Strong Secondary Flow Research Articles

Numerical Study on R32 Flow Condensation in Horizontally Oriented Tubes with U-Bends

In this paper, the flow condensation heat transfer characteristics of R32 in a horizontally oriented tube with a horizontal U-bend (HUB tube) and a horizontally oriented tube with a vertical U-bend (VUB tube) were numerically investigated. The volume of fluid (VOF) multiphase model with the mass transfer assumption by Lee is adopted to simulate the flow condensation behavior of R32, which are validated by well-known empirical correlations. The influence of structural parameters, mass flux and vapor quality on the heat transfer coefficient (HTC) and liquid film distribution is investigated. Meanwhile, the local liquid film thickness (LLFT) and local heat transfer coefficient (LHTC) are also depicted. The phase transition at the U-bend section is captured. Results show that the U-bend has remarkable disturbance on the flow pattern and LHTC due to the effect of centrifugal force where the LLFT is changed, inducing strong secondary flow. The LHTC is increased by a maximum of 8.47% and 11.86% in VUB tube and HUB tube, respectively, when compared to the case in a horizontally straight oriented tube at the same operating conditions.

Research on 3D Design of High-Load Counter-Rotating Compressor Based on Aerodynamic Optimization and CFD Coupling Method

In view of the flow instability problem caused by the strong shock wave and secondary flow in the channel of the high-load counter-rotating compressor, this paper adopts the design method of coupling aerodynamic optimization technology and CFD and establishes a three-dimensional aerodynamic optimization design platform for the blade channel based on an artificial neural network and genetic algorithm. The aerodynamic optimization design and internal flow-field diagnosis of a high-load counter-rotating compressor with a 1/2 + 1 aerodynamic configuration are carried out. The research indicates that the optimized blade channel can drive and adjust the flow better, and the expected supercharging purpose and efficient energy conversion process are achieved by controlling the intensity of the shock wave and secondary flow in the channel. The total pressure ratio at the design point of the compressor exceeds 2.9, the adiabatic efficiency reaches 87%, and the aerodynamic performance is excellent at the off-design condition, which is on the advanced design level of the same type of axial compressor. The established aerodynamic optimization design platform has important practical engineering applications for the development of high thrust-to-weight ratio aero-engine compression systems.

Experimental and Numerical Flow Analysis of an Engine Realistic State-of-the-Art Turbine Rear Structure

Abstract This paper presents experimental and numerical CFD studies of the aerodynamics of a turbine rear structure (TRS). The TRS test geometry is an engine-realistic state-of-the-art design with a polygonal outer case, recessed engine mount bumps, and three different vane types: regular vanes, bump vanes in bump sectors, and thick vanes. Using three different sector types simultaneously was found to be crucial for the inlet boundary conditions. Experiments were performed in a modern rotating test facility with a low-pressure turbine (LPT) stage upstream of the TRS. A Reynolds number of 350,000 was used, representative of a TRS in a narrow-body geared turbofan engine. The TRS performance was analyzed both at on- and off-design conditions, and a thorough side-by-side comparison of CFD and experiments was performed. Static-pressure distributions, turning and outlet flow-angles, wakes and losses, and surface-flow visualizations and outlet total pressure contours are presented. The thick vane showed good aerodynamic performance, similar to the regular vane. For the bump vane, the mount bumps were found to generate additional local separations and secondary flows, resulting in extra losses. In the regions with strong secondary flows, CFD over-predicts the wakes, whereas the wakes around midspan, where secondary flows have a smaller influence, are predicted well.

Numerical investigation for augmentation of performance of solar absorber utilizing perforated tape and nanomaterial

AbstractCurrent work presents the application innovative shape of twisted tape including barriers and holes. This disturber device has been installed inside the absorber tube of solar system and such barriers helps to increment of swirl flow and appearance of holes decrease the resistance of fluid flow. Turbulent regime has been presumed for current usage and finite volume technique has been developed for this problem. Involving the hybrid nanoparticles within the water makes the properties of nanomaterial to increase and correlations based of experimental outputs were applied for predicting the features of carrier fluid. Impacts of height of barrier and number of revolution as well as inlet velocity has been depicted in outputs with considering constant value of heat flux over the top surface. Besides, variable heat flux effect has been utilized to show the behavior of system at various time stages of the day. Involving longer barrier makes the swirl flow to rise and temperature of outer wall decreases. As revolution of disturber tape elevates, the residence time grows and stronger secondary flow can be generated.

Aerodynamic interaction of turbines in a regulated two-stage turbocharging system

Two-stage turbocharging becomes prevailing in internal combustion engines due to its advantage of flexibility of boosting for the variation of operational conditions. Two turbochargers are closely coupled by engine manifolds in the system especially under the requirement of compactness. This paper studies the influence of the interaction of two turbines in a two-stage turbocharging system on the performance. Results show that the performance of low-pressure turbine is highly sensitive to the stage interaction. Specifically, compared with the cases without interaction, the efficiency of low-pressure turbine increases maximumly by 2.8% when the bypass valve is closed, but reduces drastically by 7.5% when the valve is open. Detailed flow analysis shows that the combined results of swirling flow from the high-pressure turbine and the Dean vortex caused by the manifold elbow result in the alleviation of entropy generation in the turbine rotor. However, when the bypass valve is open, interaction of the swirling flow with the injected bypass flow results in strong secondary flow in the volute and distorted inlet flow condition for the rotor, leading to the enhancement of entropy generation in low-pressure turbine. The study provides valuable insights into turbine performance in a two-stage turbocharging system, which can be used for the modeling and optimization of multi-stage turbocharging systems.

Endwall Heat Transfer and Cooling Performance of a Transonic Turbine Vane With Upstream Injection Flow

Abstract Flow fields near the turbine vane endwall region are very complicated due to the presence of high three-dimensional passage vortices and endwall secondary flows. This makes it challenging for the endwall to be effectively cooled by using traditional endwall cooling methods, such as impingement cooling combined with local film cooling inside the vane passage. One effective endwall cooling scheme: coolant injection flow through discrete holes upstream of the vane leading edge on the endwall, has been considered by many gas turbine companies. The present paper focuses on endwall film cooling effectiveness evaluation with upstream coolant injection through discrete holes. Detailed experimental and numerical studies on endwall heat transfer and cooling performance with coolant injection flow through upstream discrete holes are presented in this paper. High-resolution heat transfer coefficient (HTC) and adiabatic film cooling effectiveness values were measured using a transient infrared thermography technique on an axisymmetric contoured endwall. The endwall tested was a scaled up inner endwall of an industrial transonic turbine vane with double-row discrete cylindrical film cooling holes located 0.39Cx upstream of the vane leading edge. The tests were performed in a transonic linear cascade blowdown wind tunnel facility. Conditions were representative of a land-based power generation turbine with exit Mach number of 0.85 corresponding to exit Reynolds number of 1.5 × 106, based on exit condition and axial chord length. A high turbulence level of 16% with an integral length scale of 3.6%P was generated using inlet turbulence grid to reproduce the typical turbulence conditions in real turbine. Low temperature air was used to simulate the typical coolant-to-mainstream condition by controlling two parameters of the upstream coolant injection flow: mass flowrate to determine the coolant-to-mainstream blowing ratio (BR = 2.5, 3.5), and gas temperature to determine the density ratio (DR = 1.2). To highlight the interactions between the upstream coolant flow and the passage secondary flow combined with the influence on the endwall heat transfer and cooling performance, a comparison of CFD predictions with experimental results was performed by solving steady-state Reynolds-averaged Navier–Stokes (RANS) using the commercial CFD solver ansys fluent V.15. A detailed numerical method validation was performed for four different Reynolds-averaged turbulence models. The realizable κ−ε model was validated to be suitable to obtain reliable numerical solution. The influences of a wide range of coolant-to-mainstream blowing ratios (BR = 1.0, 1.5, 1.9, 2.5, 3.0, 3.5) were numerically studied. Complex interactions between coolant injections and secondary flows in vane passage were presented and discussed. An optimal value of the blowing ratio for the present upstream discrete film hole is also suggested based on the current study. Results indicate that for lower values of BR, the endwall coolant coverage from the upstream double-row discrete holes is strongly controlled by the passage secondary flow, thus the cooling effectiveness is very poor. As the BR increases, the strong secondary flow in vane passage can be suppressed by the coolant injections and begin to be almost eliminated when BR increases to a critical value (BR = 2.5–3.0). Beyond the critical BR, most of the injected coolant begins to lift off from the endwall and penetrate significantly into the mainstream flow, yielding inefficient endwall cooling performance.

Corner stall control in linear compressor cascade by blended blade and endwall technique based on large eddy simulation

Under the influence of a strong adverse pressure gradient, secondary flow, and other factors, compressor cascades are prone to corner separation and even to corner stall, which seriously affects aerodynamic performance. In this paper, large eddy simulation is used to investigate the effects and mechanisms of corner stall controlled by the blended blade and end wall (BBEW) technique. Based on this technique, three BBEW control schemes with different chord-direction positions of the maximum BBEW width are designed for the suction side root of a modified NACA (National Advisory Committee for Aeronautics) 65 blade. The influence of the chord-direction position of the maximum BBEW width on control corner stall and the differences of physical mechanisms are deeply explored. The numerical results show that the BBEW technique can improve the flow field structure and aerodynamic performance of a compressor cascade under corner stall conditions to a certain extent. When the maximum BBEW width is located near the leading edge, it provides the most significant reduction in the spanwise height of corner separation and effectively weakens the intersection of boundary layers, so that the boundary layer losses are reduced by 6.27%, and the overall performance is improved. These effects can be attributed to the axial and spanwise forces generated near the maximum BBEW width, with the former increasing the kinetic energy of the surrounding fluid, while the latter transports low-energy fluid upward to reduce accumulation on the end wall. In addition, the increased dihedral angle weakens the intersection of boundary layers and restrains the development of the corner vortex, which is also one of the underlying physical mechanisms. When the maximum BBEW width is located in the middle of the chord, it most effectively delays the corner stall. When it is located near the trailing edge, it is most effective at controlling the development of corner separation, reducing the accumulation of low-energy fluid in the three-dimensional corner region, and reducing corner separation losses by 4.73%. The effect of the increased dihedral angle in weakening the intersection of boundary layers and the corner vortex is the main reason why these two design schemes can improve the aerodynamic performance of the compressor cascade.

Characterization of the hydrodynamics within a toroid wear tester

AbstractThe toroid wear tester (TWT) is a lab‐scale device used for the assessment of slurry erosion in pipelines. Historically, its application has been limited to the relative ranking of material performance under different slurry flow conditions; however, recent studies have indicated that TWT tests could be predictive and directly applied to slurry pipeline design—provided that the flow inside a TWT is better characterized. In the present study, air‐liquid multiphase flow inside the TWT was investigated. Torque measurements were taken to characterize friction loss for different air‐liquid combinations. A visualization experiment was also conducted to evaluate flow patterns within the TWT. In the experiment, the displacements of spherical glass beads were used to estimate velocity vector fields for different TWT rotational speeds. A computational fluid dynamics (CFD) analysis was also conducted to complement the experimental measurements. A 3D transient analysis using the volume of fluid (VOF) approach was used to model the system. The simulation results agreed closely with the experimental findings. Furthermore, the simulations revealed that strong secondary flows (back flow, rotation) exist in the TWT. These type of flows do not occur in horizontal pipelines. Therefore, to use the TWT as a tool for slurry pipeline wear assessment, the differences in the flow field between the two systems must be properly quantified.

Numerical analysis of two-phase ferrofluid forced convection in an annulus subjected to magnetic sources

This work presents a numerical analysis of heat transfer and flow characteristics of a ferrofluid inside an annulus. The ferrofluid flow is subjected to multiple magnetic fields emanating from current-carrying wires. The inner tube of the annulus is heated uniformly while the outer tube is insulated. Two-phase modeling is conducted by incorporating Brownian, thermophoretic, and magnetophoretic effects. The dependence of ferrofluid viscosity and thermal conductivity on the magnetic field intensity and temperature is considered. The finite volume approach is applied to solve the governing equations. The influences of magnetic number, relative angular position, the number of magnetic sources, and also radius ratio of the annulus on the augmentation of heat transfer and pressure losses are examined. Numerical findings show that the applied magnetic fields induce a strong secondary flow whose magnitude may be several times higher than that of the inlet velocity. In the case of two current-carrying wires, the rate of heat transfer is enhanced by increasing the relative angular distance between the two magnetic sources and shows a maximum at Δθ=180°. It is found that there exists an optimum number of magnetic fields that maximize the rate of heat transfer. Additionally, the average Nusselt number declines as the radius ratio rises.

Unsteady flows of a highly loaded turbine blade with flat endwall and contoured endwall

Strong secondary flow results in substantial aerodynamic loss for highly-loaded turbine. Accurate prediction of the complicated flow structures proposes challenges to the widely used Reynolds Average Navier-Stokes (RANS) approach. This work employs the hybrid RANS/Large Eddy Simulation (LES) method to study the unsteady flows for a highly-loaded turbine blade, with both flat endwall and optimized contoured endwall. Evolution of the unsteady flows in the endwall region is analyzed, with emphasis on the loss generation mechanism. Results show that for the flat endwall, the horseshoe vortex system is highly unsteady and is a significant source of unsteadiness in both the passage and the wake region. It contributes to the unsteady passage vortex, also the earlier breakdown of the trailing edge shedding vortex. The Probability Density Function (PDF) histogram of velocity in the wake region is bimodal, implying the perturbations from two mechanisms. For the contoured endwall, the unsteady evolution of the horseshoe vortex is blocked, which results in significantly reduced unsteadiness, also the merge between the horseshoe vortex with the passage vortex is prevented. Effect of the flow unsteadiness on the loss generation is assessed based on the entropy generation rates contributed by the time-averaged flow and the fluctuations. The effect of unsteadiness is two-fold: unsteady perturbations trigger the vortex breakdown into small-scale structures and thus weakened wake velocity deficit and loss generation; however, in both the passage and the wake region the entropy generation by the fluctuations are remarkable. For the contoured endwall, due to the reduced flow unsteadiness, loss generation contributed by the fluctuations are much smaller compared to the flat endwall. The results highlight the importance of including the loss generation by the fluctuations, also a possible mechanism to reduce the secondary loss by attenuating the flow unsteadiness with the contoured endwall.

Investigations on Predictions and Characteristics of Flow Field in the Pipelines of Chillers for Measured Locations of Ultrasonic Flowmeters by CFD Approach

The flow velocity profiles in most of the central air-conditioning pipelines are, in general, not fully developed flow and difficult to obtain the accurate flow rates by flowmeters, which are used for measuring average velocity. Especially for being at the outlet of an elbow, the accuracy of flow rate by measurement is quite low. Therefore, there are some limitations for measurements of flow rate and velocity profile by the present flow measuring technologies. The objective of this study was to establish an approach on accurate predictions of velocity profiles at different measured locations of central air-conditioning pipelines for nonuniform flow measurements by simulations of computational Fluid Dynamics (CFD). All the velocity profiles will integrate as a database for predictions by neural network algorithm for smart measurement further. In the present work initially, international experiments were employed to validate the accuracy of CFD approach. The calculations were carried out by different turbulence models. The results compared with the experimental data by Realizable [Formula: see text]-[Formula: see text] turbulence model with less computing resources have great agreements. Realizable [Formula: see text]-[Formula: see text] turbulence model was, therefore, determined for the predictions of central air-conditioning pipeline. According to various pipings and pipe sizes, the results for three cases show that the velocity profiles in the pipelines would not be symmetrical and has strong secondary flow. Therefore, all of the flow profiles would be integrated and analyzed as a database and assist to get accurately the measured locations of ultrasonic flowmeters. Further, this database will be combined with algorithm of artificial neural network for smart predictions.

Experimental Study of the Use of Tracing Particles for Interface Tracking in Primary Cementing in an Eccentric Hele–Shaw Cell

We present the results of the displacement flows of different Newtonian and Herschel–Bulkley non-Newtonian fluids in a new-developed eccentric Hele–Shaw cell with dynamic similarly to real field wellbore annulus during primary cementing. The possibility of tracking the interface between the fluids using particles with intermediate or neutral buoyancy is studied. The behaviors and movements of particles with different sizes and densities against the primary vertical flow and strong secondary azimuthal flow in the eccentric Hele–Shaw cell are investigated. The effects of fluid rheology and pumping flow rate on the efficiency of displacement and tracing particles are examined. Moreover, the behavior of pressure gradients in the cell is described and analyzed. Successful results of tracing the interface using particles give us this opportunity to carry out a primary cementing with high quality for the cases that the risk of leakage is high, e.g., primary cementing in wells penetrating a CO2 storage reservoir.

Kinematic Measurements of Novel Chaotic Micromixers to Enhance Mixing Performances at Low Reynolds Numbers: Comparative Study.

In this work, a comparative investigation of chaotic flow behavior inside multi-layer crossing channels was numerically carried out to select suitable micromixers. New micromixers were proposed and compared with an efficient passive mixer called a Two-Layer Crossing Channel Micromixer (TLCCM), which was investigated recently. The computational evaluation was a concern to the mixing enhancement and kinematic measurements, such as vorticity, deformation, stretching, and folding rates for various low Reynolds number regimes. The 3D continuity, momentum, and species transport equations were solved by a Fluent ANSYS CFD code. For various cases of fluid regimes (0.1 to 25 values of Reynolds number), the new configuration displayed a mixing enhancement of 40%–60% relative to that obtained in the older TLCCM in terms of kinematic measurement, which was studied recently. The results revealed that all proposed micromixers have a strong secondary flow, which significantly enhances the fluid kinematic performances at low Reynolds numbers. The visualization of mass fraction and path-lines presents that the TLCCM configuration is inefficient at low Reynolds numbers, while the new designs exhibit rapid mixing with lower pressure losses. Thus, it can be used to enhance the homogenization in several microfluidic systems.

Efficient design of heat exchange for CFB reactors in CO2 capture system regarding geometry-induced secondary flow

CO2 capture technology using temperature-swing adsorption faces many obstacles for commercialization. Circulating fluidized bed systems have high capture performance, but an energy-efficient design is essential to reduce the CO2 capture cost. In this study, thermal-fluid characteristics of circulating fluidized bed with two-phase flow are analyzed, and thermal design is implemented. First, a laboratory-scale circulating fluidized bed system was used to investigate the relationship between hydrodynamics and heat transfer in experiments and numerical simulations. Numerical method predicted well the pressure fluctuations and local bed-to-wall heat transfer. Particle behaviors affected greatly the heat transfer. Accordingly, to control solid particle flow, the effect of reactor geometry on hydrodynamics and heat transfer was analyzed. Compared with the conventional circular reactor, the rectangular reactor had a secondary flow of solid particles in the horizontal section. Flow toward the narrow wall, and rotational flow near the corners, were identified. Intensity of the secondary flow depended on the aspect ratio. It was firstly reported that the geometry-induced secondary flow affected significantly heat transfer. Due to the strong secondary flow in the rectangular reactor, the local heat transfer was more than doubled. Ultimately, thermal design was carried out by analyzing the minimum temperature difference (MTD) according to the reactor geometry. The rectangular reactor showed an MTD of 67% compared to the circular reactor and 45% compared to the square reactor. Because MTD decreased and the coolant amount increased simultaneous with increasing aspect ratio, the rectangular reactor with an aspect ratio of 4:1 was the most energy-efficient design. Finally, through thermal design, the pilot-scale rectangular reactor is designed and under-constructed in order to evaluate the CO2 capture system performance and the potential for commercialization.

Experimental and numerical investigation of a supersonic inlet with double S-bend diffuser

Design of a supersonic inlet with double S-bend diffuser was developed. Numerical simulation and wind tunnel experiment were carried out to investigate the aerodynamic performance and variable geometric rules of the inlet. The result indicates that the variable geometry scheme adopted solves the contradiction between starting performance at low Mach number and aerodynamic performance at high Mach number. The inlet works normally and stably over a wide speed range. At design point, the total pressure recovery coefficient reaches 0.47. In addition, two different kinds of inlets with double S-bend diffuser and single S-bend diffuser were studied. Compared with the double S-bend diffuser, the total pressure recovery coefficient of the single S-bend diffuser is higher at low Mach number (Ma0 < 3) and lower at high Mach number (Ma0 > 3). With the increase of backpressure, shock train mainly moves upstream along the low-energy flow region in the diffuser. For the double S-bend diffuser, shock train will first move along the lower corner and then along the upper corner. For the single S-bend diffuser, it will only move along the upper corner. The strong secondary flow of the double S-bend is the main reason for the above phenomenon.

Thermal performance enhancement of a double-tube heat exchanger with novel twisted annulus formed by counter-twisted oval tubes

A novel twisted annulus between two counter-twisted oval tubes is proposed for a double-tube heat exchanger. The oval tubes of the annuli have same twist pitch, but twist with opposite twisting directions. The thermohydraulic performance of the annuli with different aspect ratios and twist ratios is numerically presented. The results indicate that strong secondary flow is generated in the twisted annulus, which can significantly promote the heat transfer. The maximum Nu and f of the twisted annuli are separately 157% and 118% larger than those of the corresponding straight annuli. The largest value of the thermal performance factor is 1.98 in the studied range of geometrical parameters. Correlations of Nu and f as a function of Re, twist ratio and aspect ratio are proposed with the deviations within ±10% and ±8%, respectively.

Sound radiation of the exhaust gas turbocharger as a function of the compressor inflow

The use of exhaust gas turbochargers in modern engine concepts is essential to achieve high efficiencies, low fuel consumption, and low emissions. However, the high rotational speed, a wide range of compression ratios, and dynamic acceleration and deceleration processes cause both tonal and broadband sound radiation. Due to packaging constraints, the intake cycle is often characterized by deflections and cross-section jumps. That leads to a strong secondary flow at the inflow of the compressor. Therefore, in this study, we intensively investigated the influence of disturbed inflow conditions on the sound radiation of the exhaust gas turbocharger. As a result, we found that the flow caused by a 105∘-bend in front of the compressor leads to an increase in broadband flow noise up to 5.5dBA. The decisive factor here is the amount of pre-whirl at the outer radius of the pipe. A high velocity gradient additionally shifts the surge line towards lower flow coefficients and mass flows, respectively. That indirectly reduces the sound radiation due to the greater distance of the operating points to the surge line. However, pre-whirl can counteract this effect. The surge line shifts to larger mass flows due to the decrease of the relative flow angle. In contrast, low turbulence levels and homogeneous compressor inflow lead to reduced flow separation and thus lower broadband sound radiation. The reduction of the secondary flow in the intake of the compressor, e.g. due to pre-guidance devices, therefore represents a promising way of reducing the noise emission of the exhaust gas turbocharger in a passenger car.

Numerical Investigation on the Secondary Flow Control by Using Splitters at Different Positions with Respect to the Main Blade

In turbomachinery, strong secondary flow can produce significant losses of total pressure near the endwall and reduce the efficiency of the considered turbomachine. In this study, splitters located at different positions with respect to the main blade have been used to reduce such losses and improve the efficiency of the outlet guide vane (OGV). Three different relative positions have been considered assuming a NACA 65-010 profile for both the main blade and the splitter. The numerical results indicate that splitters can effectively reduce the total pressure loss by suppressing the secondary flow around the main blade, but the splitters themselves also produce flow losses, which are caused by flow separation effects.

Numerical Investigation of Three-Dimensional and Vortical Flow Phenomena to Enhance the Power Performance of a Wind Turbine Blade

The performance of a wind turbine generator (WTG) is highly dependent on the interaction of a rotor blade with complex fluid behaviors, especially the induced vortex structure. In this paper, vortical flows around a blade were first investigated by the unsteady Reynolds averaged Navier–Stokes (RANS) simulation with shear stress transport (SST) turbulence model. It showed that the vortical flows were strongly formed at the blade tip due to the 3D behavior of the boundary layers dominated by pressure gradient. The strong secondary flow was also formed at the near hub due to the Coriolis force and the centrifugal force. At the interacting region of the rotating blade with the tower, the power production was reduced by 22.1% due to the high-pressure fluctuation of the 3P frequency. Based on the close investigation, methods for enhancing the power performance of a WTG were explored, which included the optimization of winglet and ogee design for the blade tip and optimal layout of the nacelle anemometer. The optimized winglet achieved the increase of aerodynamic performance with 0.54%, and the optimal location of the nacelle anemometer was found with a low-turbulence intensity level of 0.003 normalized by the rotor tip speed. The results showed that the traditional anemometer needs to consider the intrinsic flow angle of 11.43° to avoid the loss of aerodynamic performance caused from yaw error.

Numerical investigation of nanoparticle deposition location and pattern on a sharp-bent tube wall

The characteristics of fluid flow on a sharp-bent tube under various conditions were analyzed. Numerical simulations for analyzing the particle deposition locations and patterns on a sharp-bent tube were conducted by using the modified single-particle tracking analysis based on aerosol mass flow rate. Through the numerical calculation, we showed that after the bending point in a sharp-bent tube, the faster axial velocity occurred near the outer wall, and the boundary layer at high Reynolds number became thinner. Furthermore, the faster radial velocity near the tube wall was observed at less developed-flow region at high Reynolds number owing to the stronger secondary flow. The nanoparticle deposition locations and patterns were systematically examined in various viewpoints including cumulative number of deposited particles, local deposition enhancement factor, and particle deposition pattern according to azimuthal angles. We found that most of the nanoparticles were deposited on the outer wall right after the bending point owing to outward-sloping flow. Moreover, the difference in relative deposition efficiency along the azimuthal angles at each section in the sharp-bent tube was reduced as Reynolds number increased. This is because the nanoparticles near the wall were well mixed due to the strong secondary flow at high Reynolds number.