thermodynamic consistency for extreme regimes. Together, this work provides a concise and integrated overview of the intellectual and technical advances in multiphase LBM, serving as an essential reference for researchers seeking to understand its evolution, current status, and future directions.

Solar-driven interfacial evaporation presents a promising solution to the global freshwater crisis. However, achieving an optimal balance between evaporation rate, efficiency, mechanical properties, stability, and durability remains a significant challenge. In this study, we present a novel PVA/PPy-enhanced loofah-based evaporator that integrates biomass materials with dual-network hydrogel. Unlike previous approaches focused on improving single parameters (e.g., evaporation rate or efficiency), our design synergistically enhances multiple critical properties, including light absorption, superhydrophilicity, and mechanical strength. A quantitative model was developed to optimize design parameters, linking the deformation capacity of CL-PVA/PPy to the evaporator's aspect ratio. This model enabled a high evaporation rate of 1.821 kg m- 2 h- 1 and a conversion efficiency of 94.81 % under 1 Sun illumination. Long-term stability tests confirm the evaporator's durability, making it a promising solution for sustainable freshwater generation. Additionally, integrating multifunctional modules, including a condenser, enables a cumulative evaporation of 15.551 kg m- 2 over 8 h, supporting the daily drinking water needs of over four people. This work provides a scalable and efficient design, combining material sustainability with high performance, and paves the way for large-scale applications in water harvesting and agriculture.

As a mesoscopic method in computational fluid dynamics, the lattice Boltzmann method (LBM) exhibits a strong alignment with quantum computing paradigms through its discrete velocity space and local evolution rules. Existing quantum lattice Boltzmann method (QLBM) has largely been confined to linearized equilibrium distribution functions, which require computation of macroscopic quantities at each time step. This limitation restricts its capability to handle nonlinear flow problems and leads to an increased computational overhead. This paper presents a (QLBM) for solving the vorticity-stream function equations for practical nonlinear flows. The core work is constructing a linearized non-equilibrium collision matrix with naturally coupling the treatments of periodic boundary condition and source term under the standard LBM frame, and the elements in the matrix are updated solely by particle distribution functions. Two classic vortex dynamics cases are selected for validation: (1) the Taylor-Green vortex, examining vortex decay due to viscous dissipation, where normalized enstrophy and maximum vorticity evolution curves closely match analytical solutions; and (2) the vortex pair merging problem, verifying the rotation, convergence, and merger of two co-rotating vortices under mutual induction, successfully reproducing typical vortex interaction dynamics. The results demonstrate that the present QLBM exhibits good temporal evolution accuracy and spatial discretization precision, providing an effective pathway for applying quantum computing to vortex dynamics simulations.

Low fabrication rate and high material costs hindered the wide applications of laser powder bed fusion (LPBF) in tooling industries. To address these issues, this study investigated the feasibility of manufacturing stainless steel CX (SS-CX) at large by using coarse powder particle via large LPBF layer thicknesses at 80 & micro;m and 100 & micro;m, and the influences of layer thickness on microstructure and mechanical properties were explored. Through the process parameter optimizations, LPBF fabricated SS-CX specimens achieved high relative densities of 99.99 % for both 80 and 100 & micro;m layer thickness. Microstructural analyses revealed that horizontal specimens exhibited finer grains and higher austenite fractions than those in vertical counterparts, which resulted in superior yield strength and ductility in horizontal specimens. An increased layer thickness to 100 & micro;m slightly reduced impact toughness, which was attributed to the increased porosity levels.

This paper presents an enthalpy-based lattice Boltzmann flux solver for simulating droplet freezing in a uniform electric field. The solver is validated against the three-phase Stefan problem, droplet freezing on a cold surface, and droplet deformation in a uniform electric field, demonstrating its accuracy and robustness for electrofreezing applications. It is then employed to investigate the effects of the conductivity and permittivity ratios (Cr and Pr) on droplet freezing dynamics. The results show that Cr and Pr markedly modify the distribution interfacial free charges, thereby reshaping the droplet, altering the contact-line length, and regulating heat transfer. Although Cr and Pr are varied independently, their influence fundamentally arises from their combined effect on the charge relaxation time ratio tau(rel)= Pr/Cr. A transition in freezing behavior occurs when the charge relaxation times of the droplet and the surrounding medium become comparable (tau(rel) =1), which corresponds Cr = Pr = 2 for the material parameters used in this study. For tau(rel)< 1, positive-charge accumulation compresses the droplet, enlarges the contact line, enhances heat flux into the cold substrate, and shortens the freezing time. In contrast, for tau(rel) > 1, negative charges dominate, stretching the droplet, reducing the contact line, weakening heat transfer, and prolonging the freezing process. These findings indicate that the electrical properties regulate freezing primarily through charge-relaxation-controlled interfacial electrohydrodynamics, with the freezing time governed by the resulting changes in droplet morphology rather than by modifications to the underlying freezing mechanism.

An enthalpy-based unified lattice Boltzmann flux solver (EULBFS) is proposed in this paper for simulating liquid solidification, incorporating the effects of volume expansion and shrinkage caused by density differences between liquid and solid phases. The proposed solver first establishes the relationships between the macroscopic governing equations and mesoscopic formal equations that describe the temperature, flow, and phase fields. The macroscopic governing equations are then discretized by the finite volume method (FVM), with the corresponding fluxes calculated based on the established relationships. In this way, it enables a unified and coherent solution framework for all fields. In contrast to the conventional lattice Boltzmann methods, the present approach handles additional terms directly via finite volume discretization, offering a more straightforward and flexible formulation. Furthermore, the use of the total enthalpy equation to couple the temperature field with the phase fraction allows for efficient modeling of phase change processes, significantly reducing the computational complexity associated with interface tracking. The accuracy and robustness of the proposed solver are demonstrated by a series of benchmark tests, including the conductive freezing problem, the three-phase Stefan problem, the freezing of a liquid film in a two-dimensional container, the solidification of a static droplet on a cold surface, and the freezing of a droplet upon impact with a cold surface.

The impact of ferrofluid droplets on hydrophobic cylindrical surfaces under magnetic fields has attracted increasing attention due to its potential applications in water repellence, anti-icing, and drag reduction. In this work, the anisotropic spreading dynamics of a ferrofluid droplet impacting an asymmetric geometric structure are systematically investigated through combined experimental, numerical, and theoretical analyses. The results show that the spreading behaviour of the ferrofluid droplet is primarily governed by the magnetic field strength, impact Weber number, and surface curvature ratio. As magnetic flux density increases, the axial spreading diameter decreases, while the time required to reach the maximum spreading grows correspondingly. A theoretical model is further developed to predict the maximum spreading diameter of ferrofluid droplets under the influence of magnetic fields, showing good agreement with experimental results.

A lattice Boltzmann flux solver based on an enthalpy formulation is developed to simulate the freezing dynamics of the immiscible compound droplet. The solver is validated against several benchmark problems, involving the spreading of a compound droplet, conduction-dominated freezing in a semi-infinite space, and a static droplet freezing on a flat substrate. Using the validated solver, the freezing behavior of an immiscible compound droplet on a supercooled flat substrate is systematically investigated. The Stefan number is found to primarily rescale the overall freezing time, while the normalized evolution of the freezing fronts remains largely unaffected. Within this regime, the distinct roles of key governing parameters are identified. The solid–liquid density ratio ρsl mainly affects volumetric deformation and the final frozen morphology, while the inner-to-outer radius ratio Rio governs geometric partitioning and the associated thermal resistance. In contrast, the solid–liquid specific heat ratio Cpsl and λsl thermal conductivity ratio regulate transient energy transport during solidification. Overall, the results provide a clear qualitative understanding of the respective roles of geometry, thermophysical properties, and volumetric deformation in the freezing process of the compound droplet under conduction-dominated conditions.

Halide perovskite quantum dots (HPQDs) are transformative candidates for next-generation optoelectronic devices, owing to their exceptional optoelectronic properties including widely tunable bandgaps, ultrahigh color purity, and solution processability. However, scalable, deterministic synthesis of high-quality HPQDs with simultaneous ultra-narrow emission linewidth and high photoluminescence quantum yield (PLQY) remains a longstanding challenge, fundamentally limited by the mass transfer bottleneck and poor mixing efficiency of conventional laminar microreactors. Here, we report a biomimetic vein-inspired ultrasonic microreactor integrated with sharp-edged microstructure arrays to address this core challenge. Through systematic multiphysics simulations, we quantitatively decode the acoustic-hydrodynamic coupling mechanism in the microreactor, and establish a quantitative structure-performance relationship between microstructure geometry and sonochemical reaction performance. We identify an optimized cylindrical microstructure configuration that synergistically amplifies acoustic streaming and cavitation yield to break laminar boundary layer confinement. Experimental validation confirms the optimized microreactor enables continuous synthesis of high-quality HPQDs with an ultra-narrow full width at half maximum of 23.28 nm and PLQY up to 78.6%, markedly outperforming conventional microfluidic methods. We further elucidate that cavitation-enhanced micromixing enables dynamic supersaturation tuning, driving LaMer-type size-focusing and homogeneous nucleation for exceptional HPQDs monodispersity. This work provides a generalizable, scalable microfluidic strategy for precision synthesis of high-performance optoelectronic nanomaterials, bridging the critical gap between lab-scale research and industrial translation.

In this study, an enthalpy-based lattice Boltzmann flux solver is developed to simulate the freezing dynamics of a ferrofluid droplet under a uniform magnetic field. The accuracy and robustness of the solver are first validated through three benchmark tests: conductive freezing, static droplet freezing, and ferrofluid droplet deformation. The solver is then employed to investigate the influence of a uniform magnetic field on the freezing behavior of ferrofluid droplets, focusing on the overall freezing process, heat transfer characteristics, and freezing duration. The results reveal that the uniform magnetic field affects the freezing dynamics primarily by altering the droplet morphology. Under a vertically oriented magnetic field, the droplet elongates along the field direction, which increases the thermal resistance and consequently prolongs the freezing time. Conversely, a horizontally uniform magnetic field flattens the droplet, reducing the thermal resistance and thus shortening the freezing time. These findings provide new physical insight into magnetic-field-induced modulation of the freezing process in ferrofluid systems.

Carbon dots (CDs) are promising fluorescent nanomaterials with broad applications in optoelectronics, healthcare, and artificial photosynthesis. However, synthesizing indigo-emitting CDs with optimal properties remains challenging due to the inefficiencies and complexity of conventional methods. This study introduces a high-performance ultrasonic microreactor inspired by biomimetic leaf vein structures to enhance CD synthesis efficiency. We developed a COMSOL Multiphysics-based optimization framework to improve flow field uniformity and examine transport dynamics within the microchannel. This framework identified key parameters, including leaf vein contours, fractal angles, depth-to-width ratios, and inlet configurations, that govern flow characteristics. Additionally, we optimized ultrasonic energy transfer by directly coupling the transducer with the microreactor, determining the optimal frequency (21 kHz) and power (100 W) for maximum reactor performance. Visualization experiments revealed how ultrasound regulates bubble dynamics, enhancing interfacial area and stabilizing suspension behavior. Using this optimized system, we synthesized indigo-emitting CDs with a maximum PLQY of 27.5 % and a narrow FWHM of ∼78 nm under 365 nm excitation. Multivariate experiments revealed how flow velocity, reaction temperature, and ultrasonic modulation influence the optical properties of the CDs. This work underscores the synergistic combination of ultrasonic energy, biomimetic design, and simulation-guided optimization, providing a solid foundation for scalable synthesis of carbon-based nanomaterials with applications in optoelectronics, healthcare, and beyond.

Halide perovskite solar cells (HPSCs) are a promising technology for solar energy conversion, owing to their low cost and high efficiency. However, their practical deployment is limited by instability and degradation under prolonged sunlight exposure. This study addresses these challenges by integrating fluorescent solar concentrators (FSCs) with HPSCs. FSCs, which combine fluorescent materials with an optical waveguide medium, offer a promising solution by enhancing light harvesting while reducing the direct exposure of solar cells. We present a multi-colored carbon dots (CDs)-based FSC designed to tackle key issues related to light efficiency, reabsorption, and stability. The CDs are synthesized to exhibit high photoluminescence quantum yield, substantial Stokes shifts, and excellent photothermal stability. Additionally, the optical waveguide structure is optimized through simulation tools to maximize light gathering efficiency. Simulation results demonstrate that a five-layered equilateral triangular waveguide structure can achieve up to 100% light gathering efficiency, effectively overcoming the limitations of traditional materials' refractive indices. The integration of optimized FSCs with HPSCs reduces temperature stress, mitigates UV degradation, and minimizes spatial footprint. The combination of the multi-colored CDs and optimized waveguide structure leads to a significant performance boost, achieving an optical efficiency of up to 16.95%. This work offers a cost-effective and scalable approach for improving the optical efficiency and stability of HPSCs, with promising applications in building-integrated photovoltaics, smart windows, and rooftop solar systems.

Surface rupture in ferrofluid layers is a special case of the well-known Rosensweig instability, which can be triggered by applying a strong magnetic field. This study investigates the rupture dynamics in a ferrofluid interlayer sandwiched between two non-magnetic fluids, influenced by a non-homogenous vertical magnetic field. Simulations are performed using a generalized conservative phase-field lattice Boltzmann method for the flow field and interface with a coupled solution of Maxwell's equations for the evolution of magnetic field. The numerical results demonstrate the complete rupture process of ferrofluid layers. In most cases, the ferrofluid layer ruptures into two parts, while under certain conditions, such as a thinner interlayer or high magnetic field intensity, daughter droplets appear at the meniscus. A parametric analysis involving Weber number (We) and dimensionless magnetic parameter (Nm) elucidates the connection between different rupture conditions, such as a deformed interlayer without rupture, rupture with two semi-spindle shaped domains, and rupture with droplets. Additionally, a phase diagram illustrating the various rupture regions is also provided.

Droplet impact on curved surfaces is a common phenomenon in both industrial processes and the natural world. Prediction and design of advanced technologies, such as cell processing and biotechnology printing, require an in-depth understanding of the dynamics of compound droplet impacts. However, there is a significant scarcity of research concerning the dynamics of compound droplets impacting on curved surfaces. This study employs numerical simulations to investigate the impact dynamics of a compound droplet on a curved surface over a range of Weber number (We) and Reynolds number (Re). The numerical approach employed here is an immersed boundary lattice Boltzmann method. The numerical simulation results reveal that both the We and Re have a pronounced effect on the spreading, contraction, and rupturing, of compound droplets on a curved surface. An analysis, with We and Re as key factors, elucidates their influences on the impact behavior of compound droplets. Furthermore, based on the phase diagram of impact results on the We and Re coordinate axes, two split lines are introduced for the first time, delineated by inertia, viscosity, and surface tension forces. These split lines provide clear guidance on controlling the droplet impact pattern by changing either We or Re, thereby facilitating accurate predictions of compound droplet impact results.

Noise pollution is an urgent environmental issue that leads to a series of adverse effects on human physical and mental health. Porous materials with rationally designed micropores or channels can effectively absorb noise across wide frequency ranges, making them a well-established candidate for mitigating acoustic propagation. However, common porous materials with a singular pore structure face a trade-off between acoustic absorption efficiency and thickness. Herein, this challenge is significantly mitigated by reconstructing the pore structure of commercial melamine foam using multiwall carbon nanotubes (MWCNTs). The melamine/MWCNTs foam exhibits multiscale composite pores, high porosity, and increased specific surface area while preserving the shape and thickness of the initial melamine foam. Due to increased energy dissipation from the porous structure and the resonance effect of MWCNTs, the 10 mm thick composite porous absorber exhibits an average absorption coefficient of ≈70% from 1300 to 6000 Hz, representing a 196.5% increase compared with that of initial melamine foam. The reconstructing pore structure by loading MWCNTs is a simple and general method for improving the acoustic absorption coefficient. It can be extended to other complex morphologies or material systems, offering significant application potential in noise control, acoustic instruments, and architectural design.

The development of flexure-based XYZ micro-positioning stages incorporating a novel type of flexure hinges with elliptical transverse cross-sections (ETC) is presented. In comparison to classical two-axis flexure hinges featuring rectangular transverse cross-sections (RTC), parametric studies of both the flexure hinges and the flexure stage were conducted, focusing on stress concentration, motion range, and output decoupling. The results demonstrate that the ETC-based XYZ flexure stage outperforms the RTC-based design in all three aspects. A prototype of the XYZ flexure stage utilizing ETC-type two-axis flexure hinges was developed and experimentally tested, achieving motion errors and parasitic motions of less than 5%. The ETC-type two-axis flexure hinges offer a novel approach for advancing spatial flexure stage design.

In this paper, we develop a lattice Boltzmann-based diffuse interface immersed-boundary scheme for gas-liquid-solid multiphase flows. Based on the conservative phase-field lattice Boltzmann method and the immersed boundary method (IBM), the fluid-particle interaction is modeled by a momentum exchange-based IBM for the flow field and a diffuse interface-based IBM with two layers of fictitious body-fitted Lagrangian grids for the phase field. We applied the method to simulate a series of cases of gas-liquid-solid multiphase flows including a squared cylinder standing still at gas-liquid interface, a circular cylinder standing still at gas-liquid interface, a light circular cylinder freely suspending at gas-liquid interface, two/three circular particle assembling at gas-liquid interface, and a number of circular particles randomly floating from liquid part to assembling at the gas-liquid interface. The proposed scheme can accurately characterize the mechanisms of dynamic wetting and interfacial interactions at the mesoscopic scale and has shown advantages in simulating complex gas-liquid-solid coupling problems.