Hossein Hamzehpour
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Hossein Hamzehpour has a total of 36 co-authors. Here are the top co-authors by number of shared publications:
- Mohammad Alidoust
Department of Physics K.N Toosi University of Technology 15875-4416 Tehran Iran
5 shared publications Muhammad Sahimi
Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089-1211, USA
5 shared publications- Elham Sharafedini
K. N. Toosi University of Technology
4 shared publications - Jalal Sarabadani
School of Quantum Physics and Matter Institute for Research in Fundamental Sciences (IPM) Tehran 19538‐33511 Iran
4 shared publications - S. M. Kazem Manzoorolajdad
Department of Physics K.N Toosi University of Technology 15875-4416 Tehran Iran
3 shared publications M. Samadpour
Department of Physics, K.N. Toosi University of Technology, Tehran, Iran
2 shared publications
Latest Publications
- Open Access
- 1 April 2026
- Published by AIP Publishing in Physics of Fluids
- Vol. 38 (4)
Geometry-driven segregation in periodically textured microfluidic channels
We investigate the transport dynamics of elongated microparticles in microchannel flows. While smooth-walled channels preserve the dependence of particle trajectories on initial orientation and lateral position, we show that introducing periodically textured walls can trigger robust alignment of the particle along the channel centerline. This geometry-driven alignment arises from repeated reorientations generated by spatially modulated shear gradients near the textured walls. The alignment efficiency depends on particle elongation and the relative texture wavelength, with an optimal range for the maximal effect. While the observed alignment behavior is not limited to low Reynolds numbers, the characteristic alignment length scale diverges as the Reynolds number increases toward the turbulent flow regime. These findings offer a predictive framework for designing microfluidic devices that passively sort or focus anisotropic particles, with implications for soft matter transport, biophysical flows, and microfluidic engineering.
- 1 April 2026
- Published by AIP Publishing in Physics of Fluids
- Vol. 38 (4)
Open AccessGeometry-driven segregation in periodically textured microfluidic channels
We investigate the transport dynamics of elongated microparticles in microchannel flows. While smooth-walled channels preserve the dependence of particle trajectories on initial orientation and lateral position, we show that introducing periodically textured walls can trigger robust alignment of the particle along the channel centerline. This geometry-driven alignment arises from repeated reorientations generated by spatially modulated shear gradients near the textured walls. The alignment efficiency depends on particle elongation and the relative texture wavelength, with an optimal range for the maximal effect. While the observed alignment behavior is not limited to low Reynolds numbers, the characteristic alignment length scale diverges as the Reynolds number increases toward the turbulent flow regime. These findings offer a predictive framework for designing microfluidic devices that passively sort or focus anisotropic particles, with implications for soft matter transport, biophysical flows, and microfluidic engineering.
- 24 September 2025
- Published by American Physical Society (APS) in Physical Review E
- Vol. 112 (3) , 034128
Quantum transport in random alloys with intermetallic needle-shape precipitates
Employing Monte Carlo sampling and a self-consistent multiscale numerical approach, we obtain a parametric simple formula for the effective electrical charge conductivity of composite systems containing randomly distributed intermetallic needle-shape precipitates. This formula, derived from extensive fits to computational results, accounts for various experimentally relevant parameters, including the externally applied voltage difference V across the sample, the band gap μ and density ϕ of the precipitates, the density of intermetallic materials, and the orientation of the needle-shape precipitates/order parameter s. Employing this formula, we determine the charge conductance threshold activation functionalities for each parameter versus the other parameters. This parametric formula can serve as a tool for analyzing and designing composite systems.
- 24 September 2025
- Published by American Physical Society (APS) in Physical Review E
- Vol. 112 (3) , 034128
Quantum transport in random alloys with intermetallic needle-shape precipitates
Employing Monte Carlo sampling and a self-consistent multiscale numerical approach, we obtain a parametric simple formula for the effective electrical charge conductivity of composite systems containing randomly distributed intermetallic needle-shape precipitates. This formula, derived from extensive fits to computational results, accounts for various experimentally relevant parameters, including the externally applied voltage difference V across the sample, the band gap μ and density ϕ of the precipitates, the density of intermetallic materials, and the orientation of the needle-shape precipitates/order parameter s. Employing this formula, we determine the charge conductance threshold activation functionalities for each parameter versus the other parameters. This parametric formula can serve as a tool for analyzing and designing composite systems.
- 1 March 2024
- Published by AIP Publishing in Physics of Fluids
- Vol. 36 (3)
Spontaneous rupture of polystyrene clusters trapped by acoustic tweezers: From experimental and simulation point of view
In this research, clusters of 450 μm sized polystyrene particles, suspended in a solution of sodium dodecyl sulfate (SDS), were trapped at nodes of acoustic standing waves. It was observed for the first time that under certain circumstances, the clusters of polystyrene become unstable and start spontaneous ruptures. For further investigation of the mechanism of this phenomenon, the acoustic radiation forces between two polystyrene particles in an acoustic trap were studied using the finite element method (FEM), and it was demonstrated that when the particles go toward the trap and approach each other, after a specific distance, the repulsive acoustic interparticle force dramatically builds up. Finally, when it dominates the primary radiation force, it drives the particles apart. Observations show that by increasing the concentration of SDS in the solution from 0.25 to 3 g/l, the rate of spontaneous ruptures increases, and the clusters disintegrate at smaller radii. The threshold radius of the cluster decreased from 4.29 mm (on average) at 0.5 g/l to 2.8 mm (on average) at 3 g/l. FEM methods justified this observation too. As the concentration of SDS in the fluid increases, the viscosity of the fluid rises. Moreover, simulations indicated that by increasing the viscosity of the fluid, the value of repulsive interparticle force dramatically enhances, and the clusters fall apart more quickly. At the concentration of 1 g/l, however, an unexpected instability was observed in the clusters. Following studies on the zeta potential of the particles at different concentrations showed that this unexpected insatiability of the clusters at this concentration could be attributed to electrostatic repulsion among particles. Zeta potential of the particles in different SDS solutions showed that at this concentration, the net negative charge on the particles is maximum. So, the electrostatic repulsive force intensified the repulsive interparticle force among particles and made the cluster burst at the average radius of 2.63 mm.
- 1 March 2024
- Published by AIP Publishing in Physics of Fluids
- Vol. 36 (3)
Spontaneous rupture of polystyrene clusters trapped by acoustic tweezers: From experimental and simulation point of view
In this research, clusters of 450 μm sized polystyrene particles, suspended in a solution of sodium dodecyl sulfate (SDS), were trapped at nodes of acoustic standing waves. It was observed for the first time that under certain circumstances, the clusters of polystyrene become unstable and start spontaneous ruptures. For further investigation of the mechanism of this phenomenon, the acoustic radiation forces between two polystyrene particles in an acoustic trap were studied using the finite element method (FEM), and it was demonstrated that when the particles go toward the trap and approach each other, after a specific distance, the repulsive acoustic interparticle force dramatically builds up. Finally, when it dominates the primary radiation force, it drives the particles apart. Observations show that by increasing the concentration of SDS in the solution from 0.25 to 3 g/l, the rate of spontaneous ruptures increases, and the clusters disintegrate at smaller radii. The threshold radius of the cluster decreased from 4.29 mm (on average) at 0.5 g/l to 2.8 mm (on average) at 3 g/l. FEM methods justified this observation too. As the concentration of SDS in the fluid increases, the viscosity of the fluid rises. Moreover, simulations indicated that by increasing the viscosity of the fluid, the value of repulsive interparticle force dramatically enhances, and the clusters fall apart more quickly. At the concentration of 1 g/l, however, an unexpected instability was observed in the clusters. Following studies on the zeta potential of the particles at different concentrations showed that this unexpected insatiability of the clusters at this concentration could be attributed to electrostatic repulsion among particles. Zeta potential of the particles in different SDS solutions showed that at this concentration, the net negative charge on the particles is maximum. So, the electrostatic repulsive force intensified the repulsive interparticle force among particles and made the cluster burst at the average radius of 2.63 mm.
- 24 February 2024
- Published by Springer Nature in Microfluidics and Nanofluidics
- Vol. 28 (3) , 1-10
Molecular dynamics study of electro-osmotic flow in a nanochannel with molybdenum disulfide walls
- 24 February 2024
- Published by Springer Nature in Microfluidics and Nanofluidics
- Vol. 28 (3) , 1-10
Molecular dynamics study of electro-osmotic flow in a nanochannel with molybdenum disulfide walls
- Open Access
Electroosmotic Flow in Different Phosphorus Nanochannels
The electrokinetic transport in a neutral system consists of an aqueous NaCl solution confined in a nanochannel with two similar parallel phosphorene walls, and is investigated for different black, blue, red, and green phosphorene allotropes in the presence of an external electric field in the directions $x$ (parallel to the walls roughness axis) and $y$ (perpendicular to the walls roughness axis). The results show that irrespective of the electric field direction, the thickness of the Stern layer increases with the increase in the magnitude of the negative electric surface charge density (ESCD) on the nanochannel walls, and it also increases with the increase in the roughness ratio for different allotropes. Moreover, three different regimes of Debye--Hückel (DH), intermediate, and flow reversal appear as the absolute value of the negative ESCD on the walls grows. With the increase in the absolute value of the negative ESCD, in the DH regime, the flow velocity grows, then in the intermediate regime, it decreases, and finally, at sufficiently high ESCD, the flow reversal occurs. When the external electric field is applied in the $y$ direction, the dynamics of the system are slower than that of the $x$ direction; therefore, the flow reversal occurs at the smaller absolute values of the negative ESCD.Open AccessElectroosmotic Flow in Different Phosphorus Nanochannels
The electrokinetic transport in a neutral system consists of an aqueous NaCl solution confined in a nanochannel with two similar parallel phosphorene walls, and is investigated for different black, blue, red, and green phosphorene allotropes in the presence of an external electric field in the directions $x$ (parallel to the walls roughness axis) and $y$ (perpendicular to the walls roughness axis). The results show that irrespective of the electric field direction, the thickness of the Stern layer increases with the increase in the magnitude of the negative electric surface charge density (ESCD) on the nanochannel walls, and it also increases with the increase in the roughness ratio for different allotropes. Moreover, three different regimes of Debye--Hückel (DH), intermediate, and flow reversal appear as the absolute value of the negative ESCD on the walls grows. With the increase in the absolute value of the negative ESCD, in the DH regime, the flow velocity grows, then in the intermediate regime, it decreases, and finally, at sufficiently high ESCD, the flow reversal occurs. When the external electric field is applied in the $y$ direction, the dynamics of the system are slower than that of the $x$ direction; therefore, the flow reversal occurs at the smaller absolute values of the negative ESCD. - Open Access
Molecular Dynamics Study of Electro-Osmotic Flow in a Nanochannel with Molybdenum Disulfide Walls
The electro-osmotic flow (EOF) in a neutral system consisting of an aqueous NaCl solution confined in a nanochannel with two parallel Molybdenum disulfide ($\textrm{MoS}_{\textrm{2}}$) walls and in the presence of an external electric field parallel to the channel walls, is investigated for the first time. The results indicate that the thickness of the Stern layer grows as the negative electric surface charge density on the nanochannel walls increases. The Stern layer becomes thinner as the salt concentration is increased. Moreover, the EOF occurs under the no-slip condition on the walls. In addition, by increasing the surface charge density the average of the flow velocity across the nanochannel initially grows (Debye--H$\ddot{\textrm{u}}$ckel regime) and reaches its maximum value. Then, by further increasing the surface charge density the water flow rate decreases (intermediate regime), and gets the zero value and becomes negative (reverse flow regime) at even larger values of the surface charge densities. Comparing the results of the previous work wherein the channels are composed of the black phosphorene walls with those of the present study for a channel composed of $\textrm{MoS}_{\textrm{2}}$ surfaces, show that for the latter case the reverse flow occurs at a lower surface charge density and with a greater value of the peak velocity with respect to the change in the surface charge density for the former case.Open AccessMolecular Dynamics Study of Electro-Osmotic Flow in a Nanochannel with Molybdenum Disulfide Walls
The electro-osmotic flow (EOF) in a neutral system consisting of an aqueous NaCl solution confined in a nanochannel with two parallel Molybdenum disulfide ($\textrm{MoS}_{\textrm{2}}$) walls and in the presence of an external electric field parallel to the channel walls, is investigated for the first time. The results indicate that the thickness of the Stern layer grows as the negative electric surface charge density on the nanochannel walls increases. The Stern layer becomes thinner as the salt concentration is increased. Moreover, the EOF occurs under the no-slip condition on the walls. In addition, by increasing the surface charge density the average of the flow velocity across the nanochannel initially grows (Debye--H$\ddot{\textrm{u}}$ckel regime) and reaches its maximum value. Then, by further increasing the surface charge density the water flow rate decreases (intermediate regime), and gets the zero value and becomes negative (reverse flow regime) at even larger values of the surface charge densities. Comparing the results of the previous work wherein the channels are composed of the black phosphorene walls with those of the present study for a channel composed of $\textrm{MoS}_{\textrm{2}}$ surfaces, show that for the latter case the reverse flow occurs at a lower surface charge density and with a greater value of the peak velocity with respect to the change in the surface charge density for the former case. - Open Access
- 23 October 2023
- Published by AIP Publishing in Applied Physics Letters
- Vol. 123 (17)
Statistical quantum conductance of porous and random alloys
Performing statistical evaluations, coupling Schrödinger's equation and Poisson's equation self-consistently, and employing an iterative fitting process, we have obtained a simple parametric formula for the charge conductance of nonmagnetic two-phase porous and random alloys. The formula exhibits remarkable agreement in describing the response of a system to an applied voltage difference, system size, bandgap, and density of conductive grains as parameters. Exploiting the obtained formula, we parametrically determine the activation threshold functionality of each parameter to other parameters where the charge conductance switches “on” and “off.” The results of our study can be directly utilized to guide experiments.
- 23 October 2023
- Published by AIP Publishing in Applied Physics Letters
- Vol. 123 (17)
Open AccessStatistical quantum conductance of porous and random alloys
Performing statistical evaluations, coupling Schrödinger's equation and Poisson's equation self-consistently, and employing an iterative fitting process, we have obtained a simple parametric formula for the charge conductance of nonmagnetic two-phase porous and random alloys. The formula exhibits remarkable agreement in describing the response of a system to an applied voltage difference, system size, bandgap, and density of conductive grains as parameters. Exploiting the obtained formula, we parametrically determine the activation threshold functionality of each parameter to other parameters where the charge conductance switches “on” and “off.” The results of our study can be directly utilized to guide experiments.
- Open Access
- 29 July 2023
- Published by Springer Nature in Scientific Reports
- Vol. 13 (1) , 1-14
Edwards–Wilkinson depinning transition in fractional Brownian motion background
There are various reports about the critical exponents associated with the depinning transition. In this study, we investigate how the disorder strength present in the support can account for this diversity. Specifically, we examine the depinning transition in the quenched Edwards–Wilkinson (QEW) model on a correlated square lattice, where the correlations are modeled using fractional Brownian motion (FBM) with a Hurst exponent of H.We identify a crossover time $$T^*$$ that separates the dynamics into two distinct regimes: for $$T>T^*$$ , we observe the typical behavior of pinned surfaces, while for $$T<T^*$$ , the behavior differs. We introduce a novel three-variable scaling function that governs the depinning transition for all considered H values. The associated critical exponents exhibit a continuous variation with H, displaying distinct behaviors for anti-correlated ( $$H<0.5$$ ) and correlated ( $$H>0.5$$ ) cases. The critical driving force decreases with increasing H, as the host medium becomes smoother for higher H values, facilitating fluid mobility. This fact causes the asymptotic velocity exponent $$\theta$$ to increase monotonically with H.- 29 July 2023
- Published by Springer Nature in Scientific Reports
- Vol. 13 (1) , 1-14
Open AccessEdwards–Wilkinson depinning transition in fractional Brownian motion background
There are various reports about the critical exponents associated with the depinning transition. In this study, we investigate how the disorder strength present in the support can account for this diversity. Specifically, we examine the depinning transition in the quenched Edwards–Wilkinson (QEW) model on a correlated square lattice, where the correlations are modeled using fractional Brownian motion (FBM) with a Hurst exponent of H.We identify a crossover time $$T^*$$ that separates the dynamics into two distinct regimes: for $$T>T^*$$ , we observe the typical behavior of pinned surfaces, while for $$T<T^*$$ , the behavior differs. We introduce a novel three-variable scaling function that governs the depinning transition for all considered H values. The associated critical exponents exhibit a continuous variation with H, displaying distinct behaviors for anti-correlated ( $$H<0.5$$ ) and correlated ( $$H>0.5$$ ) cases. The critical driving force decreases with increasing H, as the host medium becomes smoother for higher H values, facilitating fluid mobility. This fact causes the asymptotic velocity exponent $$\theta$$ to increase monotonically with H. - 1 April 2023
- Published by AIP Publishing in Physics of Fluids
- Vol. 35 (4) , 042006
Electro-osmotic flow in different phosphorus nanochannels
The electrokinetic transport in a neutral system consists of an aqueous NaCl solution confined in a nanochannel with two similar parallel phosphorene walls and is investigated for different black, blue, red, and green phosphorene allotropes in the presence of an external electric field in the directions x (parallel to the walls roughness axis) and y (perpendicular to the walls roughness axis). The results show that irrespective of the electric field direction, the thickness of the Stern layer increases with the increase in the magnitude of the negative electric surface charge density (ESCD) on the nanochannel walls, and it also increases with the increase in the roughness ratio for different allotropes. Moreover, three different regimes of Debye–Hückel (DH), intermediate, and flow reversal appear as the absolute value of the negative ESCD on the walls grows. With the increase in the absolute value of the negative ESCD, in the DH regime, the flow velocity grows, then in the intermediate regime, it decreases, and finally, at sufficiently high ESCD, the flow reversal occurs. When the external electric field is applied in the y direction, the dynamics of the system are slower than that of the x direction; therefore, the flow reversal occurs at the smaller absolute values of the negative ESCD.
- 1 April 2023
- Published by AIP Publishing in Physics of Fluids
- Vol. 35 (4) , 042006
Electro-osmotic flow in different phosphorus nanochannels
The electrokinetic transport in a neutral system consists of an aqueous NaCl solution confined in a nanochannel with two similar parallel phosphorene walls and is investigated for different black, blue, red, and green phosphorene allotropes in the presence of an external electric field in the directions x (parallel to the walls roughness axis) and y (perpendicular to the walls roughness axis). The results show that irrespective of the electric field direction, the thickness of the Stern layer increases with the increase in the magnitude of the negative electric surface charge density (ESCD) on the nanochannel walls, and it also increases with the increase in the roughness ratio for different allotropes. Moreover, three different regimes of Debye–Hückel (DH), intermediate, and flow reversal appear as the absolute value of the negative ESCD on the walls grows. With the increase in the absolute value of the negative ESCD, in the DH regime, the flow velocity grows, then in the intermediate regime, it decreases, and finally, at sufficiently high ESCD, the flow reversal occurs. When the external electric field is applied in the y direction, the dynamics of the system are slower than that of the x direction; therefore, the flow reversal occurs at the smaller absolute values of the negative ESCD.
- 1 March 2023
- Published by AIP Publishing in Physics of Fluids
- Vol. 35 (3) , 031707
Acoustic interaction force between two particles immersed in a viscoelastic fluid
The interaction acoustic radiation force in a standing plane wave applied to each small solid sphere in a two-particle system immersed in a viscoelastic fluid is studied in a framework based on perturbation theory. In this work, the first- and second-order perturbation theories are used in the governing equations with considering the upper-convected Maxwell model to obtain mathematical modeling. We use the finite element method to carry out simulations and describe the behavior of the viscoelastic fluid. The mathematical development is validated from three literature case studies: a one-particle system in a viscous fluid, a two-particle system in a viscous fluid, and a one-particle system in a viscoelastic fluid. The novelty of this study is to establish the acoustic interaction force between two spherical particles immersed in a viscoelastic fluid. The results show that the acoustic interaction force between two spheres is greater in a viscous fluid in comparison with the viscoelastic fluid with the same shear viscosity. This behavior is due to the relaxation time effect. It is also indicated that the acoustic interaction force between the particles decreases by the relaxation time and increases by the fluid's viscosity. A mathematical formula is proposed for the acoustic interaction force between particles located close to each other in a viscoelastic fluid.
- 1 March 2023
- Published by AIP Publishing in Physics of Fluids
- Vol. 35 (3) , 031707
Acoustic interaction force between two particles immersed in a viscoelastic fluid
The interaction acoustic radiation force in a standing plane wave applied to each small solid sphere in a two-particle system immersed in a viscoelastic fluid is studied in a framework based on perturbation theory. In this work, the first- and second-order perturbation theories are used in the governing equations with considering the upper-convected Maxwell model to obtain mathematical modeling. We use the finite element method to carry out simulations and describe the behavior of the viscoelastic fluid. The mathematical development is validated from three literature case studies: a one-particle system in a viscous fluid, a two-particle system in a viscous fluid, and a one-particle system in a viscoelastic fluid. The novelty of this study is to establish the acoustic interaction force between two spherical particles immersed in a viscoelastic fluid. The results show that the acoustic interaction force between two spheres is greater in a viscous fluid in comparison with the viscoelastic fluid with the same shear viscosity. This behavior is due to the relaxation time effect. It is also indicated that the acoustic interaction force between the particles decreases by the relaxation time and increases by the fluid's viscosity. A mathematical formula is proposed for the acoustic interaction force between particles located close to each other in a viscoelastic fluid.