All Outputs (23)

The microlayer and force balance of bubbles growing on solid in nucleate boiling (2024)
Journal Article
Zhang, X., El Mellas, I., Andreini, N., & Magnini, M. (2025). The microlayer and force balance of bubbles growing on solid in nucleate boiling. International Journal of Multiphase Flow, 183, Article 105049. https://doi.org/10.1016/j.ijmultiphaseflow.2024.105049

This study uses interface-resolved computational fluid dynamics simulations to investigate the dynamics of bubble growth on a horizontal solid surface, with a focus on the characteristics of the microlayer and the forces involved in the process. The... Read More about The microlayer and force balance of bubbles growing on solid in nucleate boiling.

Predicting initial microlayer thickness in nucleate boiling using Landau–Levich theory (2024)
Journal Article
Zhang, X., Mellas, I. E., & Magnini, M. (2024). Predicting initial microlayer thickness in nucleate boiling using Landau–Levich theory. Journal of Fluid Mechanics, 997, Article A44. https://doi.org/10.1017/jfm.2024.559

A phenomenological model is proposed to estimate the initial thickness of the liquid microlayer forming beneath a vapour bubble growing on a solid surface upon nucleate boiling. The model employs an analogy between the microlayer formation and the cl... Read More about Predicting initial microlayer thickness in nucleate boiling using Landau–Levich theory.

Non-negligible buoyancy effect on bubbles travelling in horizontal microchannels of comparable size at small Bond numbers (2024)
Journal Article
Cranmer, J. A., Sharaborin, E., Khodaparast, S., Giustini, G., & Magnini, M. (2024). Non-negligible buoyancy effect on bubbles travelling in horizontal microchannels of comparable size at small Bond numbers. International Journal of Multiphase Flow, 181, Article 105019. https://doi.org/10.1016/j.ijmultiphaseflow.2024.105019

When a gas bubble is transported by a liquid flow confined within a horizontal channel of comparable size, buoyancy effects are usually assumed to be negligible if the Bond number of the flow is less than unity. However, recent experimental studies s... Read More about Non-negligible buoyancy effect on bubbles travelling in horizontal microchannels of comparable size at small Bond numbers.

Numerical modelling of flow boiling inside microchannels: A critical review of methods and applications (2024)
Journal Article
Darshan, M. B., Magnini, M., & Matar, O. K. (2024). Numerical modelling of flow boiling inside microchannels: A critical review of methods and applications. Applied Thermal Engineering, 257(Part C), Article 124464. https://doi.org/10.1016/j.applthermaleng.2024.124464

Boiling heat transfer in microchannels has been a very hot topic in heat transfer research over the past two decades, fuelled by the dramatic need for high heat flux cooling of miniaturised electronics and a number of high energy density applications... Read More about Numerical modelling of flow boiling inside microchannels: A critical review of methods and applications.

Annular two-phase flow in a small diameter tube: OpenFOAM simulations with turbulence damping vs optical measurements (2024)
Journal Article
Zanetti, E., Berto, A., Bortolin, S., Magnini, M., & Del Col, D. (2024). Annular two-phase flow in a small diameter tube: OpenFOAM simulations with turbulence damping vs optical measurements. International Journal of Thermofluids, 24, Article 100871. https://doi.org/10.1016/j.ijft.2024.100871

In this work, numerical simulations are performed to predict two-phase annular flow of refrigerant R245fa inside a 3.4 mm diameter vertical channel. The VOF (Volume of Fluid) method implemented in an OpenFOAM solver is used to accurately track the va... Read More about Annular two-phase flow in a small diameter tube: OpenFOAM simulations with turbulence damping vs optical measurements.

A hybrid atomistic-continuum framework for multiscale simulations of boiling (2024)
Presentation / Conference Contribution
Gennari, G., Smith, E. R., Pringle, G. J., & Magnini, M. (2024, June). A hybrid atomistic-continuum framework for multiscale simulations of boiling. Presented at 9th European Thermal Sciences Conference (Eurotherm 2024), Lake Bled, Slovenia

Boiling is a multiscale physics process where the nucleation of vapour bubbles occurs due to molecular-scale interactions between the fluid and a heated wall, but it also depends on the larger-scale hydrodynamics and thermal boundary layers determine... Read More about A hybrid atomistic-continuum framework for multiscale simulations of boiling.

Hydrodynamic characteristics of the microlayer under vapour bubbles on solid surfaces (2024)
Presentation / Conference Contribution
Zhang, X., Mellas, I. E., & Magnini, M. (2024, June). Hydrodynamic characteristics of the microlayer under vapour bubbles on solid surfaces. Presented at 9th European Thermal Sciences Conference (Eurotherm 2024), Lake Bled, Slovenia

This study investigates the hydrodynamic behaviour of the microlayer, a thin liquid film of a few micrometres thickness that forms beneath vapour bubbles during boiling under specific conditions. This microlayer serves as a rapid heat transfer medium... Read More about Hydrodynamic characteristics of the microlayer under vapour bubbles on solid surfaces.

Study of turbulent wavy annular flow inside a 3.4 mm diameter vertical channel by using the Volume of Fluid method in OpenFOAM (2024)
Presentation / Conference Contribution
Zanetti, E., Berto, A., Bortolin, S., Magnini, M., & Del Col, D. (2024, June). Study of turbulent wavy annular flow inside a 3.4 mm diameter vertical channel by using the Volume of Fluid method in OpenFOAM. Presented at 9th European Thermal Sciences Conference (Eurotherm 2024), Lake Bled, Slovenia

In annular downward flow, an annular liquid film flows at the perimeter of the channel pushed down by the gravity force and by the shear stress that the vapor core exerts on it. Depending on the working conditions, the vapor-liquid interface can be f... Read More about Study of turbulent wavy annular flow inside a 3.4 mm diameter vertical channel by using the Volume of Fluid method in OpenFOAM.

Numerical investigation of bubble dynamics and flow boiling heat transfer in cylindrical micro-pin-fin heat exchangers (2024)
Journal Article
El Mellas, I., Samkhaniani, N., Falsetti, C., Stroh, A., Icardi, M., & Magnini, M. (2024). Numerical investigation of bubble dynamics and flow boiling heat transfer in cylindrical micro-pin-fin heat exchangers. International Journal of Heat and Mass Transfer, 228, Article 125620. https://doi.org/10.1016/j.ijheatmasstransfer.2024.125620

Micro-pin-fin evaporators are a promising alternative to multi-microchannel heat sinks for two-phase cooling of high power-density devices. Within pin-fin evaporators, the refrigerant flows through arrays of obstacles in cross-flow and is not restric... Read More about Numerical investigation of bubble dynamics and flow boiling heat transfer in cylindrical micro-pin-fin heat exchangers.

Coupled atomistic–continuum simulations of nucleate boiling (2024)
Journal Article
Gennari, G., Smith, E. R., Pringle, G. J., & Magnini, M. (2024). Coupled atomistic–continuum simulations of nucleate boiling. International Journal of Thermal Sciences, 200, Article 108954. https://doi.org/10.1016/j.ijthermalsci.2024.108954

Boiling is a striking example of a multiscale process, where the dynamics of bubbles is governed by the interplay between the molecular interactions responsible for nucleation, and the macroscale hydrodynamic and thermal boundary layers. A complete d... Read More about Coupled atomistic–continuum simulations of nucleate boiling.

Understanding Inconsistencies in Thermohydraulic Characteristics Between Experimental and Numerical Data for DI Water Flow Through a Rectangular Microchannel (2024)
Journal Article
Schepperle, M., Samkhaniani, N., Magnini, M., Woias, P., & Stroh, A. (2024). Understanding Inconsistencies in Thermohydraulic Characteristics Between Experimental and Numerical Data for DI Water Flow Through a Rectangular Microchannel. ASME Journal of Heat and Mass Transfer, 146(3), Article 031801. https://doi.org/10.1115/1.4064330

Facing discrepancies between numerical simulation, experimental measurement, and theory is common in studies of fluid flow and heat transfer in microchannels. The cause of these discrepancies is often linked to the transition from the macroscale to t... Read More about Understanding Inconsistencies in Thermohydraulic Characteristics Between Experimental and Numerical Data for DI Water Flow Through a Rectangular Microchannel.

An experimental investigation of the effect of surface roughness on sessile droplet evaporation (2023)
Presentation / Conference Contribution
Zhang, Z., Yan, Y., & Magnini, M. (2023, August). An experimental investigation of the effect of surface roughness on sessile droplet evaporation. Presented at International Heat Transfer Conference 17, Cape Town, South Africa

As one of the most common phenomena in nature, droplet evaporation has become a major heat transfer mode and is used widely in industries and scientific fields. For a sessile droplet, the wettability of the substrate surface could make a significant... Read More about An experimental investigation of the effect of surface roughness on sessile droplet evaporation.

Dynamics of long bubbles propagating through cylindrical micro-pin fin arrays (2023)
Journal Article
El Mellas, I., Municchi, F., Icardi, M., & Magnini, M. (2023). Dynamics of long bubbles propagating through cylindrical micro-pin fin arrays. International Journal of Multiphase Flow, 163, 104443. https://doi.org/10.1016/j.ijmultiphaseflow.2023.104443

The dynamics of two-phase flows confined within complex and non-straight geometries is of interest for a variety of applications such as micro-pin fin evaporators and flow in unsaturated porous media. Despite the propagation of bubbles in straight ch... Read More about Dynamics of long bubbles propagating through cylindrical micro-pin fin arrays.

Conjugate heat transfer effects on flow boiling in microchannels (2022)
Journal Article
Municchi, F., El Mellas, I., Matar, O. K., & Magnini, M. (2022). Conjugate heat transfer effects on flow boiling in microchannels. International Journal of Heat and Mass Transfer, 195, Article 123166. https://doi.org/10.1016/j.ijheatmasstransfer.2022.123166

This article presents a computational study of saturated flow boiling in non-circular microchannels. The unit channel of a multi-microchannel evaporator, consisting of the fluidic channel and surrounding evaporator walls, is simulated and the conjuga... Read More about Conjugate heat transfer effects on flow boiling in microchannels.

Stochastic design for additive manufacture of true biomimetic populations (2022)
Journal Article
Groth, J.-H., Magnini, M., Tuck, C., & Clare, A. (2022). Stochastic design for additive manufacture of true biomimetic populations. Additive Manufacturing, 55, Article 102739. https://doi.org/10.1016/j.addma.2022.102739

Current biomimetic designs do not incorporate naturally occurring variance. Instead, the same unit cell is repeatedly copied and pasted to create a pattern. Existing stochastic designs use the same randomness for all parameters. However, nature teach... Read More about Stochastic design for additive manufacture of true biomimetic populations.

Liquid film distribution around long gas bubbles propagating in rectangular capillaries (2022)
Journal Article
Magnini, M., Municchi, F., El Mellas, I., & Icardi, M. (2022). Liquid film distribution around long gas bubbles propagating in rectangular capillaries. International Journal of Multiphase Flow, 148, Article 103939. https://doi.org/10.1016/j.ijmultiphaseflow.2021.103939

We present a systematic analysis of the bubble and liquid film dynamics corresponding to the propagation of long, isolated gas bubbles, within rectangular capillary channels of cross-sectional aspect-ratio ranging from 1 to 8. Direct numerical simula... Read More about Liquid film distribution around long gas bubbles propagating in rectangular capillaries.

Five simple tools for stochastic lattice creation (2021)
Journal Article
Groth, J. H., Anderson, C., Magnini, M., Tuck, C., & Clare, A. (2022). Five simple tools for stochastic lattice creation. Additive Manufacturing, 49, Article 102488. https://doi.org/10.1016/j.addma.2021.102488

Lattices are increasingly used in engineering applications. They can reduce weight in aircraft components, increase the efficiency of heat exchangers and are used as medical implants. Typically a regular and graded lattice, where the unit cells are i... Read More about Five simple tools for stochastic lattice creation.

Dynamics of long gas bubbles rising in a vertical tube in a cocurrent liquid flow (2019)
Journal Article
Magnini, M., Khodaparast, S., Matar, O. K., Stone, H. A., & Thome, J. R. (2019). Dynamics of long gas bubbles rising in a vertical tube in a cocurrent liquid flow. Physical Review Fluids, 4(2), Article 023601. https://doi.org/10.1103/PhysRevFluids.4.023601

© 2019 American Physical Society. When a confined long gas bubble rises in a vertical tube in a cocurrent liquid flow, its translational velocity is the result of both buoyancy and mean motion of the liquid. A thin film of liquid is formed on the tub... Read More about Dynamics of long gas bubbles rising in a vertical tube in a cocurrent liquid flow.

Numerical analysis of slug flow boiling in square microchannels (2018)
Journal Article
Ferrari, A., Magnini, M., & Thome, J. R. (2018). Numerical analysis of slug flow boiling in square microchannels. International Journal of Heat and Mass Transfer, 123, 928-944. https://doi.org/10.1016/j.ijheatmasstransfer.2018.03.012

© 2018 Elsevier Ltd Boiling heat transfer in micro-geometries has been studied extensively in the recent years as an efficient heat removal mechanism. Numerical simulations have been traditionally employed to resolve the small spatial and temporal sc... Read More about Numerical analysis of slug flow boiling in square microchannels.

Pore-scale analysis of the minimum liquid film thickness around elongated bubbles in confined gas-liquid flows (2017)
Journal Article
Magnini, M., Beisel, A. M., Ferrari, A., & Thome, J. R. (2017). Pore-scale analysis of the minimum liquid film thickness around elongated bubbles in confined gas-liquid flows. Advances in Water Resources, 109, 84-93. https://doi.org/10.1016/j.advwatres.2017.08.020

© 2017 Elsevier Ltd The fluid mechanics of elongated bubbles in confined gas-liquid flows in micro-geometries is important in pore-scale flow processes for enhanced oil recovery and mobilization of colloids in unsaturated soil. The efficiency of such... Read More about Pore-scale analysis of the minimum liquid film thickness around elongated bubbles in confined gas-liquid flows.