scholarly journals Evaluation of Different Internal Designs of Hydraulic Nozzles under an Accelerated Wear Test

2022 ◽  
Vol 12 (2) ◽  
pp. 889
Author(s):  
Marek Milanowski ◽  
Alaa Subr ◽  
Stanisław Parafiniuk
Keyword(s):  
Flow Rate ◽  
Coefficient Of Variation ◽  
Wear Test ◽  
International Organization ◽  
Pesticide Application ◽  
Application Process ◽  
Abrasive Material ◽  
Negative Effect ◽  
Spray Distribution ◽  
Resistance To Wear

The use of worn-out agricultural nozzles in pesticide application has a negative effect on the efficiency and cost of the application process. It also has an effect on environmental pollution due to an excessive amount of pesticide being applied when spraying with worn-out nozzles. In this paper, the resistance to wear of three different internal design hydraulic nozzles was ascertained. Changes in the flow rate and spray distribution as a result of this wear were also investigated. The wear test was done inside a closed system, and it was accelerated using an abrasive material to generate 100 h of wear. The tested nozzles were the Turbo TeeJet (TT)-twin chambered, Turbo Twinjet (TTj60)-dual outlet, and Drift Guard (DG)-pre-orifice. Wear rate, flow rate, and the virtual coefficient of variation (CVv) were measured at different wear intervals. The results showed that the TTj60 type was the most resistant to wear, followed by the TT type and DG. The latter two types showed an increase in the flow rate only in the first 45 h of wear. Virtual coefficient of variation (CVv) values were less than 10% after finishing the test (after 100 h of wear) for the three types of nozzles, which are acceptable values according to International Organization for Standardization (ISO) 16122-2, 2015.

Effects of the staggered blades on unsteady pressure pulsations and flow structures of a centrifugal pump

2021 ◽  
pp. 095765092098732
Author(s):  
Ning Zhang ◽  
Bo Gao ◽  
Chao Li ◽  
Dan Ni ◽  
Guoping Li
Keyword(s):  
Centrifugal Pump ◽  
Flow Rate ◽  
Pressure Pulsation ◽  
Second Harmonic ◽  
Simulation Method ◽  
Pump Efficiency ◽  
Pressure Amplitude ◽  
Pressure Pulsations ◽  
Unsteady Pressure ◽  
Negative Effect

Effects of the staggered blades on unsteady pressure pulsations of a centrifugal pump with a specific speed ns=147 are investigated by the numerical simulation method. The obtained results are compared with the original blades. To clarify the resulting effects, eight monitoring points are used to extract pressure signals at three typical working conditions, and component at the blade passing frequency fBPF is emphasized. Results show that the pump efficiency and head will be reduced by the staggered blades, and at the nominal flow rate, the reduction is about 1.5% from comparison with the original blades. For all the eight points, the staggered blades contribute to the reduction of pressure amplitudes at fBPF when the pump works at three flow rates. The averaged reduction is 15.5% at the nominal flow rate. However, the negative effect on the second harmonic of fBPF will be caused by the staggered blades, and the corresponding pressure amplitude will increase at 2fBPF. It means that the pressure pulsation energy will be redistributed among the discrete components in pressure spectrum by the staggered blades. From the TKE distribution, it is found that the TKE values on the blade pressure side will be significantly affected by the staggered blades.

scholarly journals Influence of working pressure and spray nozzle on the distribution of spray liquid in manual backpack sprayers

2019 ◽  
Vol 86 ◽  
Author(s):  
Alcides Marangoni Junior ◽  
Marcelo da Costa Ferreira
Keyword(s):  
Coefficient Of Variation ◽  
Spray Nozzle ◽  
Hollow Cone ◽  
Distribution Profile ◽  
Working Pressure ◽  
Spray Solution ◽  
Phytosanitary Treatment ◽  
Spray Distribution ◽  
Distribution Uniformity

ABSTRACT Manual backpack sprayers are widely used in rural properties in Brazil. However, studies that assess their working characteristics, especially spray tip models and working pressure conditions, are scarce. Thus, the aim of this study was to assess how much the working pressure and spray tips influence the distribution quality of phytosanitary spray solutions in manual backpack sprayers. Four spray nozzles (standard flat-fan Magnojet TP11002, turbo flat-fan TeeJet TT11002, hollow-cone TeeJet TXA8002, and disc-core) were assessed in a patternator table at 1, 2, 3, and 4 bar. Analyses of spray distribution profile were performed by symmetry and the coefficient of variation (CV) analysed by the Tukey’s test (p < 0.05). Spray tip models and working pressure influenced in more than 100% the distribution uniformity values of spray solution and in about 50% the useful range of the phytosanitary treatment. Among the models assessed in this study, the turbo flat-fan spray nozzle presents the best set of characteristics to be indicated for manual backpack sprayers aiming at field phytosanitary treatments.

scholarly journals Selected Constituent Yield Variation in the Smoke of Commercial Cigarette Brands on the Japanese Market

2017 ◽  
Vol 27 (8) ◽  
pp. 208-223
Author(s):  
Takatsugu Hyodo
Keyword(s):  
Carbon Monoxide ◽  
Confidence Intervals ◽  
Coefficient Of Variation ◽  
International Organization ◽  
Strongly Correlated ◽  
Japanese Market ◽  
Yield Variation ◽  
International Organization For Standardization ◽  
Cigarette Manufacturing ◽  
Health Canada

Summary This study focused on the variation in the yields of constituents in smoke from commercial cigarette brands available on the Japanese market. Nineteen commercial cigarette brands were sampled five times every two months from 2009 to 2010. The target constituents were benzo[a]-pyrene, 1,3-butadiene, benzene, formaldehyde, acetaldehyde, acrolein, N-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), carbon monoxide, “tar”, and nicotine. The results of this study showed that the coefficient of variation (CV) values varied greatly by brands, constituents, and smoking regimes. The yields of NNN and NNK in the smoke were strongly correlated to their yields in the tobacco filler blend for most brands. The yields of benzo[a]pyrene under the International Organization for Standardization (ISO) and the Health Canada Intense (HCI) smoking regimes and 1,3-butadiene under the HCI smoking regime were found to be influenced by the measurement. It was shown that factors for variation were highly varied among constituents. The grand mean of CV values for NNN and formaldehyde associated with cigarette manufacturing over ten months and measurement at the JT laboratory under the HCI smoking regimes were 17.1% and 6.6% respectively. The grand mean of CV values for NNN and formaldehyde associated with both cigarette manufacturing over ten months and measurement at different laboratories under the HCI smoking regimes were 23.7% and 22.9% respectively. This is due to the fact that formaldehyde showed the highest CV values for reproducibility among the constituents. Thus, in order to set realistic and robust confidence intervals, it is very important to take into account the variations associated with cigarette manufacturing and measurement within and between laboratories.

scholarly journals Effect of Pressure on the Uniformity of Nozzles Transverse Distribution and Mathematical Model Development

2017 ◽  
Vol 65 (2) ◽  
pp. 563-568 ◽  
Author(s):  
Vladimir Višacki ◽  
Aleksandar Sedlar ◽  
Rajko Bugarin ◽  
Jan Turan ◽  
Patrik Burg
Keyword(s):  
Mathematical Model ◽  
Coefficient Of Variation ◽  
Model Development ◽  
Pressure Change ◽  
Operating Pressure ◽  
Pesticide Application ◽  
Working Pressure ◽  
Transverse Distribution ◽  
Working Liquid

Timely and high-quality application of pesticides contributes to environmental protection, economical production and production of healthy food. The efficacy of pesticide application depends not only on the quality of pesticides but also the quality of the application. One of the factor that most influences the quality of applications, from the standpoint of mechanization, are nozzles. They working liquid applied on the surface the plant resulting in the same volume of pesticide is applied to the entire surface of the plants. To achieve this goal, nozzles must be performed uniform application of working liquid per unit area, or tractor sprayer working width. The variable factor in the application of pesticides may be nozzle and operating pressure. With increasing working pressure obtained smaller droplets. The paper presents test of three different nozzles. Each nozzle is characterized by a flat jet with an angle of 110° and a flow rate of 1.6 l∙min−1 at a pressure of 3 bar. Differ from each other are by the way of disintegration of the jet. Exactly this characteristic causes that with pressure change coming to changes in the uniformity of nozzles transverse distribution. So the best distribution has nozzle with a flat jet. The coefficient of variation is between roughly from 4 to 6 % at the pressure application of 2 to 4 bar. Obtained mathematical model that describes changes in the coefficient of variation depending on pressure applications can be a good basis for easy harmonization parameters in the pesticide application.

Influence of Albumin in the Microfluidic Synthesis of PEG-PLGA Nanoparticles

2019 ◽  
Vol 7 (6) ◽  
pp. 460-468 ◽  
Author(s):  
Bettina Poller ◽  
Gavin F. Painter ◽  
Greg F. Walker
Keyword(s):  
Particle Size ◽  
Aqueous Phase ◽  
Flow Rate ◽  
Coefficient Of Variation ◽  
Polymer Concentration ◽  
Plga Nanoparticles ◽  
Organic Polymer ◽  
Flow Rate Ratio ◽  
Aqueous Solvent ◽  
Average Size

Background: A key challenge in the manufacturing of polymeric colloids is producing nanoparticles with good batch-to-batch consistency. Objective: Develop a robust microfluidics method for the preparation of PEG-PLGA nanoparticles using dimethyl sulfoxide (DMSO) as the organic phase solvent for the encapsulation of DMSO soluble agents. Method: Microfluidic process parameters, total flow rate (10 mL/min), flow rate ratio (1:1) of the aqueous phase and the organic polymer solution, and polymer concentration (5 mg/ml). Polyvinyl alcohol (PVA) or human serum albumin (HSA) was included in the aqueous phase. Dynamic light scattering and transmission electron microscopy were used to investigate the size and morphology of particles. Results: PLGA nanoparticles made using DMSO with the aqueous solvent containing PVA (2%) had an average size of 60 nm while PLGA-PEG nanoparticles made with and without PVA (2%) had an average size of 70 and 100 nm, respectively. PLGA-PEG nanoparticles generated with or without PVA had a high batch-to-batch coefficient of variation for the particle size of 20% while for PLGA nanoparticles with PVA it was 4%. HSA added to the aqueous phase reduced the size and the zeta potential of PEG-PLGA nanoparticles as well the batch-to-batch coefficient of variation for particle size to < 5%. Nanoparticles were stable in solution and after lyophilized in the presence of sucrose. Conclusion: Albumin was involved in the self-assembly of PEG-PLGA nanoparticles altering the physicochemical properties of nanoparticles. Adding protein to the aqueous phase in the microfluidic fabrication process may be a valuable tool for tuning the properties of nanoparticles and improving batch-to-batch consistency.

Experimental Study on Spray Uniformity of Spraying Machinery

2013 ◽  
Vol 671-674 ◽  
pp. 1993-1997
Author(s):  
Yu Jing He ◽  
Heng Ming Hua ◽  
Xiang Fu Li ◽  
Jing Zhao Shi
Keyword(s):  
Experimental Study ◽  
Distribution Coefficient ◽  
Coefficient Of Variation ◽  
Influence Factors ◽  
Optimum Combination ◽  
Spray Distribution ◽  
Distribution Uniformity ◽  
Made In

Spray distribution uniformity is a very important performance of nozzle. This paper analyses the spray uniformity of the spraying machinery as well as the influence factors. Spray distribution coefficient of variation of nozzles varies with the different spray pressure, spray pressure and spacing. The nozzles of lechler ST made in German were tested to present the optimum spray height with different spray pressure and spray spacing through analyzing the trend of coefficient of variation varying with the different spray pressure, spray height and spray spacing. By the test, the greatest impact on spray uniformity is the pressure of the spray bar, followed by the height and the spacing of the spray bar. By analysis of the spray distribution coefficient of variation, we find the optimum combination of the spray pressure, spray height and spray spacing.

scholarly journals Beyond the flow rate: the importance of thermal range, flow intensity, and distribution for water-efficient showers

2019 ◽  
Vol 27 (5) ◽  
pp. 4640-4660
Author(s):  
Kemi Adeyeye ◽  
Kaiming She ◽  
Inês Meireles
Keyword(s):  
Flow Rate ◽  
Discharge Rate ◽  
Water Discharge ◽  
Laboratory Data ◽  
User Feedback ◽  
Physical Parameters ◽  
Thermal Range ◽  
Temperature Loss ◽  
Spray Distribution ◽  
Flow Intensity

AbstractStudies show that user behaviours have not necessarily changed, despite the prevalence of water-efficient products in the market. One reason is because the technical emphasis for delivering the water use efficiency of products has focused on reducing the flow rate. Therefore, this study was undertaken to examine the physical parameters that define the technical efficiency of showerheads against the experiential performance (and therefore the satisfaction with the showerheads). These parameters were measured in a controlled laboratory environment and the findings were triangulated against user feedback from in-home trials. Synergies between the laboratory data and user feedback were found. Notably, it was found that water spray intensity, distribution, and temperature loss all impact the quality of showering experience. These factors also influence shower duration—and thus the volume of water used in the shower. Significantly, these technical metrics affected the overall experiential performance of such products from the users’ perspective. Therefore, the design of water-efficient showerheads, in addition to delivering water discharge savings, should avoid poor spray distribution, intensity, and heat retention. The implications of the findings are that water efficiency labelling and product standards should extend beyond the emphasis on limiting the flow rates—typically to 9 l per min for showerheads. This study shows good merit for including the spray intensity (pressure), distribution, and degree of heat loss, in addition to the discharge rate, as part of the performance and efficiency considerations of showerheads.

scholarly journals Abrasion resistance of high early-strength concrete for rapid repair

2019 ◽  
Vol 289 ◽  
pp. 02002
Author(s):  
Nader Ghafoori ◽  
Matthew O. Maler ◽  
Meysam Najimi ◽  
Ariful Hasnat
Keyword(s):  
Compressive Strength ◽  
Abrasion Resistance ◽  
Wear Test ◽  
Cement Concrete ◽  
Rapid Repair ◽  
Strength Concrete ◽  
Type Iii ◽  
Resistance To Wear ◽  
Early Strength ◽  
Type V

This paper examines the abrasion resistance of high early-strength concrete developed for rapid repair of highways and bridge decks. The cement types chosen for this study included ASTM Type III, ASTM Type V, and Calcium Sulfoaluminate (CSA) cements. A cement content of 386 kg/m3 (650 lb/yd3) was maintained for all studied concretes. Test samples were tested after 24 hours and 28 days of curing in order to evaluate compressive strength and depth of wear. Test results revealed that the opening time to attain minimum required compressive strength for CSA cement concrete was one hour, whereas the values for Type V and Type III cement concretes were 8.5 and 6 hours, respectively. After 24 hours curing, CSA cement concrete displayed the highest strength, but lowest resistance to wear. The 28-day cured CSA cement concrete produced the highest strength and resistance to abrasion, while Type III cement concrete showed a similar strength, but lower resistance to wear, when compared to those of the Type V cement concrete.

scholarly journals Brackish water desalination using electrodialysis: predictive mass transfer and concentration distribution model along the electrodialyzer

2017 ◽  
Vol 77 (3) ◽  
pp. 597-607 ◽  
Author(s):  
Azadeh Ghorbani ◽  
Abbas Ghassemi
Keyword(s):  
Flow Rate ◽  
Concentration Distribution ◽  
Driving Forces ◽  
Water Desalination ◽  
Distribution Model ◽  
Navier Stokes ◽  
Feed Flow Rate ◽  
Feed Concentration ◽  
Ion Removal ◽  
Negative Effect

Abstract This study employs theory and experimental data from a laboratory-scale electrodialyzer to predict sodium chloride (NaCl) mass transport and concentration distribution along the electrodialyzer as a function of feed concentration, feed flow rate, applied voltage, and pressure. Moreover, a model was developed to predict the ion removal as a function of driving forces through solving the complete Navier–Stokes, continuity, and steady state Nernst–Planck equations by the finite difference numerical method. The findings of the experiments confirmed that concentration distributions are nonlinear along both the dilute and concentrate compartments. The results also demonstrated that increases in pressure and feed flow rate have a negative effect on salt removal, linear and nonlinear for pressure and flow rate, respectively. In the investigated ranges, higher voltage increased salt removal at a constant feed concentration.

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