Intensity Of Secondary Flow Research Articles

Numerical investigation of bio-inspired mixing enhancement for enzymatic hydrolysis

High-solids enzymatic hydrolysis is a promising technology for biochemical conversion of lignocellulosic biomass. However, it may suffer from low efficiency in stirred-tank reactors due to poor mixing degree and enzyme deactivation by excessive shear rate. Inspired by the efficient mixing of viscous chyme and enzyme during intestinal motility, a biomimetic model with an enzyme secretion boundary was first proposed to explore the mixing enhancement mechanism. The dimensionless number Sem was established to characterize the secondary flow intensity. The results showed that increasing the segmentation amplitude to 66.7% improved Sem to 9.5 and the mixing level to 38.5%. Extension of the segmentation period resulted in the reduction of Sem, thus decreasing the mixing enhancement. The time-averaged mixing level was increased by 76.0% compared with the static tube at a substrate viscosity of 5.0 Pa·s. Furthermore, the shear strain rate was lower than 220.4 s−1, which was conducive to maintaining enzyme activity.

A spanwise loss model for axial compressor stator based on machine learning

In the early stage of aircraft engine design, the through-flow method is an important tool for designers. The accuracy of the through-flow method depends heavily on the accuracy of the loss model. However, most existing models cannot (or cannot well) provide the spanwise loss distribution. To construct an effective spanwise loss model, both turbomachinery knowledge and machine learning skills were used in this paper. A large number of numerical simulations were carried out to build a database containing more than 1000 compressor cascade numerical samples. Secondary flow intensity was introduced as the independent variable to carry out feature engineering. A model containing a selector based on support vector machine regression and estimators based on K-nearest neighbor regression was constructed. Numerical test set and design data of two former high-pressure core compressors were used for validation. Results suggest that the spanwise loss model show good consistency with both numerical test set and data of two former compressors. It can reflect the influence of secondary flow and can also predict both value and trend of total pressure loss coefficient well, with mean absolute error general around or less than 1% and R2 (coefficient of determination) more than 0.8 on the test set. Especially when dealing with loss coefficient at mid-span position, the model shows even better performance, with R2 over 0.97 on the test set. And the selector of the model can well classify the samples, predict the intensity of secondary flow and help estimators to capture the phenomenon that end-wall secondary flow extends to the mid-span.

Modeling and Simulation Analysis on Mixing Characteristics of Two-Phase Flow Around Spacer Grid

The spacer grid has a significant impact on the thermal-hydraulic characteristics of the rod bundle channel, which directly determines the possibility of a boiling crisis. The multi-phase flow model coupling boiling model is proposed to acquire the secondary flow and void fraction for subcooled flow boiling in the fuel assembly. Compared with the experimental data, the RNG k–ε turbulence model is selected in the current research. In addition, the thermal-hydraulic parameters of subcooled boiling flow in the 5 × 5 rod bundle with a spacer grid are studied focusing on the influence of different arrangements of mixing vanes. It is found that the distribution of the vapor phase is greatly influenced by the intensity and flow direction of secondary flow. In addition, the thermal–hydraulic characteristics in the sub-channels and around the fuel rods are investigated, which demonstrates that uniform crossflow makes vapor harder to accumulate around the fuel rods. Furthermore, the mixing characteristics of different types of spacer grids are also discussed in detail.

Flow and thermal characteristics produced by a curved rectangular winglet vortex generator in a channel

Three-dimensional numerical computations are performed to investigate the performance of curved winglets mounted on a rectangular channel. The concave and convex shapes of curved rectangular winglet vortex generators (RWVGs) are named according to flow facing surface. Curvature of winglet mainly depends on arc angle, radius of curvature, arc length and chord length. Present study investigates the influence of arc angle variation of curved RWVG on flow and thermal characteristics for fixed chord length. Arc length and radius of curvature of curved RWVG vary according to arc angle. With the help of streaklines plots and iso-Q surfaces, flow behavior around the curved RWVG has been investigated. Heat transfer enhancement of curved RWVGs has been examined by using the dimensionless parameters surface-averaged Nusselt number, while pressure loss is estimated by friction factor. The overall thermohydraulic performance of curved RWVGs is inspected by thermal performance factor. Investigations of secondary flow intensity are carried out to understand its impact on heat transfer mechanism. From the investigation of secondary flow, it is observed that secondary flow provides a supplement to the traditional method of analyzing heat transfer performance.

The flow mechanism of the shock structure and secondary flow control in transonic centrifugal compressors with leading edge sweep

Limitations still exist in the research on the effects of leading edge sweep on transonic centrifugal compressors. The lack of understanding of this mechanism also leads to confusion regarding the magnitudes of the performance changes that occur due to the use of leading edge sweep. According to a detailed numerical simulation verified by experiments on two different compressors, the effect and flow mechanism of leading edge sweep on transonic centrifugal compressors were investigated in detail to alleviate the confusion as clearly as possible. The conclusions show that leading edge sweep has different impacts on shock waves at different positions; a forward sweep leading edge can weaken the strength of the shock wave in front of the leading edge, while a backward sweep leading edge can weaken the strength of the passage shock wave that is swallowed in the blade passage. The improved compressor performance attributed to leading edge sweep is due to the weakening of the shock waves and the interaction between the shock waves and the secondary flow of the inducer tip. Furthermore, the intensity of the inducer tip secondary flow influences the potential for improved performance induced by using sweep leading edges in transonic centrifugal compressors. This study provides a valuable reference for applying leading edge sweep to existing transonic centrifugal compressors or future advanced centrifugal compressor designs.

Flow Non-Uniformity and Secondary Flow Characteristics Within a Serpentine Cooling Channel of a Realistic Gas Turbine Blade

Abstract Unlike the ideal conditions considered in most previous studies, the actual cooling flow passage inside gas turbine blades is extremely complex. This complexity is due to the geometrical restrictions resulting from the external cooling holes and blade shape, which change the secondary flow and flow non-uniformity of the internal cooling flow. This study conducted an experimental and numerical analysis to characterize the secondary flow and flow non-uniformity in a realistic internal cooling serpentine passage. Magnetic resonance velocimetry was utilized to measure the average three-dimensional–three-components of the mean velocity. By integrating the flow field, parameters indicating the flow non-uniformity and secondary flow strength were obtained. Reynolds-averaged Navier–Stokes simulations were also conducted, and the Reynolds stress transport model showed relatively good performance when predicting the separation bubble in the U-bend. The secondary flow intensity exponentially decreases after the U-bend, but the rib turbulators maintain the secondary flow at a certain level. Additionally, the high-velocity regions in the inlet zone and beyond the separation bubble create significant flow non-uniformity and inherent shear. At the same time, the turbulence intensity becomes strong at the low-velocity region, which is key for heat transfer enhancement. Therefore, high flow non-uniformity has the potential to enhance heat transfer.

Study on dominant heat transfer mechanism in vertical smooth/finned-tube thermal energy storage during charging process

• Heat transfer mechanism of heat conduction is dominant in smooth-tube TES. • The heat transfer in finned-tube TES is dominated by secondary flow. • Heat conduction enhancement rate was defined to characterize the heat conduction intensity. • Heat conduction enhancement rate increases with the increase of the number of fin. • Aluminum finned TES obtains the best thermal storage efficiency. Thermal energy storage (TES) is an indispensable part of solar energy utilization system. This paper intends to explore the role of heat conduction, natural convection and secondary flow on the charging performance of phase change material in vertical smooth/finned-tube TES respectively. It was found that heat conduction is dominant in smooth-tube TES. The role of natural convection is to cause non-uniformity of melting rate of the lower and upper part. Meanwhile, secondary flow is dominant in finned-tube TES due to the generation of vortices between adjacent fins. Fin material has little effect on the melting characteristic of phase change material when fin pitch is larger than 40 mm in this study. Therefore, nonmetallic fin and cheap metallic fin could be used in finned-tube TES to increase thermal storage density and reduce cost of investment. Compared to conduction model, the total melting time was reduced by 9.7% and 34.2% in smooth-tube TES and aluminum finned-tube TES when convection model is considered in the computation. Besides, the heat conduction intensity and secondary flow intensity were explored in aluminum finned-tube TES. The heat conduction enhancement rate φ was defined to characterize the heat conduction intensity. With the fin pitch decreasing from 40 mm to 8 mm, the heat conduction enhancement rate increases from 15.2% to 39.6%, indicating that heat conduction plays a crucial role in the finned-tube TES. The aluminum finned TES exhibit the best thermal storage characteristic as a result of the best heat transfer enhancement and smaller density.

Blade redesign based on secondary flow suppression to improve energy efficiency of a centrifugal pump

This paper conducts a systematic study to address the problems of high flow loss and low energy efficiency of centrifugal pumps caused by the development of secondary flow within the impeller. Based on the forces balance in the direction perpendicular to the streamline, theoretical calculations are drawn to redesign blade thickness for a 5-blade centrifugal impeller to suppress the secondary flow. The correlations between the development of internal secondary flow within the impeller and energy efficiency of centrifugal pump under full flow rate conditions are illustrated by numerical simulations validated by experimental tests. Secondary flow coefficient and entropy production rate (EPR) are introduced and extracted to quantitative analysis the secondary flow level and energy loss inside the impeller. Results indicate that the blade redesign methods proposed here can efficiently inhibit the development of secondary flow and improve the energy efficiency. Moreover, the secondary flow coefficient introduced in this paper can quantitatively reflect the intensity of secondary flow under various flow rates of different impellers. Combining with the entropy production analysis of impeller, the consistent change trend of total secondary flow coefficient and entropy production reveals that the improvement of pump energy efficiency benefits from the reduction of turbulence EPR which results from the suppression of internal secondary flow.

The Effects of Axisymmetric Convergent Contouring and Blowing Ratio on Endwall Film Cooling and Vane Pressure Side Surface Phantom Cooling Performance

Abstract To reduce the intensity of endwall secondary flow, the axisymmetric convergent contoured endwall is commonly designed in the first nozzle guide vane (NGV) passage of the real gas turbine engines. This endwall contouring can obviously alter flow field near endwall and affect the coolant flow through the upstream double-row discrete film holes. This leads to a significant influence on the endwall film cooling performance, vane surface phantom cooling, and vane passage aerodynamic performance. In this paper, a detailed numerical investigation on the endwall film cooling and vane pressure side surface phantom cooling was performed, at the simulated realistic gas turbine operating conditions (high inlet freestream turbulence level of 16%, exit Mach number of 0.85, and exit Reynolds number of 1.7 × 106). Based on a double coolant temperature model, a novel numerical method for the predictions of adiabatic wall film cooling effectiveness was proposed. This numerical method was validated by comparing the predicted results with experimental data of endwall Nusselt number, endwall film cooling effectiveness, and flow visualization near endwall. The results indicate that the present numerical method can accurately predict endwall thermal load distributions, endwall film cooling distributions, and vane surface phantom cooling distributions. The endwall heat transfer coefficient, endwall film cooling effectiveness, phantom cooling effectiveness of the vane pressure side surface, and total pressure loss coefficients (TPLC) were predicted and compared for two endwall contouring shapes (flat endwall and axisymmetric convergent contoured endwall) at three different blowing ratios (low blowing ratio of BR = 1.0, design blowing ratio of BR = 2.5, and high blowing ratio of BR = 3.5) with a constant density ratio of DR = 1.2, based on the present novel numerical method. Results show that the axisymmetric convergent endwall contouring leads to a slight enhancement (maximum enhancement level less than 20%) of endwall heat transfer in the entire vane passage (0 < x < 0.65Cx). The axisymmetric convergent endwall contouring has a significantly desired effect on endwall film cooling performance (maximum enhancement level of 67%), phantom cooling performance of the vane pressure side surface (maximum increase level approximately 100%), and aerodynamic loss (maximum reduction level of 1.45%) for all blowing ratio cases, but the benefit enhancement level is obviously affected by the blowing ratio values. This suggests that the optimum of endwall contouring shapes is an effective technical way to improve endwall film cooling performance and decrease the depletion of coolant; the coupled effects of the appropriate axisymmetric convergent endwall contouring and the optimum blowing ratio should be considered in the design process of advance endwall cooling schemes.

Experimental investigation of 90° intake flow patterns with and without submerged vanes under sediment feeding conditions

In this study, two experiments were conducted in a 90° water intake to study 3D flow patterns and sediment distribution using submerged vanes under sediment feeding and live-bed conditions. One column three vanes were installed at a 20° angle maintaining for a water discharge ratio of qr ≈ 0.1. Three-dimensional mean and turbulent velocity components of flow in a 90° channel intake were measured using acoustic Doppler velocimetry (ADV). Flow characteristics of the intake structure area with no vanes were compared with these conditions. Results showed that three vanes with a single column reduced the amount of sediment by 20% during intake diversion. In the downstream corner of the intake, high velocities were measured where scouring occurred. The vanes affected the intensity of secondary flow, turbulence energy, flow separation, and moved sediment deposition downstream of the main channel.

Flow and heat transfer analysis of lead–bismuth eutectic flowing in a tube under rolling conditions

The investigation of flow and heat transfer of lead–bismuth eutectic (LBE) under rolling conditions is vital to the application of LBE cooled reactor in offshore engineering. In this paper, mature numerical method for modelling low Prandtl number liquid metal is used for LBE flow in a vertical tube under rolling conditions. Reynolds stress turbulent model is chosen to consider the complex secondary flow caused by additional force. It is found that the transverse additional force is the main reason accounting for the enhancement of heat transfer and secondary flow. The transient maximum heat transfer ability can be enlarged by 18% under condition of rolling angle of 30° and period of 8 s. And 10 times transverse additional force caused by rolling angle of 30° and period of 8 s is enough to change the flow resistance characteristic of LBE. Comparisons with water coolant indicate that the intensity of radial secondary flow play an important role in determining the heat transfer characteristic of fluid under rolling conditions. The high density and low Prandtl number also make the features of LBE under rolling conditions different from those of water. The empirical correlations used in system code now could not predict the flow and heat transfer of LBE under rolling conditions. Special attention should be paid to safety design criteria of the off-shore LBE cooled reactor. This paper may contribute to the thermal–hydraulic design of off-shore liquid metal cooled reactors.

Performance comparison among the variants of curved serpentine coil

In the present work, two variants of the novel curved serpentine coil formed by relaxing the switching angle at the junctions are explored and compared with the original design for the same mean radius Rm of concentric tubes. With α as the semi-cone angle and θ as the subtended angle of concentric tubes, the general notation given to different variants of the curved serpentine coil is CS-α-θ. The three variants are named as a cylindrical curved serpentine coil (α = 0°), conical curved serpentine coil (0° < α < 90°), and spiral curved serpentine coil (α = 90°). The fluid experiences a switching angle of 90° − α and 90° + α at the entrance and exit of every U-bend, respectively. The laminar flow of water in CS-α-θ coils (45° ≤ θ ≤ 270°, 0° ≤ α ≤ 90°) is simulated using ANSYS FLUENT version 20.2 for the range 500 ≤ Re ≤ 2000. The length-averaged Nu and f are found to decrease with an increase in either α or θ for the same mean radius Rm of concentric tubes. Secondary flow intensity is quantified using the parameter Se and is correlated with the flow and geometric parameters. Generalized correlations for predicting the average Nusselt number and friction factor for CS-α-θ coils are expressed as the sum of corresponding straight tube values and as a function of Se with a maximum deviation of ±8.5% and ±7%, respectively.

Hydrodynamic Characteristics of Flow in a Strongly Curved Channel with Gravel Beds

This study experimentally and numerically investigated the hydrodynamic characteristics of a 180° curved open channel over rough bed under the condition of constant downstream water depth. Three different sizes of bed particles (the small, middle and big cases based upon the grain size diameter D50) were selected for flume tests. Three-dimensional instantaneous velocities obtained by the acoustic Doppler velocimeter (ADV) were used to analyze hydrodynamic characteristics. Additionally, the Renormalization-Group (RNG) turbulence model was employed for numerical simulations. Experimental results show that rough bed strengthens turbulence and increases turbulent kinetic energy along curved channels. The power spectra of the longitudinal velocity fluctuation satisfy the classic Kolmogorov −5/3 law in the inertial subrange, and the existence of rough bed shortens the inertial subrange and causes the flow reach the viscous dissipation range in advance. The contributions of sweeps and ejections are more important than those of the outward and inward interactions over a rough bed for the middle case. Flow-3D was adopted to simulate flow patterns on two rough bed settings with same surface roughness (skin drag) but different bed shapes (form drag): one is bed covered with thick bottom sediment layers along the curved part of the flume (the big case) as the experimental condition, and the other one is uniform bed along the entire flume (called the big case_flat only for simulations). Numerical simulations reveal that the secondary flow is confined to the near-bed area and the intensity of secondary flow is improved for both rough bed cases, possibly causing more serious bed erosion along a curved channel. In addition, the thick bottom sediments (the big case), i.e., larger form drag, can enhance turbulence strength near bed regions, enlarge the transverse range of secondary flow, and delay the shifting of the core region of maximum longitudinal velocity towards the concave bank.

A numerical investigation on the heat transfer and turbulence production characteristics induced by a swirl spacer in a single-tube geometry under single-phase flow condition

Heat transfer in the rod bundle is augmented by the mixing vanes on the spacer grid. We conducted a computational fluid dynamics (CFD) simulation with three isotropic turbulence models – standard k–ε, realizable k–ε, and SST k–ω models – to investigate the relationship between heat transfer and turbulence behaviors downstream a simulant spacer (with four vanes) in a single tube under single-phase flow conditions. Quantitatively, the predicted heat transfer coefficient (HTC), secondary flow intensity, and turbulence intensity with the SST k–ω model displayed a better agreement (than the other isotropic models) with the experimental data in previous studies. Moreover, the turbulence production was localized in the near-spacer region (z/D < 10, where D is the inner diameter), which corresponds with the HTC augmentation region. These results indicate that examining the turbulence production when discussing the HTC augmentation downstream the spacer is essential.

Coriolis and buoyancy effects on heat transfer in viewpoint of field synergy principle and secondary flow intensity for maximization of internal cooling

The present investigation emphases on rotation effects on internal cooling of gas turbine blades both numerically and experimentally. The primary motivation behind this work is to investigate the possibility of heat transfer enhancement by dean vortices generated by Coriolis force and U-bend with developing turbulent in the view point of the field synergy principle and secondary flow intensity analysis. A two-passage internal cooling channel model with a 180° U-turn at the hub section is used in the analysis. The flow is radially outward at the first passage of the square channel and then it will be inward at the second passage. The study covers a Reynolds number (Re) of 10,000, Rotation number (Ro) in the range of 0–0.25, and Density Ratios (DR) at the inlet between 0.1–1.5. The numerical results are compared to experimental data from a rotating facility. Results obtained with the basic RANS SST k-ω model are assessed completely as well. A field synergy principle analysis is consistent with the numerical results too. The results state that the secondary flows due to rotation can considerably improve the synergy between the velocity and temperature gradients up to 20%, which is the most fundamental reason why the rotation can enhance the heat transfer. In addition, the Reynolds number and centrifugal buoyancy variations are found to have no remarkable impact on increasing the synergy angle. Moreover, vortices induced by Rotation number and amplified by Reynolds number increase considerable secondary flow intensity which is exactly in compliance with Nusselt number enhancement.

Effect of visco-plastic and shear-thickening/thinning characteristics on non-Newtonian flow through a pipe bend

This study investigates the influence of the rheological parameters on the unyielded zone, pressure drop, and secondary flow pattern of non-Newtonian fluid like fresh cement mortar through a pipe bend with different curvatures. The regularized Herschel–Bulkley model is employed in the framework of lattice Boltzmann method to model the effects of the visco-plastic and shear-thickening/thinning characteristics with variations on the yielding stress σ0 and the power-law index n. The sharper curvature, higher power-law index contributes to a smaller and more asymmetric unyielded zone and even vanishes for curvature radius Rc=1D and n = 1.4, as the width and distribution of plug region are governed by the comparison between yielding stress and shear stress. The increased yielding stress and power-law index lead to an increase in the total pressure drop and additional pressure loss; however, their variations with respect to the curvature radius display an opposite trend. The intensity of the helical secondary flow in the elbow, primarily governed by the competition between the centrifugal and viscous force, is reduced to about one quarter when σ0 and n increase from 0 Pa and 0.6 to 50 Pa and 1.4.

Convective heat transfer enhancement mechanisms in circular tube inserted with a type of twined coil

Numerical method is used to investigate convective heat transfer enhancement mechanisms in a tube with a new kind of twined coil insert. The numerical results are examined by the experiments specially designed. The heat transfer performance of the tube with the twined coil insert is evaluated in thermal performance factor JF at identical mass flow rate. The heat transfer enhancement mechanisms of the twined coil insert are discussed. It is found that the twined coil insert can make fluid flow be complicated three-dimensional mixed flow, and increase the intensity of secondary flow greatly. These factors can enhance mixing of fluids having different temperature, and then the heat transfer performance in the tube is enhanced. Under the same working conditions, the heat transfer ability of the tube with twined coil insert are much higher than that of smooth tube. The ratio of Nusselt numbers of the tubes with and without insert is about 12.0-38.2, while the ratio of the friction factors of the tubes with and without insert is 7.7-18.1, when Reynolds number Re ranges from 400 to 1800. The maximum thermal performance factor JF can reach 2.16 at Re=1000. Correlations of Nusselt number Nu and the friction factor f with Re are presented.

Turbulent convective heat transfer in helical tube with twisted tape insert

Enhancement of heat transfer has been a main focus in thermal-fluid engineering field among the other aspects in industrial for decades. Despite numerous studies have been done on turbulent flows, helical tubes, and twisted tapes related to enhancement, no study has been done on the combination of all three components in augmentation of heat transfer. The objective of this study is to numerically investigate heat transfer of turbulent flow in helical tube with twisted tape insert subjected to constant wall temperature. A three-dimensional computational fluid dynamic model was developed and validated against experimental measured data and correlations. The model was then used to evaluate the turbulent convective heat transfer in straight and helical tube with and without twisted tape insert. To obtain comprehensive view on the heat transfer performance, the effect of twist ratio and inlet Reynolds number are evaluated as well. The insertion of twisted tape is found to increase the intensity of secondary flow in the radial direction. Helical tube with twisted tape insert was found to have higher heat transfer performance. The results show that for every case, the higher the inlet Reynolds number, the heat transfer increases proportionally while friction coefficient drops with decreasing amount of decrement. It is found that helical coiled tube with twisted tape at twist ratio of 7.86 has the highest performance among the configuration studied after taking consideration of heat transfer, friction coefficient and entropy generation. Finally, correlations of Nu and f are developed to predict the heat transfer and pressure drop within considered range of parameters in this study. This study serves as a foundation on the development of a high-performance heat exchanger for industrial application.

Direct numerical simulation of the turbulent flow and heat transfer of supercritical CO2 in a semicircular pipe

The heat transfer characteristics of supercritical carbon dioxide (SCO2) in micro-channels is a major concern in the thermal-hydraulic design of printed circuit heat exchangers (PCHEs). In the present study, direct numerical simulation was utilized to study the heat transfer of SCO2 in a semicircular pipe under mixed and forced convection. The inlet pressure and temperature were set to 8 MPa and 301.15 K to study the effects of thermophysical property variations on heat transfer. The Reynolds number at the pipe inlet was 4000, which is comparable to that of a PCHE channel. Emphasis is placed on revealing the effects of heat flux, secondary flow, thermal acceleration, corner effect, and geometric orientation on heat transfer. It was found that the temperature at the top wall was always higher than that at the bottom wall owing to the effects of buoyancy. A high-temperature region was identified near the pipe corner (known as the corner effect), which is caused by the combined effects of reduced velocity and small local hydraulic diameter. Secondary flows with two large vortices were observed in the channel cross-section. The secondary flow intensity was strengthened by the increase in heat flux. At the same time, the vortex centers bent toward the bottom at high heat fluxes. The orientation of the semicircular pipe has a large effect on the cross-sectional vector distribution and circumferential temperature gradient, which should be considered in the design of PCHEs.

Effects of cross-sectional geometry on flow characteristics in spiral separators

ABSTRACT As flowing film gravity concentrators, spiral separators are extensively used in the processing of numerous minerals. Appropriate design of their cross-sectional geometries has been known as an effective method to improve the performance of spiral separators. However, limited work has been published on the impact of cross-sectional geometry on flow field characteristics in spiral separators. In this study, the effects of cross-sectional geometries with various parabolic profiles (|x|=m|y| n ) of a spiral separator on the flow film thickness, flow pattern and flow regime were investigated by numerical simulation. The validity of the simulation approach was confirmed by the reasonably good agreement between the predicted and measured flow film thickness in the own laboratory spiral separator. Results have shown that the flow film thickness and the mean primary velocity in the inner and middle troughs are reduced by decreasing downward bevel angle or increasing parabolic index. The dominant region of the secondary flow can be expended inward by increasing the downward bevel angle and decreasing the parabolic index. As the radial position extends inward, a larger downward bevel angle is more conducive to improving the intensity of secondary flow. A wider laminar flow region can be obtained with a smaller downward bevel angle or a larger parabolic index. The flow film thickness has a significant positive correlation with the trough slope in the inner and middle troughs. It is recommended that the matching relationship between material properties and flow field characteristics should be fully considered when selecting the cross-sectional geometry. Thus, this study aids the structural design of the cross-sectional geometries of spiral separators.