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 A Hybrid Taguchi-Regression Algorithm for a Fuel Injection Control System

Sensors ◽  
2021 ◽  
Vol 22 (1) ◽  
pp. 277
Author(s):  
Wen-Chang Tsai
Keyword(s):  
High Pressure ◽  
Control System ◽  
Fuel Injection ◽  
Direct Injection ◽  
Gasoline Direct Injection ◽  
Injection System ◽  
Fuel Injection System ◽  
Direct Injection Engine ◽  
Injection Quantity ◽  
Injection Control

The fuel injection system is one of the key components of an in-cylinder direct injection engine. Its performance directly affects the economy, power and emission of the engine. Previous research found that the Taguchi method can be used to optimize the fuel injection map and operation parameters of the injection system. The electronic control injector was able to steadily control the operation performance of a high-pressure fuel injection system, but its control was not accurate enough. This paper conducts an experimental analysis for the fuel injection quantity of DI injectors using the Taguchi-Regression approach, and provides a decision-making analysis to improve the design of electronic elements for the driving circuit. In order to develop a more stable and energy-saving driver, a functional experiment was carried out. The hybrid Taguchi-regression algorithm for injection quantity of a direct injection injector was examined to verify the feasibility of the proposed algorithm. This paper also introduces the development of a high-pressure fuel injection system and provides a new theoretical basis for optimizing the performance of an in-cylinder gasoline direct injection engine. Finally, a simulation study for the fuel injection control system was carried out under the environment of MATLAB/Simulink to validate the theoretical concepts.

Water in Diesel Emulsion Behavior in High-Pressure Direct Injection System

2019 ◽  
pp. 85-99
Author(s):  
A. Rashid A. Aziz ◽  
Mhadi A. Ismael ◽  
Morgan Heikal ◽  
Firmansyah ◽  
Ibrahim B. Dalha ◽  
...  
Keyword(s):  
High Pressure ◽  
Direct Injection ◽  
Injection System

An experimental study for effect factors of the roller tappet induced impact noise in high-pressure fuel system of GDi engine

2020 ◽  
Vol 234 (10-11) ◽  
pp. 2473-2484
Author(s):  
Hui-Min Shen ◽  
Pei Tang ◽  
Chong Lian ◽  
Liangliang Hu ◽  
Shuang Wei
Keyword(s):  
High Pressure ◽  
Direct Injection ◽  
Gasoline Direct Injection ◽  
Injection System ◽  
Effect Factors ◽  
Fuel Pump ◽  
Impact Noise ◽  
Transmission Part ◽  
The Time Domain ◽  
The Impact

With the wide application of gasoline direct injection system, its noise problem is becoming increasingly prominent under serious competitive environment. As the primary noise source of the engine in idle condition, the significant noise generated by the low-to-high pressure transmission part of high-pressure fuel pump becomes more and more serious. This paper focuses on the driving component of high-pressure fuel pump, the roller tappet, and experimentally studies effect factors of impact noise induced by it at engine idle. Both the impact occurrence time and position are analyzed from the combined vibration acceleration and crankshaft/camshaft rotation angle signals in the time domain according to the structure and kinematic mechanism of the roller tappet. The influences of the axial clearance between roller and tappet shell, the engine rotation speed and the lubrication conditions are investigated by experiments. The experimental results show that the lubrication is the primary factor for the roller tappet induced impact noise reduction. A significant improvement about 83% can be achieved under pressure lubrication.

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.

Simulations of methanol fueled locomotive engine using high pressure co-axial direct injection system

Fuel ◽  
2021 ◽  
Vol 295 ◽  
pp. 120231
Author(s):  
Dhananjay Kumar ◽  
Hardikk Valera ◽  
Anirudh Gautam ◽  
Avinash Kumar Agarwal
Keyword(s):  
High Pressure ◽  
Direct Injection ◽  
Injection System ◽  
Locomotive Engine

Evaluation of Mixing Uniformity for Inline Mixers by Image Processing

2020 ◽  
Vol 63 (2) ◽  
pp. 429-443
Author(s):  
Xiang Dai ◽  
Youlin Xu ◽  
Junyang Chen ◽  
Jiaqiang Zheng
Keyword(s):  
Image Processing ◽  
Principal Component ◽  
High Viscosity ◽  
New Method ◽  
Injection System ◽  
Flow Rates ◽  
Mixing Ratios ◽  
Carrier Flow ◽  
Extension Tube ◽  
Nozzle Injection

HighlightsFour inline mixers with different structures are designed and tested for DNIS applications.A new method for evaluating inline mixing uniformity by image processing is presented.While higher carrier flow rates cause better uniformity, changes due to higher mixing ratios are complicated.The multi-injection jet mixer has simplified structure and relatively satisfactory mixing efficacy.Abstract. Effective and specialized mixing devices that can achieve pesticide injection and inline mixing simultaneously are required to achieve better mixing efficacy in direct nozzle injection systems (DNISs), especially when high-viscosity pesticides are used. To evaluate the inline mixing efficacies of four inline mixers with different structures under various application conditions and to propose optimized structures for those inline mixers, a new method for evaluating uniformity based on image processing is presented. The results of experiments show that the proposed method is adequate for determining mixing uniformity. The mixing uniformity of each mixer increased with carrier flow rates (Q) ranging from 800 to 2,000 mL min-1, but the variations were less significant than those achieved by varying the mixing ratio (P) from 1:100 to 10:100. The mixing uniformity in the jet mixer (mixer A) clearly decreased with an increase in P at different values of Q because the pesticide gradually concentrated on one side of the detection tube. The layered mixer (mixer B) performed better than mixer A, especially at high P. The extension tube installed downstream of mixer B to improve uniformity was shorter than that of mixer A. Mixer C, whose structure was a combination of mixers A and B, had optimal mixing efficacy and the most complicated structure. The uniformity of the multi-injection jet mixer (mixer D) (Haverage = 12.46) obtained by simplifying mixer C was superior to that of mixers A (Haverage = 15.35) and B (Haverage = 14.65) but inferior to that of mixer C (Haverage = 4.08). With a relatively simple structure, mixer D may generally meet the uniformity requirements, thus resulting in advantages for practical use in DNISs, although further structural optimization of mixer D seems necessary. Keywords: Direct nozzle injection system, Image processing, Inline mixers, Mixing uniformity, Principal component analysis, Various application conditions.

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