Ultrasonically Driven Cavitating Atomizer: Prototype Fabrication and Characterization

2009 ◽  
Author(s):  
Nelson K. Akafuah ◽  
Abraham J. Salazar ◽  
Kozo Saito ◽  
Vedanth Srinivasan
Keyword(s):  
Liquid Flow Rate ◽  
Injection Pressure ◽  
Working Fluid ◽  
Liquid Jet ◽  
New Device ◽  
Liquid Injection ◽  
Fabrication And Characterization ◽  
Pressure Modulation ◽  
Experimental Rig

A new device, ultrasonic cavitating atomizer (UCA), has been developed that uses ultrasonically driven cavitation to produce fine droplets. In the UCA the role of cavitation is explicitly configured to enhance the breakup of the liquid jet exiting the nozzle into fine droplets; the pressure modulation also assists the breakup process. The experimental study involves the fabrication of a prototype and the building of an experimental rig to test the prototype using water as the working fluid. The parameters tested include liquid injection pressure, horn tip frequency and liquid flow rate. The result shows improvement in the atomization of water with the application of ultrasonic cavitation.

Droplet Interaction in the Liquid Injection by Multiple Orifices in the Performance of a Venturi Scrubber

2008 ◽  
Vol 591-593 ◽  
pp. 896-901 ◽  
Author(s):  
Vádila Giovana Guerra ◽  
M.A.F. Daher ◽  
M.V. Rodrigues ◽  
José Antônio Silveira Gonçalves ◽  
José Renato Coury
Keyword(s):  
Size Distribution ◽  
High Speed ◽  
Liquid Flow Rate ◽  
Experimental Tests ◽  
Liquid Jet ◽  
Gas Velocity ◽  
Venturi Scrubber ◽  
Liquid Injection ◽  
Multiple Jets ◽  
Jet Penetration

The Venturi scrubber, equipment frequently used in the removal of particles from gases, is constituted basically by a duct with a convergent section followed by a constriction, or throat, and a divergent section. A liquid, usually injected in the throat, is atomized by the flowing air at high speed. The formed droplets act as collectors of particles from the gas. The size and the size distribution of the droplets inside the equipment are therefore of great importance in the equipment performance. In the present work, the liquid jet penetration is visualized and the study of the droplet formation in a rectangular Venturi is carried out. The liquid injection is made through multiple orifices and the interaction of multiple jets is taken into account. In the experimental tests, the gas velocity in the throat, the liquid flow rate and the number of orifices for liquid injection were varied. A Malvern Spraytec aerosol analyzer was used for measuring of the droplet size and size distribution. The results showed that the liquid jet penetration influences significantly the size of the formed droplet.

scholarly journals Development of a Piezo-Driven Liquid Jet Dispenser with Hinge-Lever Amplification Mechanism

Micromachines ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 117 ◽  
Author(s):  
Mojiz Abbas Trimzi ◽  
Young Bog Ham ◽  
Byeung Cheol An ◽  
Young Min Choi ◽  
Jung Ho Park ◽  
...  
Keyword(s):  
Performance Improvement ◽  
Adhesive Bonding ◽  
Piezoelectric Actuators ◽  
Working Fluid ◽  
Liquid Jet ◽  
Quick Response ◽  
Microelectronics Packaging ◽  
Compact Structure ◽  
Novel Device ◽  
Amplification Mechanism

Owing to the quick response, compact structure, high precision, huge blocking force generation, and ease of operation, piezoelectric actuators are urgently being adopted in the field of advanced dispensing for jetting performance improvement and fulfillment of precision requirements in microelectronics packaging, adhesive bonding, and miniaturization industry. This research focuses on the fundamental design and development of a piezo-electrically driven compact fluid dispenser using the principle of a class-one lever for amplification of needle displacement, and enhancement of application areas of the developed jet dispenser. Using fundamental lever principle, geometry-based modelling is carried out to fabricate a working prototype of a normally closed hinge-lever type dispenser. Preliminary experiments are carried out to witness the workability of the fabricated dispenser to deliver 100 dots of working fluid per second that will provide a novel device for dispensing of various fluids, and the proposed amplification mechanism suits various other piezoelectric applications as well.

Echocardiographic considerations during deployment of the Helex Septal Occluder for closure of atrial septal defects

2003 ◽  
Vol 13 (3) ◽  
pp. 290-298 ◽  
Author(s):  
Leo Lopez ◽  
Roque Ventura ◽  
Elizabeth M. Welch ◽  
David G. Nykanen ◽  
Evan M. Zahn
Keyword(s):  
Three Dimensional ◽  
Intracardiac Echocardiography ◽  
New Device ◽  
Septal Defects ◽  
Acoustic Interference ◽  
Atrial Septal Defects ◽  
Helex Septal Occluder ◽  
Interventional Catheterization

The Helex Septal Occluder is a new device used to close atrial septal defects via interventional catheterization. In order to study the role of echocardiography during its use, and to describe the morphologic variants of defects suitable for closure with this occluder, we evaluated all patients undergoing intended closure of an atrial septal defect with the Helex occluder. A combination of transthoracic, transesophageal, three-dimensional, and intracardiac echocardiography were used before, during, and after the procedure to characterize anatomy, assess candidacy for closure, guide the device during its deployment, and evaluate results. Among the 60 candidates included in the study, 11 were excluded because of transesophageal echocardiographic and/or catheterization data obtained in the laboratory. Attempts at closure were successful in 46 patients, and unsuccessful in 3. We successfully treated four types of defects. These were defects positioned centrally within the oval fossa with appreciable rims along the entire circumference of the defect, defects with deficient or absent segments of the rim, defects with aneurysm of the primary atrial septum, and defects with multiple fenestrations. Follow-up transthoracic echocardiograms taken at a median of 7 months demonstrated no residual defects in 21, trivial residual defects in 17, and small residual defects in 8 patients. In 20 patients, three-dimensional reconstructions were used to characterize the morphology of the defect and the position of the device. Because transesophageal echocardiography was often limited by acoustic interference from the device, intracardiac echocardiography was utilized in 3 cases to overcome this limitation.

Influence of Gate Material and Process on Junctionless FET Subthreshold Performance

2016 ◽  
Vol 6 (2) ◽  
pp. 895
Author(s):  
Munawar A Riyadi ◽  
Irawan D Sukawati ◽  
Teguh Prakoso ◽  
Darjat Darjat
Keyword(s):  
Recent Progress ◽  
Electronic Device ◽  
Threshold Value ◽  
The Other ◽  
Subthreshold Slope ◽  
New Device ◽  
Nano Scale ◽  
Device Processing ◽  
Alternative Materials

The recent progress of dimension scaling of electronic device into nano scale has motivated the invention of alternative materials and structures. One new device that shows great potential to prolong the scaling is junctionless FET (JLFET). In contrast to conventional MOSFETs, JLFET does not require steep junction for source and drain. The device processing directly influence the performance, therefore it is crucial to understand the role of gate processing in JLFET. This paper investigates the influence of gate material and process on subthreshold performance of junctionless FET, by comparing four sets of gate properties and process techniques. The result shows that in terms of subthreshold slope, JLFET approaches near ideal value of 60 mV/decade, which is superior than the SOI FET for similar doping rate. On the other hand, the threshold value shows different tendencies between those types of device.

Digital Control of Working Fluid Flow Rate for an OTEC Plant

1986 ◽  
Vol 108 (2) ◽  
pp. 111-116 ◽  
Author(s):  
M. Nakamura ◽  
N. Egashira ◽  
H. Uehara
Keyword(s):  
Adaptive Control ◽  
Fluid Flow ◽  
Control System ◽  
Control Theory ◽  
Digital Control ◽  
Working Fluid ◽  
Fluid Flow Rate ◽  
Control Performance ◽  
Digital Control System

The role of control in operating an OTEC plant efficiently is of great importance. This paper describes digital control of working fluid rate based on an adaptive control theory for the “Imari 2” OTEC plant at Saga University. Provisions have been made for linkage between the software of the adaptive control theory and the hardware of the OTEC plant. We can obtain satisfactory control performance using this digital control system.

High Speed Liquid Impact Onto Wetted Solid Surfaces

1994 ◽  
Vol 116 (2) ◽  
pp. 345-348 ◽  
Author(s):  
H. H. Shi ◽  
J. E. Field ◽  
C. S. J. Pickles
Keyword(s):  
Shock Wave ◽  
Liquid Layer ◽  
Solid Surface ◽  
High Speed ◽  
Shear Failure ◽  
Soda Lime ◽  
Liquid Jet ◽  
Soda Lime Glass ◽  
The Impact

The mechanics of impact by a high-speed liquid jet onto a solid surface covered by a liquid layer is described. After the liquid jet contacts the liquid layer, a shock wave is generated, which moves toward the solid surface. The shock wave is followed by the liquid jet penetrating through the layer. The influence of the liquid layer on the side jetting and stress waves is studied. Damage sites on soda-lime glass, PMMA (polymethylmethacrylate) and aluminium show the role of shear failure and cracking and provide evidence for analyzing the impact pressure on the wetted solids and the spatial pressure distribution. The liquid layer reduces the high edge impact pressures, which occur on dry targets. On wetted targets, the pressure is distributed more uniformly. Despite the cushioning effect of liquid layers, in some cases, a liquid can enhance material damage during impact due to penetration and stressing of surface cracks.

scholarly journals Utilization Waste Brine Water Separator for Binary Electric Energy Conversion in Geothermal Wells

2021 ◽  
Vol 16 (4) ◽  
pp. 411-420
Author(s):  
Herianto
Keyword(s):  
Heat Exchanger ◽  
Electric Energy ◽  
Thermodynamic Cycle ◽  
Geothermal Field ◽  
Working Fluid ◽  
Fluid Temperature ◽  
Binary Cycle ◽  
Water Separator ◽  
Geothermal Wells

Nowadays, geothermal is one of the most environmentally friendly energy that can replace the role of fossils energy by converting steam to electricity. Brine is one of the by-products of the production of geothermal wells that are generally not used or simply re-injected. In fact, brine can be converted into electricity using the binary cycle process. In binary cycle, brine from separator is used as a heater of working fluid and transform it into a vapor phase. The vapor will be used to turn turbines and generators to produce electricity. The working fluid selection in accordance with the heating fluid temperature becomes important because it results in optimization of the thermodynamic cycle. The temperature of the wellhead in the geothermal field will decrease 3% per year and reducing the heating fluid temperature in heat exchanger. So, in this paper intends to utilizes brine to heat the heat exchanger by using iso-butane, n-pentane, and iso-pentane because its critical temperature can be stable at 193℃ wellhead temperatures. From the results of predictions from brain 2 production well for 17 years with iso-butane in this binary cycle planning, can utilize waste brine water separator to converse electric energy to produce 4 MWh electricity.

Sign in / Sign up

Export Citation Format

Share Document