Buoyancy Effects Research Articles

Stability analysis of stratified radiative non-Newtonian Casson nanofluid flow past on stretching/shrinking sheet using two-phase model

An incompressible steady-state 2D (two-dimensional) stratified boundary-driven Casson nanofluid flowing over the stretched/shrinked surface under buoyancy, magnetic and radiative effects is considered. The two-phase Buongiorno model is adopted to express the behavior of nanomaterial with the stratified boundary conditions. A system of nonlinear ODEs (ordinary differential equations) is extracted from the modeled PDEs (partial differential equations) by using the similarity transformations. The shooting scheme is adapted to execute the obtained equations numerically. The achieved results indicate the duality in the solutions at various ranges of the specified constraints like as suction, shrinking or stretching. The stability analysis is done to check the feasibility of solutions by BVP4c in Matlab. It is achieved that an increment in suction constraint enhanced the skin friction for shrinking case. The temperature curves are decreased with an improvement in Casson, suction, buoyancy and stratification parameters. The nanoparticles concentration reduced against the higher Casson, Brownian motion, suction, thermal and solutal stratification parameters. On other hand, an increment in the thermophoresis increases nanoparticles concentration profile.

The investigation of a likely scenario for natural tornado genesis and evolution from an initial instability profile

A likely mechanism for the little-understood tornado genesis is proposed and its numerical implementation is presented. The Burgers-Rott vortex with its axis in the vertical direction is introduced as an instability mechanism, and the flow field then evolves under the influence of the atmospheric pressure, temperature and density variations with altitude. Buoyancy effects are implemented using the Boussinesq model. Results are presented and discussed for a set of conditions including mesh type and size, different turbulence models, and a few different boundary conditions. Post-processed results of the transient simulations including animations contain a wealth of information to help analyze tornado behavior. Velocity contours, pressure contours, vorticity contours, streamlines, and iso-surfaces show the evolution of a complex flow field possessing many characteristics of a tornado. At longer times from the start, the flow field becomes more asymmetric with the vortex core becoming more twisted, and the eye of the vortex drifting away from the axis of the computational domain. The single initial vortex then transitions into multiple vortices of varying size and orientation. These high Reynolds number (ReΓ ∼109) simulation results show flow fields that resemble highly unsteady, turbulent flows with large regions of flow separation, and large eddy size range.

Ion-selective surface electroconvection in conjunction with buoyancy and polymer additive effects

In advanced electrochemical systems, salinity gradients are widespread and profoundly affect the energy distribution and stabilities of the system. In our research, we thoroughly investigated the ion-selective surface electroconvection flow coupling with buoyancy effects and polymer additives. The variation in mass transfer properties and energy budgets are also investigated in detail. Our results show that polymer additives act as a destabilising factor in an unstable configuration when Rayleigh number Ra ≤ 1000. When Ra > 1000, polymer additives play a stabilizing role. For ion transport, viscoelasticity decreases the overlimiting current by up to 41% for no buoyancy effects. However, the overlimiting current drops by only 27% at large Ra number. Finally, details of the energy budgets reveal a marked salinity and elasticity dependency. The polymer additives can act as either kinetic energy (KE) sinks or KE sources. For small Weissenberg number Wi, polymer as KE sinks leading to ion transport reduction. For large Wi, the role of polymer changes to EK sources. The nonlinear ion transport can be attributed to role change of polymer in energy analysis. These mechanisms provide greater insight into the role of polymer in prevent premature cell failure and stabilizing electrodeposition.

Melting of N-eicosane-based composite phase change materials for thermal energy storage application: A computational analysis in a square cavity

The present numerical study examines the thermal performance of composite n-eicosane phase change material (CPCM) with the addition of different nanoparticles such as Al2O3, Cu, Cuo, and GnP, identifying them as CPCM 1, CPCM 2, CPCM 3, and CPCM 4. This study focuses on the melting behavior of CPCMs with concentration ranges of 2, 5, 8, and 10 wt% in a square encapsulated (SE) geometry aimed at designing an energy-efficient CPCM-based thermal energy storage (TES) system for solar photovoltaic (SPV) applications. Mass fraction contours showed that heat flux at higher concentrations (8 and 10 wt%) contributed to a strong solid-liquid interface, which makes the melt front too wide at all CPCMs. Altogether, the addition of GnP in CPCM (CPCM 4) caused enhancement in thermal conductivity and buoyancy effect, leading to earlier completion of the melting than other CPCMs, irrespective of the concentrations. In addition, the 20–30 % reduction in total time with CPCM 4 over the other three CPCMs at high concentrations of 10 wt% With the influence of nanoparticles, the energy storage capacity (ESC) of CPCMs increased by about 10 %, with concentrations ranging from 2 to 10 wt%. In addition, the variation in total energy release rate between CPCM 2 and CPCM 3 was found to be less significant. However, the ESC of CPCM 4 is 8.5 %, 11 %, and 13 % higher than that of CPCM 1, CPCM 2, and CPCM 3, respectively. With the influence of the inherent thermal properties of GnP, the better thermal performance achieved by CPCM 4 confirms its suitability for SPV system designs. Study provides insights into the design of energy-efficient CPCM-based TES systems for SPV applications.

Magnetic dipole effects on unsteady flow of Casson-Williamson nanofluid propelled by stretching slippery curved melting sheet with buoyancy force

In particular, the Cattaneo-Christov heat flux model and buoyancy effect have been taken into account in the numerical simulation of time-based unsteady flow of Casson-Williamson nanofluid carried over a magnetic dipole enabled curved stretching sheet with thermal radiation, Joule heating, an exponential heat source, homo-heterogenic reactions, slip, and melting heat peripheral conditions. The specified flow's partial differential equations are converted to straightforward ordinary differential equations using similarity transformations. The Runge–Kutta–Fehlberg 4-5th order tool has been used to generate solution graphs for the problem under consideration. Other parameters are simultaneously set to their default settings while displaying the solution graphs for all flow defining profiles with the specific parameters. Each produced graph has been the subject of an extensive debate. Here, the analysis shows that the thermal buoyancy component boosts the velocity regime. The investigation also revealed that the melting parameter and radiation parameter had counterintuitive effects on the thermal profile. The velocity distribution of nanofluid flow is also slowed down by the ferrohydrodynamic interaction parameter. The surface drag has decreased as the unsteadiness parameter has increased, while the rate of heat transfer has increased. To further demonstrate the flow and heat distribution, graphical representations of streamlines and isotherms have been offered.

Numerical solution to flow of Casson fluid via stretched permeable wedge with chemical reaction and mass transfer effects

The purpose of this research is to discuss a two-dimensional (2D), laminar, continuous flow of Casson liquid through a stretched porous wedge in the presence of chemical reaction and buoyancy effects over wedge. This research is aimed at analyzing chemically reacting flow of Casson model over a heated porous wedge in order to understand the features of dynamic wedge. The governing equations and involved parameters are nondimensionalized using transformations. Bvp4c, a numerical tool in Matlab is employed to assess the solution. Significant findings of the major dimensionless parameters on state profiles of velocity, temperature and concentration are drawn graphically. The principal results indicate the impacts of Casson parameter, Eckert and Prandtl number, R stretching parameter, [Formula: see text] chemical parameter, Sc Schmidt number, C mass transfer parameter, m wedge angle parameter on concentration, velocity and temperature field. The Sherwood, Nusselt number and skin friction numerical values are presented in tabular form. Major findings show that drag force at wedge declines for greater [Formula: see text]. Nusselt number shrinks for larger behavior for [Formula: see text]. Sherwood number upsurges for greater performance for chemical reaction parameter [Formula: see text]. Moreover, [Formula: see text] upsurges the temperature slowly but the impacts of [Formula: see text] on concentration show a decreasing behavior.

Numerical simulation of buoyancy–driven flow in a human stomach geometry: Comparison of SPH and FVM models

The primary functions of the stomach, including mixing, digestion, and emptying, are affected by the spatial distribution of content properties, and how this distribution changes in response to gravity and wall contraction forces. One aspect that is not well studied is the buoyancy effects that result from content with heterogenous density. A buoyancy–driven flow in a non–deforming stomach is simulated using the Smoothed Particle Hydrodynamics (SPH) and Finite Volume Method (FVM). An aqueous liquid layer is initially placed above a fatty layer of the same volume. The buoyancy effect driven by gravity and strongly influenced by the stomach shape, causes the fat to rise to the top layer and the aqueous liquid to sink to the bottom. Rayleigh–Taylor Instability (RTI) is well–captured in the SPH model in the initial interface flow development. Some detailed flow behaviours are slightly different between the two models once the bulk turnover flow is established, but both models show that the separation process happens rapidly (within 6 s) in the curved geometry of the stomach. The final phase separation is more complete in the FVM compared with the SPH. Sensitivity analysis is conducted in both models to examine the solution accuracy. This work suggests that buoyancy driven flow effects, which have not been investigated previously, occur on a much shorter timescale (6 s) than peristaltic (20 – 60 s) and digestion timescales (hours). This result may help basic understanding of digestive processes and be used to guide food and drug design.

Effect of Buoyancy, Compressive Strength, and Shear Strength of Polyurethane-Clay Composite (PU-CC) Doped with Polyurethane Filler Waste in Soft Clay Application

The application of polyurethane waste as a filler is one of the most cost-effective strategies for enhancing the geotechnical properties in soils. The PU waste from manufacturing economies was prepared with alkaline solutions by submerging into a 0.05 M sodium hydroxide (NaOH) before sieving to 300m sizes. The PU waste as filler was prepared using two heat exposure from microwaves and drying ovens at 60°C and left for 3 hours. Then, the treated and untreated Polyurethane-Clay Composite (PU-CC) was prepared at the different ratios of PU waste filler (2.5%, 5%, 7.5%, and 10%). The physical properties of treated and untreated Polyurethane-Clay Composite (PU-CC) were examined utilizing buoyancy force, unconfined compressive strength (UCS), and direct shear strength, respectively. The result exhibited that the PU-CCTO has the highest buoyancy force at 10% of PU-CCTO10 samples at 50%, followed by 45% of PU-CCTM10 and 8% of PU-CCUN2.5. The UCS and shear strength of PU-CCTO10 are evidently the highest at 300 kPa and 50 kPa, respectively, followed by PU-CCTM2.5 at 130 kPa and 19 kPa and PU-CCUN2.5 at 100 kPa and 15 kPa. PU-CCTO treated by drying oven has the highest buoyancy force at 10% of PU-CCTO10 samples at 50%, followed by 45% of PU-CCTM10 treated by microwave, and the lowest at 2.5 wt% of PU-CCUN2.5 untreated at 8%. In a nutshell, the prospective PU-CCTO is superior to the PU-CCUN and PU-CCTM related of the potential for overheating and burning the PU filler powder during the microwave processing procedure. In conclusion, the 10 wt% of PU filler treated by the drying oven method as a PU clay composite has the potential as an alternative material to improve the compressive strength, shear strength, and buoyancy force in soil improvement.

Analysis of heat transfer and flow over a rotating cylinder at subcritical Reynolds numbers based on Taguchi method

The flow past the rotating circular cylinder and the effect of buoyancy on heat transfer char-acteristics are studied numerically for the Reynolds number of 20 and 40 and the Prandtl number of 0.7. The lift and drag coefficients, Strouhal number, and local Nusselt number on the cylinder are studied under the sway of combined buoyancy (at the Richardson num-ber varies from 0 to 2) and different rotational directions. Although the interaction between buoyancy and rotation is a puzzling heat transfer problem, the direction of rotation is found to have significant effects on the flow patterns and heat transfer rate. The main innovation of the present work is to determine the extreme points of Nusselt numbers when different conditions are applied. For a positive rotation, the maximum local Nusselt number is at θ=225o, and the minimum local Nusselt number is at θ=100o. In contrast, for a negative rotation, the maxi-mum and minimum local Nusselt numbers are at θ=140o and θ=270o, respectively. Applying Taguchi method, it is found that average Nusselt number is more dependent on Reynolds number than other factors. Additionally, it can be concluded that the direction of rotation can be used as a powerful tool to adjust the heat transfer rate and the required value of drag and lift. Consequently, without applying different rotation speeds, it would be difficult to stabilize the flow, and with the aid of Taguchi method, it is determined that rotation is deciding factor in stabilizing flow patterns. The results are in good agreement with the experimental results.

Fluid-flow effects in the reactive decontamination of porous materials driven by chemical swelling or contraction

Following the release of a chemical warfare agent, it is crucial for public health that the affected environment is entirely decontaminated. If the agent has seeped into a porous building material, the decontamination is achieved by applying a cleanser solution to the surface of the porous material, and allowing it to react in, neutralising the agent. Typically, the agent and cleanser solution are immiscible fluids and so the reaction occurs at the fluid–fluid interfaces within the pores. Previous studies have shown that the rate of decontamination of the porous material can depend on both the chemical reaction rate and the transport of cleanser to the reacting interface. These studies have all assumed that the two fluids have the same densities, so that diffusion is the only cleanser-transport mechanism. In this paper, we relax this assumption and investigate the effect of a fluid flow—generated by a change in density of the material (a swelling, or contraction) during the chemical reaction—on the decontamination process. This flow of fluid results in advection as well as diffusion of chemicals. Buoyancy effects are neglected. In particular, we show that when the agent is more dense than the reaction product, the decontamination process is slower, due to the adverse advection effect.

Stochastic models of ventilation driven by opposing wind and buoyancy

Stochastic versions of a classical model for natural ventilation are proposed and investigated to demonstrate the effect of random fluctuations on stability and predictability. In a stochastic context, the well-known deterministic result that ventilation driven by the competing effects of buoyancy and wind admits multiple steady states can be misleading. With fluctuations in the buoyancy exchanged with an external environment modelled as a Wiener process, such systems tend to reside in the vicinity of global minima of their potential, rather than states associated with metastable equilibria. For a heated space with a leeward low-level and windward high-level opening, sustained buoyancy-driven flow opposing the wind direction is unlikely for wind strengths exceeding a statistically critical value, which is slightly larger than the critical value of the wind strength at which bifurcation in the deterministic system occurs. When fluctuations in the applied wind strength are modelled as an Ornstein–Uhlenbeck process, the topology of the system’s potential is effectively modified due to the nonlinear role that wind strength has in the equation for buoyancy conservation. Consequently, large fluctuations in the wind of sufficient duration rule out the possibility of sustained ventilation opposing the wind direction at large base wind strengths.

Forecast Study on the Overall Coefficient for Passage of Single-Phase and Passage of Single-Phase in an Annular to Plain Tubes Heat Stream

Abstract To prevent buoyancy effects from increasing the overall heat transfer coefficient due to low heat flux, smooth vertical circular tubes require forced convection conjectures. Previous research has focused on mixed convection in turbulent regions and has limited studies on forced convective heat transfer. This study aims to investigate the predictable overall coefficients of heat transfer performance under specific conditions of forced convection, considering both vertical up flow and down flow through the smooth circular test section. The recommended Reynolds numbers for water are (7201.6–14577.4) and (3186.7–6396.75) for single-phase and single-phase annular passages, respectively, with a heat application range of (50–500 W). The overall coefficient of heat transfer is (333.91 - 432.95 W/m2.K) and (169.76 - 251.20 W/m2.K) for single-phase and single-phase annular passages, respectively. The flow was turbulent for all heat fluxes.

The investigation of hydrogen released on the mixed jets with an axisymmetric jet and an asymmetric jet

Hydrogen released from complex multi-pipeline leakage sources can increase the difficulty of predicting the risk region of hydrogen and the probability of explosion accident. To investigate the collision and mixing features of subsonic hydrogen jets released from multi-pipeline leakage sources, an experimental platform for gas visualization and quantitative measurement is constructed. The differences in flow field structure and concentration distribution of vertical axisymmetric hydrogen jet, vertical asymmetric hydrogen jet and mixed hydrogen jets are compared and analyzed. Furthermore, the effects of multiple factors on the jet centerline, concentration decay, hazardous volume and diffusion height of the mixed region are predicted. The numerical simulation results are verified by the experimental data. Results indicate that the asymmetric hydrogen jet causes the mixed region centerline of hydrogen to deviate from the vertical axis under the combined effect of momentum-dominant and buoyancy. With the increase of the volumetric flow rate, the slope of the mixed region centerline initially decreases and then increases, with the smallest slope occurring at a volumetric flow rate of 159 NL/min. Either the increase of the leakage orifice diameter or the decrease of the distance between two leakage orifices can cause the slope of the mixed region centerline to decrease. Among three factors, the leakage orifice diameter has the most obvious effect on the concentration decay. The hydrogen diffusion height gets the highest when the ratio of leakage orifice diameter to pipeline inner diameter is 0.4 among five leakage orifice diameters. The distance between two leakage orifice has no significant influence on the hazardous volume. The investigation provides valuable data to support the prediction of the dangerous range of hydrogen leakage in complex multi-pipeline leakage sources.

A qualitative study of mixing a fluid inside a mechanical mixer with the effect of thermal buoyancy

A qualitative study of mixing a fluid inside a mechanical mixer with the effect of thermal buoyancy

Transient Dynamics in Counter-Rotating Stratified Taylor–Couette Flow

This study focuses on the investigation of stratified Taylor–Couette flow (STCF) using non-modal analysis, which has received relatively limited attention compared to other shear flows. The dynamics of perturbations under different temperature conditions are explored, and their patterns of amplification are analyzed. The study highlights the correlation between flow configurations, emphasizing the similarity in transient dynamics despite different speed ratios. The subcritical effects of thermal stratification on disturbance dynamics are examined, considering the interplay between viscous and buoyancy effects counteracted by strong centrifugal forces. It is found that increasing the wall temperature beyond a critical value leads to buoyancy forces dominating, resulting in a linear increase in the amplification factor. The research reveals significant deviations from previous results, indicating the significant role of temperature stratification.

Influence of GI configurations and wall thermal effects on flow structure and pollutant dispersion within urban street canyons

Numerous evidence has shown that within the semi-enclosed street canyon, traffic emissions and the secondary pollutants are prone to accumulating in poorly ventilated areas, which is a serious threat to people's health. Among many factors affecting the flow field and pollution diffusion characteristics in street canyon, the effects of wall thermal buoyancy caused by solar radiation coupled with the aerodynamics and shading effect of different forms of green infrastructures (GIs) have not been paid enough attention. This study conducted the numerical simulations validated by wind-tunnel experiments to investigate the influence of different GIs & wall heating (WH) conditions on flow and dispersion within urban street canyons. Eight GIs and four WH configurations are considered. The validation results indicate that SKE-SWFs have better prediction accuracy. Numerical results show that the green belt has little effect on flow and dispersion within street canyon, while other GIs will cause increased pollution on the leeward side to varying degrees, depending on the planting location and volume of tree crown. Under the WWH, the RSTs will lead to the reverse flow at the canyon bottom, so that the pollutants will completely turn to the windward side. Conversely, the LSTs can promote the migration of pollutants to the canyon center, and has little impact on two side walls and pedestrian respiration planes, therefore, the LSTs is suggested to be the optimal tree planting configuration. This study can provide technical guidance for the optimization design of urban green facilities to achieve well-targeted control of local air quality.

Influence of buoyancy and viscous dissipation effects on 3D magneto hydrodynamic viscous hybrid nano fluid ([formula omitted][formula omitted] under slip conditions

Owing to its bounteous applications in engineering and advanced industrial processes magnetized hybrid Nano fluid influenced by suspended Nano-size particles got unusual consideration. The prime focus of current study rely on the meaningful investigation of the proposed phenomena with the utilization of buoyancy and viscous dissipation influence in the hybrid fluid. Numerical approach appertaining to three-dimensional hybrid Nano fluid flow configured by horizontal stretched surface is developed in the contemporary study. Magneto hydrodynamic viscous flow demeanor of hybrid traditionally water-based Nano fluid is contemplated in current report. Heat transmission phenomenon is taken into consideration on account of suspended Nano-scale size particles namely Magnesium-oxide (MgO) and Titanium-oxide (TiO2). Furthermore, Viscous dissipation along with thermal radiation impacts are also opted for the optimization of energy. Velocity profile along x-component and y-component is observed under buoyancy effects. Cartesian coordinates system have been accounted to mathematically model the proffered nonlinear system of PDEs by invoking appropriate similarity approach. An esteemed and prominent Runge-Kutta (4th - order) established on shooting technique is employed for the determination of velocity as well as temperature distributions. Multifarious parameters influence is sketched graphically. Velocity profile along horizontal components demonstrates the strengthening behavior for the growing values of magnetic parameter M and also buoyancy parameter λb while demonstrates depreciating behavior for the enhanced values of slip parameter K and also rotation parameter λ. Moreover, velocity profile along the vertical components is observed under the consequences of varying values of magnetic parameter M, rotation parameter λ, and slip parameter K and for buoyancy parameter λb.We noticed that horizontal component depicts enhanced demeanor for magnetic parameter M, slip parameter K whilst decaying demeanor for the upshot vales of rotation parameter λ. Local Skin-friction and also Nusselt number influence is reported via tables and found in excellent accuracy. The final outcomes will be validated numerically by aiding suitable techniques (R–K 4th order based Shooting Method). Our findings will be validated through graphs. This research provides significant field of study and will play an extensive role in field of fluid mechanics.

Effect of variable viscosity on oscillatory heat and mass transfer in mixed convective flow with chemical reaction along inclined heated plate under reduced gravity

Reduced gravity refers to the actual decline in the accelerated motion of gravitation that occurs when a particular fluid comes into contact with another fluid that has different densities as a result of buoyant effects. The reduced gravity mechanism is very affective along the inclined geometries to reduce more gravitational pressure. In comparison to ordinary action of gravity, reduced gravity was reported to demonstrate less heat transfer, which helped to thicken the liquid layers. The main objective of this study is to illustrate the effects of chemical reaction and variable viscosity on oscillatory behavior of heat and mass transfer along an inclined heated plate under reduced gravity. The viscosity of fluid is assumed as a function of temperature. The mathematical model is developed in terms of partial differential equations and converted into steady and oscillating part by using oscillating Stokes conditions. The primitive variable formulation is used to convert steady and oscillating part into convenient form for smooth algorithm. The numerical results are deduced in tables and graphs with the help of FORTRAN and Tecplot 360. The velocity, temperature distribution, concentration profile, oscillatory skin friction, heat transfer and mass transfer are plotted for various governing parameters. The range of parameters has selected according as Prandtl number 0.1≤Pr≤7.0, buoyancy parameter 0<λT,λC<∞, Schmidt number 1.0≤Sc≤6.0, 0.1≤Rg≤8.0 and the choice of reaction rate parameter set the effects of chemical reaction respectively. The results show that the velocity profile increases as viscosity decreases under reduced gravity. It can be seen that temperature profile decreases as reduced gravity increases with lower viscosity. It is noticed that the heat and mass transfer increases with significant amplitude in the presence of reduced gravity and chemical reaction.

Analysis of inclined magnetized unsteady cross nanofluid with buoyancy effects and energy loss past over a coated disk

The current study presents an analysis of an inclined magnetized unsteady Cross fluid flowing over a coated disk with buoyancy effects and energy loss. The flow is modeled using the Navier-Stokes equations, including buoyancy, magnetic field, and energy loss effects based on the coated disk. The governing equations are solved numerically by applying the process of bvp4c to analyze the effects of inclination angle, magnetic field strength, and coating thickness using the flow characteristics. The results indicate that the buoyancy effects have a significant impact on the flow along with the results of flow velocity increment along with static pressure decrement. The magnetic field also has significant effects on the flow, which shows the decreasing velocity by increasing the magnetic field. Additionally, the coating thickness has significant effects on energy loss that decrease by increasing the coating thickness. The purpose of this work is to provide the valuable insight using the buoyancy, magnetic field, and coating thickness effects on the flow characteristics and energy loss based on the inclined magnetic unsteady cross flow passing over a coated disk.

Effect of composition on nucleation and growth of equiaxed dendrites in the transparent alloy Neopentylglycol-(d)Camphor during solidification in microgravity conditions

We investigate the effect of composition of hypoeutectic Neopentylglycol-(D)Camphor (NPG-DC) alloy on nucleation and microstructure kinetics during alloy solidification in low gravity conditions without convection and buoyancy effects. Two alloys with compositions of 0.2 and 0.3 wt-frac. DC have been solidified in a small thermal gradient to obtain equiaxed dendritic microstructures with different crystallographic growth orientation. In-situ optical and thermal characterization in the transparent material provided evolution of equiaxed dendrite density, nucleation undercooling, dendrite tip velocity and kinetic law. Significant differences in the results for the two compositions were found, which are discussed in relation to temperature and concentration dependent solid–liquid interfacial properties. For NPG-0.2 wt-frac. DC equiaxed dendrites with 〈100〉 crystallographic growth orientation exist which tend to grow faster and fill the liquid volume quicker compared to the NPG-0.3 wt-frac. DC alloy. This behavior hinders nucleation of further dendrites and decreases their final number. In contrast, for NPG-0.3 wt-frac. DC equiaxed dendrites with 〈111〉 crystallographic growth orientation nucleate at higher undercooling and the kinetic law indicates smaller dendrite tip velocities correlated to a larger number of dendrites.