Piezoelectrically Actuated Microvalves for Micropropulsion Applications

2002 ◽  
Author(s):  
Eui-Hyeok Yang ◽  
Choonsup Lee
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
Flow Rate ◽  
Soap Solution ◽  
Major Elements ◽  
Differential Pressure ◽  
Valve Design ◽  
Valve Structure ◽  
Silicon Tethers ◽  
Piezoelectric Stack Actuator

This paper presents a piezoelectric microvalve technology with a high pressure handling capability for micropropulsion applications. The device is a normally closed valve fabricated mostly by the micromachining of silicon. The valve consists of a custom designed piezoelectric stack actuator bonded onto silicon valve components in a stainless steel housing. Major elements of the silicon valve design include narrow edge seating rings and tensile-stressed silicon tethers that contribute to the desired normally closed leak-tight operation. No leak has been detected from a soap solution test at differential pressures of 0∼500 psi for a normally closed valve structure, indicating a leak rate of 0.001sccm or lower has been achieved. Piezoelectric operation has been successfully demonstrated at a differential pressure of 500 psi. A flow rate of 20 sccm at 100 psi has been obtained at 50 V.

Development of Robust Microvavles for Compact Robust Pumps/Hydraulic Actuators

2007 ◽  
Vol 121-123 ◽  
pp. 1207-1210
Author(s):  
B. Li ◽  
Q. Chen
Keyword(s):  
High Pressure ◽  
Flow Rate ◽  
Pressure Support ◽  
Test Results ◽  
Valve Design ◽  
Standard Process ◽  
Flow Rates ◽  
Forward Flow ◽  
Large Flow

In situ UV-LIGA assembled robust micro check valves with large flow rates (>10 ml/s, displacement related), high-pressure support ability (>10 MPa) and high operational frequencies (>10 kHz) made of nano-structured nickel were presented in this paper. The microvalve consists of an array of 80 single micro valves to achieve the required flow rates. Test results show that the forward flow rate is about 19 ml/s under pressure of 90Psi. The backward flow rate is negligible. The reliability of the valve is ensured by the valve design and nanostructured nickel realized. The tested tensile strength of a nano structured nickel is about 1GPa. The strength of SU-8 is 50MPa, which is more than 50% higher that fabricated with a standard process.

Research on Flow Characteristics of Pulverized Coal in a High Pressure Blow Tank

2012 ◽  
Author(s):  
Wenhao Pu ◽  
Peng Lu ◽  
Chen Yue ◽  
Dong Han
Keyword(s):  
High Pressure ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Fluid Model ◽  
Particle Diameter ◽  
Flow Characteristics ◽  
Differential Pressure ◽  
Pulverized Coal ◽  
Solid Mass

In the present study, the flow characteristics of a top discharge blow tank at high pressure were investigated. Experiments on discharge properties of pulverized coal in dense-phase pneumatic conveying system with a high pressure blow tank were carried out. The influences of fluidizing velocity, pressurizing velocity, transporting differential pressure, sending pressure in the blow tank and pulverized coal diameter on the solid mass flow rate were studied. The experimental results indicated that the ratio of fluidizing velocity to pressurizing velocity was of great importance on the solid mass flow rate and there existed an optimum range. The solid mass flow rate increased as the transporting differential pressure and sending pressure increased. The increase of particle diameter led to the decrease of the solid mass flow rate. A model for determining the solid mass flow rate has been formulated using dimensional analysis. It was found that the calculation results were in good agreement with the experimental data. Finally, a kinetic–frictional model, which treated the kinetic and frictional stresses in an additive manner, was incorporated into the two fluid model based on the kinetic theory of granular flow to simulate the transient behaviors of the high pressure blow tank.

Pyrolysis of brown algae (Bifurcaria Bifurcata) in a stainless steel tubular reactor: From a review to a case study

2018 ◽  
Vol 14 (1) ◽  
pp. 31-60 ◽  
Author(s):  
M. Y. Guida ◽  
F. E. Laghchioua ◽  
A. Hannioui
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Flow Rate ◽  
Brown Algae ◽  
Tubular Reactor ◽  
Nitrogen Flow ◽  
Nitrogen Flow Rate ◽  
Bifurcaria Bifurcata ◽  
Bio Oil

This article deals with fast pyrolysis of brown algae, such as Bifurcaria Bifurcata at the range of temperature 300–800 °C in a stainless steel tubular reactor. After a literature review on algae and its importance in renewable sector, a case study was done on pyrolysis of brown algae especially, Bifurcaria Bifurcata. The aim was to experimentally investigate how the temperature, the particle size, the nitrogen flow rate (N2) and the heating rate affect bio-oil, bio-char and gaseous products. These parameters were varied in the ranges of 5–50 °C/min, below 0.2–1 mm and 20–200 mL. min–1, respectively. The maximum bio-oil yield of 41.3wt% was obtained at a pyrolysis temperature of 600 °C, particle size between 0.2–0.5 mm, nitrogen flow rate (N2) of 100 mL. min–1 and heating rate of 5 °C/min. Liquid product obtained under the most suitable and optimal condition was characterized by elemental analysis, 1H-NMR, FT-IR and GC-MS. The analysis of bio-oil showed that bio-oil from Bifurcaria Bifurcata could be a potential source of renewable fuel production and value added chemicals.

SANDVIK PRESSURFECT

Alloy Digest ◽  
2015 ◽  
Vol 64 (1) ◽  
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
Corrosion Resistance ◽  
Direct Injection ◽  
Heat Treating ◽  
Gasoline Direct Injection ◽  
Fuel System ◽  
Bend Strength ◽  
Low Carbon ◽  
Steel Company

Abstract Sandvik Pressurfect is an austenitic chromium-nickel stainless steel with low carbon content used for high-pressure gasoline direct injection (GDI) fuel system. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and bend strength. It also includes information on corrosion resistance as well as heat treating and machining. Filing Code: SS-1195. Producer or source: Sandvik Steel Company.

Study of fluid flow through a channel deformed by piezoelement

2018 ◽  
Vol 13 (3) ◽  
pp. 1-10 ◽  
Author(s):  
I.Sh. Nasibullayev ◽  
E.Sh Nasibullaeva ◽  
O.V. Darintsev
Keyword(s):  
Fluid Flow ◽  
Pressure Drop ◽  
Boundary Conditions ◽  
Flow Rate ◽  
Contact Surface ◽  
Piezoelectric Element ◽  
Neumann Boundary ◽  
Differential Pressure ◽  
Physical Parameters ◽  
Flow Through

The flow of a liquid through a tube deformed by a piezoelectric cell under a harmonic law is studied in this paper. Linear deformations are compared for the Dirichlet and Neumann boundary conditions on the contact surface of the tube and piezoelectric element. The flow of fluid through a deformed channel for two flow regimes is investigated: in a tube with one closed end due to deformation of the tube; for a tube with two open ends due to deformation of the tube and the differential pressure applied to the channel. The flow rate of the liquid is calculated as a function of the frequency of the deformations, the pressure drop and the physical parameters of the liquid.

Weldability of High-Strength Stainless Steel for High Pressure Gaseous Hydrogen Environments

2017 ◽  
Vol 86 (8) ◽  
pp. 555-558
Author(s):  
Kana JOTOKU ◽  
Jun NAKAMURA ◽  
Takahiro OSUKI ◽  
Hiroyuki HIRATA
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
High Strength ◽  
Gaseous Hydrogen

Effect of High Pressure Gaseous Hydrogen on the Tensile Properties of Four Types of Stainless Steels: Investigation of Materials Properties in High Pressure Gaseous Hydrogen—1

2007 ◽  
Author(s):  
Hideki Nakagawa
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
Hydrogen Embrittlement ◽  
Storage System ◽  
Gaseous Hydrogen ◽  
Fuel Cell Vehicle ◽  
Ductility Loss ◽  
Hydrogen Storage System ◽  
Type 316L ◽  
Pressure Hydrogen

Practical application of fuel cell vehicle has started in the world, and high-pressure hydrogen tanks are currently considered to be the mainstream hydrogen storage system for commercially implemented fuel cell vehicle. Application of metallic materials to the components of high-pressure hydrogen storage system: hydrogen tanks, valves, measuring instructions and so on, have been discussed. In this work, tensile properties of four types of stainless steels were evaluated in 45MPa (6527psig) and 75MPa (10878psig) high-pressure gaseous hydrogen at a slow strain rate of 3×10−6 s−1 at ambient temperature. Type 316L (UNS S31603) stainless steel hardly showed ductility loss in gaseous hydrogen, since it had stable austenitic structure. On the other hand, Type 304 (UNS S30400) metastable austenitic stainless steel showed remarkable ductility loss in gaseous hydrogen, which was caused by the hydrogen embrittlement of strain induced martensitic phase. Likewise, Type 205 (UNS S20500) nitrogen-strengthened austenitic stainless steel showed remarkable ductility loss in gaseous hydrogen, though it had stable austenitic structure in the same manner as Type 316L. The ductility loss of Type 205 was due to the hydrogen embrittlement of austenitic phase resulting from the formation of planar dislocation array. Furthermore, Type 329J4L (UNS S31260) duplex stainless steel showed extreme ductility loss in gaseous hydrogen, which was caused by the hydrogen embrittlement of ferritic phase.

scholarly journals Microstructure, phase composition and hardness evolution in 316L stainless steel processed by high-pressure torsion

2016 ◽  
Vol 657 ◽  
pp. 215-223 ◽  
Author(s):  
Jenő Gubicza ◽  
Moustafa El-Tahawy ◽  
Yi Huang ◽  
Hyelim Choi ◽  
Heeman Choe ◽  
...  
Keyword(s):  
High Pressure ◽  
Stainless Steel ◽  
Phase Composition ◽  
316L Stainless Steel ◽  
High Pressure Torsion

Magnetic Characterization of SUS316L Deformed by High Pressure Torsion

2011 ◽  
Vol 239-242 ◽  
pp. 1300-1303
Author(s):  
Hong Cai Wang ◽  
Minoru Umemoto ◽  
Innocent Shuro ◽  
Yoshikazu Todaka ◽  
Ho Hung Kuo
Keyword(s):  
Plastic Deformation ◽  
High Pressure ◽  
Stainless Steel ◽  
Phase Transformation ◽  
Austenitic Stainless Steel ◽  
Volume Fraction ◽  
High Pressure Torsion ◽  
Austenitic Matrix ◽  
Magnetic Characterization

SUS316L austenitic stainless steel was subjected to severe plastic deformation (SPD) by the method of high pressure torsion (HPT). From a fully austenitic matrix (γ), HPT resulted in phase transformation from g®a¢. The largest volume fraction of 70% a¢ was obtained at 0.2 revolutions per minute (rpm) while was limited to 3% at 5rpm. Pre-straining of g by HPT at 5rpm decreases the volume fraction of a¢ obtained by HPT at 0.2rpm. By HPT at 5rpm, a¢®g reverse transformation was observed for a¢ produced by HPT at 0.2rpm.

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