arXiv subjects

Ganesh Subramanian

Publications and source records attributed to Ganesh Subramanian.

At least 19 recordsLinked to original sources

arXiv2026

Convective scalar transport from spherical drops in complex shearing flows

We calculate the scalar transport rate, as characterized by the Nusselt number\,($Nu$), from a neutrally buoyant spherical drop in an ambient linear flow, in the absence of inertia and in the strong convection limit. This corresponds to the regime $Re \ll 1, Pe \gg 1$, where $Re$ and $Pe$ are the Reynolds and P\'eclet numbers, and denote the ratios of the diffusive and convective time scales associated with momentum and scalar transport. The focus is on the exterior problem, with the drop-phase transport resistance assumed negligible, and the scalar field being a constant on the drop surface. While $Nu \propto Pe^{\frac{1}{2}}$ for $Pe \gg 1$, owing to the transport occurring across a thin $O(a Pe^{-\frac{1}{2}})$ boundary layer\,($a$ being the drop radius), the proportionality factor in this relation depends sensitively on ambient flow geometry via the surface-streamline topology. Unlike a rigid sphere, a variety of surface-streamline topologies can drive transport across the boundary layer at widely differing rates. In contrast to earlier studies which almost exclusively focus on axisymmetric ambient flows, we calculate $Nu$ for a pair of non-axisymmetric linear flow families: (i) 3D extensional flows with aligned vorticity and (ii) Axisymmetric extensional flows with inclined vorticity, using a non-orthogonal surface-streamline aligned coordinate system. Taken together, the families span the entire gamut of surface-streamline topologies in the space of incompressible linear flows. Independent numerical simulations of the interior problem reveal the emergence of an $O(aPe^{-\frac{1}{2}})$ boundary layer beneath the drop surface, driven by chaotic streamlines, pointing to the possibility of $Nu \propto Pe^{\frac{1}{2}}$ for the conjugate problem, for sufficiently large $Pe$.

physics.flu-dyn↗

arXiv2025

Transition in elastic Dean flow: the centre-mode versus hoop-stress pathways

We analyse the stability of viscoelastic Dean flow (flow of an elastic fluid through a curved two-dimensional channel, driven by an azimuthal pressure gradient) in the absence of fluid inertia. This configuration is well known to exhibit a hoop-stress-driven `purely elastic' instability (referred to henceforth as the hoop-stress mode -- `HSM') on account of the base-flow streamline curvature. The objective of this study is to demonstrate the existence and importance of a distinct elastic instability in this flow configuration, which is not driven by hoop-stresses, but instead is a continuation of a novel `centre-mode' (CM) instability recently identified in rectilinear shear flows. We use both the Oldroyd-B and FENE-P models to map out parameter regimes in the $W\!i$--$\epsilon$--$\beta$ space where the aforementioned instabilities are present. Here, $W\!i$ is a suitably defined Weissenberg number that characterizes fluid elasticity, $\beta$ is the ratio of solvent to total solution viscosity, and $\epsilon$ is the ratio of the gap (channel) width to the radius of curvature. For FENE-P model, decreasing the finite extensibility parameter $L$ has opposing effects on the HSM and CM instabilities -- stabilising the former, but destabilising the latter. In the dilute solution regime ($\beta > 0.95$), and for realistic values of $L \sim O(100)$, corresponding to polymer molecular weights of $O(10^{5-6})$g/mol, the CM remains the most unstable mode for $\epsilon \leq 0.25$, rendering it potentially relevant to the onset of elastic turbulence in the flow of such polymer solutions through curved channels.

physics.flu-dyn↗

arXiv2025

Nature of continuous spectra in wall-bounded shearing flows of FENE-P fluids

Owing to the spatially local nature of the constitutive equations typically used to model polymeric stresses, the differential operators governing the linearized dynamics of bounded viscoelastic shearing flows have singular points. As a result, the eigenspectra of such shearing flows contain, in addition to discrete eigenvalues, continuous spectra (CS) comprising singular eigenfunctions. A clear understanding of the theoretical CS loci is crucial in discriminating physically genuine (discrete) eigenvalues from the poorly approximated numerical CS. For rectilinear shear flows of Oldroyd-B fluids, the CS are a pair of line segments, with lengths equal to the base-state range of velocities. In this study, we provide the first comprehensive account of the nature of the CS for both rectilinear and curvilinear shearing flows of the FENE-P fluid. In stark contrast to the CS for the Oldroyd-B fluid mentioned above, we show analytically that there are up to six distinct continuous spectra for shearing flows of FENE-P fluids. When the finite extensibility parameter $L > 50$, as appropriate for large molecular weight polymers used in experiments, three of the CS are nearly identical, and independent of the solvent-to-solution viscosity ratio ($\beta$). The other three CS are $\beta$-dependent, with one of them being the analogue of the solvent (viscous) continuous spectrum in the Oldroyd-B fluid. The remaining two $\beta$-dependent CS are novel features of the FENE-P spectrum, and can have phase speeds outside the base range of velocities, including negative ones. The complexity of the CS predicted here for shearing flows of FENE-P fluids is expected to carry over to other nonlinear viscoelastic models that exhibit a shear-thinning rheology.

physics.flu-dyn↗

arXiv2025

Inertial migration of slender prolate and thin oblate spheroids in plane Poiseuille flow

We theoretically examine the inertial migration of a neutrally buoyant spheroid of aspect ratio $\kappa$ in wall-bounded plane Poiseuille flow at small particle Reynolds number ($Re_p$) and small confinement ratio ($\lambda$), with channel Reynolds number $Re_c = Re_p/\lambda^2$ arbitrary. For $\lambda \ll 1$, inertia rapidly drives the spheroid to the tumbling orbit ($C = \infty$), with migration governed by the time-averaged lift over orientations sampled in this orbit. Spheroids with $\kappa = O(1)$ follow Jeffery rotation closely, while deviations for slender rods and thin disks yield equilibrium positions distinct from the classical Segre-Silberberg result. Above a threshold $Re_c$, both rods and disks can undergo rotation arrest near walls, with these arrested regions expanding toward the centerline as $Re_c$ increases. Unlike spheres, the resulting equilibrium positions shift inward with increasing $Re_c$; for disks, these positions themselves become arrested beyond a threshold $Re_c$. The $\kappa$-dependence of equilibrium locations suggests passive shape-sorting strategies in microfluidic devices.

physics.flu-dyn↗

arXiv2025

Orientation dynamics of a spheroid in the simple shear flow of a weakly elastic fluid

We investigate the orientation dynamics of a neutrally buoyant spheroid, of an arbitrary aspect ratio ($κ$), freely rotating in a weakly viscoelastic fluid undergoing simple shear flow. Weak elasticity is characterized by a small but finite Deborah number ($De$), and the suspending fluid rheology is therefore modeled as a second-order fluid, with the constitutive equation involving a material parameter $ε$ related to the ratio of the first and second normal stress differences; polymer solutions correspond to $ε\in[-0.7,-0.5]$. Employing a reciprocal theorem formulation, along with expressions for the relevant disturbance fields in terms of vector spheroidal harmonics, we obtain the spheroid angular velocity to $O(De)$. In the Newtonian limit, a spheroid rotates along Jeffery orbits parametrized by an orbit constant $C$, although this closed-trajectory topology is structurally unstable, being susceptible to weak perturbations. For $De$ well below a threshold, $De_c(κ)$, weak viscoelasticity transforms the closed-trajectory topology into a tightly spiralling one. A multiple-scales analysis is used to interpret the resulting orientation dynamics in terms of an $O(De)$ orbital drift. The drift in orbit constant over a Jeffery period $ΔC$, when plotted as a function of $C$, identifies four different orientation dynamics regimes on the $κ-ε$ plane. For $ε$ in the polymeric range, prolate spheroids always drift towards the spinning mode. Oblate spheroids drift towards the tumbling mode for $κ> κ_c(ε)$, but towards an intermediate kayaking mode for $κ< κ_c(ε)$. The rotation of spheroids of extreme aspect ratios, either slender prolate spheroids ($κ\gg 1$) or thin oblate ones ($κ\ll 1$), about the vorticity axis, is arrested for $De \geq De_c(κ)$

physics.flu-dyn↗

arXiv2025

The orientation dynamics of a massive ellipsoid in simple shear flow

The orientation dynamics of a massive rigid ellipsoid in simple shear flow of a Newtonian fluid is investigated in detail. The term `massive' refers to dominant particle inertia, as characterized by $St \gg 1$, $St = \dotγl^2ρ_p/νρ_f$ being the Stokes number; here, $\dotγ$ is the shear rate, $ν$ is the kinematic viscosity, $l$ is a characteristic ellipsoidal dimension (taken to be the longest semi axis), and $ρ_p$ and $ρ_f$ are the particle and fluid densities, respectively. Fluid inertial effects are neglected, so the particle Reynolds number ($Re$) is zero. The equations of motion of the ellipsoid in this limit reduce to those governing an Euler top, supplemented by a weak viscous torque. The dynamics consists of a fast conservative motion on time scales of $O(\dotγ^{-1})$ that, for an ellipsoid, involves a combination of spin, precession and nutation, and a slower component driven by the viscous torque; the latter modulates the angular momentum and rotational kinetic energy on asymptotically longer time scales of $O(St{\dotγ}^{-1})$. The separation of time scales for large $St$ allows for use of the method of averaging for a triaxial ellipsoid, to derive an autonomous system of ODE's that govern motion on a four-dimensional slow manifold consisting of the three angular momenta and the rotational kinetic energy. There are three fixed points on the slow manifold, with rotation about the shortest axis being stable. The fixed point corresponding to rotation about the longest axis is a saddle point, while intermediate-axis-aligned rotation corresponds to a singular fixed point. For spheroids, the singular fixed point merges with one of the other two, leading to only two fixed points, one a stable node and the other a saddle; the former corresponds to rotation about the shorter axis.

physics.flu-dyn↗

arXiv2024

Instabilities in strongly shear-thinning viscoelastic flows through channels and tubes

The linear stability of a shear-thinning, viscoelastic fluid undergoing any of the canonical rectilinear shear flows, viz., plane Couette flow and pressure-driven flow through a channel or a tube is analyzed in the creeping-flow limit using the White--Metzner model with a power-law variation of the viscosity with shear rate. While two-dimensional disturbances are considered for plane Couette and channel flows, axisymmetric disturbances are considered for pressure-driven flow in a tube. For all these flows, when the shear-thinning exponent is less than $0.3$, there exists an identical instability at wavelengths much smaller than the relevant geometric length scale (gap between the plates or tube radius). There is also a finite-wavelength instability in these configurations governed by the details of the geometry and boundary conditions at the centerline of the channel or tube. The most unstable mode could be either of the short-wave or finite-wavelength instabilities depending on model parameters. For pressure-driven channel flow, it is possible to have sinuous or varicose unstable modes depending on the symmetry of the normal velocity eigenfunction about the channel centerline. This difference in symmetry is relevant only for the finite wavelength instability, in which case sinuous modes turn out to be more unstable, in accordance with experimental observations. In all the three configurations, the short wavelength unstable modes are localized near the walls, and are insensitive to symmetry conditions at the centerline. It is argued that this instability should be a generic feature in any wall-bounded shear flow of strongly shear-thinning viscoelastic fluids. Our predictions for the finite-wavelength instability in pressure-driven channel and pipe flows are in good agreement with experimental observations for the flow of concentrated polymer solutions in these geometries.

physics.flu-dyn↗

arXiv2024

The flow field due to a sphere moving in a viscous, density stratified fluid

We study the flow field induced by a sphere translating in a viscous density-stratified ambient, specifically, in the limit of small Reynolds $(Re = ρU a/μ\ll 1)$, and viscous Richardson numbers $(Ri_v = γa^3 g/μU\ll 1)$, and large Peclet number $(Pe = Ua/D\gg 1)$. Here, $a$ is the sphere radius, $U$ its translational velocity, $ρ$ an appropriate reference density within the Boussinesq framework, $μ$ the ambient viscosity, $γ$ the absolute value of the background density gradient, and $D$ the diffusivity of the stratifying agent. For the scenario where buoyancy forces first become comparable to viscous forces at large distances, corresponding to the Stokes-stratification regime defined by $Re \ll Ri_v^{1/3} \ll 1$ for $Pe \gg 1$, important flow features such as a vertical reverse jet and a horizontal wake, on scales larger than the primary screening length of $\mathcal{O}(aRi_v^{-1/3})$, have been identified by Varanasi and Subramanian (2022). Here, we show that the reverse jet is only the central portion of a columnar structure with multiple annular cells. In the absence of diffusion this columnar structure extends to downstream infinity with the number of annular cells diverging in this limit. We provide expressions for the boundary of the structure, and the number of cells within, as a function of the downstream distance. For small but finite diffusion, two additional length scales emerge - a secondary screening length of $O(aRi_v^{-1/2}Pe^{1/2})$, where diffusion starts to smear out density variations across cells, leading to exponentially decaying flow field; and a tertiary screening length, of $O(aRi_v^{-1/2}Pe^{1/2}\ln(Ri_v^{-1}Pe^3))$, beyond which the columnar structure ceases to exist and the downstream disturbance field reverts from an exponential to eventual algebraic decay, analogous to that prevalent at large distances upstream.

physics.flu-dyn↗

arXiv2024

A viscous drop in a planar linear flow -- the role of deformation on streamline topology

Planar linear flows are a one-parameter family, with the parameter $\hatα\in [-1,1]$ being a measure of the relative magnitudes of extension and vorticity; $\hatα = -1$, $0$ and $1$ correspond to solid-body rotation, simple shear flow and planar extension, respectively. For a neutrally buoyant spherical drop in a hyperbolic planar linear flow with $\hatα\in(0,1]$, the near-field streamlines are closed for $0 \leq \hatα < 1$ and for $λ> λ_c = 2 \hatα / (1 - \hatα)$, $λ$ being the drop-to-medium viscosity ratio; all streamlines are closed for an ambient elliptic linear flow with $\hatα\in[-1,0)$. We use both analytical and numerical tools to show that drop deformation, as characterized by a non-zero capillary number ($Ca$), destroys the aforementioned closed-streamline topology. While inertia has previously been shown to transform closed Stokesian streamlines into open spiraling ones that run from upstream to downstream infinity, the streamline topology around a deformed drop, for small but finite $Ca$, is more complicated. Only a subset of the original closed streamlines transforms to open spiraling ones, while the remaining ones densely wind around a configuration of nested invariant tori. Our results contradict previous efforts pointing to the persistence of the closed streamline topology exterior to a deformed drop and have important implications for transport and mixing.

physics.flu-dyn↗

arXiv2023

Disposable face masks: a direct source for inhalation of microplastics

Surgical masks have played a crucial role in healthcare facilities to protect against respiratory and infectious diseases, particularly during the COVID-19 pandemic. However, the synthetic fibers, mainly made of polypropylene, used in their production may adversely affect the environment and human health. Recent studies have confirmed the presence of microplastics and fibers in human lungs and have related these synthetic particles with the occurrence of pulmonary ground glass nodules. Using a piston system to simulate human breathing, this study investigates the role of surgical masks as a direct source of inhalation of microplastics. Results reveal the release of particles of sizes ranging from nanometers (300 nm) to millimeters (~2 mm) during normal breathing conditions, raising concerns about the potential health risks. Notably, large visible particles (> 1 mm) were observed to be ejected from masks with limited wear after only a few breathing cycles. Given the widespread use of masks by healthcare workers and the potential future need for mask usage by the general population during seasonal infectious diseases or new pandemics, developing face masks using safe materials for both users and the environment is imperative.

physics.med-ph↗

arXiv2023

Inertial migration of a neutrally buoyant spheroid in plane Poiseuille flow

We study the cross-stream inertial migration of a torque-free neutrally buoyant spheroid, of an arbitrary aspect ratio $κ$, in wall-bounded plane Poiseuille flow for small particle Reynolds numbers\,($Re_p\ll1$) and confinement ratios\,($λ\ll1$), with the channel Reynolds number, $Re_c = Re_p/λ^2$, assumed to be arbitrary; here, $λ=L/H$ where $L$ is the semi-major axis of the spheroid and $H$ denotes the separation between the channel walls. In the Stokes limit\,($Re_p =0)$ and for $λ\ll 1$, a spheroid rotates along any of an infinite number of Jeffery orbits parameterized by an orbit constant $C$, while translating with a time dependent speed along a given ambient streamline. Weak inertial effects stabilize either the spinning\,($C=0$) or the tumbling orbit\,($C=\infty$), or both, depending on $κ$. The separation of the Jeffery-rotation and orbital drift time scales, from that associated with cross-stream migration, implies that the latter occurs due to a Jeffery-averaged lift velocity. Although the magnitude of this averaged lift velocity depends on $κ$ and $C$, the shape of the lift profiles are identical to those for a sphere, regardless of $Re_c$. In particular, the equilibrium positions for a spheroid remain identical to the classical Segre-Silberberg ones for a sphere, starting off at a distance of about $0.6(H/2)$ from the channel centerline for small $Re_c$, and migrating wallward with increasing $Re_c$. For spheroids with $κ\sim O(1)$, the Jeffery-averaged analysis is valid for $Re_p\ll1$; for extreme aspect ratio spheroids, the regime of validity becomes more restrictive being given by $Re_p\,κ/\ln κ\ll 1$ and $Re_p/κ^2 \ll 1$ for $κ\rightarrow \infty$\,(slender fibers) and $κ\rightarrow 0$\,(flat disks), respectively.

physics.flu-dyn↗

arXiv2023

Scalar transport from deformed drops: the singular role of streamline topology

We examine scalar transport from a neutrally buoyant drop, in an ambient planar extensional flow, in the limit of a dominant drop phase resistance. For this interior problem, we consider the effect of drop-deformation-induced change in streamline topology on the transport rate (the Nusselt number $Nu$). The importance of drop deformation is characterized by the Capillary number ($Ca$). For a spherical drop ($Ca = 0$), closed streamlines lead to the ratio $Nu/Nu_0$ increasing with the Peclet number($Pe$), from unity to a diffusion-limited plateau value ($\approx 4.1$); $Nu_0$ here denotes the purely diffusive rate of transport. For any finite $Ca$, the flow field consists of spiralling streamlines that densely wind around nested tori foliating the deformed drop interior. $Nu$ now increases beyond the aforementioned primary plateau, saturating in a secondary plateau that approaches $23.3$ for $Ca \rightarrow 0$, $Pe Ca \rightarrow \infty$, and appears independent of the drop-to-medium viscosity ratio. $Nu/Nu_0$ exhibits an analogous variation for other planar linear flows, although chaotically wandering streamlines in these cases are expected to lead to a tertiary enhancement regime.

physics.flu-dyn↗

arXiv2023

Inertial migration in pressure-driven channel flow: beyond the Segre-Silberberg pinch

We examine theoretically the inertial migration of a neutrally buoyant rigid sphere in pressure-driven channel flow, accounting for its finite size relative to the channel width (the confinement ratio). For sufficiently large channel Reynolds numbers\,($Re_c$), a small but finite confinement ratio qualitatively alters the inertial lift velocity profiles obtained using a point-particle formulation. Finite size effects are shown to lead to new equilibria, in addition to the well known Segre-Silberberg pinch locations. Consequently, a sphere can migrate to either the near-wall Segre-Silberberg equilibria, or the new stable equilibria located closer to the channel centerline, depending on $Re_c$ and its initial position. Our findings are in accord with recent experiments and simulations, and have implications for passive sorting of particles based on size, shape and other physical characteristics, in microfluidic applications.

physics.flu-dyn↗

arXiv2022

Anomalous dispersion of microswimmer populations

We examine the longitudinal dispersion of spheroidal microswimmers in pressure-driven channel flow. When time scales corresponding to swimmer orientation relaxation, and diffusion in the gradient and flow directions, are well separated, a multiple scales analysis leads to the shear-enhanced diffusivity governing the long-time spread of the swimmer population along the flow\,(longitudinal) direction. For large $Pe_r$, $Pe_r$ being the rotary Peclet number, this diffusivity scales as $O(Pe_r^4D_t)$ for $1 \leq κ\lesssim 2$, and as $O(Pe_r^{\frac{10}{3}}D_t)$ for $κ= \infty$, $D_t$ being the (bare)\,swimmer translational diffusivity and $κ$ the swimmer aspect ratio. For $2 \lesssim κ< \infty$, swimmers collapse onto the centerline with increasing $Pe_r$, leading to an anomalously reduced diffusivity of $O(Pe_r^{5+C(κ)}D_t)$. Here, $C(κ)\!<\!-1$ characterizes the algebraic decay of swimmer concentration outside an $O(Pe_r^{-1})$ central core, with the anomalous exponent governed by large velocity variations sampled by the few swimmers outside this core. $C(κ)$ dips below $-5$ for $κ\gtrsim 10$, leading to a flow-independent bound of $O(κ^{10}D_t)$ for the dispersion of sufficiently slender swimmers.

physics.flu-dyn↗

arXiv2022

Inertial migration of a sphere in plane Couette flow

We study the inertial migration of a torque-free neutrally buoyant sphere in wall-bounded plane Couette flow over a wide range of channel Reynolds numbers, $Re_c$, in the limit of small particle Reynolds number\,($Re_p\ll1$) and confinement ratio\,($λ\ll1$). Here, $Re_c = V_\text{wall}H/ν$ where $H$ denotes the separation between the channel walls, $V_\text{wall}$ denotes the speed of the moving wall, and $ν$ is the kinematic viscosity of the Newtonian suspending fluid; $λ= a/H$, $a$ being the sphere radius, with $Re_p=λ^2 Re_c$. The channel centerline is found to be the only (stable)\,equilibrium below a critical $Re_c\,(\approx 148)$, consistent with the predictions of earlier small-$Re_c$ analyses. A supercritical pitchfork bifurcation at the critical $Re_c$ creates a pair of stable off-center equilibria, symmetrically located with respect to the centerline, with the original centerline equilibrium simultaneously becoming unstable. The new equilibria migrate wallward with increasing $Re_c$. In contrast to the inference based on recent computations, the aforementioned bifurcation occurs for arbitrarily small $Re_p$ provided $λ$ is sufficiently small. An analogous bifurcation occurs in the two-dimensional scenario, that is, for a circular cylinder suspended freely in plane Couette flow, with the critical $Re_c$ being approximately $110$.

physics.flu-dyn↗

arXiv2022

The geometry of planar linear flows

We identify incompressible planar linear flows that are generalizations of the well known one-parameter family characterized by the ratio of in-plane extension to (out-of-plane) vorticity. The latter `canonical' family is classified into elliptic and hyperbolic linear flows with closed and open streamlines, respectively, corresponding to the extension-to-vorticity ratio being less or greater than unity; unity being the marginal case of simple shear flow. The novel flows possess an out-of-plane extension, but the streamlines may nevertheless be closed or open, allowing for an organization, in a three-dimensional parameter space, into regions of `eccentric' elliptic and hyperbolic flows, separated by a surface of degenerate linear flows with parabolic streamlines that are generalizations of simple shear. We discuss implications for various fluid mechanical scenarios.

physics.flu-dyn↗

arXiv2022

Understanding viscoelastic flow instabilities: Oldroyd-B and beyond

The Oldroyd-B model has been used extensively to predict a host of instabilities in shearing flows of viscoelastic fluids, often realized experimentally using polymer solutions. The present review, written on the occasion of the birth centenary of James Oldroyd, provides an overview of instabilities found across major classes of shearing flows. These comprise (i) the canonical rectilinear shearing flows including plane Couette, plane and pipe Poiseuille flows; (ii) viscometric shearing flows with curved streamlines such as those in the Taylor-Couette, cone-and-plate and parallel-plate geometries; (iii) non-viscometric shearing flows with an underlying extensional flow topology such as the flow in a cross-slot device; and (iv) multilayer shearing flows. While the underlying focus in all these cases is on results obtained using the Oldroyd-B model, we also discuss their relation to the actual instability, and as to how the shortcomings of the Oldroyd-B model may be overcome by the use of more realistic constitutive models. All the three commonly used tools of stability analysis, viz., modal linear stability, nonmodal stability, and weakly nonlinear stability analyses are discussed, with supporting evidence from experiments and numerical simulations as appropriate. Despite only accounting for a shear-rate-independent viscosity and first normal stress coefficient, the Oldroyd-B model is able to qualitatively predict the majority of instabilities in the aforementioned shearing flows. The review also highlights, where appropriate, open questions in the area of viscoelastic stability.

physics.flu-dyn↗

arXiv2022

Two-fluid kinetic theory for dilute polymer solutions

We provide a Boltzmann-type kinetic description for dilute polymer solutions based on two-fluid theory. This Boltzmann-type description uses a quasi-equilibrium based relaxation mechanism to model collisions between a polymer dumbbell and a solvent molecule. The model reproduces the desired macroscopic equations for the polymer-solvent mixture. The proposed kinetic scheme leads to a numerical algorithm which is along the lines of the lattice Boltzmann method. Finally, the algorithm is applied to describe the evolution of a perturbed Kolmogorov flow profile, whereby we recover the major elastic effect exhibited by a polymer solution, specifically, the suppression of the original inertial instability.

physics.comp-ph↗