Low Rotational Speed Research Articles

Evaluating the wear of cutting tools using a tunnel boring machine laboratory simulator

Purpose. One of the most common problems in mechanized excavation is the cutting tool wear, which has a great impact on the final cost of the project and its duration. Also, one of the most important factors affecting the wear of cutting tools is the operating parameters of the tunnel boring machine (TBM). Within the framework of this research, a tunnel boring machine laboratory simulator was designed and constructed to investigate the tunnel excavation process in the laboratory. Methods. A few of the features of this device are that it operates horizontally, has a low rotation speed, keeps the pins in contact with fresh soil throughout the test, and has the possibility of measuring the torque of the device during the test. A study of the cutting tool wear was conducted using granulation prepared from Tabriz metro line 2, as well as using operating parameters of mechanized excavation machines, such as penetration rate and cutter head rotation speed. Findings. The research results showed that by reducing the rotation speed of the cutter head from 35 to 10 rpm, the average wear of cutting tools is reduced by 63%. Also, by reducing the excavation time from 80 to 10 minutes, the cutting tool wear is reduced by 58%. The wear of cutting tool increases with increasing moisture content from 0 to 10%, and then decreases with increasing moisture content from 10 to 25%. Originality. During this research, a new device was designed and built to simulate tunnel excavation mechanisms. This laboratory simulator measures wear percentage, penetration rate and torque. Practical implications. There has been significant progress in predicting soil abrasion rates, but there are few accepted models for predicting cutting tool wear and soil abrasion rates. During the design and construction of the tunnel boring machine laboratory simulator, the effect of operating parameters on wear of cutting tool was examined.

Preparation of PP/PC light‐diffusing materials with UV‐shielding property

AbstractIn this study, we presented a one‐step melt‐blending method to fabricate polypropylene (PP)/polycarbonate (PC) light‐diffusing materials. A promising balance between haze and transmittance was obtained by the addition of small amount of PC to the matrix. On the basis of Mie scattering theory and morphology analysis, the correlation between processing conditions and light‐diffusing properties was built. Low rotor speed and high viscosity ratio were beneficial to optical properties of PP/PC composites. To extend the advanced application, two general anti‐ultraviolet additives nanoscale titanium dioxide (Nano‐TiO2) and 2‐(2‐hydroxy‐5‐methylphenyl) benzotriazole (UV‐P) were added to impart UV‐shielding property to the composites. Their specific influences on the morphology and comprehensive properties of PP/PC composites were studied. It was found that the introduction of Rayleigh scattering raised by Nano‐TiO2 could strengthen the scattering effect and cause a significant reduction in light transmittance, while UV‐P had little effect on the optical properties of the light‐diffusing composites. In summary, this study prepared the PP/PC composites with high‐performance light scattering and UV‐shielding properties applying a facile blending method, which showed a potential application in flexible lightings and LCD displays.

ANALISIS PENGARUH VARIASI DEBIT AIR TERHADAP KECEPATAN PUTARAN TURBIN CROSSFLOW PADA PEMBANGKIT LISTRIK TENAGA MIKROHIDRO

The Yeh Dikis River in Tabanan Regency Bali has a natural environment which is considered suitable to be used as a tourism destination. The factor that supports the Yeh Dikis River to become a tourism object is the river's potential to generate electricity. In this paper, a particular turbine for micro-hydro power plant is designed. The Yeh Dikis River has a water discharge of 0.381 m3/s with a head value of 8.2 meters, with a potential output power of 18.15 kW. The value of the water discharge and the output power are used to determine the type of turbine used. The computation and simulation showed that the crossflow turbine is suitable for the power plant. The analysis showed that a water discharge of 0.381 m3/s with a penstock diameter of 0.44 meters produces a specific rotational speed of 186 rpm; while a water discharge of 0.381 m3/s with a penstock diameter of 0.55 meters produces a turbine specification rotation speed of 160 rpm. This indicated that the effective head value affects the determination of the penstock diameter and the water velocity. The smaller diameter of the penstock produces, the higher the velocity of the water flow in the pipe. A low effective head will result in a low specific rotational speed. It was found that the optimum turbine power output for a water discharge of 0.381 m3/s with a penstock diameter of 0.44 meters is 18.15 kW. The work of the crossflow turbine is validated using a turbine simulator to determine the rotational speed of the turbine for a particular torque.

The Investigation of Two-Phase Expansion Performance with Indicator Diagram in a Twin-Screw Expander

Volumetric expanders are proven to be more suitable for small-scale waste heat recovery applications because of their simplicity, reliability, lower rotational speed and lower cost. Unlike turbines, volumetric expanders can work in the two-phase fluid state, which broadens their application fields. To investigate the two-phase performance of volumetric expanders, a specific twin-screw expander was chosen and modeled. The leakage loss and the suction pressure loss were primary concerns in this research. The two-phase expansion process in the expander is presented in detail using the developed mathematical model with an indicator diagram. The influence of several factors, including inlet vapor quality, rotational speed and intake pressure, are investigated. The influence mechanism of the vapor phase and the liquid phase on expander performance is clarified. In brief, this paper presents an illustrative understanding of the two-phase expansion process in twin-screw expanders.

Mathematical modeling of a hybrid magnetic gear for an autonomous low-power wind turbine

In traditional wind turbines, a mechanical gearbox is used to transmit the torque. This device converts the low rotation speed of the wind turbine blades into the high rotation speed of the generator shaft. Mechanical gearboxes are characterized by low reliability. They consist of rotating gears, all the torque between which is transmitted through the contact of the teeth at one point, which is accompanied by friction. Magnetic multipliers are more efficient than gear reducers. They contain no wearing parts and have a relatively high torque density. The modulator transforms the magnetic field between the inner and outer rotor, due to which the speed of rotation changes. This device has a number of advantages over a mechanical gearbox - the interaction between rotating elements (torque transmission) occurs over their entire area, while the gears of mechanical gearboxes perceive all the transmitted force at one point of contact between them. Research of autonomous wind turbines built on the basis of magnetic gearboxes is a relevant direction. This will reduce operating costs, increase the efficiency of converting wind energy into electricity, and increase the reliability of the wind turbine as a whole. The purpose of the work is the development of a two-dimensional field mathematical model of a hybrid magnetic gearbox for the evaluation of its parameters and characteristics and the optimization of its geometric dimensions. A generator with a built-in magnetic multiplier is the object of this study. The magnetic multiplier during operation creates a rotating magnetic field that can be used to induce emf in the generator winding. Such a generator is more compact than a gear drive, so this option was chosen as a prototype in this study. Geometrical models of a hybrid generator with a magnetic gearbox were developed and numerical field mathematical models were developed for the analysis of its parameters and characteristics. An analysis of the electromagnetic field and characteristics of the basic generator was carried out in the COMSOL Multiphysics software complex, on the basis of which optimization of its geometric dimensions was carried out to optimize mass and dimensional indicators

The Effect of Tool Rotation Speed on the Formation of Eutectic Structure during Friction Stir Welding of Aluminum to Magnesium

Friction stir welding (FSW) is a solid-state welding process capable of joining a wide range of light metals. However, liquation and solidification may occur during joining of dissimilar metals which leads to eutectic formation. This article aims to discover the influence of tool rotation speed on the formation of eutectic structure during friction stir welding of aluminum to magnesium. To do so, friction stir welding was performed at 600 and 950 rpm to join pure aluminum and ECO-AZ91 magnesium alloy in a lap configuration. In order to investigate the influence of the welding speed, the welding speeds of 23.5 and 37.5 mm/min were also chosen. Scanning electron microscopy (SEM) was used to study the microstructure of the joints. A shear-tensile test was used to evaluate the joints’ strengths. The fracture surfaces were also studied by SEM. The results revealed that changing the rotation speed directly affects the eutectic formation, whereas the welding speed had no influence. A lower rotation speed resulted in a thin, continuous intermetallic layer, whereas a higher speed led to the formation of a massive Mg-Al12Mg17 eutectic microstructure. The formation of eutectic, as an indicative of liquation, may affect the material flow during the process due to decreasing the friction coefficient between the tool and material. The macrostructure analyses showed that the phase evolution as well as the mechanism of material flow are highly affected by liquation.

A finger-snapping inspired bistable mechanism for converting low-frequency vibrations to high-speed rotation

Low-frequency vibrations can be exploited to drive a series of rotation-based devices (e.g. miniaturized centrifuges and energy harvesters), but their practical applications are hindered by the low rotation speeds of vibration-to-rotation conversion mechanisms. To address this issue, we report herein a finger-snapping inspired bistable mechanism that can achieve high-speed rotation out of low-frequency vibrations (<5 Hz). The proposed bistable mechanism consists of two sprung-cranks, a proof mass attached with a curved beam, and a pawl, in which the bistability is owed to the coupling of the potential energy of the springs with that of the deformed beam. Both theoretical simulations and experimental tests have been done to show the feasibility of the bistable mechanism. When triggered by vibrations with frequencies varying from 3.2 Hz to 4.5 Hz, the bistable mechanism can drive a rotor to rotate uni-directionally with high speeds ranging from 900 rpm to 1300 rpm. At a low vibration frequency of 3.2 Hz, around 290% increase in the rotation speed can be achieved by the bistable mechanism as compared with the corresponding linear mechanism (rack-and-pinion mechanism). The finger-snapping inspired bistable mechanism is thus a promising candidate in the tapping of ambient low-frequency vibrations as a green energy source for some mechatronic devices.

Study on Grinding Behavior Characteristics under Low-Speed Grinding Condition

In order to explore the crushing mechanism of minerals, this paper attempts to eliminate the throwing effect of media and study the grinding characteristics of minerals only under the action of abrasion force. In this paper, the method of removing the throwing state of media is to adjust the mill to a lower rotational speed, so that the grinding media are all in a cascading state. Three single-component pure minerals, quartz, pyrrhotite, and pyrite, commonly found in complex ores, were selected as research objects to study the grinding behavior characteristics of the three minerals only under the force of abrasion. The effects of mineral species, feed-particle sizes, grinding time, and other factors on the particle-size distribution and product-generation rate of grinding products are studied. The results show that from the particle-size distribution of grinding products, the yield of coarse particles is the highest, while the yield and t10 value of other fine particles are very low. The feed-particle size and the hardness of the mineral sample affect the grinding behavior. The product particle size is mainly 0.71 times the feed-particle size, and the other fine particle sizes generated are less than 0.5 times the feed-particle size.

Influence of differential longitudinal cyclic pitch on flight dynamics of coaxial compound helicopter

The Differential Longitudinal Cyclic Pitch (DLCP) in coaxial compound helicopter is found to be useful in mitigating low-speed rotor interactions and improving flight performance. The complex mutual interaction is simulated by a revised rotor aerodynamics model, where an improved Blade Element Momentum Theory (BEMT) is proposed. Comparisons with the rotor inflow distributions and aircraft trim results from literature validate the accuracy of the model. Then, the influence of the DLCP on the flight dynamics of the aircraft is analysed. The trim characteristics indicate that a negative DLCP can reduce collective and differential collective inputs in low speed forward flight, and the negative longitudinal gradient is alleviated. Moreover, a moderate DLCP can reduce the rotor and total power consumption by 4.68% and 2.9%, respectively. As DLCP further increases, the increased propeller power and unbalanced thrust allocation offset the improvement. In high-speed flight, DLCP does not improve the performance except for extra lateral and heading stick displacements. In addition, the tip clearance is degraded throughout the speed envelope due to the differential pitching moment and the higher thrust from the lower rotor. Meanwhile, the changed rotor efficiency and induced velocity alter low-speed dynamic stability and controllability. The pitch and roll subsidences are slightly degraded with the DLCP, while the heave subsidence, dutch roll and phugoid modes are improved. Lastly, the on-axis controllability, including collective, differential collective pitch, longitudinal and lateral cyclic pitches, varies with DLCP due to its effect on rotor efficiency and inflow distribution. In conclusion, a reasonable DLCP is recommended to adjust the rotor interaction and improve aircraft performance, and further to alter the flight dynamics and aerodynamics of aircraft.

Noise reduction on low Reynolds number rotors by boundary layer transition

Following force balance and acoustic measurements in an anechoic chamber, we have shown that promoting earlier boundary layer transition on an idealised low Reynolds number rotor using 3-D cylindrical roughness elements could lead to an interesting decrease in the noise emitted by the rotor. For most tripped cases, the aerodynamic performance of the rotor was impaired by tripping, but a reduction of the broadband noise and the high amplitude blade passing frequency harmonics were observed. On the contrary, the blade passing frequency and its first harmonics did not seem to be significantly affected by the presence of the tripping. The tripping was more effective at low rotational speeds, where the broadband noise contribution dominates the overall sound pressure level (OASPL), whereas the effect on OASPL is almost negligible at high rotational speeds, where the blade passing frequency noise becomes dominant. Careful selection of the roughness height with respect to the boundary thickness and inter-roughness spacing showed that aerodynamic performance loss can be minimised while preserving the gain in noise reduction.

Performance Investigation and Experimental Testing of a Stator-PM-Excitation Axial-Flux Magnetic Gear

This paper proposes a stator-excitation axial-flux magnetic gear (SEAMG) based on innovative improvement from rotor excitation to stator excitation for the magnetic gear. The key design of the proposed SEAMG is to place the permanent magnets (PMs) on the stator, aiming at only retaining iron on rotors to enhance its mechanical robustness, and the PMs located on the stator can be avoided falling off to further improve operation reliability. An axial-flux pattern is adopted so as to make that the stator can be easily fixed to the housing and the high- and low-speed rotor shafts can be conveniently led out from axial side. Hence, compared with the existing coaxial rotor-excitation MGs, the proposed SEAMG has improved mechanical reliability and low processing difficulty. Its operation principle is explained and the general optimization design considerations are illustrated to achieve expected torque transmission performance. A prototype is built and performance evaluation using the 3-D finite element analysis (FEA) and the experiments is conducted to verify its validity.

Relationship Between The Co-Continuous Morphology of Immiscible Polymer Blends and the Structure of An In Situ Formed Graft Copolymer.

Suitable compatibilizers are essential to prepare immiscible polymer blends with stable co-continuous morphologies. From the thermodynamic point of view, such compatibilizer should not only reduce the interfacial tension, but also promote the formation of flat interface between different phases. Meanwhile, it must not hinder the coalescence of dispersed phase. Therefore, asymmetric structures are required for those block or graft copolymer compatibilizers. However, from the kinetic point of view, copolymers with asymmetric structures are prone to be dragged out from the interface and form micelles in one phase under the processing conditions, which will lose their compatibilization effects. The balance between such thermodynamic and kinetic factors remains unclear. In this paper, the relationship between the morphology of the compatibilized polystyrene/nylon 6/styrene-maleic anhydride copolymers (PS/PA6/SMA) immiscible polymer blends and the structures of the in-situ formed SMA-g-PA6 graft copolymers as well as the processing conditions are studied. Two kinds of SMA are used as compatibilizers: SMA28 (Mw = 110,000g/mol, MAH content 28wt.%) and SMA11 (Mw = 110,000g/mol, MAH content 11wt.%). After melt blending with PA6 into an internal mixer, the in-situ formed copolymer SMA28-g-PA6 has an average four PA6 side chains grafted on one SMA backbone, while that of SMA11-g-PA6 has only one PA6 side chain. Dissipative particle dynamics (DPD) simulation results indicate that both SMA28-g-PA6 copolymer and PS/PA6/SMA28 blends tend to form co-continuous structure, while SMA11-g-PA6 copolymer and PS/PA6/SMA11 blends form sea-island morphologies. However, these results are confirmed experimentally only at relatively low rotor speed of the internal mixer (60rpm). When the rotor speed of the mixer is higher (105rpm), sea-island morphologies are obtained in PS/PA6/SMA28 blends and co-continuous ones are found in PS/PA6/SMA11 systems. These results indicate that higher shear stress will favor to elongate the minor phase domains and form flat interfaces, which is benefit for the formation of co-continuous morphologies; meanwhile, high shear stress may pull the graft copolymers with asymmetric structures (SMA28-g-PA6) out from the interface of PS and PA6 and induce the formation of sea island morphologies. This article is protected by copyright. All rights reserved.

Effect of Low Welding and Rotational Speed on Microstructure and Mechanical Behaviour of Friction Stir Welded AZ31-AA6061-T6

Effect of Low Welding and Rotational Speed on Microstructure and Mechanical Behaviour of Friction Stir Welded AZ31-AA6061-T6

An Analysis of the Design of a Low Rotational Speed Permanent Magnet Generator That Uses Radial Flux

A radial flux permanent magnet generator can be effectively used in generating wind power at low speeds. This generator uses a combination of permanent magnets and a stator to produce electricity from the wind’s kinetic energy. The permanent magnets are arranged in a radial pattern, which reduces the amount of heat lost and therefore increases the generator’s efficiency. This design allows for a low rotational speed, which makes it suitable for applications such as wind turbines. The air gap between the rotor and the stator affects the output voltage and power due to the decrease in magnetic flux. This study aims to increase the generator’s output voltage and output power by fitting stator teeth widths to the stator teeth. The stator teeth width fitting design method adjusts the air gap between the stator and the rotor to a uniform size. This helps to reduce the pulsating torque and ensure that the output voltage and power are maximized. The three variables are the stator slot width, the rotor slot width, and the air gap width. By adjusting these variables, the stator teeth width fitting design method can adjust the air gap between the stator and rotor.

Lubrication characteristics and thermal deformation of hydrostatic thrust bearing based on conjugate heat transfer

PurposeThe purpose of this paper is to analyze the variation of temperature field, pressure field and deformation of hydrostatic thrust bearing under different working conditions, so as to provide a theoretical basis for improving accuracy and reliability.Design/methodology/approachIn this study, the double rectangular hydrostatic bearing of type Q1-224 was selected as the research object, and the simulation was carried out according to different working conditions, and the obtained data were summarized regularly.FindingsIt is found that the overall temperature of hydrostatic bearing increases with the increase of speed and load, and the increase in load will result in a larger pressure distribution which first increases and then decreases with the speed. The deformation trend of the deformation field is found, and it is found that the force deformation is larger than the thermal deformation at low rotational speed, and the thermal deformation is larger than the force deformation at high rotational speed.Originality/valueIn this study, the fluid-structure coupling method of conjugate heat transfer is applied to study the whole hydrostatic bearing. Most of the previous studies only studied the oil film and considered the influence of the convective heat transfer between the hydrostatic bearing and the air in heat transfer, which is rarely seen in the previous research literature.

Study on modeling test method and the critical Reynolds number of a micro centrifugal pump

In order to test the performance of the micro centrifugal pump and carry out performance analysis by using water instead of blood as the test medium, a modeling test method of the micro centrifugal pump was proposed in this paper. Dimensional analysis method was applied to study the dimensionless characteristic number of the micro centrifugal pump. The SST (Shear Stress Transport) k-ω model was used to simulate the flow in the prototype pump and model pump. The correctness of the similarity theory and modeling schemes was verified. The performance of the micro centrifugal pump for transporting water and blood was studied under the same working conditions, and the effect of Reynolds number on the performance of the micro centrifugal pump was discussed. The external characteristics of similar pumps can be converted to each other. For similar pumps under different modeling schemes, the pressure and velocity at the corresponding position is proportional. When the micro centrifugal pump that transports blood operates at low rotational speed and low flow rate, the performance of the micro centrifugal pump will change dramatically. The critical Reynolds number of the micro centrifugal pump is determined to be 1200. The similarity criterion between the prototype pump and model pump was established. The modeling schemes of the micro centrifugal pump were formulated. The critical Reynolds number of the micro centrifugal pump was determined. The research results provide a new method for the performance test of the micro centrifugal pump transporting blood.

Preparation of Mg2Ni Hydrogen Storage Alloy Materials with Mg-Coated Structure by Mechanical Alloying

In this paper, a hydrogen storage alloy material with good hydrogen storage performance, high preparation efficiency and a partially amorphous magnesium-coated Mg2Ni structure was prepared by high-energy ball milling mechanical alloying. The effects of different Mg and Ni mass ratios and ball milling speed on their synthesis were investigated. The results show that compared with the Mg2Ni alloy, the thermodynamic and kinetic properties of the hydrogen storage alloy material change less, but the hydrogen storage capacity increases significantly. In the case of different Mg and Ni mass ratios, the formation time of Mg2Ni alloys is not much different, the obtained particle sizes are all about 5 μm, and the hydrogen storage capacity increases with the increase of mass ratio. However, the formation of Mg2Ni alloy varies greatly at different rotational speeds. At low rotational speed, the formation of Mg2Ni alloy is incomplete or not, and the rotational speed for complete formation of Mg2Ni alloy is 1000/1100 rpm. Through SEM and XRD analysis, it is found that the particle size of the alloy after ball milling is small, and the alloy composition is uniform, which is one of the reasons for the better hydrogen storage performance of the alloy. And it can be seen that the alloy with extremely high phase purity can be obtained by ball milling for 5 h. Through TEM, Mapping and PCT curves combined with XRD analysis, it is found that the particles after ball milling have a structure of partially amorphous Mg-coated Mg2Ni alloy, and the hydrogen storage capacity of the alloy reaches 5 wt%. This is another reason for the two-stage plateau pressure and better hydrogen storage performance. Therefore, the Mg2Ni alloy obtained by the high-energy ball milling mechanical alloying method in this paper has a 90% increase in efficiency compared with the traditional mechanical alloying method; and compared with the melting method, the hydrogen storage performance is also improved.

Preparation and optical-electronic properties of thin films comprising P3HT and few-layer graphene nanosheets

The present work investigates the production of thin films from nanocomposites obtained by solution mixing a synthesized P3HT with different proportions of few-layered graphene (FLG) in chloroform and its influence on crystallography and light absorption in the visible region. Commercial FLG produced through exfoliation in the liquid phase assisted by a non-anionic surfactant was employed, being a material not yet tested for the production of nanocomposites, let alone to be applied in photovoltaic cells. The deposition of thin films was evaluated at low (1000 rpm) and high (2500 rpm) rotation speeds in a dynamic and static deposition process. In addition, the annealing heat treatment in the optimized thin films was evaluated. The results showed that the P3HT was synthesized with suitable molar mass, regioregularity, and thermal resistance as characterized by the analyses of gel permeation chromatography (GPC), 1H-nuclear magnetic resonance (1H NMR), and thermogravimetric analysis (TGA). The thin films produced showed that the FLG enlarged and strengthened the P3HT absorption, increasing the absorption region by up to 34 % in addition to improving the resolution of the absorption peaks favoring the π-π* transition, which is important for the photovoltaic effect. By the X-ray diffraction analysis, it can be suggested that incorporating the FLG improves the charge mobility as there was an increase in the crystallite size without changing the interplanar distance. Based on these results, it can be suggested that P3HT/FLG nanocomposites are promising for application in both the active and hole transport layers of solar cells.

Effect of substrate rotation speed on AlGaN nanowire deep ultraviolet light-emitting diodes by molecular beam epitaxy

Aluminum gallium nitride (AlGaN) nanowires by molecular beam epitaxy (MBE) have become an emerging platform for semiconductor deep ultraviolet (UV) light-emitting diodes (LEDs). Despite of the progress, much less attention has been paid to the effect of substrate rotation speed on the device performance. Herein, we investigate the effect of the substrate rotation speed on the nanowire height and diameter uniformity, as well as the electrical and optical performance of MBE-grown AlGaN nanowire deep UV LED structures with low and high substrate rotation speeds. It is found that by increasing the substrate rotation speed from 4 revolutions per minute (rpm) to 15 rpm, the statistical variation of the nanowire height and diameter is reduced significantly. Increasing the substrate rotation speed also improves the device electrical performance, with a factor of 4 reduction on the device series resistance. This improved electrical performance further transfers to the improved optical performance. The underlying mechanisms for these improvements are also discussed.

Hemodynamic investigation of a novel rotary displacement blood pump for extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) is a life support system used in the treatment of severe respiratory and circulatory failure. High shear stress caused by the high rotational speed of centrifugal blood pumps can cause hemolysis and platelet activation, which are among the major factors leading to the complications of the ECMO system. In this study, a novel blood pump named rotary displacement blood pump (RDBP), which can considerably reduce rotational speed and shear stress while ensuring the normal pressure flow relationship, was proposed. We employed computational fluid dynamics (CFD) analysis to investigate the performance of RDBP under adult ECMO support operating conditions (5 L/min with 350 mmHg). The efficiency and H-Q curves of the RDBP were calculated to evaluate its hydraulic performance, and pressure, flow patterns, and shear stress distribution were analyzed to estimate the hemodynamic characteristics in the pump. In addition, the modified index of hemolysis (MIH) was calculated for the RDBP based on a Eulerian approach. The hydraulic efficiency of the RDBP was 47.28%. The velocity distribution of flow field in the pump was relatively uniform. Most of the liquid (more than 75%) in the pump was exposed to low scale shear stress (<1 Pa), which was close to normal physiological conditions. The gap area was the main distribution location of high scale shear stress. The high wall shear stress (>9 Pa) volume fraction of the RDBP was small and located in the boundary areas between the rotor's edge and the housing. The MIH value of the RDBP was 9.87 ± 0.93 (mean ± SD). The RDBP can achieve better hydraulic efficiency and hemodynamic performance at lower rotational speed. The design of this novel pump is expected to provide a new direction for developing a blood pump for ECMO.