Publication library

Publication results

1. Published October 11, 2026

   Industrial applications

   Design and Operating Principles of Rotor-Stator Mixers

   Rotor-stator mixers concentrate mechanical energy within narrow clearances, moving passages, stator openings, and discharge jets. Process performance depends not only on deformation intensity within the mixing head but also on the transport of material through that region. Accordingly, batch immersion, single-pass inline processing, and tank recirculation require different approaches to evaluating capacity, residence time, and cumulative exposure. This article presents an integrated engineering description of mixer construction, rotor and stator geometries, single-stage and multistage arrangements, and the mechanisms of dispersion, emulsification, and agglomerate breakup.

2. Published October 1, 2026

   Industrial applications

   Sonochemical Effect Induced by Hydrodynamic Cavitation

   Hydrodynamic cavitation can generate chemical effects analogous to those associated with acoustic sonochemistry while operating through spatial pressure reduction and recovery in a flowing liquid rather than through an imposed acoustic field. This article examines the physical and chemical basis of these effects, including bubble growth and inertial collapse, adiabatic compression, gas and vapor composition, radical generation, interfacial chemistry, and transport into the bulk liquid. The analysis distinguishes thermal, interfacial, bulk, and mechanically assisted reaction pathways and evaluates the influence of device geometry, pressure recovery, temperature, dissolved gas, bubble cloud structure, and repeated exposure. Chemical dosimetry, energy normalization, high speed imaging, luminescence, and thermal diagnostics are considered as complementary methods for establishing a defensible evidence chain from hydraulic forcing to chemical output. Representative applications include advanced oxidation, disinfection, inorganic synthesis, crystallization, organic and multiphase processing, biomass treatment, and food and beverage processing. Experimental evidence demonstrates that maximum visible vapor volume does not necessarily correspond to maximum chemical yield because bubble interaction, shielding, recombination, and collapse location affect productive energy focusing. The principal scale up objective is therefore to preserve the pressure history, active bubble population, chemically productive collapse exposure, gas condition, residence time distribution, and energy boundary required for the target reaction while controlling erosion, contamination, and safety.

3. Published October 1, 2026

   Reactors & equipment

   Hydrodynamic Cavitation in Emulsification and Homogenization

   Hydrodynamic cavitation is increasingly applied to emulsification and homogenization because cavity growth and collapse generate intense, localized pressure gradients, microjets, and turbulent dissipation within continuous flow equipment. This article examines the coupled hydraulic, interfacial, and kinetic mechanisms governing droplet breakup and stabilization and reviews the principal models used to describe cavitation assisted emulsification. Static constrictions, Venturi devices, vortex reactors, and dynamic rotor stator systems are evaluated with respect to cavitation regime, pressure recovery, residence time, energy input, and product response. Emulsion quality is treated as a distributional problem rather than a single mean diameter, with emphasis on Sauter mean diameter, coarse droplet tails, interfacial area, recoalescence, and storage stability. The analysis covers Kolmogorov and Hinze scaling, Rayleigh collapse relations, the Kozyuk and Fedotkin bubble field model, population balance methods, and reduced order descriptions, together with their assumptions and validation requirements. Published results are considered for vegetable oils, proteins, dairy systems, cosmetics, pharmaceuticals, fuels, and specialty chemical applications. Particular attention is given to backpressure, pass number, viscosity, phase fraction, emulsifier concentration, temperature, dissolved gas, erosion, sanitation, scale up, and process control. The evidence indicates that maximum visible cavitation does not necessarily correspond to optimum homogenization. Industrial performance is better defined by a validated operating window that couples droplet size distribution and stability with throughput, energy, thermal history, chemical quality, cleanability, and equipment durability.

4. Published October 1, 2026

   Industrial applications

   Hydrodynamic Cavitation for Wastewater Processing

   Hydrodynamic cavitation (HC) is evaluated as a process intensification method for wastewater treatment, sludge pretreatment, ballast water treatment, disinfection, and oxidation of refractory organic contaminants. The article examines aqueous reaction zones, reactor configurations, hydraulic operating windows, hybrid oxidation, sludge disintegration, biological inactivation, scale up, energy accounting, materials, and control requirements. The reviewed evidence indicates that treatment performance is governed by the controlled sequence of cavity inception, growth, transport, and collapse and by interaction with the water matrix rather than by cavitation number or pressure alone. Static and rotational reactors can intensify oxidation, mass transfer, particle disintegration, microbial inactivation, precipitation, and anaerobic digestion, but response depends strongly on contaminant properties, dissolved gas, solids, radical scavenging, backpressure, temperature, residence time, and auxiliary chemistry. Case studies demonstrate nonmonotonic pressure response, limited standalone mineralization in strongly scavenging matrices, improved methane yield after optimized sludge disintegration, and enhanced micropollutant removal when HC is coupled with hydrogen peroxide, ozone, Fenton chemistry, plasma, or other advanced oxidation processes. Scale up should preserve process function and be verified through continuous pilot testing, energy normalization, byproduct and toxicity assessment, and asset condition monitoring. HC is therefore most effectively implemented as a targeted unit operation within an integrated treatment train rather than as a universal replacement for conventional treatment.

5. Published October 1, 2026

   Other

   Fabrication of High Performance Catalysts by Controlled Flow Cavitation

   Controlled flow cavitation (CFC) is evaluated as a process intensification method for the synthesis and conditioning of high performance catalyst materials. The method couples rapid precipitation or reduction with pressure driven cavitation so that micromixing, bubble collapse, shear, microjet impact, fragmentation, interfacial renewal, and transient thermal effects act on reactive intermediates before extensive aging. This article integrates hydrodynamic and materials frameworks for interpreting catalyst formation, including pressure and velocity relations, cavitation number, bubble dynamics, hydraulic energy, residence time, micromixing, supersaturation, nucleation, and diffraction based structural metrics. Reported CFC results are reviewed for perovskites, copper-zinc-aluminum oxides, cobalt molybdate, supported gold, silver, platinum, bismuth molybdate, titania, lead zirconate titanate, nanocalcite, nano ZnO, iron oxide, and catalyst slurries. The evidence indicates that CFC can improve phase homogeneity, control crystallite and agglomerate size, modify microstrain, and increase dispersion in selected systems, but responses are often nonmonotonic and strongly coupled to precursor chemistry, pressure recovery, solids loading, residence history, washing, drying, and activation. Structural improvement does not by itself establish catalytic improvement; active state characterization, intrinsic kinetics, selectivity, stability, and transport controls remain necessary. Experimental design, scale up, process analytical technology, safety, erosion, energy, and product equivalence requirements are also defined. Scale up should preserve material forming history and active state performance rather than nominal pressure or cavitation number alone.

6. Published October 1, 2026

   Updated October 1, 2026

   Industrial applications

   Vegetable Oil Refining, Biodiesel, and Oleochemical Conversion

   Hydrodynamic cavitation can intensify vegetable oil refining, biodiesel production, and oleochemical conversion by coupling transient pressure reduction and recovery with droplet breakup, boundary layer renewal, micromixing, deagglomeration, and controlled hydraulic energy dissipation. This article examines feedstock composition, conventional process boundaries, reactor configurations, transport mechanisms, and integration into water, acid, and enzymatic degumming, alkali neutralization, washing, bleaching, biodiesel transesterification, high free fatty acid esterification, hydrolysis, interesterification, and soapstock acidulation. Governing relations for continuity, mechanical energy, cavitation number, Reynolds number, bubble dynamics, interfacial area, mass transfer, droplet breakup, residence time, reaction kinetics, energy demand, material balance, and economics are retained and organized within a section based numbering system. Reported patent, vendor, and published data are interpreted with emphasis on analytical comparability and downstream separation. The principal process constraint is the balance between intense contact and phase disengagement: hydraulic dose must be sufficient to reduce transport limitations while avoiding persistent emulsions, oxidation, excessive heating, methanol flashing, erosion, plugging, pump cavitation, and separator overload. Scale up should preserve a product relevant operating window defined by pressure recovery, residence distribution, specific energy, temperature, interfacial response, reaction behavior, and separator loading. Verification requires closed material balances, synchronized sampling, complete product analysis, equipment condition monitoring, and site specific economic assessment.

7. Published October 1, 2026

   Industrial applications

   Hydrodynamic Cavitation in Pharmaceutical Particle Engineering, Crystallization, and Drug Delivery

   Hydrodynamic cavitation and fixed geometry high pressure microchannel processing provide intensive methods for controlling pharmaceutical particles, crystals, emulsions, and lipid vesicles. This article examines the relationships among pressure history, cavitation, energy dissipation, residence time, particle fracture, crystallization, surface stabilization, and critical quality attributes. Top down size reduction, bottom up crystallization, cavitation assisted processing, and liposome manufacture are evaluated using representative data for active pharmaceutical ingredient suspensions, naproxen crystallization, emulsions, nanosuspensions, and liposomal systems. The analysis emphasizes that median particle size alone is insufficient for process assessment. Distribution width and coarse tail, morphology, solid state, encapsulation efficiency, free drug, release, storage stability, contamination, sterility, and equipment condition must also be controlled. Performance depends on pressure and back pressure, pass history, chamber geometry, formulation composition, temperature, dissolved gas, and stabilizer coverage. Scale up should preserve the local processing mechanism and hydraulic history rather than pump pressure alone. A Quality by Design framework integrating orthogonal characterization, process analytical technology, cleaning, wear monitoring, and lifecycle validation is presented for development and manufacturing.

8. Published October 1, 2026

   Industrial applications

   Hydrodynamic Cavitation in Food and Fermentation Processing

   Hydrodynamic cavitation is an intensification technology that couples rapid pressure variation, cavity growth and collapse, turbulence, interfacial renewal, particle disruption, gas dispersion, and hydraulic energy dissipation within compact flow equipment. This article examines its application to food and fermentation processing, with emphasis on beer brewing, fruit and vegetable juices, dairy products, liquid egg, ice cream, mayonnaise and salad dressing, protein processing, bioproduct recovery, and dry mill corn ethanol production. The analysis relates product response to cavitation number, pressure history, specific energy, residence time, pass frequency, temperature, rheology, gas content, particle or droplet size distribution, and downstream holding or separation. Reported studies show that cavitation can intensify extraction, homogenization, powder hydration, emulsification, starch accessibility, protein functionalization, fermentation pretreatment, and combined thermal and mechanical processing. The same mechanisms can also cause overprocessing, oxidation, protein damage, persistent emulsions, excess fines, erosion, or reduced separation efficiency. Microbial and enzyme control therefore require product specific validation rather than reliance on pressure or visible cavitation alone. Scale up should preserve the mechanism governing the critical quality attribute and should include sanitary design, residence time distribution, thermal and energy balances, cleanability, wear control, and matched process economics. The evidence supports hydrodynamic cavitation as a versatile platform when operating conditions are selected from product quality and process performance requirements.

9. Published October 1, 2026

   Industrial applications

   Emerging Frontiers in Hydrodynamic Cavitation

   Hydrodynamic cavitation is increasingly applied as a multifunctional process intensification method in systems where pressure reduction, bubble generation, interfacial renewal, collapse, and repeated hydraulic exposure can be exploited for different engineering objectives. This article evaluates emerging applications in cooling water conditioning, commercial aquatic systems, aeration, flotation, gas stripping, biomass lysis and extraction, petroleum processing, critical mineral recovery, cavitating jet cleaning, and drilling. The analysis distinguishes collapse dominated treatment from stable cavity and microbubble regimes and emphasizes that pressure drop alone does not define process severity. For each application, the relevant mechanism, performance metric, downstream separation requirement, scale up variable, and principal failure mode are identified. Reviewed evidence shows that cavitation can intensify bulk crystallization, oxygen transfer, fine particle flotation, degassing, mass transfer, surface cleaning, and rock weakening when the hydraulic state is matched to the required function. The same mechanisms can also cause erosion, fragmentation, gas redissolution, contaminant release, excessive fines, or unproductive energy consumption. Scale up therefore requires preservation of both local cavitation behavior and system exposure, together with measured flow, pressure, temperature, gas fraction, power, wear, and application specific response. The most defensible design approach is function first: define the required physical effect, integrate cavitation with the necessary separation and control operations, and validate performance under realistic feed variability and extended operation.

10. Published October 1, 2026

    Reactors & equipment

    Cavitation Driven Exfoliation of Graphene and Two Dimensional Materials

    Cavitation assisted liquid phase exfoliation provides a scalable top down route for producing graphene and other two dimensional materials without necessarily relying on strong oxidative chemistry. This article examines the thermodynamic basis of layer separation, liquid wetting and stabilization, cavitation physics, stress transfer to layered particles, and the operating characteristics of acoustic and hydrodynamic reactors. Jet cavitation, microfluidic cavitation, rapid decompression, microfluidization, wet jet milling, rotor stator processing, and hybrid routes are evaluated together with downstream classification, concentration, drying, formulation, and quality assurance. Published evidence shows that useful exfoliation requires a controlled balance between delamination and damage. Increasing treatment severity can reduce thickness but can also decrease lateral size, increase edge density and basal plane defects, generate holes, accelerate stabilizer degradation, increase equipment wear, and reduce isolated yield. Product quality therefore cannot be defined by a single metric. Raman spectroscopy, AFM, TEM, surface chemistry, trace contamination, dispersion stability, mass balance, and application performance must be interpreted together. Scale up should preserve effective exposure, pressure recovery, residence time distribution, solids loading, thermal history, and classification conditions rather than equipment size or nominal power alone. The same framework extends to boron nitride, transition metal dichalcogenides, black phosphorus, layered oxides, MXenes, and clays. Cavitation is most effective when it is integrated into specification driven manufacturing and evaluated by reproducible mass of in specification product per unit time, energy, and process burden.

11. Published October 1, 2026

    Reactors & equipment

    Cavitation-Assisted Particle Dispersion

    Hydrodynamic cavitation provides a media-free route for particle dispersion, deagglomeration, controlled comminution, and exfoliation by combining extensional flow, viscous and turbulent stresses, bubble-induced particle motion, liquid microjets, shock waves, and high-velocity interparticle interactions. This article develops an engineering framework that links particulate structure, colloidal stability, cavitation dynamics, local stress scales, cumulative exposure, and process equipment to measurable product attributes. The analysis distinguishes reversible deagglomeration from aggregate or primary-particle fracture and emphasizes control of the coarse tail of the particle-size distribution, rheology, morphology, crystal structure, chemical purity, and aged stability. Quantitative case studies covering metal oxides, silver, nanofluids, pharmaceuticals, soy slurries, silicon, graphite, carbon nanotubes, resins, and plant raw materials demonstrate strong first-pass effects, formulation-dependent endpoints, and the risk of overprocessing. Practical scale-up is based on preserving critical pressure history and passage geometry, controlling residence-time and pass distributions, managing heat and erosion, and increasing throughput by parallelization or staged processing. The appropriate endpoint is therefore the minimum cavitation severity and cumulative exposure that achieve a stable particle-size distribution while preserving the properties required by the final application.

12. Published October 1, 2026

    Reactors & equipment

    Calculations of Hydrodynamic Cavitation Devices

    Hydrodynamic cavitation devices generate controlled vapor and gas vapor cavities by imposing a local pressure depression followed by pressure recovery. Reliable design therefore requires more than a single cavitation threshold or dimensionless index. This article presents a calculation framework for static, vortex, and dynamic hydrodynamic cavitation devices and integrates hydraulic sizing, pressure reference selection, dimensionless analysis, energy input, residence time, cavity collapse, uncertainty, mechanical integrity, materials selection, scale translation, and commissioning. Static device calculations address orifices, nozzles, slits, Venturi passages, bluff bodies, and multistage arrangements. Vortex device calculations combine tangential inlet sizing with radial equilibrium screening and finite core limitations. Dynamic device calculations include rotor tip speed, rotational Reynolds number, cavitation number, power number, torque, rotor stator clearance, feature passage frequency, stress, vibration, and thermal growth. Worked examples demonstrate preliminary sizing for an eight hole orifice plate, an ideal Venturi throat, a finite core vortex chamber, and a rotor stator operating point. The analysis emphasizes that local pressure history, cavity structure, process response, and erosion cannot be inferred reliably from global pressure drop alone. Calibrated coefficients, validated computational fluid dynamics, representative pilot testing, and measured operating maps are required to establish a defensible design envelope and service life.

13. Published September 29, 2026

    Other

    Performance considerations in stator selection for high shear rotor-stator mixers

    Stator geometry is a primary process variable in high shear rotor-stator mixing because it governs hydraulic restriction, discharge area, local velocity gradients, and the frequency of shear generating passage events. These effects directly influence pumping capacity, pressure drop, energy dissipation, recirculation, solids tolerance, fouling tendency, and final dispersion quality. This article reviews the process implications of common stator geometries, including coarse disintegrating, square hole, slotted, fine screen, and multistage or toothed heads. Stator selection should therefore be treated as a first order engineering decision tied to process objective, rheology, and scale up path.

14. Published September 29, 2026

    Reactors & equipment

    The Rise of Life on Earth: Cavitation in Nature

    The phenomenon of cavitation has been known in science and technology for more than a hundred years. It was first recognized as an important hydrodynamic phenomenon in connection with high speed marine propulsion, including early observations associated with British destroyers in the late nineteenth century. Osborne Reynolds and later researchers helped establish cavitation as a serious problem in ship propellers, pumps, and turbines [1,2].

15. Published September 29, 2026

    Fundamentals

    Single Cavitation Bubble Collapse: Phenomena, Theoretical Models, and Thermodynamic Effects

    The collapse of a single cavitation bubble is a fundamental hydrodynamic event in which pressure work is concentrated into rapid liquid motion, compression of the bubble contents, shock emission, jet formation, rebound, heat transfer, and phase change. This article reviews the principal collapse phenomena, the governing theoretical models, and the thermodynamic mechanisms that modify bubble dynamics. Classical Rayleigh and Rayleigh Plesset formulations establish the inertial collapse scale, whereas Keller Miksis, Gilmore, and Prosperetti Lezzi equations account for liquid compressibility with increasing physical detail. Boundary integral formulations and compressible multiphase computational fluid dynamics extend the analysis to nonspherical collapse, jet penetration, topology change, and local wall loading. Particular attention is given to thermodynamic feedback caused by evaporation, condensation, latent heat exchange, and temperature dependent saturation pressure. Experimental observations in water, aqueous ammonia, and liquid nitrogen demonstrate that increased vapor content and finite rate phase change can increase minimum bubble radius, reduce collapse velocity, weaken shock and jet intensity, and alter rebound and stability. The analysis emphasizes that model selection must be tied to the required observable and that validation against radius history alone is insufficient when energy partition, peak pressure, interfacial temperature, or material loading is of interest.

16. Published September 29, 2026

    Fundamentals

    Physical Basis of Hydrodynamic Cavitation Generation

    Hydrodynamic cavitation is generated when flow acceleration or vortical motion reduces local static pressure sufficiently to permit the formation of vapor and gas cavities, followed by pressure recovery and collapse. This article examines the physical basis of cavitation inception and hydrodynamic generation, with emphasis on conservation of flow, mechanical energy balance, cavitation number, pressure recovery, liquid properties, and the role of nuclei. The principal families of static and dynamic cavitation devices are compared, including orifice plates, multihole plates, Venturi restrictions, vortex chambers, rotor stator systems, and multistage baffles. The analysis shows that cavitation intensity cannot be characterized by pressure drop or cavitation number alone. Collapse behavior also depends on downstream pressure recovery, gas content, temperature, viscosity, interfacial tension, residence time, void fraction, and cavity transport. Collective cloud behavior further limits the applicability of single bubble descriptions. A physically meaningful engineering assessment therefore requires explicit definition of reference pressures and velocities together with complementary dimensionless groups and process performance metrics. These considerations provide a consistent framework for comparing cavitation devices, identifying operating regimes, and controlling the location and intensity of cavity collapse.

17. Published September 29, 2026

    Reactors & equipment

    Hydrodynamic Cavitation Technological Equipment

    Hydrodynamic cavitation equipment intentionally generates controlled low pressure regions and subsequent pressure recovery so that cavity growth and collapse can be used for process intensification. This article examines the hydraulic, mechanical, and process design of static and dynamic cavitation systems, including orifice, Venturi, bluff body, vortex, multistage, opposed flow, rotor stator, pinned disc, cavity rotor, and high pressure interaction architectures. The principal hydrodynamic quantities governing equipment comparison are summarized through continuity, pressure balance, cavitation number, Reynolds number, Euler number, Weber number, Strouhal number, and rotating equipment similarity parameters. Representative commercial systems are reviewed with emphasis on operating envelope, pressure control, cleanability, erosion, flow distribution, temperature management, energy accounting, and product qualification. Hydraulic power, shaft power, and measured electrical input are distinguished to establish a consistent basis for specific energy and thermal balance. Scale up is treated as preservation of the local geometry, pressure history, collapse environment, exposure distribution, residence time, and product response rather than geometric enlargement alone. Reproducible hydrodynamic cavitation processing therefore requires complete reporting of device geometry, pressure reference locations, flow conditions, gas state, temperature history, energy boundary, product response, and equipment integrity. When validated local cavitation conditions cannot be maintained in a larger unit, parallel scale out provides a conservative alternative for increasing throughput.

18. Published September 29, 2026

    Reactors & equipment

    Cavitation in Hydraulic Machinery, Valves, Piping, and Marine Systems

    Cavitation is a multiphase flow phenomenon produced when local liquid pressure reaches or falls below the saturation vapor pressure and the resulting vapor structures subsequently collapse or persist according to the downstream pressure field. This article examines cavitation in rotodynamic pumps, control valves and piping systems, marine propulsors, hydrofoils, and hydraulic turbines. The discussion integrates net positive suction head, pressure recovery, cavitation indices, liquid choking, unsteady loading, erosion, noise, vibration, and performance degradation with practical diagnostic and mitigation methods. Particular emphasis is placed on distinguishing the location of vapor formation from the location of collapse, because damage may occur downstream or away from the apparent inception site. System pressure, local velocity, equipment geometry, operating envelope, materials, coatings, and verification methods are treated as coupled engineering variables. The resulting framework supports mechanism based assessment and selection of preventive measures across hydraulic and marine applications.

19. Published September 29, 2026

    Reactors & equipment

    Anti-Cavitation Control Valves

    Cavitation in liquid control valves results from local pressure reduction below vapor pressure followed by vapor collapse during pressure recovery. The associated microjets, pressure waves, vibration, and unsteady hydraulic forces can cause trim erosion, pressure boundary damage, noise, loss of control authority, and reduced service life. This article presents a unified engineering treatment of cavitation physics, liquid valve sizing parameters, pressure recovery behavior, and anti-cavitation trim architecture. The discussion relates cavitation indices and liquid choking criteria to practical design strategies, including staged pressure reduction, opposed jet bubble isolation, stacked disk and concentric sleeve trims, axial multistage geometries, multipath trims, dirty service configurations, and fixed energy dissipators. Material selection, seat protection, outlet velocity, actuator stability, solids tolerance, and system layout are examined as coupled design variables. Application considerations are summarized for water distribution, power generation, oil and gas, petrochemical, and low flow injection services. A worked sizing example demonstrates preliminary severity assessment, choked flow capacity, stage count estimation, and hydraulic power dissipation. The article also reviews field diagnosis, maintenance, computational fluid dynamics, patent development, topology optimization, and additive manufacturing. Final valve selection should be based on the complete operating envelope and tested coefficients for the specific valve and trim geometry. Keywords: cavitation; control valves; anti-cavitation trim; pressure staging; liquid choking; valve sizing; severe service.