Membrane Deflection Analysis of the Intelligent Micro-Sensor/Pump Under the Consideration of Micro-Viscosity and Membrane Pillar

2005 ◽  
Author(s):  
T. C. Yih ◽  
Shalini R. Gillella
Keyword(s):  
Applied Pressure ◽  
External Pressure ◽  
Structure Design ◽  
Design Parameters ◽  
Membrane Thickness ◽  
Design Development ◽  
Viscosity Effect ◽  
Micro Pump ◽  
Micro Sensor ◽  
Membrane Deflection

New emerging technologies such as MEMS “Micro-Electro-Mechanical Systems” provides many promising opportunities for developing innovative methods. This research focuses on the design, development and analysis of functional micro-pumps. Micro-pumps open new frontiers of engineering applications where precise fluid amounts to a targeted location are required. Micro-pumps can be used in environmental monitoring, where localized water quality measurements are needed, chemical/biological detection and analysis, and industrial process control. Conventional MEMS micro-pumps are driven by micro-actuators, which add complication to micro-pump membrane/structure design, control, and fabrication. The proposed MEMS micro-pump will have its membrane (or diaphragm) be sensitive to external pressure change and self-actuated in response to a designated pressure level; thus named IMSP (intelligent micro-sensor/pump). This paper provides a detailed study of membrane deflection which is one of the most important component of micro-pump. The membrane of the conventional design has uniform thickness. The novel smart micro-pump has a membrane pillar in the center. This membrane pillar has advantages of greater stability, larger pumping force and longer life cycle. The deflection of the membrane is analyzed and compared in two cases: 1) Membrane deflection without membrane pillar, and 2) Membrane deflection with membrane pillar. The micro-viscosity effect on a micro-pump will be augmented as the size of the micro-pump becomes smaller, especially in the micron range. Therefore two more cases are analyzed under the consideration of micro-viscosity effect: 1) Membrane deflection with micro-viscosity effect and without membrane pillar, and 2) Membrane deflection with micro-viscosity effect and with membrane pillar. The critical design parameters of the membrane—thickness and diameter—are varied and substituted into the governing equations to calculate the membrane deflection. The curves of membrane deflection versus the applied pressure on the membrane are plotted for further characterization of the micro-pump. This study will lead to the full development of a smart micro-pump and set off a new research direction.

Structure Design and Optimization of Vacuum Vessel for Spacecraft Thermal Test

2013 ◽  
Vol 390 ◽  
pp. 665-669
Author(s):  
Xiao Han ◽  
Bo Tao Liu ◽  
Shi Zeng Lyu ◽  
Yan Qi ◽  
Feng Guo
Keyword(s):  
External Pressure ◽  
Structure Design ◽  
The Body ◽  
Space Environment ◽  
Design Parameters ◽  
Main Body ◽  
Vacuum Vessel ◽  
Element Analysis ◽  
Design And Optimization ◽  
Thermal Test

The space environment simulator is a facility used to conduct thermal test for spacecraft, and vacuum vessel is the main body of it. During the test process, the vacuum vessel is exerted an external pressure of 0.1MPa, and there are various pipe orifices on the body of the vessel, therefore the intensity and stability should be taken into account carefully. This paper introduces three approaches for the design of structure intensity and stability of vacuum vessel, and takes GVU-600 space environment simulator as an example, which is the first aerospace facility developed by China for Russia. One approach is calculation by rules, and the second method utilizing finite element analysis, which could check details of the structure, but the efficiency of the previous two methods is low. In the end, a mathematics approach is introduced, which utilizes the optimization model, and the design parameters could be calculated accurately and efficiently.

Design of a wheeled wall climbing robot based on the performance of bio-inspired dry adhesive material

Robotica ◽  
2021 ◽  
pp. 1-14
Author(s):  
Hongkai Li ◽  
Xianfei Sun ◽  
Zishuo Chen ◽  
Lei Zhang ◽  
Hongchao Wang ◽  
...  
Keyword(s):  
Flat Surface ◽  
Thrust Force ◽  
Adhesion Force ◽  
Structure Design ◽  
Design Parameters ◽  
Climbing Robot ◽  
Adhesive Material ◽  
Ducted Fan ◽  
The Stability ◽  
Belt System

Abstract Inspired by gecko’s adhesive feet, a wheeled wall climbing robot is designed in this paper with the synchronized gears and belt system acting as the wheels by considering both motion efficiency and adhesive capability. Adhesion of wheels is obtained by the bio-inspired adhesive material wrapping on the outer surface of wheels. A ducted fan mounted on the back of the robot supplies thrust force for the adhesive material to generate normal and shear adhesion force whilemoving on vertical surfaces. Experimental verification of robot climbing on vertical flat surface was carried out. The stability and the effect of structure design parameters were analyzed.

SLS Class 3D Woven Composite End Ring Structure Design, Development, and Verification Testing

2022 ◽  
Author(s):  
Kenneth N. Segal ◽  
Babak Farrokh ◽  
Andrew Bergan ◽  
Arunkumar Satyanarayana ◽  
David W. Sleight ◽  
...  
Keyword(s):  
Ring Structure ◽  
Structure Design ◽  
Design Development ◽  
Woven Composite

Uncertainty in Collapse Strength Prediction of Sandwich Pipelines

2021 ◽  
Author(s):  
U. Bhardwaj ◽  
A. P. Teixeira ◽  
C. Guedes Soares
Keyword(s):  
Probabilistic Models ◽  
Uncertainty Propagation ◽  
Simulation Method ◽  
External Pressure ◽  
Design Parameters ◽  
Collapse Strength ◽  
Parameters Uncertainty ◽  
Wide Range ◽  
Model Predictions ◽  
Strength Models

Abstract This paper assesses the uncertainty in the collapse strength of sandwich pipelines under external pressure predicted by various strength models in three categories based on interlayer adhesion conditions. First, the validity of the strength models is verified by comparing their predictions with sandwich pipeline collapse test data and the corresponding model uncertainty factors are derived. Then, a parametric analysis of deterministic collapse strength predictions by models is conducted, illustrating insights of models’ behaviour for a wide range of design configurations. Furthermore, the uncertainty among different model predictions is perceived at different configurations of outer and inner pipes and core thicknesses. A case study of a realistic sandwich pipeline is developed, and probabilistic models are defined to basic design parameters. Uncertainty propagation of models’ predictions is assessed by the Monte Carlo simulation method. Finally, the strength model predictions of sandwich pipelines are compared to that of an equivalent single walled pipe.

scholarly journals A Novel Approach to Measure the Hydraulic Capacitance of a Microfluidic Membrane Pump

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Chun-Hui Wu ◽  
Chia-Wei Chen ◽  
Long-Sheng Kuo ◽  
Ping-Hei Chen
Keyword(s):  
Linear Correlation ◽  
Experimental Results ◽  
Membrane Thickness ◽  
Membrane Pump ◽  
Novel Approach ◽  
Hydraulic Capacitance ◽  
Linear And Nonlinear ◽  
Center Deflection ◽  
Membrane Deflection ◽  
Good Agreement

A novel approach was proposed to measure the hydraulic capacitance of a microfluidic membrane pump. Membrane deflection equations were modified from various studies to propose six theoretical equations to estimate the hydraulic capacitance of a microfluidic membrane pump. Thus, measuring the center deflection of the membrane allows the corresponding pressure and hydraulic capacitance of the pump to be determined. This study also investigated how membrane thickness affected the Young’s modulus of a polydimethylsiloxane (PDMS) membrane. Based on the experimental results, a linear correlation was proposed to estimate the hydraulic capacitance. The measured hydraulic capacitance data and the proposed equations in the linear and nonlinear regions qualitatively exhibited good agreement.

scholarly journals Stability-Ranking of Crystalline Ice Polymorphs Using Density-Functional Theory

Crystals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Pralok K. Samanta ◽  
Christian J. Burnham ◽  
Niall J. English
Keyword(s):  
Density Functional Theory ◽  
Structure Prediction ◽  
Density Functional ◽  
Applied Pressure ◽  
External Pressure ◽  
Crystal Structure Prediction ◽  
Functional Theory ◽  
Stability Ranking ◽  
High Level ◽  
Basin Hopping

In this work, we consider low-enthalpy polymorphs of ice, predicted previously using a modified basin-hopping algorithm for crystal-structure prediction with the TIP4P empirical potential at three pressures (0, 4 and 8 kbar). We compare and (re)-rank the reported ice polymorphs in order of energetic stability, using high-level quantum-chemical calculations, primarily in the guise of sophisticated Density-Functional Theory (DFT) approaches. In the absence of applied pressure, ice Ih is predicted to be energetically more stable than ice Ic, and TIP4P-predicted results and ranking compare well with the results obtained from DFT calculations. However, perhaps not unexpectedly, the deviation between TIP4P- and DFT-calculated results increases with applied external pressure.

Knowledge Base Representation for Axiomatic Design Through Ontologies

2013 ◽  
Author(s):  
Zhuochen Shi ◽  
Gregory Mocko
Keyword(s):  
Axiomatic Design ◽  
Scientific Basis ◽  
Structure Design ◽  
Design Parameters ◽  
Formal Ontology ◽  
Functional Requirements ◽  
Car Seat ◽  
Design Structure ◽  
Design Activities ◽  
Multiple Groups

Axiomatic Design has been applied and developed as a tool, offering a scientific basis for design and improving design activities. Axiomatic Design has been used in various fields such as software system design, structure design, and product design. However, several challenges and limitations exist in Axiomatic Design including: the inconsistency in identifying design parameters, existence of coupled design, and multiple groups of functional requirements and design parameters. Aimed at using Axiomatic Design to generate conceptual solutions in engineering design while overcoming its limitations, a formal ontology is developed. The ontology defines functional requirements, design parameters, concepts, components and variables and their relationships. Axioms and rules of Axiomatic Design for the ontology are summarized. The Axiomatic Design ontology is applied to the design of a car seat as an example generating several concepts, and then compared and analyzed multiple groups of the concepts with the help of Axiomatic Design rules. More design ideas can be generated by combining detailed concepts as the higher level possible solutions.

Computational Study of a Target Fluidic Flowmeter

2010 ◽  
Author(s):  
Andrzej F. Nowakowski ◽  
Franck C. G. A. Nicolleau ◽  
S. M. Muztaba Salim
Keyword(s):  
Reynolds Number ◽  
Computational Study ◽  
Numerical Technique ◽  
Three Dimensional ◽  
Boundary Layer Separation ◽  
Structure Design ◽  
Design Parameters ◽  
Detached Eddy Simulation ◽  
Eddy Simulation ◽  
Wide Range

The computational studies on the flow structure, design and performance of a target fluidic flowmeter have been carried out. The computational challenge was to find a universal approach to study a wide range of flow regimes. To this end the Detached Eddy Simulation (DES) approach for unsteady flows was applied. The numerical technique enabled to accurately reproduced three dimensional flow structures in a target fluidic flowmeter. The signal analysis of the obtained results was conducted for a range of Reynolds numbers from laminar case up to 4000. The results show that a number of factors such as meter geometry and aspect ratio can influence the performance of the flow meter significantly. A minimum Reynolds number constraint for the measurements to be accurate was evaluated for various design parameters. The significance of using knife edges which influence boundary layer separation was also established. The experimental data, which were obtained for a prototype of flowmeter setup were used to validate numerical tools in the important area of low Reynolds number flows.

Effect of Purge Flow Swirl on Hot Gas Ingestion Into Turbine Rim Cavities

2013 ◽  
Author(s):  
M. B. Zlatinov ◽  
C. S. Tan ◽  
D. Little ◽  
M. Montgomery
Keyword(s):  
Mass Flow ◽  
Flow Model ◽  
External Pressure ◽  
Physical Principle ◽  
Design Parameters ◽  
Air Mass ◽  
Hot Gas ◽  
Flow Swirl ◽  
Purge Flow ◽  
Axial Turbines

Purge air, injected through seals in the hub of axial turbines, is necessary to prevent hot gas ingestion into endwall cavities, but generates losses by viscous interaction with the mainstream flow. Recent work has shown that for a given purge air mass flow rate, introducing swirl into the purge flow can reduce these losses. This paper investigates the effect of introducing such swirl on the ability of purge flow to prevent ingestion. In particular, it is observed that in the presence of the rotating external pressure non-uniformity due to a downstream blade row, swirled purge flow is much less effective in sealing a turbine disk rim cavity compared to non-swirled purge flow. This is reflected in higher purge air mass flow rates necessary to seal a given cavity, and that in turn diminishes the positive effect of pre-swirling purge flow in the first place. It is shown that this will occur whenever the circumferential pressure disturbance associated with the downstream rotating blades is the dominant driver for externally induced ingestion. It is reasoned that swirled purge flow moves with the rotating pressure non-uniformity and responds to it more readily than non-swirled purge flow, which sees the averaged effect of multiple blade passing events. A flow model based on this physical principle is developed, showing good agreement with computational results. The model yields an ingestion criterion with a parametric dependence on purge flow design parameters. The analysis is extended to an unsteady situation, whereby the effects of both stationary and rotating pressure non-uniformities, from vanes and blades respectively, are taken into account simultaneously. This unsteady flow model points to an optimal design space, in the context of minimizing purge flow losses while maintaining an appropriate margin with regard to hot gas ingestion.

Modeling of a New Crank-Less Rotary Heat Engine Concept for Solar Power Utilization

2018 ◽  
Author(s):  
Muhammad I. Rashad ◽  
Hend A. Faiad ◽  
Mahmoud Elzouka
Keyword(s):  
Degrees Of Freedom ◽  
Unit Cost ◽  
Heat Engine ◽  
Structure Design ◽  
Operating Conditions ◽  
Design Parameters ◽  
Working Fluid ◽  
Heat Engines ◽  
And Performance ◽  
Engine Concept

This paper presents the operating principle of a novel solar rotary crank-less heat engine. The proposed engine concept uses air as working fluid. The reciprocating motion is converted to a rotary motion by the mean of unbalanced mass and Coriolis effect, instead of a crank shaft. This facilitates the engine scaling and provides several degrees of freedom in terms of structure design and configuration. Unlike classical heat engines (i.e. Stirling), the proposed engine can be fixed to the ground which significantly reduce the generation unit cost. Firstly, the engine’s configuration is illustrated. Then, order analysis for the engine is carried out. The combined dynamics and thermal model is developed using ordinary differential equations which are then numerically solved by Simulink™. The resulting engine thermodynamics cycle is described. It incorporates the common thermodynamics processes (isobaric, isothermal, isochoric processes). Finally, the system behavior and performance are analyzed along with studying the effect of various design parameters on operating conditions such as engine speed, output power and efficiency.

Sign in / Sign up

Export Citation Format

Share Document