Water Flow Characteristics Research Articles

Enhancing convective heat transfer for laminar flow in a tube by inserting a concentric inner tube and controlling concurrent flows: a numerical assessment

The present study demonstrates, via a numerical simulation, the feasibility of achieving enhanced forced convection heat transfer of laminar water flow in an isoflux heated circular tube by inserting a concentric circular tube and controlling the concurrent flow distribution through the resulting concentric double-tube duct. Under identical operation conditions to those for the parent single-tube flow configuration, including the inlet fluid temperature, the total volumetric flow rate, the length of heated section, as well as the wall heat flux imposed, numerical simulations have been undertaken for the thermally developing convective heat transfer characteristics of water flow in the concentric double-tube duct featuring geometrically by three different relative radius ratio ro (= 1.2, 1.5, 1.8), compared with its parent single-tube duct of lh,ST = 0.1 at ReST = 100, 500, and 1000, respectively. In terms of the local and length-averaged heat transfer effectiveness gauged against that obtained for the parent single-tube duct, numerical results clearly demonstrate that the double-tube duct of smaller ro operating with relative larger flow rate than that in the inner tube can serve as highly effective heat transfer enhancement configuration.

Numerical investigation of heat transfer and friction characteristics for turbulent flow in various corrugated tubes

Thermal and hydraulic characteristics of turbulent water flow in a transverse corrugated tube with various corrugation direction (inward/outward) and corrugation shape (triangle, curve, rectangle, and trapezoid) are numerically investigated. The axisymmetric model of corrugated tubes with 10 mm inner diameter was investigated by changing the geometrical parameters for Reynolds number ranging from 5000 to 61,000 and constant heat flux boundary condition. Structured, nonuniform grid system is applied. Momentum, continuity, and energy equations were treated by means of a finite volume method using the SIMPLE scheme with the k–ε turbulence model and enhanced wall treatment. The results reveal that corrugation direction and corrugation shape have perceptible effects upon the heat transfer in the form of Nusselt number ( Nu) and pressure drop in the form of friction factor (ƒ). The average Nu for (inward) trapezoidal, rectangular, curved, and triangular corrugation shapes are 52.61%, 50.12%, 47.82%, and 44.96%, respectively, higher than the smooth tube. The average Nu for (outward) trapezoidal, curved, triangular, and rectangular corrugation shapes are 48.31%, 45.72%, 41.23%, and 40.94%, respectively, which are higher than a smooth tube. The results reveal that both inward/outward curved and triangular roughness shape have the superior performance evaluation criterion than rectangular and trapezoidal. Turbulence kinetic energy contour shows the increase in heat transfer performance for all corrugated tubes compared with a smooth tube. Inward corrugated tube provides the highest turbulence kinetic energy along the tube length and, consequently, the highest heat transfer. In addition, inward corrugated tubes provide the highest values and homogeneity of the velocity distribution along the core of tubes.

Effect of MHD on the flow and heat transfer characteristics of nanofluid in a grooved channel with internal heat generation

Purpose The purpose of this study is numerical simulation of magnetohydrodynamics (MHD) water–Al2O3 nanofluid mixed convection in a grooved channel with internal heat generation in solid cylinders. Simulations were carried out at Reynolds numbers 50 ≤ Re ≤ 100, Hartmann numbers 0 ≤ Ha ≤ 15, Grashof numbers 5,000 ≤ Gr ≤ 10−4 and volume fraction 0 ≤ φ ≤ 0.04. The effect of Reynolds number and the influence of magnetic field and pressure drop on convective heat transfer coefficient were studied in different volume fractions of nanoparticles at different Reynolds numbers. Design/methodology/approach The results show that average Nusselt number increases by increasing Reynolds and Hartman numbers. Also, when Hartman number increases, velocity profile becomes asymmetric. Pressure distribution shows that magnetic field applies Lorentz force at opposite direction of the flow, which causes asymmetric distribution of pressure. As a result, pressure in the upper half of the cylinder is higher than the lower half. Finally, velocity and temperature contours along the channel for different Hartmann numbers, volume fraction 3 per cent, Re = 50 and 100 and Gr = 10,000, are presented. Findings The effect of Reynolds number and the influence of magnetic field and pressure drop on convective heat transfer coefficient were studied in different volume fractions of nanoparticles at different Reynolds numbers. Originality/value Effect of MHD on the flow and heat transfer characteristics of Water–Al2O3 nanofluid in a grooved channel with internal heat generation in solid cylinders.

Variable Fluid Property Effect on Heat Transfer and Frictional Flow Characteristics of Water Flowing through Microchannel

The effects of temperature-dependent viscosity and thermal conductivity on heat transfer and frictional flow characteristics of water flowing through a microchannel are numerically investigated in this work. The hydrodynamically and thermally developing flow with no-slip, notemperature jump, and constant wall heat flux boundary condition is numerically studied using 2D continuum-based conservation equations. A significant deviation in Nusselt number from conventional theory is observed due to flattening of axial velocity profile due to temperaturedependent viscosity variation. The Nusselt number shows a significant deviation from conventional theory due to flattening of the radial temperature profile due to temperature-dependent thermal conductivity variation. It is noted that the deviation in Nusselt number from conventional theory is maximum for combined temperature-dependent viscosity and thermal conductivity variations. The effects of temperature-dependent viscosity and thermal conductivity on the Fanning friction factor are also investigated. Additionally, the effects of variable fluid properties on Poiseuille number, Prandtl number, and Peclet number are also investigated.

Modelling the promotion effect of vegetation on the dissipation of supersaturated total dissolved gas

Flood plays a vital role in aquatic organisms’ subsistence and reproduction. It can bring spawning signals to fishes and excessive foods fattening fishes up in the flood plain. Nowadays, with an increasing number of high dams being put into operation, huge changes have happened in the process of natural flood. In order to maintain the ecological function of flood, sometimes hydropower stations have to make artificial flood peak by the power station’s spillway discharging. Water discharge from high dams leads to the supersaturation of total dissolved gas (TDG), thus causing fish to suffer from gas bubble disease (GBD) and even death. The downstream water level rises during the period of discharge, inundating part of the vegetation on the bottomland. The existence of vegetation can affect the hydrodynamic characteristics of flood water flows and then change the transportation and dissipation of the supersaturated TDG. The stems and leaves of the submerged vegetation provide a large amount of solid-liquid interfaces, which adsorb gas dissolved in water, consequently influencing the dissipation process of supersaturated TDG. In this paper, research about the effect of vegetation on supersaturated TDG is conducted underpinned by laboratory mechanism experiments. The supersaturated TDG dissipation process with vegetation existing in the water was obtained. The results indicate that planting vegetation in water can effectively bolster the releasing of TDG, and as the density of vegetation increases, the promotion effect is commensurately enhanced. Based on the experimental data, this paper proposes a supersaturated TDG dissipation model describing the function of the vegetation’s wall adsorption of the TDG, and the formula for the adsorption flux Fa of supersaturated TDG in a unit area over a unit time is achieved. This paper obtains a significant parameter representing how fast the vegetation’s surfaces adsorb the supersaturated TDG, namely, the adsorption rate ka. It is determined that ka is solely related to the vegetation’s material and surface characteristics.

Experimental Study of Water Flow and Heat Transfer in Silicon Micro-Pin-Fin Heat Sinks

An experimental study is performed to investigate water flow and heat transfer characteristics in silicon micro-pin-fin heat sinks with various pin–fin configurations and a conventional microchannel, with a length of 25 mm, a width of 2.4 mm, and a height of 0.11 mm. The micro-pin-fin heat sinks have different fin arrangements, fin shapes, and fin pitches. The results show that the micro-pin-fin heat sinks have the better overall thermal-hydraulic performance including the heat transfer enhancement and the pressure drop penalty compared to the conventional microchannel. A parametric study is carried out to investigate the effects of various pin-fin configurations on the flow and heat transfer characteristics. The linear relationship between fRe and Re is found for the water flow through the micro-pin-fin heat sinks for the first time. A new friction factor correlation is further developed based on the linear relationship between fRe and Re. Taking the effects of the various pin-fin configurations on the Nusselt number into consideration, a new Nusselt number correlation is also developed. The new correlations of friction factor and Nusselt number predict the experimental data well. An infrared thermo-imaging system was used to measure the temperature field of water heat transfer in the micro-pin-fin heat sinks and the conventional microchannel. The infrared thermo-images show the more uniform temperature profile in the transverse direction for the micro-pin-fin heat sinks than that for the conventional microchannel, which indicates the better heat transfer performance of the former than the latter. The dominant mechanism of heat transfer enhancement caused by the micro-pin-fins is the hydrodynamic effects, including fluid disturbance as well as the breakage and re-initialization of the thermal boundary layer near the wall of the heat sinks.

Single phase laminar fluid flow and heat transfer in microchannel with cylindrical and parallelepiped micro-fins

In this paper, the fluid flow and heat transfer characteristics of water as coolant in cylindrical and parallelepiped micro-finned rectangular microchannels are investigated. Experiments are performed on a copper plain microchannel with six parallel channels of dimensions 350 (width) × 605 (depth) μm for Reynolds number in the range of 67 to 153 and four different heat inputs. Experimental results are used to validate the numerical model, which is extended to analyze the effects of diameter of cylindrical and length and width of parallelepiped micro-fins on the overall performance of microchannel using non-dimensional parameters, such as Poiseuille number, Nusselt number and performance evaluation criteria. It is found that the enhancement in heat transfer is higher than that of pressure drop. Smaller diameter cylindrical fin performs better than the plain channel, when the performance is evaluated considering both heat transfer and pressure drop in channels. Correlations are developed for Poiseuille number and Nusselt number for cylindrical and parallelepiped micro-finned rectangular channels, which can be used to design microchannel with extended surface for thermal management of electronic devices.

The flow and heat transfer characteristics of supercooled water based on the nano-superhydrophobic surface

Dynamic ice making by supercooled water is one of the most promising ways to produce ice slurry at present. However, its main defect is that the supercooler is easy to have ice blockage. A nano-fluorocarbon thin film of about 10 nm thickness coated on the solid surface, which is composed of a large number of uniformly distributed tiny bumps and holes, making the coated surface present super-hydrophobicity and the contact angle θ reach 163.01° with a small contact angle hysteresis. Based on the properties of nano-superhydrophobic surface, the characteristics of flow and heat transfer of supercooled water are analyzed in the flow regime with low reaction coefficient. It was found that: due to the existence of “velocity slip” on the nano-superhydrophobic surface, the flow and average flow rate of supercooled water increase, reducing the mechanical energy dissipation in the process of supercooled water flow, and the flow resistance is smaller with a good heat transfer performance. However, whether the effect of the super-hydrophobic surface can enhance or deteriorate the transport mechanisms depending to the flow regime and surface structure.

Effects of solids accumulation and plant root on water flow characteristics in horizontal subsurface flow constructed wetland

Void space clogging of horizontal subsurface flow constructed wetlands (HSSF CWs) can result in hydraulic malfunction and reduced service life. In this study, the effect of solids accumulation and root growth on the hydrodynamics of the HSSF CWs was evaluated by tracer tests. The experimental HSSF CWs were designed to be unplanted, uniformly planted and linearly planted to investigate the role of Iris (I. pseudacorus) root and the effects of different planting patterns. Results showed that the traditional design of HSSF CW was easy to develop the preferential bottom flow, and the solids accumulation near inlet zone aggravated the fast bottom flow throughout the whole systems. Plant root impeded the upper layer flow at the initial stage and promoted the uniform flow in the severe clogging situation. Consequently, the water flow was more uniform in the linearly planted (dispersion number (d) = 0.16) and uniformly planted (d = 0.13) systems than the unplanted system (d = 0.10) at the final stage. The opening of new void spaces by root growth and the upward water drag induced by plant transpiration was responsible for such phenomenon.

A new experimental method for measuring the three-phase relative permeability of oil, gas, and water

For tertiary oil recovery, the gas drive is often implemented after water flooding. The three-phase flow phenomenon of oil, gas, and water exists during the process of gas injection. The three-phase relative permeability should be measured to further study the flow characteristics of oil, gas, and water in porous media. In this work, the steady-state flow method is adopted to establish a combined experimental method based on the principle of relationship between resistivity and water saturation, and the principle of on-line CT scanning is used to measure the three-phase relative permeability. The relative permeability of oil, gas, and water is measured under different saturation histories, including the water alternating gas flooding, in which water saturation decreases, oil saturation decreases, and gas saturation increases, as well as gas alternating water flooding, in which water saturation increases, oil saturation decreases, and gas saturation decreases. The experimental results show that in a water-wet core, the relative permeability of water is a function of its own saturation, and its isoperms are straight lines. The relative permeability of oil and gas phase is affected by their saturation and other phase saturations. In an oil-wet core, the isoperms of oil, water, and gas are convex to the point of 100% their own saturation, which means the relative permeability of oil, gas and water depend on all the three phase saturations. The saturation histories influence the isoperms of the three phases differently. Compared with the two-phase flow, the three-phase flow is more complex. This new experiment provides an approach and theory for the study of three-phase seepage laws in the gas drive.

Direct numerical simulation of a turbulent core-annular flow with water-lubricated high viscosity oil in a vertical pipe

The characteristics of a turbulent core-annular flow with water-lubricated high viscosity oil in a vertical pipe are investigated using direct numerical simulation, in conjunction with a level-set method to track the phase interface between oil and water. At a given mean wall friction ($Re_{\unicode[STIX]{x1D70F}}=u_{\unicode[STIX]{x1D70F}}R/\unicode[STIX]{x1D708}_{w}=720$, where$u_{\unicode[STIX]{x1D70F}}$is the friction velocity,$R$is the pipe radius and$\unicode[STIX]{x1D708}_{w}$is the kinematic viscosity of water), the total volume flow rate of a core-annular flow is similar to that of a turbulent single-phase pipe flow of water, indicating that water lubrication is an effective tool to transport high viscosity oil in a pipe. The high viscosity oil flow in the core region is almost a plug flow due to its high viscosity, and the water flow in the annular region is turbulent except for the case of large oil volume fraction (e.g. 0.91 in the present study). With decreasing oil volume fraction, the mean velocity profile in the annulus becomes more like that of turbulent pipe flow, but the streamwise evolution of vortical structures is obstructed by the phase interface wave. In a reference frame moving with the core velocity, water is observed to be trapped inside the wave valley in the annulus, and only a small amount of water runs through the wave crest. The phase interface of the core-annular flow consists of different streamwise and azimuthal wavenumber components for different oil holdups. The azimuthal wavenumber spectra of the phase interface amplitude have largest power at the smallest wavenumber whose corresponding wavelength is the pipe circumference, while the streamwise wavenumber having the largest power decreases with decreasing oil volume fraction. The overall convection velocity of the phase interface is slightly lower than the core velocity. Finally, we suggest a predictive oil holdup model by defining the displacement thickness in the annulus and considering the boundary layer characteristics of water flow. This model predicts the variation of the oil holdup with the superficial velocity ratio very well.

Thermal and flow characteristics of helical coils with reversed loops

In this experimental study, flow and heat transfer characteristics of water through a newly designed helical coil heat transfer test section were investigated. A structural modification of the traditional helical coil has been implemented to improve its thermal effectiveness. Specifically, a 360° plastic reversed loop was added after each 180° of the main helical coil loop to redistribute the flow’s velocity profile, which should have a direct effect on the thermal performance of the helical coil heat transfer test section. Results reveal that reversed loops do enhance heat transfer rates by more than 20%, while pressure drop penalty also increases but not at the same rate. The curvature of the reversed loops with respect to the main coil is a critical factor in terms of thermal performance. Furthermore, as the size of the reversed loop decreases, the heat transfer enhancement and pressure drop penalty increment for the modified helical coil test section increase as well. Accordingly, it is suggested that there may exist an optimum helical coil structural modification for which the best tradeoff between pressure drop penalty and heat transfer enhancement can be found.

Numerical analysis of gas-liquid two-phase flow after water inrush from the working face during tunnel excavation in a karst region

Increasingly, deep tunnels are under construction, which greatly promotes the development of tunnelling technology. Complex geological conditions and frequent geological disasters have become great challenges during tunnel excavation. Among them, casualties and economic losses caused by water inrush are on the top levels in all types of tunnel geological disasters. In the present study, numerical simulation of the gas-liquid two-phase flow is carried out by using the FLUENT software to probe water flow characteristics after water inrush. Three common cases of water inrush from the working face during double-line tunnel excavation are researched. The variation rules of velocity, pressure and water volume fraction in the tunnels after water inrush are analyzed. The water movement laws under the conditions of different excavation situations and different water inrush positions are further discussed by comparing the three case studies. When water inrush occurs on the left tunnel working face, the following conclusions are drawn: (1) The velocity is smaller at the lower location of the left and right tunnels. In the width direction of the cross passage, the velocity is smaller on the left and right sides of the section, and in the height direction, the velocity is smaller on the upper end and lower end of the cross passage. (2) The pressure decreases gradually with the increase of height in the left tunnel and the cross passage. In the vicinity of the cross passage, the pressure on one side of the left and right tunnels close to the cross passage is the minimum, and then it gradually increases towards the other side. (3) The water volume fraction decreases gradually with the increase of height. (4) The velocity, pressure and water volume fraction changes greatly at the intersection of the cross passage and tunnels. In addition, the velocity nearby the working face without water inrush is very small.

Use of electrical resistivity tomography in selection of sites for underground dams in a semiarid region in southeastern Brazil

A number of geophysical investigations have been carried out over the least two years as part of a study for identifying suitable sites for underground dams in the semiarid region of south east Brazil. The results obtained in the Municipality of Jenipapo de Minas have allowed identification of basement structures beneath shallow soil cover of the intermittent stream Bolas. According to current interpretation of electrical resistivity profiles and pseudo sections obtained in inversion techniques this structure is characterized by a high-resistivity layer (more than 1200Ωm) beneath a low-resistivity surface layer (less than 500Ωm), at depths of 1–5 m. The high-resistivity layer has been interpreted as the top parts of the highly impermeable metamorphic rocks of the basement rocks. The low-resistivity layer is composed mostly of sandy soil in the bed of the Bolas stream. Results of repeat resistivity surveys, carried out during dry and wet seasons, have allowed new insights into the appearances of subsurface channels. Such features are associated with episodes of subsurface flow of water infiltration into the soil layer, during periods of rainy season. It appears that geoelectric surveys may be employed in mapping spatial and temporal characteristics of subsurface water flows, associated with infiltration episodes of meteoric waters into subsoil layers beneath the stream bed. Identification of such features have been found to be useful in selection of suitable sites for grouting the foundation of underground dams in the study area of the present work.

Analog modeling of sand slope stability with different precipitation conditions

Water–sand flow triggered by rainfall is the dominant mechanism for instability and failure of sand slopes. To further analyze the stability state of sand on a slope under different rainfall conditions, the initiation conditions and flow characteristics of water–sand flows are studied. Based on the theory of equilibrium forces and hydrological dynamics, a 1:100-scale analog model is built and verified with field observation data. The results indicate three dynamic stabilization stages of the sand slope under different weather conditions: dry sand, wet sand, and water–sand flow. Water–sand flows are triggered easily under short duration and heavy rainfall conditions. The rainfall threshold required to initiate water–sand flow is 4.14 mm/h. Rainfall amount and duration required to initiate water–sand flow decrease with fine sand content increasing. A sand head that develops at the front of the water–sand flow results in a flow along the edge of the sand debris flow and a “tree root” flow morphology. Modeling results are consistent with theoretical analysis and field observations.

Refined dependences of power-law form for calculation of hydraulic resistance and velocity distribution

To solve the engineering problems of hydraulic engineering, water supply and sanitation, prevent emergency situations at hydraulic structures, regulate channel processes, efficient ecological monitoring of water bodies, and develop measures that exclude crisis ecological situations, more and more accurate estimates are required for the hydraulic characteristics of water flows. Inaccurate assumptions and approximate methods of integration can lead to significant errors that significantly affect the results of predicting flooding of riverine areas; this requires further refinement of the calculation methods. Until now, theoretical and experimental substantiations of the basic propositions of the theory of turbulence, hydraulic resistances, channel processes cannot be considered sufficiently complete. The compositions of problems associated with flows in wide channels, problems of turbulence, ax symmetric flows in smooth and rough pipes, are of scientific and practical interest. The article investigates the dependencies for the calculation of kinematic and dynamic flow characteristics in deformed and undeformable boundaries. New formulas are given for a refined description of the distribution of flow velocities and hydraulic resistance of turbulent flows in pipes and channels. Based on the known fundamental research, the calculation-theoretical methods are refined. The results obtained for flows in non-deformable channels can be useful for estimating not only flow in pipes, but also river flows in hard, undeformable boundaries and with minor channel deformations (in channels and rivers). For the first time, the analysis made it possible to obtain power-law approximations of the resistance laws for smooth and rough tubes and to establish the actual relationship between the exponents in the velocity profile and the law of resistance.

Lattice Boltzmann simulation of liquid flow in nanoporous media

In this paper, a multi-relaxation-time lattice Boltzmann (LB) model for nanoscale liquid flow is established to investigate the liquid flow characteristics in nanoporous media. The slip length and effective viscosity obtained by molecular dynamics (MD) simulations are adopted to account for the nanoscale effect. First, the LB model for water flow in nanopores is built and water flow characteristics in nanoporous media are investigated. The fluid-solid interaction force shows significant influence on water flow in nanoporous media. The water flux through nanoporous media increases with the decrease of fluid-solid interaction force. In hydrophobic nanoporous media, the nanoscale effect can decrease the gap between water flow resistance in large pores and that in small pores, making the velocity distribution more uniform. In addition, the end effect caused by the bending of streamlines can induce significant additional flow resistance. Neglecting the end effect can greatly overestimate water flow ability. The pore structure also has significant influence on water flow in nanoporous media. With the increase of specific interfacial length, the nanoscale effect increases. Finally, the LB model for oil (octane) flow in quartz nanopores is also established by incorporating the MD simulation results. Oil flow simulation in quartz nanoporous media shows that the conclusions obtained for water flow are also applicable for oil flow.

Thermal and Flow Characteristics of Water–Nitrogen Taylor Flow Inside Vertical Circular Tubes

Heat transfer and flow characteristics of Taylor flows in vertical capillaries with tube diameters ranging from 0.5 mm to 2 mm were studied numerically with the volume of fluid (VOF) method. Streamlines, bubble shapes, pressure drops, and heat transfer characteristics of the fully developed gas–liquid Taylor flow were investigated in detail. The numerical data fitted well with experimental results and with the predicted values of empirical correlations. The results indicate that the dimensionless liquid film thickness and bubble rising velocity increase with increasing capillary number. Pressure drops in liquid slug region are higher than the single-phase flow because of the Laplace pressure drop. The flow pattern dependent model and modified flow separation model which takes Bond number and Reynolds number into account can predict the numerical pressure drops well. Compared with the single-phase flow, less time is needed for the Taylor flow to reach a thermal fully developed status. The Nusselt number of Taylor flow is about 1.16–3.5 times of the fully developed single-phase flow with a constant wall heat flux. The recirculation regions in the liquid and gas slugs can enhance the heat transfer coefficient and accelerate the development of the thermal boundary layer.

A Numerical Study on the Flow Characteristics of Water and Soil Slurry in Pipe

This study described the phenomena of transport and sedimentation of soil slurry flowed in storm sewers from the perspective of numerical analysis. There have been some research cases reviewing the characteristics of flows inside of storm sewers. Most existing researches have performed experiments and analyses based on a flow of single fluid in conduits. However, this study tried to interpret such a flows as a two-phase flow by taking into account soil slurry, and it also tried to deduce results on the change of flow velocity and volume fraction, as well as characteristics of sedimentation to study the tendency of transport and sedimentation inside of the conduits. In addition, it should be necessary to produce theories and analytical basis which can support design criteria for sedimentation inside of conduits based on the analysis of internal flows in storm sewers. Because of difficulties in observing and interpreting two-phase flows made of soil slurry, there have been few studies on this subject, the objective of this study was to examine this part. Accordingly, in case of soil slurry flowed into real manholes, this study reviewed the characteristics of flows generated inside of conduits by reflecting the rate of flow caused by outflow and that of inflow occurred in mixed forms. This study also checked the scope of impact of discharge capacity caused by sedimentation occurred inside of conduits, and improved the already proposed prediction model of critical sediment depth within storm sewers. When comparing with the proposed model, it was confirmed that this new model showed higher correlation ratio. Keywords: Numerical Analysis, Soil Slurry, Transport, Sedimentation, Two-phase Flow, Discharge Capacity

Similitude analysis on flow characteristics of water, A356 and AM50 alloys during LPC process

The present work endeavours to map mold filling characteristics of water to real melts of A356 aluminium alloy and AM50 magnesium alloy during low pressure casting process (LPC). The analogy of dynamic similitude has been applied on a benchmarked computational fluid dynamics (CFD) based simulation model developed for tracking fluid free surfaces. Scaling factors for A356 and AM50 melts with respect to water are calculated by equating the non-dimensional numbers deduced from forces acting on the fluids. Buckingham's Pi theorem is used to verify the derived scaling equations. The mold filling time for water in the benchmarked simulation model and for real alloy melts in the scaled computational models is compared for different inlet pressure regimes. The proposed analogy is verified using variations occurring in velocity scaling factors for the melts during mold filling.