Constant Reynolds Number Research Articles

Numerical simulation analysis of turbulent pulsation drag reduction at different intermittent times

The shear stress generated by wall turbulence is the main cause of wall friction resistance in turbulent flow through pipes. This paper investigates the impact of inserting rest periods (regions of constant Reynolds number) within the pulsating operating cycle of velocity on the fully turbulent flow at large time-averaged Reynolds numbers, using the large eddy simulation (LES) method. The study aims to explore the effect of increasing rest periods within pulsations on drag resistance. The dimensionless shear stress and drag reduction rates during different time periods of rest were analyzed. Numerical simulation results indicate that the pulsating velocity operation mode does not necessarily lead to drag reduction; it may even result in increased resistance. Inserting rest periods within the pulsation cycle can achieve drag reduction effects, with the maximum drag reduction rate reaching 21.8%. This paper utilizes large eddy simulation (LES) to compare and validate the feasibility of LES for pipe pulsating operation modes against experimental results and direct numerical simulation (DNS) results from the literature, providing a rationale and proof of concept for further in-depth studies on other pipe pulsating flows.

Determination of unsteady wing loading using tuft visualization

Unsteady separated flow affects the aerodynamic performance of many large-scale objects, posing challenges for accurate assessment through low-fidelity simulations. Full-scale wind tunnel testing is often impractical due to the object’s physical scale. Small-scale wind tunnel tests can approximate the aerodynamic loading, with tufts providing qualitative validation of surface flow patterns. This investigation demonstrates that tufts can quantitatively estimate unsteady integral aerodynamic lift and pitching moment loading on a wing. We present computational and experimental data for a NACA0012 wing, capturing unsteady surface flow and force coefficients beyond stall. Computational data for varying angles of attack and Reynolds numbers contain the lift coefficient and surface flow. Experimental data, including lift and moment coefficients for a tuft-equipped NACA0012 wing, were obtained at multiple angles of attack and constant Reynolds number. Our results show that a data-driven surrogate model can predict lift and pitching moment fluctuations from visual tuft observations.

Measurement of local Nusselt number and local recovery factor for impinging multiple compressible jets

In the present study the appropriate reference temperature is identified for the compressible impinging jet. Using the measured reference temperature, local recovery factor is calculated. The steady state thin metal foil technique is used for the measurement of target plate temperature. In this study, the effect of Mach number (Ma) at a constant Reynolds number (Re) and the combined effect of Mach number and Reynolds number on the heat transfer rate are investigated. For both the cases, jet-to-plate distance is varied from z/d = 5 to 12. For the first case (effect of Mach number at a constant Re = 20,000), Ma is varied from 0.15 to 0.85. In the second case (combined effect of Mach number and Reynolds number), Ma is varied from 0.2 to 0.78 and the corresponding Re variation is 7200 to 29,000. At a constant Reynolds number, the heat transfer coefficient increases with the increase in the Mach number. For a given Mach number and Reynolds number, the heat transfer rate decreases with the increase in the jet-to-plate distance. The recovery factor remains unaffected by the Mach number and jet-to-plate distance in the case of the concurrent variation of the Mach number and Reynolds number.

Experimental and numerical study of H[formula omitted] enrichment on swirl/bluff-body stabilized lean premixed n-butane/air flame

This study focused on the stabilization of lean premixed flames of n-butane/H2/air with swirl/bluff-body. The research explored four different hydrogen fractions (0, 20%, 40%, and 80%) at a constant equivalence ratio and Reynolds number. The turbulent reacting flow was resolved using a combination of Delayed Detached Eddy Simulation (DDES) and Flamelet Generated Manifold (FGM) model. The velocity fields and reaction zones were obtained through Particle Image Velocimetry (PIV) and OH* chemiluminescence measurements respectively. H2 addition to n-butane significantly enhanced flame characteristics. The chemiluminescence imaging showed that the flame base became stronger with increasing hydrogen addition, reducing the risk of flame lift-off. Hydrogen addition not only increased the overall reaction rate but also changed the combustion intensity at the nozzle exit from weak to strong, which is crucial for flame stabilization. Interestingly, no flashback was observed even at 80% H2 addition to n-butane at the same level of power rating. The flow strain rate analysis of the PIV measurements showed that the inclusion of hydrogen skewed the strain rate probability density functions towards the positive side, indicating an increase in the burning rate. The results demonstrate a progressive increase in preferential diffusion of H2 from reactants to products as the H2 enrichment in the fuel rises and resulted in a more intense flame. Also, the present simulation results were validated with the PIV data, and they showed good agreement. Specifically, an 80% H2 blend exhibited a 16% peak enhancement in flame surface density compared to pure n-butane while concurrently reducing CO2 emissions by 23.2%. The incorporation of H2 also led to the increased vortex strength and strain rate within the flame.

Large eddy simulations of flow over additively manufactured surfaces: Impact of roughness and skewness on turbulent heat transfer

Additive manufacturing creates surfaces with random roughness, impacting heat transfer and pressure loss differently than traditional sand–grain roughness. Further research is needed to understand these effects. We conducted high-fidelity heat transfer simulations over three-dimensional additive manufactured surfaces with varying roughness heights and skewness. Based on an additive manufactured Inconel 939 sample from Siemens Energy, we created six surfaces with different normalized roughness heights, Ra/D=0.001,0.006,0.012,0.015,0.020, and 0.028, and a fixed skewness, sk=0.424. Each surface was also flipped to obtain negatively skewed counterparts (sk=−0.424). Simulations were conducted at a constant Reynolds number of 8000 and with temperature treated as a passive scalar (Prandtl number of 0.71). We analyzed temperature, velocity profiles, and heat fluxes to understand the impact of roughness height and skewness on heat and momentum transfer. The inner-scaled mean temperature profiles are of larger magnitude than the mean velocity profiles both inside and outside the roughness layer. This means, the temperature wall roughness function, ΔΘ+, differs from the momentum wall roughness function, ΔU+. Surfaces with positive and negative skewness yielded different estimates of equivalent sand–grain roughness for the same Ra/D values, suggesting a strong influence of slope and skewness on the relationship between roughness function and equivalent sand–grain roughness. Analysis of the heat and momentum transfer mechanisms indicated an increased effective Prandtl number within the rough surface in which the momentum diffusivity is larger than the corresponding thermal diffusivity due to the combined effects of turbulence and dispersion. Results consistently indicated improved heat transfer with increasing roughness height and positively skewed surfaces performing better beyond a certain roughness threshold than negatively skewed ones.

Considerations for Compressible Film Cooling: A Computational Study of the Effects of Transonic Flows and Varying Mainstream Mach Number

Abstract Recent evidence suggests that film cooling flows with engine-realistic mainstream Mach number have declined performance in comparison to those with conventional low-speed laboratory conditions. Consideration and understanding of these effects are fundamental to improving film cooling research. This computational study investigates the film cooling performance of a 7-7-7 shaped film cooling hole with respect to varying mainstream Mach number, with constant Reynolds number. The cases studied include mainstream Mach numbers from 0.15 to 0.75, with a fixed, engine realistic, hole Reynolds number of Red=10,100. Significant results are then evaluated against varying stagnation temperature ratio and blowing ratio. The results showed that at a blowing ratio of 1.75, the adiabatic effectiveness declines significantly with increasing mainstream Mach number. The decreased performance is due to supersonic flows and shocks in the film cooling hole that disrupt flow in the diffuser section of the hole. These characteristics are observed across all stagnation temperature ratios considered. In addition to these insights, the study discusses the importance of proper thermal scaling and definition of adiabatic effectiveness when operating at high mainstream Mach number. It is demonstrated that the effects of high-speed flow challenge the efficacy of the conventional parameters used to characterize film cooling performance.

Flow Development Over An SD7003 Airfoil At Different Accelerations From Rest

This work examines the effect of acceleration on the formation of a laminar separation bubble (LSB). The experiments were performed in a water towing tank with an SD7003 airfoil model accelerated from rest to a constant chord Reynolds number. Quantitative flow field measurements were performed using two-component time-resolved Particle Image Velocimetry (PIV) over a range of accelerations. A detailed analysis of the spatio-temporal flow development is conducted focusing on the LSB formation and dynamics. The results provide insight into the mechanism of LSB formation. The associated transient flow development is shown to persist over several convective time units after steady state free-stream velocity is reached, with no significant effect of acceleration on the overall transient duration. However, the acceleration rate has a substantial effect on flow development during the acceleration phase.

Nanofluid heat transfer enhancement in microchannels: Investigating phases interactions using multiphase Eulerian model

This study employs a robust multiphase Eulerian model to mimic heat transfer enhancement using nanofluids in a circular microchannel. Unlike the Eulerian models reported in the literature, the current model incorporates phase interactions, and its accuracy is significantly improved by integrating collision viscosity, kinetic viscosity, and frictional viscosity. Comparative analysis against other models like mixture and discrete phase models demonstrates superior performance of the current model, particularly for solid particle volume fractions exceeding 1 %. The model evaluates water-based nanofluids (Ag NPs, MgO, ZnO, Al2O3, ZrO2, SiO2) in circular microchannels. Ag NPs/water excels at low volume fractions and high Reynolds numbers, while MgO/water performs better at higher volume fractions. Moreover, the analysis of the Euler number indicates a decreasing trend with increasing Reynolds number across all nanofluids. However, no notable variation in the Euler number is observed when maintaining constant volume fraction and Reynolds number. Ultimately, the model is applied to obtain bulk fluid properties, such as viscosity and thermal conductivity, after suspending the nanoparticles. Subsequently, these properties were incorporated into the single-phase model. Utilizing these derived bulk properties was found to substantially enhance the accuracy of the single-phase model, demonstrating its reliability by yielding results within 13.52 % of experimental data.

Influence of freestream turbulence on boundary layer transition over a controlled-diffusion compressor blade

The influence of inlet freestream turbulence (FST) on the boundary layer transition over the suction surface of a controlled-diffusion compressor blade is demonstrated here by employing a well-resolved large-eddy simulation. Inherent to low Reynolds number conditions, a laminar separation bubble (LSB) forms on the suction surface, attributing to substantial flow diffusion. Inlet FST levels ranging from 1.5% to 7.6% are systematically varied, while maintaining a constant Reynolds number based on axial chord and inlet velocity at 2.1 × 105. Transition of the shear layer is initiated via Kelvin–Helmholtz instability with the amplification of selective frequencies until an inlet FST of 2.3%. Secondary instability emerges in the second half of the LSB, attributed to the amplification of perturbations in the braid region, ultimately leading to breakdown near the reattachment. At a moderate FST level of 4.2%, longitudinal streaks in the first half of the blade elongate downstream, causing the LSB to disappear, while the flow becomes inflectional at the mid-chord. Thus, the boundary layer transition in the second half of the blade is attributed to the high receptivity of the inflectional layer and breakdown of streaks, leading to an exponential growth of disturbances. Finally, at an inlet FST of 7.6%, the boundary layer appears pre-transitional in the first half of the blade, exhibiting significant turbulence levels. In the latter half, excitation occurs primarily through the breakdown of streaks, reflecting an algebraic growth of disturbances. Flow features and oscillations in the Nusselt number in this case suggest the outer mode of streak-induced instability.

Effect of ferro nanofluids on mixed convection in an open cavity with phase change material

Numerical analysis of mixed convection flow in an open channel cavity was performed by placing PCM and using ferro nanofluids (water based Fe3O4 nanofluid) with different volume fractions (1.0%, 3.0% and 5.0%) as working fluids. The effect of different Richardson numbers under laminar flow conditions with constant Reynolds number was analyzed to reveal how the nanofluid volume fraction and PCM position in the cavity affect the flow and heat transfer characteristics. The main reason for considering the use of nanofluid as a working fluid with the PCM layer is the thermal control of the cavity. It has been determined that the use of ferro nanofluids has a positive effect on the thermal control of the flow by increasing the thermal energy storage capacity of the PCM. As the Ri number increased, the importance of mixed convection effects increased, and for the highest Ri number, natural convection played a dominant role, causing a 65.5% decrease in the heated wall dimensionless temperature. Since the heat flux applied for pure water at highest Ri number is one third of that applied for 5.0% nanofluid, the specified temperature increase is quite lower by comparing heat flux thanks to the nanofluid high convection capability. Different than pure water, in all PCM cases the rate of melting is higher for 5.0% ferro nanofluid due to the higher convective heat transfer. In the case of the PCM on the bottom wall, the highest thermal energy storage capacity was obtained for each working fluid and 50% more energy was stored compared to the right heated wall at the same Ri number. Moreover, the maximum average Nu number was determined for the bottom heated case and for the same Ri number at 5.0% ferro nanofluid which was obtained approximately twice as much as pure water when flow reached steady state.

A novel design of double pipe heat exchanger with innovative turbulator inside the shell-side space

An innovative category of turbulators is implemented within the shell of a double pipe heat exchanger (DPHE). The impact of these turbulators on thermal performance and entropy generation is scrutinized through three-dimensional numerical simulations. Maintaining a constant Reynolds number of 500 for the fluid flowing within the shell, the tube's Reynolds number varies within the range of 3000 to 13,000. However, a simulation is performed with a shell-side/tube-side Reynolds number of 750/13000 to investigate the effects of shell-side Reynolds number on heat transfer. To enhance simulation accuracy, the thermophysical features of water, serving as the working fluid, are defined as temperature-dependent functions. Additionally, structured computational grids, featuring polyhedral cells forming the turbulators, are employed to discretize the solution domain. A notable concordance between the simulations' findings and existing experimental correlations is observed. The outcomes indicate that incorporating this turbulator type includes swirl flows, leading to a discernible enhancement in thermal performance. Specifically, for the case with three turbulators at Retube = 3000, the Nusselt number and pressure loss of the fluid flow within the shell show increments of 73% and 87%, respectively, compared to the conventional DPHE. The performance evaluation criterion (PEC) for the shell-side fluid attains a value of 1.41.

Legendre wavelet integration operational matrix method for the numerical solution of unsteady MHD nanofluid flow between moving parallel plates

This study proposes a novel method based on Legendre wavelet integration operational matrix for solving a system of nonlinear ODE’s to model the two-phase, unsteady nanofluid flow and heat transfer between parallel plates in presence of magnetic field. To validate the applicability of proposed method, system of nonlinear BVP with exact solutions is employed as a test problem. Test problem results are compared with exact solution, and other numerical methods. The governing equations were then changed using similarity transformation into a set of nonlinear ODE’s. . Following this, the LWOMM is applied for the proposed problem. Findings demonstrated that, for a constant Reynolds number, skin friction coefficient value increases with rising Hartmann and squeezing numbers. Furthermore, it is demonstrated that Eckert number is a reducing function of the squeeze number and Nusselt number is an increasing function of Hartmann number.

Numerical investigation of double-flame hot-water boilers under steady-state operation

This study investigates the optimal arrangement of combustion chambers in double-flame hot-water boilers using computational fluid dynamics (CFD) under steady-state and laminar conditions. The study considers two arrangements: horizontal and vertical. In the horizontal layout, the study tests three vertical distances of Y*=-0.25, 0, and 0.25 from the center of the boiler and three horizontal gap spaces of S*=0.05, 0.1, and 0.15 between two chambers. In the vertical layout, the study examines three vertical distances of S*=0.1, 0.2, and 0.3. The computations for both layouts are conducted for Richardson numbers ranging from 0.1 to 10 under a constant Reynolds number of 50. The Navier–Stokes equations along with the energy equation are implicitly computed based on the finite volume approach for single-phase water flow inside a simplified two-dimensional model. The results are validated for a single-flame hot-water boiler in terms of the Nusselt number and non-dimensional pressure drop, and a good agreement has been achieved. The study shows that the geometric parameters considered in the study, as well as the Richardson number, have significant impacts on the boiler performance. The study finds that the horizontal arrangement with S*=0.05 and Y*=-0.25 offers the highest thermal-hydraulic performance, regardless of the Richardson number.

On the influence of spanwise deformation on lift coefficient and trailing vortices properties at low Reynolds number

We conducted experiments using a single non-deformed and two spanwise deformed wing models for a constant chord-based Reynolds number, Re=20×103. We carried out all experiments to consider several angles of attack α lower than the stall value. The lift forces between non-deformed and spanwise deformed wings present differences depending on the angle of attack. A first finding of the experimental study is that, for smaller values of the angle of attack, e.g., α = 4°, the non-deformed wing case has higher lift values than the highest spanwise deformed wing. However, for larger values of the angle of attack, such as α = 8°, we found a higher lift for the spanwise deformed case. Additionally, velocity fields of the trailing vortex have been taken by two-dimensional particle image velocimetry, finding that both theoretical models by Batchelor [J. Fluid Mech. 20, 645 (1964)] and by Moore and Saffman [Proc. R. Soc. Lond. Ser. A 333, 491 (1973)] can be fitted to experimental measurements obtained from non-deformed and spanwise deformed wing models, the latter model giving the best results for all angles of attack. Finally, we computed the circulation of the trailing vortex using two different methods with the same result and observing that this estimated circulation level directly correlates with the measurement of the lift force.

Modeling of thermal radiation in a participating media with conjugate heat transfer

AbstractModeling a combination of thermal radiation and conjugate heat transfer in a three‐dimensional rectangular domain which has a participating media CO2 flowing through is done numerically in OpenFOAM. The rectangular duct has a vertical step (facing forward to the inlet) which is located at a distance from the inlet (the distance is same as the height of the inlet section). The domain is divided into two regions (namely solid and fluid). Carbon dioxide, a highly absorbing fluid with extinction, is used here as the participating medium. The ability of the code is verified to analyze the thermal radiation in a participating media with conjugate heat transfer. The study was carried out for a constant Reynolds number 250 and a contraction ratio of 0.5. The study focused primarily on the importance of adding thermal radiation on to thermal analysis and the reason behind the Nusselt number variation on different regions of solid–fluid interface. It also discussed the effect of radiative properties, such as optical thickness and linear scattering albedo, on the average convective Nusselt Number.

Numerical simulation of MHD on sudden expansion duct under strong transverse magnetic field

This research delves into the analysis of quasi-two-dimensional flow dynamics in liquid metal confined within a sudden expansion duct, subjected to a strong magnetic field. Utilizing numerical simulations derived from the SM82 model, the study concentrates on examining the magnetohydrodynamic (MHD) responses across a defined range of parameters. These simulations were conducted maintaining a constant Reynolds number (Re), while systematically varying the Hartmann number (Ha) across a spectrum of values [1000, 2000, 5000, 10000, 15000, 20000] to enable a thorough exploration of the magnetic fields influence on the flow dynamics. The outcomes of this study reveal a marked transition in flow behavior corresponding with the escalation in magnetic field strength. Notably, as the magnetic field intensifies, the flow undergoes a transformation from a state of instability to stability. This shift is predominantly characterized by a diminution, followed by a complete cessation, of shear vortex shedding. Additionally, beyond a Ha of 5000 and at a longitudinal position of x = 6, both the velocity and pressure profiles begin to exhibit near-identical and symmetric characteristics. Post the Ha exceeding 1000, the vortex profile demonstrates symmetry about the y=0 axis. These observations significantly enhance the comprehension of MHD fluid dynamics under quasi-two-dimensional conditions.

Analysis of two layered peristaltic-ciliary transport of Jeffrey fluid and in vitro preimplantation embryo development

The analysis of peristaltic-ciliary transport in the human female fallopian tube, specifically in relation to the growing embryo, is a matter of considerable physiological importance. This paper proposes a biomechanical model that incorporates a finite permeable tube consisting of two layers, where the Jeffrey fluid model characterizes the viscoelastic properties of the growing embryo and continuously secreting fluid. Jeffrey fluid entering with some negative pressure gradient forms the core fluid layer while continuously secreting Jeffrey fluid forms the peripheral fluid layer. The resulting partial differential equations are solved for closed-form solutions after employing the assumption of long wavelength. The analysis delineated that increasing the constant secretion velocity, Darcy number, and Reynolds number leads to a decrease in the appropriate residue time of the core fluid layer and a reduction in the size of the secreting fluid bolus in the peripheral fluid layer. Eventually, the boluses completely disappear when the constant secretion velocity exceeds 3.0 Progesterone (P4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$P_4$$\\end{document}) and estradiol (E2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E_2$$\\end{document}) directly regulate the transportation of the growing embryo, while luteinizing hormone (LH) and follicle-stimulating hormone (FSH), prolactin, anti-mullerian hormone (AMH), and thyroid-stimulating hormone (TSH) have an indirect effects. Based on the number and size of blastomeres, the percentage of fragmentation, and the presence of multinucleated blastomeres two groups were formed in an in vitro experiment. Out of 50 patients, 26 (76.5%) were pregnant in a group of the good quality embryos, and only 8 (23.5%) were in a group of the bad quality embryos. The transport of growing embryo in the human fallopian tube and preimplantation development of human embryos in in vitro are constraint by baseline hormones FSH, LH, prolactin, E2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$E_{2}$$\\end{document}, AMH, and TSH.

Effects of Reynolds number and ammonia fraction on combustion characteristics of premixed ammonia-hydrogen-air swirling flames

Several studies have investigated the effects of equivalence ratio and blending ratio in constant power cases for ammonia-based fuels as ammonia is being investigated extensively as an alternative zero-carbon fuel in recent years. However, in many fields, such as power generation, it is common to operate practical equipment at constant Reynolds number (Re) conditions. To that extent, this study investigates the impact of Re (4000 ≤ Re ≤ 7000), equivalence ratio (0.6 ≤ Φ ≤ 1.45), and ammonia volume ratio (0.55 ≤ XNH3 ≤ 0.9) on the combustion characteristics of NH3/H2 swirling flames. To supplement the experimental work, a previously developed Chemical Reactor Network (CRN) has been used to identify the reaction pathways affecting NOx emissions through reaction analysis. Sampled gas analysis (NO, NO2, N2O, NH3) at the exhaust was reported for the first time at a wide range of equivalence ratios and XNH3 at different Re. At constant Re = 6000, NO and NO2 peaked at around Φ = 0.8 – 0.9, while N2O became substantial at Φ ≤ 0.8 and unburnt ammonia became significant at Φ ≥ 1.05. The chemiluminescence images suggested that at Re = 6000, as XNH3 or Φ increases, the NH2* region expands, and reactions occur further downstream. Furthermore, with decreasing XNH3 at Re = 6000 and Φ = 0.9, the system becomes partially abundant in H2 and H but deficient in O2, suppressing the generation of O and OH radicals, and ultimately also suppressing HNO generation. This leads to the N/NH system reactions becoming dominant and increased NO consumption. NO emissions increased steadily with increasing Re at Φ = 0.8, while at stoichiometry, NO emissions remained somewhat unchanged with changing Re. Findings from this study will aid further in the development of carbon-free zero-emissions systems.

Large eddy simulations (LES) of a three-element high-lift wing: Exploring the active flow control (AFC) capabilities

This study presents an aerodynamic analysis of the 30P30N high-lift three-element wing under varying the angle of attack (α = 5°, 9°, and 23°) at a constant Reynolds number (Rec = 750, 000) by means of large eddy simulations (LES). Baseline results were validated against existing literature, demonstrating good agreement. The increase of the angle of attack entails higher values of lift but also, increased values of drag. At α = 23°, a recirculation area appears above the flap, this being the signature of the stall conditions. This is related to the adverse pressure gradient that develops along the main suction side and the separation of the streamlines in its wake. Actuation strategies using synthetic jets were explored to mitigate this flow separation at this angle of attack, and thus, enhance the efficiency of the wing. Three actuation cases with the jets located on the main wing, on the flap, and on both elements at the same time were investigated. While some improvements are observed with the actuation, particularly in the combined actuation case, the overall wing efficiency was only marginally enhanced. Challenges in achieving significant improvements were attributed to complex flow interactions and the dominance of pressure forces, which affect both the lift and the drag coefficients at the same time.

Morphology and turbulent burning velocity of n-decane/air expanding flames at constant turbulent Reynolds numbers

In this work we experimentally investigated the propagation and the turbulent burning velocity of n-decane/air turbulent expanding flames at 423 K and 0.5-3.0 atm, with constant turbulent Reynold number, ReT,flow = (urmsLI)/ν, ranging from 174 to 4712, using a medium-scale, fan-stirred combustion chamber, where urms and LI are respectively the turbulence intensity and the integral length scale, and ν is the kinematic viscosity of a fresh mixture. It was found that the n-decane/air turbulent expanding flame is self-similar, and the normalized turbulent flame propagation speed scales with the turbulent flame Reynold number, ReT,flame = (urms/SL)(〈r〉/δL), to the one-half power for mixtures characterized by non-unity Lewis numbers, where the mean flame radius (〈r〉) is the length scale, and the thermal diffusivity (α = SLδL) is the transport property. The turbulent burning velocity (ST,c=0.5) at the mean progress variable (〈c〉) of 0.5 decreases with the pressure at a constant ReT,flow, following the similar pressure dependence of the laminar burning velocity (SL). The ST,c=0.5/SL of the fuel-rich n-decane/air flame (ϕ = 1.4) is twice larger than that of the fuel-lean mixture (ϕ = 0.8), which would be attributed to the promotion of local burning rates by coupling between the differential diffusion and the turbulent flame stretch on the local flame fronts. In addition, five useful modified correlations for the turbulent burning velocity with the experimental Lewis number (LeBM) consideration were obtained based on the present experimental data of n-decane/air turbulent expanding flames. Particularly, the successful scaling of the modified correlation based on Damköhler's second hypothesis, ST,c=0.5/SL = 1 + 0.115(ReT,flowLeBM−2)0.5, suggesting that the ST,c=0.5/SL is inversely proportional to the LeBM. The importance of using experimental determined values of the Lewis number in the scaling of turbulent burning velocity with the differential diffusion consideration should be emphasized.