Residues and Cleaning Effects of a Direct Nozzle Injection System for Pesticide Application

2011 ◽  
Author(s):  
Malte Doerpmund ◽  
Xiang Cai ◽  
Jiri Vondricka ◽  
Martin Walgenbach ◽  
Peter Schulze Lammers
Keyword(s):  
Injection System ◽  
Pesticide Application ◽  
Nozzle Injection

scholarly journals Development and Preliminary Evaluation of an Integrated Individual Nozzle Direct Injection and Carrier Flow Rate Control System for Pesticide Applications

2019 ◽  
Vol 62 (2) ◽  
pp. 505-514 ◽  
Author(s):  
Joe D. Luck ◽  
Scott A. Shearer ◽  
Michael P. Sama
Keyword(s):  
High Pressure ◽  
Control System ◽  
Direct Injection ◽  
Injection System ◽  
Preliminary Evaluation ◽  
Variable Flow ◽  
Carrier Flow ◽  
Duty Cycles ◽  
Nozzle Injection ◽  
Injection Frequency

Abstract. Direct injection systems for agricultural spray applications continue to present challenges in terms of commercialization and adoption by end users. Such systems have typically suffered from lag time and mixing uniformity issues, which have outweighed the potential benefits of keeping chemical and carrier separate or reducing improper tank-mixed concentration by eliminating operator measurements. The proposed system sought to combine high-pressure direct nozzle injection with an automated variable-flow nozzle to improve chemical mixing and response times. The specific objectives were to: (1) integrate a high-pressure direct nozzle injection system with variable-flow carrier control into a prototype for testing, (2) assess the chemical metering accuracy and proper mixing at different combinations of injection valve frequency and duty cycle along with chemical pressure, and (3) assess the ability of the control system to ensure proper chemical dilutions and concentrations in the nozzle effluent resulting from step changes in target application rates. Laboratory experiments were conducted using the combined system. Results of these experiments showed that the open-loop control of the injectors could provide a means of accurately metering the chemical concentrate into the carrier stream. Chemical injection rates could be achieved with an average error of 5.4% compared to the target rates. Injection at higher duty cycles resulted in less error in the chemical concentration predictions. Discrete Fourier transform analysis showed that the injection frequency was noticeable in the nozzle effluent when the injector was operated at 3.04 MPa and 5 Hz (particularly at lower duty cycles). Increasing the injection pressure and operating frequency to 5.87 MPa and 7 Hz, respectively, improved mixing, as the injection frequency component was no longer noticed in the effluent samples. The variable-flow nozzle was able to maintain appropriate carrier flow rates to achieve product label chemical concentrations. In one case, the maximum allowable concentrate was exceeded, although the nozzle was able to recover in 0.5 s. Steady-state errors ranged from 2.5% to 7.5% for chemical concentrations compared to the selected chemical to carrier ratio (0.03614). This test scenario represented an application rate of 4.68 L ha-1 with velocity increases from 4.0 to 7.1 m s-1 and decreases from 7.1 to 4.0 m s-1, which were typical of the example field application data. Keywords: Pesticides, Precision agriculture, Spraying equipment, Variable-rate application.

scholarly journals Rapid Custom Prototyping of Soft Poroelastic Biosensor for Simultaneous Epicardial Recording and Imaging

2020 ◽  
Author(s):  
Bongjoong Kim ◽  
Arvin Soepriatna ◽  
Woohyun Park ◽  
Abigail Cox ◽  
Haesoo Moon ◽  
...  
Keyword(s):  
Large Strain ◽  
Mechanical Strain ◽  
Injection System ◽  
In Vivo Evaluation ◽  
Electrical Hysteresis ◽  
Organ Systems ◽  
Nozzle Injection ◽  
Potential Clinical Utility ◽  
Living Tissues

Abstract The growing need for the implementation of stretchable biosensors in the human body and organ systems has driven a new rapid prototyping scheme through the direct ink writing (DIW) of multidimensional functional architectures in an arbitrary shape and size to meet the requirement of adapting the geometric nonlinearity of a specific biological site. Recent approaches involve the use of biocompatible viscoelastic inks that are dispensable through an automated nozzle injection system. However, their pragmatic application remains challenged in particular medical practices that demand long-term reliable recording under periodic large strain cycles, such as the cardiac cycle, due to their viscoelastic nature that produces both mechanical and electrical hysteresis. Herein, we report a new class of a poroelastic silicone composite that is adaptable for high-precision DIW of a custom-designed biosensor, which is exceptionally soft and insensitive to mechanical strain without generating significant hysteresis. The unique structural property of the composite material yields a robust and seamless coupling to living tissues, thereby enabling both high-fidelity recording of spatiotemporal electrophysiological activity and real-time ultrasound imaging for visual feedback. In vivo evaluation of a custom-fit biosensor in a murine acute myocardial infarction model demonstrates a potential clinical utility in the simultaneous intraoperative recording and imaging on the epicardial surface, which may guide a definitive surgical treatment.

102 Control of Surge in Centrifugal Compressor by Using a Nozzle Injection System

2018 ◽  
Vol 2018.53 (0) ◽  
pp. 3-4
Author(s):  
Tomoki NAKAJIMA ◽  
Ryosuke ATARASHI ◽  
Hoshio TSUJITA ◽  
Akira IWAKAMI ◽  
TAKAHIRO Bamba ◽  
...  
Keyword(s):  
Centrifugal Compressor ◽  
Injection System ◽  
Nozzle Injection

Assessing the cleanability of a direct nozzle injection system

2011 ◽  
Vol 110 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Malte Doerpmund ◽  
Xiang Cai ◽  
Martin Walgenbach ◽  
Jiri Vondricka ◽  
Peter Schulze Lammers
Keyword(s):  
Injection System ◽  
Nozzle Injection

scholarly journals Rapid custom prototyping of soft poroelastic biosensor for simultaneous epicardial recording and imaging

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bongjoong Kim ◽  
Arvin H. Soepriatna ◽  
Woohyun Park ◽  
Haesoo Moon ◽  
Abigail Cox ◽  
...  
Keyword(s):  
The Body ◽  
Injection System ◽  
Large Strains ◽  
Direct Writing ◽  
Electrical Hysteresis ◽  
Nozzle Injection ◽  
Potential Clinical Utility ◽  
Living Tissues ◽  
Surgical Treatments

AbstractThe growing need for the implementation of stretchable biosensors in the body has driven rapid prototyping schemes through the direct ink writing of multidimensional functional architectures. Recent approaches employ biocompatible inks that are dispensable through an automated nozzle injection system. However, their application in medical practices remains challenged in reliable recording due to their viscoelastic nature that yields mechanical and electrical hysteresis under periodic large strains. Herein, we report sponge-like poroelastic silicone composites adaptable for high-precision direct writing of custom-designed stretchable biosensors, which are soft and insensitive to strains. Their unique structural properties yield a robust coupling to living tissues, enabling high-fidelity recording of spatiotemporal electrophysiological activity and real-time ultrasound imaging for visual feedback. In vivo evaluations of custom-fit biosensors in a murine acute myocardial infarction model demonstrate a potential clinical utility in the simultaneous intraoperative recording and imaging on the epicardium, which may guide definitive surgical treatments.

scholarly journals Closed-Loop Control of Chemical Injection Rate for a Direct Nozzle Injection System

Sensors ◽  
2016 ◽  
Vol 16 (1) ◽  
pp. 127 ◽  
Author(s):  
Xiang Cai ◽  
Martin Walgenbach ◽  
Malte Doerpmond ◽  
Peter Schulze Lammers ◽  
Yurui Sun
Keyword(s):  
Closed Loop ◽  
Injection Rate ◽  
Injection System ◽  
Closed Loop Control ◽  
Loop Control ◽  
Nozzle Injection

126 Control of Surge in Centrifugal Compressor by Using a Nozzle Injection System : Influence of Nozzle Opening Width

2016 ◽  
Vol 2016.51 (0) ◽  
pp. 49-50
Author(s):  
Hideyuki YAMASE ◽  
Tomoki NAKAJIMA ◽  
Hoshio TSUJITA ◽  
Akira IWAKAMI ◽  
Taichi KIMURA
Keyword(s):  
Centrifugal Compressor ◽  
Injection System ◽  
Nozzle Injection ◽  
Nozzle Opening ◽  
Opening Width

Shock Event Analysis, Characteristic Considerations and Conservativeness Influence in High Pressure Injection System Cavitating Flow Simulations

Volume 1 ◽  
2004 ◽  
Author(s):  
Alessandro Ferrari ◽  
Michele Manno ◽  
Antonio Mittica
Keyword(s):  
High Pressure ◽  
Injection System ◽  
Event Analysis ◽  
Transient Flows ◽  
Compression Waves ◽  
Pressure Injection ◽  
Pressure Time ◽  
Nozzle Injection ◽  
Time Histories ◽  
High Pressure Injection

A comparison between conservative and nonconservative models has been carried out for evaluating the influence of conservativeness on predicting transient flows in presence of cavitation induced discontinuities inside high-pressure injection systems. Even if nonconservative models can assure satisfactory accuracy in the evaluation of the wave propagation phenomena, they introduce fictitious source terms in the discretized equations. Such terms are usually negligible, but can play a significant role when discontinuities in the flow properties occur, producing appreciable errors on the pressure wave speed estimation. An analysis based on fluid characteristics around both the rarefaction and compression wave fronts has been carried out, showing that cavitation desinence is a shock occurrence, leading to a transition from a supersonic to a subsonic flow. For a significant evaluation of conservative and nonconservative model performances a conventional pump-line-nozzle injection system was considered because the pipe flow presented interesting cases of cavitation-induced shocks. The validity of the conservative model is substantiated by the comparison between computed pressure time-histories and experimental results at two pipe locations. The Rankine-Hugoniot jump conditions have been usefully applied to the numerical results obtained by the conservative model in order to calculate the sound speed of the traveling compression waves in the presence of cavitation. A novel algorithm of general application to calculate the shock speed predicted by nonconservative models, which points out the contribution of the internal fictitious fluxes in the wrong estimation of the shock velocity, has been introduced and validated through its application to Burgers’ equation.

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