Regime Diagram Research Articles

Self-trapping and switching of solitonic pulses in mismatched dual-core highly nonlinear fibers

We investigate experimentally and theoretically effects of the inter-core propagation mismatch on nonlinear switching in dual-core high-index-contrast soft-glass optical fibers. Incident femtosecond pulses of various energy are fed into a single (“straight”) core, to identify transitions between different dynamical regimes, viz., inter-core oscillations, self-trapping in the cross core, and retaining the pulse in the straight core. The transfer between channels, which has solitonic character, is controlled by the pulse’s energy. A model based on the system of coupled nonlinear Schrödinger equations reveals the effect of the mismatch parameter and pulse duration on the diagram of the various energy dependent dynamical regimes. Optimal values of the mismatch and pulse width, which ensure stable performance of the nonlinear switching, are identified. The theoretical predictions are in agreement with experimental findings.

Experimental Study of an upflow Fluidized Bed: Identification of Fluidization Regimes

The concept of solar receiver using fluidized particles as heat transfer fluid is attractive from the point of view of its performance but also of the material used. In this concept, the receiver is composed of tubes subjected to concentrated solar radiation in which the fluidized particles circulate vertically. Circulation in the tubes, immersed in a “nurse” fluidized bed, is ensured thanks to a controlled pressure difference imposed on the latter and secondary aeration. This ventilation located at the bottom of the absorber tubes makes it possible to control the fluidization regimes. The latter strongly influence the parietal heat transfers and therefore the performance of the receiver. In order to better understand the conditions of appearance of these regimes and to better identify them, a study at room temperature was carried out with a tube 45 mm in internal diameter and 3.63 m in height. The tube is instrumented with several pressure sensors distributed over its height. More than 170 experiments have been performed exploring wide ranges of particle and aeration flow rates, with and without particle circulation. Signal processing methods, classically used in the scientific literature of fluidized beds, are applied. Combined together, these methods have enabled the identification of bubbling, pistoning (of the wall and axisymmetric), turbulent fluidization and rapid fluidization regimes. The pooling of all this information allows the establishment of a diagram of the fluidization regimes and their transition, showing that the local slip velocity is the key parameter governing the structure of the flow.

REGIMES FOR FLOW-BLURRING AND FLOW-FOCUSING ATOMIZATION OF NEWTONIAN AND NON-NEWTONIAN FLUIDS

This paper presents a detailed mapping of flow-blurring (FB) and flow-focusing (FF) atomization as relevant to Newtonian fluids and non-Newtonian fluids. Two Newtonian fluids with different viscosities are tested, along with a non-Newtonian fluid, where the properties are similar to those of human saliva. Images featuring the fragmentation characteristics are presented with regime diagrams describing the transition from flow-focusing to flow-blurring. Flow-blurring refers to a mode of atomization where the fluid is partially aerated with gas bubbles to assist breakup, while flow-focusing has similarities to air-blast atomization (AB). The regime transition map developed for FF/FB atomizers reveals the parameters, which define transitions from the flow-focusing to the flow-blurring regime. Along with the transition identification, the breakup regime map also details the fragment morphology of the atomizing liquid stream as a function of the governing dimensionless groups.

A Regime Diagram for Internal Lee Waves in Coastal Plain Estuaries

Abstract Using an idealized channel representative of a coastal plain estuary, we conducted numerical simulations to investigate the generation of internal lee waves by lateral circulation. It is shown that the lee waves can be generated across all salinity regimes in an estuary. Since the lateral currents are usually subcritical with respect to the lowest mode, mode-2 lee waves are most prevalent but a hydraulic jump may develop during the transition to subcritical flows in the deep channel, producing high energy dissipation and strong mixing. Unlike flows over a sill, stratified water in the deep channel may become stagnant such that a mode-1 depression wave can form higher up in the water column. With the lee wave Froude number above 1 and the intrinsic wave frequency between the inertial and buoyancy frequency, the lee waves generated in coastal plain estuaries are nonlinear waves with the wave amplitude Δh scaling approximately with , where V is the maximum lateral flow velocity and is the buoyancy frequency. The model results are summarized using the estuarine classification diagram based on the freshwater Froude number Frf and the mixing parameter M. The Δh decreases with increasing Frf as stronger stratification suppresses waves, and no internal waves are generated at large Frf. The Δh initially increases with increasing M as the lateral flows become stronger with stronger tidal currents, but decreases or saturates to a certain amplitude as M further increases. This modeling study suggests that lee waves can be generated over a wide range of estuarine conditions.

Effect of Base Fluids on the Initiation of Vortex Shedding for Nanofluid Flow Over a Circular Object

Abstract An inherently steady separated flow of a nanofluid around a two-dimensional circular object can be transformed into an unsteady periodic flow by controlling the nanoparticle concentration. This has been established in the contemporary literature 2022 by Garai et al. (2022, “Triggering Vortex Shedding for the Free Stream Flow of Nanofluids Around Bluff Objects,” ASME J. Fluids Eng., 144(3), p. 034502.) using Cu–H2O and Ag–H2O nanofluids, where the base fluids remain the same (H2O) and the nanoparticles are different (Cu, Ag). However, it may be anticipated that changing the base fluid may cause certain alterations in the flow dynamics. Two different base fluids, e.g., propylene glycol (C3H8O2) and ethylene glycol (C2H6O2) are selected in which copper (Cu) nanoparticles are mixed to produce Cu–C3H8O2 and Cu–C2H6O2 nanofluids. The nanofluids flow over a circular object with Reynolds number in the range 15≤Re≤40. The Cu nanoparticle concentration is gradually increased and it is observed that the vortex shedding can be initiated with a lesser concentration of Cu in case of C3H8O2 based nanofluid compared to C2H6O2 and also H2O based nanofluids. Hence, the critical solid volume fractions (φcr) for Cu–C2H6O2 based nanofluid are more compared to Cu–C3H8O2 and Cu–H2O nanofluids. Further, φcr for all the nanofluids are found a decreasing function of Re in its chosen range. The critical solid fraction is estimated from an extended Stuart–Landau model and the phenomena are demonstrated qualitatively through the streamlines and vorticity contours and quantitatively through the lift signal analysis and phase diagrams. Finally, a regime diagram is constructed to demarcate the steady and unsteady zones of operation.

Detonation development in hydrogen/air mixtures inside a closed chamber: role of a cold wall

Detonation development from a hot spot has been extensively studied, where ignition occurs earlier than that in the surrounding mixtures. It has also been reported that a cool spot can induce detonation for large hydrocarbon fuels with Negative Temperature Coefficient (NTC) behavior, since ignition could happen earlier at lower temperatures. In this work we find that even for hydrogen/air mixtures without NTC behaviors, a cold wall can still initiate and promote detonation. End-wall reflection of the pressure wave and wall heat loss introduce an exothermic center outside the boundary layer, and then autoignitive reaction fronts on both sides may evolve into detonation waves. The right branch can be further strengthened by appropriate temperature gradient near the cold wall, and exhibits different dynamics at various initial conditions. The small excitation time and the large diffusivity of hydrogen provide the possibility for detonation development within the limited space between the autoignition kernel and the cold wall. Moreover, detonation may also develop near the flame front, which may or may not co-exist with detonation waves from the cold wall. Correspondingly, wall heat flux evolution exhibits different responses to detailed dynamic structures. Finally, we propose a regime diagram describing different combustion modes including normal flame, autoignition, and detonation from the wall and/or the reaction front. The boundary of normal flame regime qualitatively agrees with the prediction by the Livengood-Wu Integral method, while the detonation development from both the end wall and the reaction front observes Zel'dovich mechanism. Compared to hydrocarbons, hydrogen is resistant to knock onset but it is more prone to superknock development. The latter mode becomes more destructive in the presence of wall heat loss. This study isolates and identifies the role of wall heat loss on a potential mechanism for superknock development in hydrogen-fueled spark-ignition engines.

How Slab Age and Width Combine to Dictate the Dynamics and Evolution of Subduction Systems: A 3‐D Spherical Study

AbstractMany of the factors expected to control the dynamics and evolution of Earth's subduction zones are under‐explored in an Earth‐like spherical geometry. Here, we simulate multi‐material free‐subduction of a complex rheology slab in a 3‐D spherical shell domain, to investigate the effect of plate age (simulated by covarying plate thickness and density) and width on the evolution of subduction systems. We find that the first‐order predictions of our spherical cases are generally consistent with existing Cartesian studies: (a) as subducting plate age increases, slabs retreat more and subduct at a shallower dip angle, due to increased bending resistance and sinking rates; and (b) wider slabs can develop along‐strike variations in trench curvature due to toroidal flow at slab edges, trending toward a “W”‐shaped trench with increasing slab width. We find, however, that these along‐strike variations are restricted to older, stronger, retreating slabs: Younger slabs that drive minimal trench motion remain relatively straight along the length of the subduction zone. We summarize our results into a regime diagram, which highlights how slab age modulates the effect of slab width, and present examples of the evolutionary history of subduction zones that are consistent with our model predictions.

Ice fabrics in two-dimensional flows: beyond pure and simple shear

Abstract. Ice fabrics – the distribution of crystal orientations in a polycrystal – are key for understanding and predicting ice flow dynamics. Despite their importance, the characteristics and evolution of fabrics produced outside of the deformation regimes of pure and simple shear flow has largely been neglected, yet they are a common occurrence within ice sheets. Here, we use a recently developed numerical model (SpecCAF) to classify all fabrics produced over a continuous spectrum of incompressible two-dimensional deformation regimes and temperatures. The model has been shown to accurately predict ice fabrics produced in experiments, where the ice has been deformed in either uniaxial compression or simple shear. Here we use the model to reveal fabrics produced in regimes intermediate to pure and simple shear, as well as those that are more rotational than simple shear. We find that intermediate deformation regimes between pure and simple shear result in a smooth transition between a fabric characterised by a girdle and a secondary cluster pattern. Highly rotational deformation regimes are revealed to produce a weak girdle fabric. Furthermore, we provide regime diagrams to help constrain deformation conditions of measured ice fabrics. We also obtain predictions for the strain scales over which fabric evolution takes place at any given temperature. The use of our model in large-scale ice flow models and for interpreting fabrics observed in ice cores and seismic anisotropy provides new tools supporting the community in predicting and interpreting ice flow in a changing climate.

Regimes and Transitions in the Basal Melting of Antarctic Ice Shelves

Abstract The Antarctic Ice Sheet is losing mass as a result of increased ocean-driven melting of its fringing ice shelves. Efforts to represent the effects of basal melting in sea level projections are undermined by poor understanding of the turbulent ice shelf–ocean boundary layer (ISOBL), a meters-thick layer of ocean that regulates heat and salt transfer between the ocean and ice. To address this shortcoming, we perform large-eddy simulations of the ISOBL formed by a steady, geostrophic flow beneath horizontal ice. We investigate melting and ISOBL structure and properties over a range of free-stream velocities and ocean temperatures. We find that the melting response to changes in thermal and current forcing is highly nonlinear due to the effects of meltwater on ISOBL turbulence. Three distinct ISOBL regimes emerge depending on the relative strength of current shear and buoyancy forcing: “well-mixed,” “stratified,” or “diffusive-convective.” We present expressions for mixing-layer depth for each regime and show that the transitions between regimes can be predicted with simple nondimensional parameters. We use these results to develop a novel regime diagram for the ISOBL which provides insight into the varied melting responses expected around Antarctica and highlights the need to include stratified and diffusive-convective dynamics in future basal melting parameterizations. We emphasize that melting in the diffusive-convective regime is time dependent and is therefore inherently difficult to parameterize. Significance Statement The purpose of this study is to investigate the processes that control ocean-driven melting of Antarctic ice shelves (100–1000-m-thick floating extensions of the Antarctic ice sheet). Currently, these processes are poorly understood due to the difficulty of accessing the ocean beneath ice shelves. Using an ocean model, we determine the melting response to different ocean conditions, including feedbacks whereby cold, fresh meltwater can enhance or suppress turbulent eddies beneath the ice, depending on the ocean state. Our results point the way to improvements in the representation of ocean-driven melting in ocean/climate models, which will allow more accurate predictions of future climate and sea level.

Impact Dynamics of a Single Droplet on Hydrophobic Cylinders: A Lattice Boltzmann Study.

This study numerically investigates the effects of the Weber number (We) and cylinder-to-droplet radius ratio (R*) on the impact dynamics of a low-viscosity droplet on a hydrophobic cylinder by the lattice Boltzmann method. The intrinsic contact angle of the surface is chosen as θ0 = 122°± 2°, which ensures a representative hydrophobicity. The regime diagram of the impact dynamics in the parameter space of We versus R* is established with categories of split and nonsplit regimes. The droplet would split during impact as α = We/R* exceeds a critical value. In the nonsplit regime, the droplet bounces off the cylinder at most Weber numbers unless the impact velocity is minuscule (We < 2). The contact time of the droplet on the cylinder surface decreases with increasing R* or decreasing We, indicating bouncing is facilitated under such conditions. This can be explained by the suppressed adhesion dissipation between the droplet and surface due to a reduction in the contact area. In the split regime, sufficient kinetic energy inside the impacting droplet determines whether the whole droplet could detach from the surface. With a small cylinder (R* < 0.83) and large We (>25), the adhesion effect is weakened for the side fragments because of the small contact area, and it facilitates the dripping of fragments. For other conditions, the detachment, especially for the tiny droplet on the cylinder top, only occurs if the deformation is prominent at We > 35. Moreover, the spreading dynamics of the impacting droplet are also highlighted in this work.

Characterisation and Design of Direct Numerical Simulations of Turbulent Statistically Planar Flames

This work aims to provide support for the design of reliable DNSs for statistically planar flames. Improved simulation design strategies are developed. Therefore, design criteria for the simulative domain are discussed. The gained mathematical relations for all of the relevant physical quantities were channelled into a deterministic calculation strategy for mesh features. To choose design parameter values within the mathematical formulations, guidelines were formulated. For less controllable variables, namely the viscosity and Prandtl number, a measurement technique was developed. A new determination strategy to determine characteristic points within the flame front was conducted. In order to present and compare cases with different Prandtl numbers, normalisation of the x-axis of the regime diagram was suggested.

Simulation of two successive drops impacting a heated wall by smoothed particle hydrodynamics with adaptivespatial resolution

<p indent="0mm">A numerical method for evaporating multiphase flow was developed by introducing a diffusion equation of species and a phase change model to smoothed particle hydrodynamics with adaptive spatial resolution (SPH-ASR). The method was applied to study the impact problem of two successive drops on a heated wall. The numerical method was validated against experimental results. Different factors were considered in the simulations, including drop diameter, impact velocity, wall temperature and wall inclined angle. The typical impact regimes were obtained, including spread, breakup, contact splash, rebound, and film splash. The numerical results indicated that the outcome of two drops impacting a solid wall mainly depends on the temperature and inclined angle of the wall, Weber number, and Reynolds number. Different phase diagrams of impact regimes were obtained using different parameters. A linear relationship between the critical Weber number of splash and the inclined angle of wall was obtained by data fitting.

Dynamic thermal analysis of startup process for minichannel evaporator

• Start-up regimes of minichannel evaporator are formulated by transfer function. • Evaluation criteria in control theory are proposed to describe start-up behaviors. • Startup performances of minichannel evaporator are quantitatively investigated. • Working fluid with small subcooling degree is beneficial for evaporator start-up. • Evaporator temperature overshoot can be alleviated via increasing heat load. The start-up performance of minichannel evaporator in a mechanically pumped two-phase loop (MPTL) is investigated in terms of the dynamic temperature response. A preliminary start-up regime diagram is identified, where temperature response of start-up process can be recognized as three modes, including the gradual start-up, once-rise overshoot start-up and twice-rise overshoot start-up. Theoretical analysis and model identification are conducted via Laplace-transformation and representative evaluation criterion is proposed to realize the quantitative characterization of specific start-up mode. Time constant and settling time act as the indicators to evaluate temperature response rate, while overshoot is utilized to assess the two-phase flow instability. The results indicate that: for gradual start-up mode, the time to reach quasi-steady state is smaller as heat transfer performance improves via increasing heat load, while temperature response rate is relatively insensitive to flow rate; for once-rise overshoot start-up mode, the two-phase flow instability can be alleviated via increasing the heat load, while the increment of flow rate could intensify the instability; for twice-rise overshoot start-up mode, the temperature overshoot is insensitive to heat load variation. Moreover, preheating the working fluid at evaporator inlet is beneficial to mitigate the instability, indicating that preheater/regenerator can optimize the robustness/stability of start-up.

Internal group combustion of droplet clouds and its transition to external group combustion under two-stage autoignition conditions

The present study is an extension of our prior study on the external group combustion (EGC) of droplet clouds under two-stage autoignition conditions [Zhou and Liu, Combust. Flame 234 (2021) 111689]. Effects of droplet heating and different n-alkane fuel candidates have been further considered. By comparing numerical results from n-heptane and n-dodecane, it was found that the fuel volatility has little effect on the combustion modes of droplet clouds. Among all the computed cases, internal group combustion (IGC) occurs for relatively low value of group ignition number Gig (= 4πn2/3d2, n and d are the droplet number density and diameter, respectively). When Gig further increases, the combustion mode can switch to EGC. IGC modes can be sustained by cool or hot flame. IGC of cool flame exhibits a partial burning structure, while IGC of hot flame is firstly premixed, followed by non-premixed structure. These flame structures were analyzed in details. A regime diagram based on Gig and ambient temperature Ta was developed for all the IGC modes. It was found that for high Ta (1500 K), Gig can be used to predict ICG modes, but for low Ta (900 K) and intermediate Ta (1200 K), additional parameters might be needed for the prediction, especially for the cases when Gig is around 0.03. The inapplicability is due to the strong interaction between droplet behavior (droplet heating and vaporization) and chemical kinetics (low and high temperature reaction) that were not inherent to description of Gig. To clarify the interaction, time scale analysis of these processes was performed for better complementation of the regime diagram characterized by Gig and Ta for various IGC modes.

Karlovitz Numbers and Premixed Turbulent Combustion Regimes for Complex-Chemistry Flames

The structure of premixed turbulent flames and governing physical mechanisms of the influence of turbulence on premixed burning are often discussed by invoking combustion regime diagrams. In the majority of such diagrams, boundaries of three combustion regimes associated with (i) flame preheat zones broadened locally by turbulent eddies, (ii) reaction zones broadened locally by turbulent eddies, and (iii) local extinction are based on a Karlovitz number Ka, with differently defined Ka being used to demarcate different combustion regimes. The present paper aims to overview different definitions of Ka, comparing them, and suggesting the most appropriate choice of Ka for each combustion regime boundary. Moreover, since certain Karlovitz numbers involve a laminar flame thickness, the influence of complex combustion chemistry on the thickness and, hence, on various Ka and relations between them is explored based on results of complex-chemistry simulations of unperturbed (stationary, planar, and one-dimensional) laminar premixed flames, obtained for various fuels, equivalence ratios, pressures, and unburned gas temperatures.

Local effects in vortex-flame interactions: Implications for turbulent premixed flame scaling and observables

A computational investigation was carried out to assess the effects of highly energetic vortices on the local structure of laminar premixed flames. The study involved a lean atmospheric methane-air flame interacting with vortex sizes ranging from five times to half of the laminar flame thickness. The characteristic velocities of the vortices were chosen to correspond to extreme turbulence intensities. Vortices smaller than the flame thickness were found to have a minimal effect on the flame structure due to the high rate of dissipation. Vortices with sizes greater than or equal to the flame thickness were found to induce flame siphoning and/or product-side local flame annihilation and as a result transport considerable amounts of formaldehyde and thermal energy to the unburned side thereby modifying the state of the reactants. The results of the present study for high activation energy reacting flows raise questions regarding the general validity of: (1) conjectured mechanisms of the so-called flame broadening under intense turbulence conditions; and (2) qualitative arguments regarding sub-flame-thickness vortex effects on the preheat zone in the context of the Borghi–Peters regime diagram, as originally postulated by Damköhler.

Role of ozone addition on premixed hydrogen/oxygen flames: Multi-zone structure and multi-regime dynamics

This study investigates the effects of additive ozone on the ignition and propagation of premixed hydrogen/oxygen flames, with emphasis on the steady flame structure and the transient ignition and propagation behaviors due to the ozone chemistry and transport. We first simulate the 1D freely-propagating hydrogen/oxygen flames with and without additive ozone, and demonstrate that the ozone-enhanced flame has a triple reaction layer structure, which consists of an ozone reaction layer, with substantial heat release, situated within the entire preheat zone. This spatially non-monotonic nature of the heat release rate and the associated temperature gradient then implies that the conventional definition of the flame thickness, δ=(Tb-Tu)/(dT/dx)max, is incapable and indeed inappropriate to characterize the ozone-enhanced flame thickness. The multi-zone flame structure then leads to multi-regime flame dynamics, with the structure of a single ozone-sustained branch followed by decoupled and coupled double branches controlled by ozone and oxygen reactions respectively. The critical radius and the transition regime of the ozone branch are captured over a wide range of equivalence ratios, which are induced by the large Lewis number of ozone and the interaction between the ozone and oxygen branches. As such, the regime diagram of the flame propagation speed versus the stretch rate respectively corresponds to three to six regimes in the ozone branch, and zero to five regimes in the oxygen branch under ultra-(fuel)-lean, fuel-lean, stoichiometric and fuel-rich conditions. The modification of the minimum ignition energy in ozone–assisted flames is also noted.

Dynamics of droplet breakup in unilateral Y-junctions with different angles

Dynamic behaviors of droplets in asymmetric unilateral Y-junctions are experimentally studied. Three breakup regimes are categorized, namely no breakup, breakup with gaps and breakup with obstruction, and regime diagrams are constructed by the capillary number and the normalized droplet length. Influences of the bifurcation angle and the viscosity ratio on the two critical conditions between neighboring regimes are revealed. In particular, necking processes in the obstructed breakup regime are discussed and they are divided into three stages according to the evolution of the thinning rate. At the two previous stages driven by the two-phase flow, the necking processes show distinct characteristics under the influences of four different parameters, including capillary number, droplet length, viscosity ratio, and bifurcation angle, and the corresponding reasons are provided in detail. By contrast, the final pinch-off stage is driven by two different mechanisms depending merely on the physical properties of liquid systems. The neck collapsing of the low-viscosity droplet is driven by the potential flow while that of the high-viscosity droplet is driven by the two-fluid Stokes flow. Quantitative relations between the minimum neck width and the remaining time are built in the two situations and are found to coincide with the theoretical predictions, respectively.

Ultra-lean dynamics of a holder-stabilized hydrogen enriched flames in a preheated mesoscale combustor

To provide the theoretical basis to suppress the unstable flames under the coupling effect of flow and heat recirculation, the present work experimentally studies the ultra-lean dynamics of a holder stabilized 40%H2–60%CH4–air premixed flame in a preheated mesoscale combustor. The regime diagram of the flame behaviors at various operating conditions is obtained. It is observed that the blow-off limit first increases slightly and then decreases sharply (the anomalous blow-off limit) with the decreased Re value. Three types of the flame behaviors (i.e., the conventional stable flame, the stable residual flame, and the periodic oscillating residual flame) are found before the flame blow-off. In addition, with the decreased Reynolds number, the operating range for the stable residual flame broadens first and then narrows, but that of the periodic oscillating residual flame decreases monotonically, which are observed for the first time. The results show that, with the decreased Reynolds number, the flame root of the conventional stable flame anchors almost at the same location right behind the holder, while the flame tips obviously shift upstream. With the decreased equivalence ratio, the left and right flame tips in the downstream channel shift toward each other and finally merge into a single flame tip, which results in the formation of the stable residual flame. When the equivalence ratio decreases further, the periodic oscillating residual flame occurs. The flame tip periodically oscillates up and down over time. In the end, the blow-off dynamics of the stable residual flame and periodic oscillating residual flame are revealed.

A numerical study of the coalescence of hollow droplets under solidification

This paper presents the results of numerical simulations of the coalescence and solidification of two hollow droplets. A base droplet (i.e., a pre-solidified droplet) stays on a supercool surface that causes its shell liquid to solidify. An incoming droplet then flows toward and coalesces with the base droplet. After coalescence of the droplets, the two hollow cores can coalesce depending on the momentum of the incoming hollow core and the solidification rate. A high solidification rate corresponding to a high Stefan number St prevents the hollow cores from coalescing and thus induces a discrete hollow-core solidified product, whereas a low St number results in a coalesced hollow-core (CH) droplet. However, the coalescence of two droplets and/or their hollow cores does not affect the apex at the top of the final solidified droplet, which is created by volume expansion upon phase change. Some other parameters including the Peclet number Pe, the Weber number We, the size Ris of the incoming inner core, the position Hs of the incoming droplet and the number of cores Ni of the incoming droplet also affect the coalescence and phase transition of the droplets. It is found that transition from a CH region to a discrete hollow-core region occurs for lower Pe, Ris, or Ni. In contrast, decreasing the value of We or Hs enhances the CH region. Moreover, we provide regime diagrams based on the supercooling degree, the Peclet number, and the size of the inner core of the incoming droplet.