Design, fabrication and experimental studies of compliant flexure diaphragm for micro pump

This study reports the performance of piezo actuated compliant flexure diaphragm for micropump and MEMS application. To achieve the high performance of diaphragm at the low operating voltage compliant flexure diaphragm design is introduced. Very limited work has done on the diaphragms of micropump. Large numbers of mechanical micropumps have used plane diaphragms. The central deflection of diaphragm plays an important role in defining the micropump performance. The flow rate of mechanical type micropump strongly depends on the central deflection of diaphragm. In this paper compliant flexure diaphragms are designed for micropump to achieve higher deflection at lower operating voltage. Finite element analysis of compliant flexure diaphragm with single layer PVDF (Polyvinylidene fluoride) actuator is simulated in COMSOL. Compliant flexure diaphragms with a different number of flexures are analyzed. The central deflection of compliant flexure diaphragms is measured for driving voltages of 90V to 140V in 10 steps. The deflection of the compliant flexure diaphragm mainly depends on flexure width and length, the number of flexures in the diaphragm, PVDF thickness, diaphragm thickness and driving voltage. Use of compliant flexure diaphragm for micropump will reduce the mass and driving voltage of micropump. An attempt is made to compare the results of compliant flexure diaphragms with plane diaphragms. From the experimental results it is noticed that the compliant flexure diaphragm deflection is twice that of the plane diaphragm at same driving voltage. Deflection of three flexure and four flexure compliant diaphragms is 10.5µm and 11.5µm respectively at 140V.

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Novel design, analytical and experimental studies of a piezoelectric ultrasonic linear actuator based on binate feet driving

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x17721043 ◽

2017 ◽

Vol 29 (5) ◽

pp. 787-799 ◽

Cited By ~ 3

Author(s):

Shupeng Wang ◽

Weibin Rong ◽

Lefeng Wang ◽

Zhichao Pei ◽

Lining Sun

Keyword(s):

Experimental Studies ◽

Experimental System ◽

Step Length ◽

Linear Actuator ◽

Driving Mechanism ◽

Driving Voltage ◽

Loading Capacity ◽

Driving Frequency ◽

Element Analysis ◽

Novel Design

This article presents the piezoelectric ultrasonic linear actuator based on binate feet driving. The actuator is equipped with a rhombus binate feet mechanism to generate two synchronous rectangle driving trajectories. With the help of the two synchronous trajectories, the proposed actuator can deliver stable long-range motion (the designed maximum stroke is 19 mm) accompanying with large loading capacity and high driving resolution. The configuration and operational principle are described in detail and the driving trajectory of the binate feet is analyzed. Finite element analysis is conducted to investigate the static deformation and stress status of the driving mechanism at every step. The experimental system is established to test the performance of the actuator prototype and the results indicate that the prototype can be operated stably step by step and all steps have high reproducibility. The driving resolution (minimum step length) of the actuator prototype is 25.9 nm. The maximum loading capacity and the maximum thrust are 37.2 and 3.2 N, respectively. The experimental results also confirm that the designed actuator can achieve various motion velocities by changing the driving voltage and driving frequency.

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Design of Star-Shaped Flextensional Stator for Ultrasonic Motor

Advances in Mechanical Engineering ◽

10.1155/2014/162535 ◽

2014 ◽

Vol 6 ◽

pp. 162535 ◽

Cited By ~ 2

Author(s):

Lien-Kai Chang ◽

Mi-Ching Tsai

Keyword(s):

Normal Force ◽

Piezoelectric Actuators ◽

Operating Voltage ◽

Driving Voltage ◽

Element Analysis ◽

Voltage Range ◽

Resonance Frequencies ◽

The Finite Element Analysis ◽

Sensitivity Analysis Method ◽

Stator Design

When a driving voltage opposite to the piezoelectric polarity is applied on the flextensional stator, it will generate the normal force, of which the operating voltage range of piezoelectric actuators will decrease. This paper presents a novel stator design for producing the normal force in which the driving voltage has the same piezoelectric polarity, which is based on the structure of two multilayer piezoelectric actuators clamped in a star-shaped shell. To obtain the two close resonance frequencies of flexural and translation modes, a genetic algorithm combined with the finite element analysis is employed to find the optimal dimensions for the geometry of the stator. The importance of each design parameter is evaluated through a proposed sensitivity analysis method. A prototype resulting from the optimal design was fabricated and the experimental results are given to show that the stator can generate, in practice, the required coupling resonance mode between 35.15 kHz and 36.49 kHz.

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Numerical Modelling of Concrete-to-UHPC Bond Strength

Materials ◽

10.3390/ma13061379 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1379 ◽

Cited By ~ 6

Author(s):

Alireza Valikhani ◽

Azadeh Jaberi Jahromi ◽

Islam M. Mantawy ◽

Atorod Azizinamini

Keyword(s):

Bond Strength ◽

High Performance ◽

High Performance Concrete ◽

Experimental Studies ◽

Structural Behaviour ◽

Ultra High Performance Concrete ◽

Direct Tension ◽

Element Analysis ◽

Additional Material ◽

Volume Model

Ultra-High Performance Concrete (UHPC) has been a material of interest for retrofitting reinforced concrete elements because of its pioneer mechanical and material properties. Numerous experimental studies for retrofitting concrete structures have shown an improvement in durability performance and structural behaviour. However, conservative and sometimes erroneous estimates for bond strength are used for numerically calculating the strength of the composite members. In addition, different roughening methods have been used to improve the bond mechanism; however, there is a lack of numerical simulation for the force transfer mechanism between the concrete substrate and UHPC as a repair material. This paper presents an experimental and numerical programme designed to characterize the interfacial properties of concrete substrate and its effect on the bond strength between the two materials. The experimental programme evaluates the bond strength between the concrete substrates and UHPC with two different surface preparations while using bi-surface test and additional material tests, including cylinder and cube tests for compression property, direct tension test, and flexural test to complement UHPC tensile properties. Non-linear finite element analysis was conducted, which uses a numerical zero thickness volume model to define the interface bond instead of a traditional fixed contact model. The numerical results from the zero thickness volume model show good agreement with the experimental results with a reduction in error by 181% and 24% for smooth and rough interface surfaces if compared to the results from the model with a fixed contact.

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Parallel Computing for Tire Simulations

Tire Science and Technology ◽

10.2346/1.3637743 ◽

2011 ◽

Vol 39 (3) ◽

pp. 193-209 ◽

Cited By ~ 2

Author(s):

H. Surendranath ◽

M. Dunbar

Keyword(s):

High Performance ◽

Effective Means ◽

Cost Effective ◽

Turnaround Time ◽

Careful Consideration ◽

Rolling Contact ◽

Element Analysis ◽

Parallel Solvers ◽

Design Changes ◽

Highly Nonlinear

Abstract Over the last few decades, finite element analysis has become an integral part of the overall tire design process. Engineers need to perform a number of different simulations to evaluate new designs and study the effect of proposed design changes. However, tires pose formidable simulation challenges due to the presence of highly nonlinear rubber compounds, embedded reinforcements, complex tread geometries, rolling contact, and large deformations. Accurate simulation requires careful consideration of these factors, resulting in the extensive turnaround time, often times prolonging the design cycle. Therefore, it is extremely critical to explore means to reduce the turnaround time while producing reliable results. Compute clusters have recently become a cost effective means to perform high performance computing (HPC). Distributed memory parallel solvers designed to take advantage of compute clusters have become increasingly popular. In this paper, we examine the use of HPC for various tire simulations and demonstrate how it can significantly reduce simulation turnaround time. Abaqus/Standard is used for routine tire simulations like footprint and steady state rolling. Abaqus/Explicit is used for transient rolling and hydroplaning simulations. The run times and scaling data corresponding to models of various sizes and complexity are presented.

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Accelerated testing of super lightweight UHPC waffle deck under heavy vehicle simulator

Bridge Structures ◽

10.3233/brs-200176 ◽

2021 ◽

Vol 16 (2-3) ◽

pp. 61-74

Author(s):

Sahar Ghasemi ◽

Amir Mirmiran ◽

Yulin Xiao ◽

Kevin Mackie

Keyword(s):

High Performance ◽

Failure Modes ◽

High Performance Concrete ◽

High Strength ◽

Heavy Vehicle ◽

Wheel Load ◽

Element Analysis ◽

Vehicle Simulator ◽

Pavement Testing ◽

Heavy Vehicle Simulator

A super lightweight deck can enhance load rating and functionality of a bridge, especially those identified as structurally deficient. This study was aimed to develop and experimentally validate a novel bridge deck as an ultra-lightweight low-profile waffle slab of ultra-high-performance concrete (UHPC) with either carbon fiber reinforced polymer (CFRP) or high strength steel (HSS) reinforcement. The proposed system lends itself to accelerated bridge construction, rapid deck replacement in bridges with load restrictions, and bridge widening applications without the need to replace girders. Performance and failure modes of the proposed deck were initially assessed through extensive lab experiments and finite element analysis, which together confirmed that the proposed deck panel meets the AASHTO LRFD requirements. The proposed deck system is not susceptible to punching shear of its thin slab and fails in a rather ductile manner. To evaluate its long-term performance, the system was further tested under the dynamic impact of wheel load at the Accelerated Pavement Testing (APT) facility of the Florida Department of Transportation using a Heavy Vehicle Simulator (HVS).

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Recent Advances in ZnO-Based Carbon Monoxide Sensors: Role of Doping

Sensors ◽

10.3390/s21134425 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4425

Author(s):

Ana María Pineda-Reyes ◽

María R. Herrera-Rivera ◽

Hugo Rojas-Chávez ◽

Heriberto Cruz-Martínez ◽

Dora I. Medina

Keyword(s):

Carbon Monoxide ◽

High Performance ◽

Gas Sensing ◽

Experimental Studies ◽

Electrical Performance ◽

Long Term Stability ◽

Sensing Applications ◽

Recent Advances ◽

Sensitivity And Selectivity ◽

Doped Zno

Monitoring and detecting carbon monoxide (CO) are critical because this gas is toxic and harmful to the ecosystem. In this respect, designing high-performance gas sensors for CO detection is necessary. Zinc oxide-based materials are promising for use as CO sensors, owing to their good sensing response, electrical performance, cost-effectiveness, long-term stability, low power consumption, ease of manufacturing, chemical stability, and non-toxicity. Nevertheless, further progress in gas sensing requires improving the selectivity and sensitivity, and lowering the operating temperature. Recently, different strategies have been implemented to improve the sensitivity and selectivity of ZnO to CO, highlighting the doping of ZnO. Many studies concluded that doped ZnO demonstrates better sensing properties than those of undoped ZnO in detecting CO. Therefore, in this review, we analyze and discuss, in detail, the recent advances in doped ZnO for CO sensing applications. First, experimental studies on ZnO doped with transition metals, boron group elements, and alkaline earth metals as CO sensors are comprehensively reviewed. We then focused on analyzing theoretical and combined experimental–theoretical studies. Finally, we present the conclusions and some perspectives for future investigations in the context of advancements in CO sensing using doped ZnO, which include room-temperature gas sensing.

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Electromagnetic-Thermal Integration Design of Permanent Magnet Motor for Vehicles

International Journal of Rotating Machinery ◽

10.1155/2019/9653231 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Shijun Chen ◽

Qi Zhang ◽

Surong Huang

Keyword(s):

Permanent Magnet ◽

High Performance ◽

Design Method ◽

Electromagnetic Properties ◽

Permanent Magnet Motor ◽

Element Analysis ◽

Experiment Platform ◽

Motor Design ◽

Dimensional Parameters ◽

Thermal Integration

To more efficiently design high performance vehicular permanent magnet motor, an electromagnetic-thermal integration design method is presented, which considers both the electromagnetic properties and the temperature rise of motor winding when determining the main dimensional parameters of the motor. Then a 48-slot and 8-pole vehicular permanent magnet motor is designed with this method. The thermomagnetic coupling design is simulated and validated on the basis of multiphysical domain on finite element analysis. Then the prototype is analyzed and tested on a newly built motor experiment platform. It is shown that the simulation results and experimental results are consistent, which validate the accuracy and effectiveness of the new design method. Also this method is proved to well improve the efficiency of permanent magnet motor design.

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2D MoS2 Encapsulated Silicon Nanopillar Array with High-Performance Light Trapping Obtained by Direct CVD Process

Crystals ◽

10.3390/cryst11030267 ◽

2021 ◽

Vol 11 (3) ◽

pp. 267

Author(s):

Minyu Bai ◽

Zhuoman Wang ◽

Jijie Zhao ◽

Shuai Wen ◽

Peiru Zhang ◽

...

Keyword(s):

Silicon Substrate ◽

High Performance ◽

Low Cost ◽

Light Trapping ◽

Incident Light ◽

Single Layer ◽

Chemical Vapor ◽

Optoelectronic Device ◽

Planar Silicon ◽

Shortwave Infrared

Weak absorption remains a vital factor that limits the application of two-dimensional (2D) materials due to the atomic thickness of those materials. In this work, a direct chemical vapor deposition (CVD) process was applied to achieve 2D MoS2 encapsulation onto the silicon nanopillar array substrate (NPAS). Single-layer 2D MoS2 monocrystal sheets were obtained, and the percentage of the encapsulated surface of NPAS was up to 80%. The reflection and transmittance of incident light of our 2D MoS2-encapsulated silicon substrate within visible to shortwave infrared were significantly reduced compared with the counterpart planar silicon substrate, leading to effective light trapping in NPAS. The proposed method provides a method of conformal deposition upon NPAS that combines the advantages of both 2D MoS2 and its substrate. Furthermore, the method is feasible and low-cost, providing a promising process for high-performance optoelectronic device development.

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High-performance magneto-rheological clutches for direct-drive actuation: Design and development

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x211006902 ◽

2021 ◽

pp. 1045389X2110069

Author(s):

Sergey Pisetskiy ◽

Mehrdad Kermani

Keyword(s):

High Performance ◽

Degrees Of Freedom ◽

Dynamic Range ◽

Complete Analysis ◽

Mass Ratio ◽

Direct Drive ◽

Element Analysis ◽

Prototype Development ◽

Magneto Rheological ◽

Hall Sensors

This paper presents an improved design, complete analysis, and prototype development of high torque-to-mass ratio Magneto-Rheological (MR) clutches. The proposed MR clutches are intended as the main actuation mechanism of a robotic manipulator with five degrees of freedom. Multiple steps to increase the toque-to-mass ratio of the clutch are evaluated and implemented in one design. First, we focus on the Hall sensors’ configuration. Our proposed MR clutches feature embedded Hall sensors for the indirect torque measurement. A new arrangement of the sensors with no effect on the magnetic reluctance of the clutch is presented. Second, we improve the magnetization of the MR clutch. We utilize a new hybrid design that features a combination of an electromagnetic coil and a permanent magnet for improved torque-to-mass ratio. Third, the gap size reduction in the hybrid MR clutch is introduced and the effect of such reduction on maximum torque and the dynamic range of MR clutch is investigated. Finally, the design for a pair of MR clutches with a shared magnetic core for antagonistic actuation of the robot joint is presented and experimentally validated. The details of each approach are discussed and the results of the finite element analysis are used to highlight the required engineering steps and to demonstrate the improvements achieved. Using the proposed design, several prototypes of the MR clutch with various torque capacities ranging from 15 to 200 N·m are developed, assembled, and tested. The experimental results demonstrate the performance of the proposed design and validate the accuracy of the analysis used for the development.

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Computational and experimental mechanical performance of a new everolimus-eluting stent purpose-built for left main interventions

Scientific Reports ◽

10.1038/s41598-021-87908-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Saurabhi Samant ◽

Wei Wu ◽

Shijia Zhao ◽

Behram Khan ◽

Mohammadali Sharzehee ◽

...

Keyword(s):

Structural Integrity ◽

Mechanical Performance ◽

Experimental Studies ◽

Patient Specific ◽

Wall Structure ◽

Left Main ◽

Element Analysis ◽

Stent Expansion ◽

Radial Strength ◽

Different Diameters

AbstractLeft main (LM) coronary artery bifurcation stenting is a challenging topic due to the distinct anatomy and wall structure of LM. In this work, we investigated computationally and experimentally the mechanical performance of a novel everolimus-eluting stent (SYNERGY MEGATRON) purpose-built for interventions to large proximal coronary segments, including LM. MEGATRON stent has been purposefully designed to sustain its structural integrity at higher expansion diameters and to provide optimal lumen coverage. Four patient-specific LM geometries were 3D reconstructed and stented computationally with finite element analysis in a well-validated computational stent simulation platform under different homogeneous and heterogeneous plaque conditions. Four different everolimus-eluting stent designs (9-peak prototype MEGATRON, 10-peak prototype MEGATRON, 12-peak MEGATRON, and SYNERGY) were deployed computationally in all bifurcation geometries at three different diameters (i.e., 3.5, 4.5, and 5.0 mm). The stent designs were also expanded experimentally from 3.5 to 5.0 mm (blind analysis). Stent morphometric and biomechanical indices were calculated in the computational and experimental studies. In the computational studies the 12-peak MEGATRON exhibited significantly greater expansion, better scaffolding, smaller vessel prolapse, and greater radial strength (expressed as normalized hoop force) than the 9-peak MEGATRON, 10-peak MEGATRON, or SYNERGY (p < 0.05). Larger stent expansion diameters had significantly better radial strength and worse scaffolding than smaller stent diameters (p < 0.001). Computational stenting showed comparable scaffolding and radial strength with experimental stenting. 12-peak MEGATRON exhibited better mechanical performance than the 9-peak MEGATRON, 10-peak MEGATRON, or SYNERGY. Patient-specific computational LM stenting simulations can accurately reproduce experimental stent testing, providing an attractive framework for cost- and time-effective stent research and development.

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