Spray Nozzle Research Articles

Mapping Reaction Pathways by In Situ Step Sweep Voltammetry Flow Electrochemical Mass Spectrometry.

A step sweep voltammetry (SSV) flow electrochemical (EC) mass spectrometry (MS) platform was developed for real-time and in situ mapping of EC reaction pathways. By integrating a flow EC cell into the pneumatic spray nozzle followed by atmospheric chemical ionization, this setup was capable of in situ MS monitoring of short-lived EC intermediates with enhanced sensitivity. This setup also realized precise measurement and control of the electrode potential during in situ EC-MS analysis, which can provide detailed information on the interplay of reaction pathways under different electrode potentials. Taking the EC reductive cross coupling of nitroarenes with arylboronic acids as an example, SSV-MS had identified 13 compounds among four reaction pathways. Among these, the electrode potential of active nitrene and cross coupling intermediates were measured for the first time and the structure of the nitroso coupling complex was also confirmed by MS. With the systematic measurement of electrode potential of the intermediates and products, SSV-MS had clearly mapped out the synergies and competitions between different reaction pathways, offering key insights for optimizing reaction conditions and investigating reaction mechanisms for EC research.

Innovative Microencapsulation of Polymyxin B for Enhanced Antimicrobial Efficacy via Coated Spray Drying.

This study aims to develop an innovative microencapsulation method for coated Polymyxin B, utilizing various polysaccharides such as hydroxypropyl β-cyclodextrin, alginate, and chitosan, implemented through a three-fluid nozzle (3FN) spray drying process. High-performance liquid chromatography (HPLC) analysis revealed that formulations with a high ratio of sugar cage, hydroxypropyl β-cyclodextrin (HPβCD), and sodium alginate (coded as ALGHCDHPLPM) resulted in a notable 16-fold increase in Polymyxin B recovery compared to chitosan microparticles. Morphological assessments using fluorescence labeling confirmed successful microparticle formation with core/shell structures. Alginate-based formulations exhibited distinct layers, while chitosan formulations showed uniform fluorescence throughout the microparticles. Focused beam reflectance and histograms from fluorescence microscopic measurements provided insights into physical size analysis, indicating consistent sizes of 6.8 ± 1.2 μm. Fourier-transform infrared (FTIR) spectra unveiled hydrogen bonding between Polymyxin B and other components within the microparticle structures. The drug release study showed sodium alginate's sustained release capability, reaching 26 ± 3% compared to 94 ± 3% from the free solution at the 24 h time point. Furthermore, the antimicrobial properties of the prepared microparticles against two Gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa, were investigated. The influence of various key excipients on the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values was evaluated. Results demonstrated effective bactericidal effects of ALGHCDHPLPM against both E. coli and P. aeruginosa. Additionally, the antibiofilm assay highlighted the potential efficacy of ALGHCDHPLPM against the biofilm viability of E. coli and P. aeruginosa, with concentrations ranging from 3.9 to 500 μg/m. This signifies a significant advancement in antimicrobial drug delivery systems, promising improved precision and efficacy in combating bacterial infections.

Horizontal Distribution of Liquid in an Over-Row Sprayer with a Secondary Air Blower

The aim of this study was to determine the influence of boom height above a crop stand and the spacing between nozzles and diffusers in an over-row sprayer on the uniformity of the horizontal spray distribution and the uniformity of the air velocity distribution. The experimental setup involved a prototype over-row sprayer equipped with a boom with a working width of 8 m and ten air diffusers with spray nozzles. Air diffusers were connected to one or two nozzles each, and they were installed on the boom at intervals of 60, 80, and 90 cm. Terminal airflow velocity at a canopy is determined by the height of a sprayer boom and the diffuser spacing, ranging from around 2 m s–1 to around 27 m s–1. The sprayer boom should be positioned at a height of 50 cm above a crop stand due to the difference between the minimum and maximum airflow velocities. The horizontal spray distribution was more uniform when the sprayer was equipped with hollow-cone nozzles instead of flat-fan nozzles; hollow-cone nozzles should be applied if the distance between nozzles needs to be adjusted to the row width and row spacing. The analyzed coefficients did not exceed 10% when the boom was positioned 50 cm above the crop stand and when the nozzles were spaced 80 cm apart, which suggests that, in this configuration, sprayers equipped with hollow-cone nozzles can also be applied to close-grown crops.

Development of a flexible electronic control unit for seamless integration of machine vision to CAN-enabled boom sprayers for spot application technology

This research work aimed to develop an Electronic Control Unit (ECU) to establish a flexible bridge between machine vision and boom sprayer to control nozzles individually for pesticide spot application based on the Controller Area Network (CAN). The ECU consisted of two electronic entities. The first used UART protocol to parse machine vision messages, detect pest areas, and convert them into binary arrays for nozzle activation. The second received these arrays and generated nozzle controller CAN frames which were broadcast to control the sprayer nozzles on the implement bus. The ECU was tested in four scenarios involving combinations of three machine vision systems and two nozzle systems. The lab tests confirmed, assuming accurate detections, the ECU successfully sent spray commands to all targets across various camera-nozzle ratios. However, at specific ratios (1:3 and 1:6), some nozzles opened in unintended patterns. In the fourth scenario conducted in the field at a 1:2 ratio, all targets were sprayed regardless of their dimensions and distribution in the field. In this scenario, the sprayer operated at speeds of 3.22 km/h, 6.44 km/h, and 9.66 km/h, demonstrating real-time spraying with 55° angled nozzles, where the ECU sent CAN messages every 10ms and issued 400 ms spray commands upon detection, achieving a minimum spray length of 345 mm per detection.

Comprehensive numerical and experimental analysis the impact of employing vortex generators on evaporative cooling process

Reduced energy usage is an important concern in vapor compression cooling systems, particularly in hot climates. These systems function poorly in hot weather and consume a lot of electricity. Evaporative condensers use the cooling impact of evaporation to facilitate the process of heat rejection and thereby increase energy efficiency. This work evaluates the impact of employing vortex generators on the performance of an evaporative condenser. The analysis is performed using a validated numerical model, a commercial CFD code. The proposed vortex generators are parallel plates with sinusoidal and zigzag patterns. Dry air enters a channel equipped with four vortex-generating plates and water spray. The incoming dry air cools due to the two-phase heat transfer during air contact with the sprayed water droplets, and the cooled air with the proper humidity level exits the channel. The investigated parameters include longitudinal nozzle position, inlet air flow rate, pitch, and the height of the vortex generator plates in two sinusoidal and zigzag modes and the obtained results are compared with the plain channel model. Greater inlet air velocity resulted in superior output temperatures and pressure drops, yet lower outlet relative humidity and water mass percentage. According to the findings, the air pressure drop and outlet dry temperature are raised by 152 % and 5 %, respectively, when the incoming air velocity is altered from 0.4 to 0.6 m. s−1 (50 % growth), and the nozzle position is moved from X = 1.35 m to X = 1.85 m (37.04 % change) from the channel entrance, while the relative humidity and water mass fraction are decreased by 19 % and 11 %, respectively. Additional research revealed that the vortex flow level is lower when the nozzle is positioned farther away from the plates, and the water spray's impact on lowering the local air temperature in vortex-flowing areas is more substantial when it is positioned closer to the plates. Furthermore, increasing wave height and pitch values of vortex generators result in a more extensive air pressure drop in the channel, and vice versa. This means that, at a fixed pitch, a higher plate wave height raises the amount of vortex flows. According to the findings, sinusoidal vortex plates have better efficiency than the zigzag ones, and in a channel equipped with water spray, the use of vortex plates before the water spray nozzles lowers the dry temperature at the outlet by about one °C compared to that of the plain channel.

Characterization and in vitro bioaccessability of optimized chia oil-Capsul-sodium alginate microparticles obtained by 3 nozzle spray-drying

The influence sodium alginate (SA) as an outer layer agent on bioaccessibility and matrix food release of purified chia oil (PCO) microencapsulated was investigated. PCO microparticles with Capsul were elaborated and optimized by response surface methodology (RSM), and then as an encapsulating agent and SA as an outer layer (PCO-Capsul/SA) were designed by mini spray-drying with 2 fluid nozzle (2-N) and 3 fluid nozzle (3-N). The optimal conditions obtained for PCO-Capsul system were: dryer inlet temperature of 114 °C and PCO:Capsul relation of 1:5.42. After the addition of SA out layer, PCO-Capsul/SA microparticles were subjected to in vitro static gastrointestinal digestion. PCO-Capsul/SA occurred mainly in the intestinal phase, showing the suitability of SA as an intestine-site release polymer. However, when PCO-Capsul/SA was incorporated into a yoghurt (Y), microparticles showed a significantly lower PCO matrix food release and bioaccessibility after in vitro digestion than PCO-Capsul-Y microparticles, due to their interaction between SA and Y. SA spray-dried by 3-N showed great potential for vehiculation of omega-3 rich oils in the future incorporation and develop of functional foods. Tweetable abstractThis research shows the role of the sodium alginate incorporation by 3 nozzle spray dryer when the design of an intestine-delivery food ingredient is intended.

Performance of Different Spray Nozzles in the Application of Defoliant on Cotton Plants (Gossypium hirsutum L.)

Defoliant spraying is an important link in the mechanized cotton harvest because adequate and uniform spraying can improve defoliation quality and reduce cotton trash content. In defoliant application, application volume and spraying technology are extremely important. In this study, the effectiveness of defoliant application to cotton plant that has come to harvest with two different application volumes and three different types of nozzles with a standard field crop sprayer was determined. Application rates were 250 and 400 L/ha and spraying nozzles were: (1) standard flat fan nozzle (TP8006), (2) air induction nozzle (AI 11002-VS) and (3) dual pattern nozzle (AI307003VP). A tracer (BSF) and defoliant were applied to mature cotton with approximately 60% open bolls and samplings for BSF deposition and spray coverage on cotton plant were done at two plant height (upper layer, lower layer) of plant. Before and after spraying, bolls open and leaves rate on cotton plants were calculated and filter papers were used to detect BSF deposition and water sensitive papers (WSP) were used to measure coverage rate of spraying methods used. Spectrofluorophotometer was used to detect the amount of tracer deposition on targets and an image process computer program was used to measure coverage rate on WSP. In analysis conclusions showed that air induction nozzle (AI 11002-VS), achieved better results than the dual pattern and standard flat fan nozzles in terms of higher depositions, coverages and leaf defoliations and boll opening rates. AI nozzles operating at 250 L/ha application rate provide the highest deposition and coverage rate on applications of defoliant, in addition, BSF as an indicator of the defoliant used reached on leaf beneath in merely this spray nozzle. After defoliation boll opining rate was 85-% on the 7th and 12th days after spraying and falling rate of leaves was 76-% at application rate of 250 L/ha with air induction (AI1102) nozzle.

Effect of nozzles on disease control with spraying fungicides in soybean crops

ABSTRACT The productivity of the soybean crop (Glycine max) can be limited by several factors, including diseases. In the integrated management of diseases, one of the strategies used is chemical control. The aim of this experiment was to evaluate the influence of spray nozzle types on the chemical control of fungal diseases in soybean plants. The experimental design was randomised blocks, with six treatments and four replications. The treatments consisted of control (without fungicide application on soybean plants) and application of fungicides with different spray nozzles: hollow cone jet, double flat jet, extended range flat jet, wide angle flat jet and air induction flat jet. The sprayer used was the backpack pressurised by carbon dioxide CO2. The experiment was installed in the Campos Gerais region (Paraná, Brazil); during three cropping seasons. The evaluated variables were incidence and severity, spray quality (covered area, droplet density, and relative amplitude) and yield components. It was concluded that the chemical control of fungal diseases in soybean plants reduced the proliferation of pathogens and losses in crop yield. There were significant changes in spraying quality in all analysed variables. There were no differences among the spray nozzle types regarding the analysis of incidence, severity and soybean yield components.

Experimental study on single-cylinder two-stroke piston expander based on in-cylinder spray heat transfer

Compressed air energy storage stands as a highly promising technology within the realm of energy retention. The piston expander finds applicability in smaller-scale compressed air energy storage systems. In compressed air energy storage systems, the expansion process is critical in energy discharge and significantly impacts overall performance. Isothermal expansion techniques are effective in enhancing the operational efficiency of piston expanders, in contrast to adiabatic expansion methodologies. Previous simulations by our research group show that the isothermal expansion model has a lower power output than the adiabatic expansion model due to its higher exhaust pressure. To further validate the accuracy of the simulation results, an experimental platform was constructed and the uncertainty of the experimental system as well as the measured data was evaluated. This study conducted experimental research using the single-variable method, focusing on different load conditions and spray parameters. The study findings indicate that the exhaust pressure during isothermal expansion consistently exceeds that of adiabatic expansion. The exhaust pressure of isothermal expansion increased by 3.85 % to 14.9 %. Under varying load conditions, the average rotational speed and output power of isothermal expansion were noted to be inferior to those of adiabatic expansion. Despite changes in nozzle diameter or spray temperature when the spray timing is set at 0°-180°, the average rotational speed and output power of isothermal expansion remain lower than that of adiabatic expansion. The average output power of isothermal expansion decreased by 1.29 % to 5.24 %. Nevertheless, if the spray timing is set between 0°-120°, the average output power of the isothermal expansion surpasses the adiabatic expansion with an improvement of 1.84 %.

Computational Fluid Dynamics Study on Bottom-Hole Multiphase Flow Fields Formed by Polycrystalline Diamond Compact Drill Bits in Foam Drilling

High-temperature geothermal wells frequently employ foam drilling fluids and Polycrystalline Diamond Compact (PDC) drill bits. Understanding the bottom-hole flow field of PDC drill bits in foam drilling is essential for accurately analyzing their hydraulic structure design. Based on computational fluid dynamics (CFD) and multiphase flow theory, this paper establishes a numerical simulation technique for gas-liquid-solid multiphase flow in foam drilling with PDC drill bits, combined with a qualitative and quantitative hydraulic structure evaluation method. This method is applied to simulate the bottom-hole flow field of a six-blade PDC drill bit. The results show that the flow velocity of the air phase in foam drilling fluid is generally higher than that of the water phase. Some blades’ cutting teeth exhibit poor cleaning and cooling effects, with individual cutting teeth showing signs of erosion damage and cuttings cross-flow between channels. To address these issues, optimizing the nozzle spray angle and channel design is necessary to improve hydraulic energy distribution, enhance drilling efficiency, and extend drill bit life. This study provides new ideas and methods for developing geothermal drilling technology in the numerical simulation of a gas-liquid-solid three-phase flow field. Additionally, the combined qualitative and quantitative evaluation method offers new insights and approaches for research and practice in drilling engineering.

Optimization of particle acceleration parameters of special cold spray nozzles via neural network and genetic algorithm

Optimization of particle acceleration parameters of special cold spray nozzles via neural network and genetic algorithm

基于PTO协议的变量喷雾系统设计与试验

The aim of this research is to address the issues of low precision in variable spraying within the existing farmland application system, whereby nozzles cannot be controlled independently and low pesticide utilisation is observed. A variable spraying system based on PTO protocol has been designed. The system comprises an STM32 microcontroller as the control core, including the host computer, multi-channel controller, electronic switch, and electromagnetic spray nozzle. The master control unit receives the spray amount set by the user and calculates the duty cycle of the corresponding nozzle, which is then sent to the multiplex controller in real time through CAN communication. The multiplex controller adjusts the on-off frequency and duty cycle of each electromagnetic nozzle in real time according to the duty cycle of the corresponding nozzle it receives, thus enabling the nozzles to be controlled independently. This study offers theoretical and technical support for the independent control of spray nozzles and the optimisation of pesticide utilisation for variable spray systems based on PTO protocols.

Effect of flash boiling on the spray characteristics of pressure swirl spray nozzles using liquid nitrogen

Effect of flash boiling on the spray characteristics of pressure swirl spray nozzles using liquid nitrogen

Segment-based Eulerian-Lagrangian transition method for flat nozzle spray atomization simulation

This paper presents a novel segment-based Eulerian-Lagrangian transition method for predicting the primary and secondary breakup behavior of a flat nozzle spray. It combines the Volume of Fluid (VOF) method for simulating liquid sheet disintegration and primary breakup with the Discrete Phase Model (DPM) method for secondary breakup. The VOF simulation predicts the varying thickness and local velocity characteristics of the liquid sheet from the center region to the edge region near the nozzle exit. Meanwhile, the proposed segment-based linear stability analysis in this study is capable of predicting the initial droplet variation resulting from primary breakup, considering the varying behavior of the liquid sheet from different regions. The simulation results match reasonably well with experimental data at both macroscopic and microscopic levels, effectively predicting the overall spray structure, mass flow rate, and droplet size variations across different regions with good accuracy. Both experimental and numerical data show that the Sauter mean diameter (SMD) values differ between the center and edge regions, with the edge region displaying larger droplets than the center region. This indicates that the segment-based approach is crucial for successfully predicting the spatial distributions of droplet size characteristics.

Fine-grained method for determining size and velocity distribution patterns of flat-fan nozzle-atomised droplets based on phase doppler interferometer

Pesticides are commonly applied by using agricultural nozzles to generate droplets during delivery process. Initial spray atomization characteristics including droplet size and velocity are important factors that affect the pesticide utilization rate. Exploring efficient methods for atomization measurement is helpful to deeply understanding nozzle sprays. In this study, droplet size and velocity of a flat-fan nozzle were measured with phase doppler interferometry (PDI), and sub-area statistics method was adopted to establish a fitting model for atomization characteristics analyse. The results demonstrated that the distribution patterns and value contrasts of droplet size and velocity in different sub-areas visually reflect the nozzle atomization characteristics under varying spray pressures. The quantized model of droplet size and velocity within spatial sub-areas of spray atomization revealed significant differences in droplet size and velocity at various positions within the atomization area. Near the edge of the initial atomization zone, droplet size increases while velocity exhibits a decreasing trend. Additionally, the coefficient of determination for the x-axis position within the atomization zone, in relation to droplet size and velocity, was above 90%. The PDI with the sub-area statistical method employed in this study offers a fine-grained approach for investigating nozzle atomization characteristics.

Spray performance simulation and experiment analysis of a greenhouse fixed-pipe twin-fluid cold fogger with different nozzle settings.

High-efficient pesticide application equipment for protected cultivation is scarce. In response, a fixed-pipe twin-fluid clod fogger (FTCF) was proposed as a potential solution. To investigate the optimal nozzle layout and spray performance, a computational fluid dynamics (CFD) model was used to study the airflow distribution and spray deposition of a FTCF with different nozzle settings using the Euler-Lagrange approach. Specifically, two piping configurations, middle-cross-inverted (MCI) and bilateral-malposed-opposite (BMO), were combined with three nozzle spacings (2 m, 3 m, 4 m) resulting in six nozzle settings. Additionally, a greenhouse spray trial was conducted to test the performance of FTCF with the selected nozzle settings and to validate the model. The simulation results revealed that MCI piping configuration exhibited a stronger airflow disturbance compared to BMO configuration, indicating a more significant air-guided effect in the MCI configuration. Combining this finding with the ground droplet distribution analysis of MCI piping configuration, it was observed that MCI-2 m had the lowest coefficient of variation (CV) for ground deposition (20.56%). Consequently, MCI-2 m was determined as the most optimal nozzle setting. Verification results demonstrated a high consistency between experimental and simulated spray deposition results. The FTCF system effectively generated a three-dimensional airflow field throughout the greenhouse environment. Furthermore, jet flow produced by FTCF disrupted the overall airflow pattern within the greenhouse space which facilitated droplet suspension and dispersion. This study provides valuable insights and innovative ideas for enhancing pesticide application technologies in protected cultivations. © 2024 Society of Chemical Industry.

Improving oral delivery of ciprofloxacin through in situ spray drying and acid counterions

This study explores the application of a novel three-fluid nozzle spray drying technique in formulating in situ ciprofloxacin (CFX) salts for improved oral drug delivery. The used key materials in the study include CFX combined with four different counterions: succinic acid (SA), glutaric acid (GA), adipic acid (AA), and pimelic acid (PA), alongside hydroxypropyl methylcellulose (HPMC) as a matrix agent. The process utilized a three-fluid nozzle spray drying technique to produce CFX salts directly with these acids during the process, creating three types of formulations: pure salts (SALT), solutions of drug and polymer (SOL), and nanoprecipitates of drug within a polymer matrix (SUS). Powder X-ray Diffraction (PXRD) and Scanning Electron Microscopy (SEM) analyses revealed that the formulations predominantly exhibited an amorphous structure with varied particle shapes and sizes. The dissolution profiles of CFX salts show a marked burst release within the initial 5 min, with CFX-GA leading at nearly double the release rate of CFX-AA, after which all formulations rapidly achieve over 90 % dissolution and maintain a stable release up to 30 min. This pattern was attributed to the interactions between the drug salts and HPMC, resulting in a sustained release of CFX. In vivo experiments with rabbits revealed a higher plasma concentration of CFX for CGAH-sus compared to CGAH-sol, highlighting the enhanced bioavailability of the SUS formulation. The amorphous nature of CGAH-sus, with ionization confirmed through Raman spectroscopy, facilitated efficient drug release and absorption in the gastrointestinal tract. This study illustrates the effectiveness of the three-fluid nozzle spray drying method in producing salts with varied physical properties and dissolution profiles, holding potential for advanced oral drug delivery systems.

Environmental performance of three innovative leather production processes using less chromium and water

Leather production contributes positively to economic developments but can create severe environmental impacts, due to the associated consumptions of water and chemicals. The substance of main concern is the basic chromium sulphate, widely used as tanning agent, which provides high-technical performance to the finished leather. This study quantifies the environmental sustainability of a conventional leather production process and those of three innovative processes, characterised by limited consumptions of chromium and water. Standardised life cycle assessments were implemented, with reference to the production chains starting from pickled skins until the production of two finished leathers (for goods and footwear), having the same technical and aesthetic characteristics of those from the conventional process. The innovative tanning processes adopt conventional rotating drums or substitute them with spray nozzles or aerosol rooms, and require a specific pre-treatment that includes de-pickling, drying and stabilisation of input skins. Tests at industrial scale (or at pilot scale for the solution with aerosol rooms) indicate that the new processes strongly reduce impacts in terms of Human toxicity-cancer, Ecotoxicity freshwater and Resource use-minerals and metals (up to 57 %, 29 % and 48 %, respectively) even though they imply an increase in terms of Climate Change (up to 51 %). Losses of chromium in wastewater and solid waste are reduced from >33 g/m2finished leather, for the conventional process, to about 8 g/m2finished leather, 5 g/m2finished leather, and 1 g/m2finished leather, for the innovative processes.The environmental sustainability of the proposed new processes increases from the solution with drums (and less water and chromium) to that utilising spray nozzles and aerosol rooms. A great improving can be obtained even just with the “simple” new drum solution, able to reduce the Human toxicity-cancer potential up to 53 % and Resource use-minerals and metals potential up to 42 %.

An algae-based polymer material as a pesticide adjuvant for mitigating off-target drift

Off-target pesticide drift from cropland is a major source of pesticide exposure to pollinating insects inhabiting crop and wildlands in the lower Mississippi Delta (LMD) in the USA. This study is aimed to develop a drift-reducing pesticide adjuvant that is less/nontoxic to honeybees. Ongoing toxicology experiments with two widely-used insecticides and sodium alginate (SA) pointed out reductions in honeybee mortality compared to an industry standard reference polyacrylamide (PAM). When used as an adjuvant to spray the same insecticides described above, SA did not interfere in killing the target pests. Therefore, SA has been tested as a drift-reducing pesticide adjuvant to protect honeybees. Spray experiments in the lab were carried out in four sets: (i) water only, (ii) water and adjuvant, (iii) water and pesticide, and (iv) water, pesticide and adjuvant. Each set contained 18 treatment combinations to cover the ranges in spray pressure (three), adjuvant dose (three), and spray nozzles (two). The droplet spectrum was analyzed using a P15 image analyzer. Diameters of 10 %, 50 % and 90 % volumes (DV10, DV50, and DV90), droplet velocity, standard deviation and relative span were measured. The drift reduction potential (DRP) of SA was analyzed by (i) dose, (ii) spray pressure, and (iii) nozzle type. The DRP of SA is compared to that of PAM. Additionally, three field experiments were carried out to analyze the efficiency of SA in reducing pesticide drift. The results from our experiments collectively indicate that SA has significant potential in mitigating drift as well as minimizing pesticide toxicity to honeybees.

Assessment of sensor-based automatic smart watering unit for paddy nurseries under Indian perspective

A sensor-based automatic watering unit was developed to irrigate the paddy seedling trays. The watering unit comprised six flat spray nozzles with a direct current (DC) water pump and flow sensor, and these were kept at the top of the conveyor frame, which was actuated by a DC water pump with a solenoid valve to drop the water in trays. The actuation of the DC solenoid valve was controlled by a limit switch fitted to the conveyor frame, which sensed the moving trays on the conveyor. The performance of the developed unit was evaluated, and process optimization was performed using the Inscribed Central Composite Design in Response Surface Methodology. The effect of main operating parameters- chain conveyor speed (0.123, 0.196, and 0.27 m/s), spray operating pressure (1.5, 3.0, and 4.5 kg/cm2), and spray height (10,30 and 50 cm) on the performance of the sensor-based automatic watering unit was studied in terms of the amount of water spray requirement and coefficient of water spray uniformity in trays. The responses of the unit at its optimal parameter operation (spray operating pressure 4.5 kg/cm2, spray height 10 cm, and chain conveyor speed 0.14 m/s) were found to be 1.31 L/tray as the amount of water spray requirement and 92.41 % as the coefficient of water spray uniformity of the unit. Hence, it can be an efficient substitute with significantly less power consumption 41 W with a higher working capacity of 780 trays/h for watering into the paddy tray nursery. The developed sensor-based automatic smart watering unit saves irrigation water per square area of 68.90 %, 76.13 %, and 82.31 % compared to existing drip, sprinkler, and flood irrigation methods in mat-type paddy nurseries. The developed sensor-based automatic smart watering unit saves the watering cost INR 11,567.16 (140.02 USD) per hectare, reducing cost by 63.7 % compared to manual watering in the mat-type nursery preparation. Thus, an automatic smart watering unit in a paddy tray nursery offers consistent and uniform watering from an Indian perspective, promoting uniform germination, crop growth, and establishment. It conserves water by ensuring the right amount of water is applied at the right time, avoiding overwatering or under-watering.