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Study on the coupling calculation method for the launch dynamics of a self-propelled artillery multibody system considering engraving process
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作者 Shujun Zhang Xiaoting Rui +1 位作者 Hailong Yu Xiaoli Dong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期67-85,共19页
The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational eff... The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational efficiency,and imprecise analyses of system dynamic responses found in the dynamics research of intricate multi-rigid-flexible body systems,such as self-propelled artillery.This advancement aims to enhance the firing accuracy and launch safety of self-propelled artillery.Recognizing the shortfall of overlooking the band engraving process in existing theories,this study introduces a novel coupling calculation methodology for the launch dynamics of a self-propelled artillery multibody system.This method leverages the ABAQUS subroutine interface VUAMP to compute the dynamic response of the projectile and barrel during the launch process of large-caliber self-propelled artillery.Additionally,it examines the changes in projectile resistance and band deformation in relation to projectile motion throughout the band engraving process.Comparative analysis of the computational outcomes with experimental data evidences that the proposed method offers a more precise depiction of the launch process of self-propelled artillery,thereby enhancing the accuracy of launch dynamics calculations for self-propelled artillery. 展开更多
关键词 self-propelled artillery Engraving process Multibody system dynamics Launch dynamics
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Relationship between self-propelled velocity and Brownian motion for spherical and ellipsoid particles
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作者 Jingwen Wang Ming Xu Deming Nie 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期305-311,共7页
The Brownian motion of spherical and ellipsoidal self-propelled particles was simulated without considering the effect of inertia and using the Langevin equation and the diffusion coefficient of ellipsoidal particles ... The Brownian motion of spherical and ellipsoidal self-propelled particles was simulated without considering the effect of inertia and using the Langevin equation and the diffusion coefficient of ellipsoidal particles derived by Perrin.The P´eclet number(Pe)was introduced to measure the relative strengths of self-propelled and Brownian motions.We found that the motion state of spherical and ellipsoid self-propelled particles changed significantly under the influence of Brownian motion.For spherical particles,there were three primary states of motion:1)when Pe<30,the particles were still significantly affected by Brownian motion;2)when Pe>30,the self-propelled velocities of the particles were increasing;and 3)when Pe>100,the particles were completely controlled by the self-propelled velocities and the Brownian motion was suppressed.In the simulation of the ellipsoidal self-propelled particles,we found that the larger the aspect ratio of the particles,the more susceptible they were to the influence of Brownian motion.In addition,the value interval of Pe depended on the aspect ratio.Finally,we found that the directional motion ability of the ellipsoidal self-propelled particles was much weaker than that of the spherical self-propelled particles. 展开更多
关键词 Brown motion self-propelled particle orientation movement
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Self-propelled Leidenfrost droplets on femtosecond-laser-induced surface with periodic hydrophobicity gradient
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作者 Bohong Li Lan Jiang +2 位作者 Xiaowei Li Zhipeng Wang Peng Yi 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期502-509,共8页
The controllable transfer of droplets on the surface of objects has a wide application prospect in the fields of microfluidic devices,fog collection and so on.The Leidenfrost effect can be utilized to significantly re... The controllable transfer of droplets on the surface of objects has a wide application prospect in the fields of microfluidic devices,fog collection and so on.The Leidenfrost effect can be utilized to significantly reduce motion resistance.However,the use of 3D structures limits the widespread application of self-propulsion based on Leidenfrost droplets in microelectromechanical system.To manipulate Leidenfrost droplets,it is necessary to create 2D or quasi-2D geometries.In this study,femtosecond laser is applied to fabricate a surface with periodic hydrophobicity gradient(SPHG),enabling directional self-propulsion of Leidenfrost droplets.Flow field analysis within the Leidenfrost droplets reveals that the vapor layer between the droplets and the hot surface can be modulated by the SPHG,resulting in directional propulsion of the inner gas.The viscous force between the gas and liquid then drives the droplet to move. 展开更多
关键词 self-propelLED Leidenfrost droplets periodic hydrophobicity gradient femtosecond laser fabrication
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Passive particles driven by self-propelled particle:The wake effect
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作者 郑凯选 汪静文 +1 位作者 王世锋 聂德明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期500-507,共8页
This work focuses on numerically studying hydrodynamic interaction between a passive particle and a self-propelled particle,termed a squirmer,by using a two-dimensional lattice Boltzmann method(LBM).It is found that t... This work focuses on numerically studying hydrodynamic interaction between a passive particle and a self-propelled particle,termed a squirmer,by using a two-dimensional lattice Boltzmann method(LBM).It is found that the squirmer can capture a passive particle and propel it simultaneously,provided the passive particle is situated within the squirmer's wake.Our research shows that the critical capture distance,which determines whether the particle is captured,primarily depends on the intensity of the squirmer's dipolarity.The stronger dipolarity of squirmer results in an increased critical capture distance.Conversely,the Reynolds number is found to have minimal influence on this interaction.Interestingly,the passive particle,when driven by the squirmer's wake,contributes to a reduction in the squirmer's drag.This results in a mutual acceleration for both particles.Our findings can provide valuable perspectives for formulating the principles of reducing the drag of micro-swimmers and help to achieve the goal of using micro-swimmers to transport goods without physical tethers. 展开更多
关键词 lattice Boltzmann method(LBM) self-propelled particles particle-laden flow
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Application of Self-propelled Boom Sprayers for Control of Rice Insects and Diseases 被引量:1
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作者 龚艳 于林惠 +3 位作者 张晓 王果 陈伟 陈晓 《Agricultural Science & Technology》 CAS 2016年第7期1667-1670,共4页
Comparisons were performed between self-propelled boom sprayer and traditional mechanis, such as knapsack sprayer and sprayer-duster, stretcher-type powered sprayer, as well as single rotor unmanned sprayer and multi-... Comparisons were performed between self-propelled boom sprayer and traditional mechanis, such as knapsack sprayer and sprayer-duster, stretcher-type powered sprayer, as well as single rotor unmanned sprayer and multi-rotor un- manned sprayer. The effects on rice injury, lodging, and rehabilitation were conclud- ed and drug uniform distribution, sedimentation and prevention effects were ana- lyzed. The results showed that the self-propelled boom sprayer is characterized by high degree of automation, convenient operation, high adaptability, and high work efficiency. What's more, the sprayed fog quality is better, and fog distribution is more uniform. During the work process, fog loss would be diminished substantially, improving work efficiency and cutting down drug and water. It is notable that the underpart of the sprayer can be widely applied to plant protection in large-scale ar- eas in Jiangsu Province, significantly advancing whole-process mechanization of rice production. 展开更多
关键词 RICE self-propelLED SPRAYERS Insect and disease control Deposition distribution
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Where is the rudder of a fish?:the mechanism of swimming and control of self-propelled fish school 被引量:14
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作者 Chuijie Wu Liang Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第1期45-65,共21页
Numerical simulation and control of self- propelled swimming of two- and three-dimensional biomimetic fish school in a viscous flow are investigated. With a parallel computational fluid dynamics package for the two- a... Numerical simulation and control of self- propelled swimming of two- and three-dimensional biomimetic fish school in a viscous flow are investigated. With a parallel computational fluid dynamics package for the two- and three-dimensional moving boundary problem, which combines the adaptive multi-grid finite volume method and the methods of immersed boundary and volume of fluid, it is found that due to the interactions of vortices in the wakes, without proper control, a fish school swim with a given flap- ping rule can not keep the fixed shape of a queue. In order to understand the secret of fish swimming, a new feedback con- trol strategy of fish motion is proposed for the first time, i,e., the locomotion speed is adjusted by the flapping frequency of the caudal, and the direction of swimming is controlled by the swinging of the head of a fish. Results show that with this feedback control strategy, a fish school can keep the good order of a queue in cruising, turning or swimming around circles. This new control strategy, which separates the speed control and direction control, is important in the construction of biomimetic robot fish, with which it greatly simplifies the control devices of a biomimetic robot fish. 展开更多
关键词 self-propelled swimming Feedback controlstrategy of fish swimming ~ Direction control - Locomotionspeed control Three-dimensional biomimetic fish
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Comparison of Microbubble and Air Layer Injection with Porous Media for Drag Reduction on a Self-propelled Barge Ship Model 被引量:3
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作者 Yanuar Kurniawan T.Waskito +2 位作者 Sigit Y.Pratama Bagus D.Candra Bilmantasya A.Rahmat 《Journal of Marine Science and Application》 CSCD 2018年第2期165-172,共8页
Ship resistance issues are related to fuel economy,speed,and cost efficiency.Air lubrication is a promising technique for lowering hull frictional resistance as it is supposed to modify the energy in the turbulent bou... Ship resistance issues are related to fuel economy,speed,and cost efficiency.Air lubrication is a promising technique for lowering hull frictional resistance as it is supposed to modify the energy in the turbulent boundary layer and thereby reduce hull friction.In this paper,the objective is to identify the optimum type of air lubrication using microbubble drag reduction(MBDR)and air layer drag reduction(ALDR)techniques to reduce the resistance of a 56-m Indonesian self-propelled barge(SPB).A model with the following dimensions was constructed:length L=2000 mm,breadth B=521.60 mm,and draft T=52.50 mm.The ship model was towed using standard towing tank experimental parameters.The speed was varied over the Froude number range 0.11–0.31.The air layer flow rate was varied at 80,85,and 90 standard liters per minute(SLPM)and the microbubble injection coefficient over the range 0.20–0.60.The results show that the ship model using the air layer had the highest drag reduction up to a maximum of 90%.Based on the characteristics of the SPB,which operates at low speed,the optimum air lubrication type to reduce resistance in this instance is ALDR. 展开更多
关键词 self-propelLED BARGE Ship resistance AIR lubrication MICROBUBBLE drag REDUCTION AIR layer drag REDUCTION
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Classifying wakes produced by self-propelled fish-like swimmers using neural networks 被引量:5
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作者 Binglin Li Xiang Zhang Xing Zhang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2020年第3期149-154,共6页
We consider the classification of wake structures produced by self-propelled fish-like swimmers based on local measurements of flow variables.This problem is inspired by the extraordinary capability of animal swimmers... We consider the classification of wake structures produced by self-propelled fish-like swimmers based on local measurements of flow variables.This problem is inspired by the extraordinary capability of animal swimmers in perceiving their hydrodynamic environments under dark condition.We train different neural networks to classify wake structures by using the streamwise velocity component,the crosswise velocity component,the vorticity and the combination of three flow variables,respectively.It is found that the neural networks trained using the two velocity components perform well in identifying the wake types,whereas the neural network trained using the vorticity suffers from a high rate of misclassification.When the neural network is trained using the combination of all three flow variables,a remarkably high accuracy in wake classification can be achieved.The results of this study can be helpful to the design of flow sensory systems in robotic underwater vehicles. 展开更多
关键词 Flow sensing Machine learning Wake classification self-propelled swimming Fluid-structure interaction
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A comparative study of the self-propelled jumping capabilities of coalesced droplets on RTV surfaces and superhydrophobic surfaces 被引量:2
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作者 Sheng-Wu Wang Lu Peng +1 位作者 Jun-Wu Chen Lee Li 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期409-416,共8页
Understanding the mechanism of coalescence-induced self-propelled jumping behavior provides distinct insights in designing and optimizing functional coatings with self-cleaning and anti-icing properties.However,to dat... Understanding the mechanism of coalescence-induced self-propelled jumping behavior provides distinct insights in designing and optimizing functional coatings with self-cleaning and anti-icing properties.However,to date self-propelled jumping phenomenon has only been observed and studied on superhydrophobic surfaces,other than those hydrophobic surfaces with weaker but fairish water-repellency,for instance,vulcanized silicon rubber(RTV) coatings.In this work,from the perspective of thermodynamic-based energy balance aspect,the reason that self-propelled jumping phenomenon does not happen on RTV coatings is studied.The apparent contact angles of droplets on RTV coatings can be less than the theoretical critical values therefore cannot promise energy surplus for the coalesced droplets onside.Besides,on RTV and superhydrophobic surfaces,the droplet-size dependent variation characteristics of the energy leftover from the coalescence process are opposite.For the droplets coalescing on RTV coatings,the magnitudes of energy dissipations are more sensitive to the increase in droplet size,compared to that of released surface energy.While for superhydrophobic coatings,the energy generated during the coalescence process can be more sensitive than the dissipations to the change in droplet size. 展开更多
关键词 self-propelled jumping vulcanized silicon rubber(RTV) SUPERHYDROPHOBICITY SELF-CLEANING
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An Operational Modal Analysis Experimental Technique for Self-propelled Gun 被引量:1
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作者 王宝元 刘朋科 +3 位作者 衡刚 周发明 杨东 李明涛 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第2期96-99,共4页
The experimental modal analysis of the selected self-propelled gun was completed to obtain its modal frequency distribution and modes by using an operational modal analysis experimental technique.The result obtained b... The experimental modal analysis of the selected self-propelled gun was completed to obtain its modal frequency distribution and modes by using an operational modal analysis experimental technique.The result obtained by the method was compared with that obtained by the traditional method.It indicates that the two results are in good agreement. 展开更多
关键词 MECHANICS self-propelled gun operational modal EXPERIMENT ambient excitation
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Dynamics of a self-propelled particle under different driving modes in a channel flow
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作者 Zhenyu Ouyang Jianzhong Lin Xiaoke Ku 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期260-266,共7页
In this paper, a model that combines the lattice Boltzmann method with the singularity distribution method is proposed to simulate a self-propelled particle swimming(exhibiting translation and rotation) in a channel... In this paper, a model that combines the lattice Boltzmann method with the singularity distribution method is proposed to simulate a self-propelled particle swimming(exhibiting translation and rotation) in a channel flow. The results show that the velocity distribution for a self-propelled particle swimming deviates from a Maxwellian distribution and exhibits highvelocity tails. The influence of an eccentric potential doublet on the translation velocity of the particle is significant. The velocity decay process can be described using a double exponential model form. No large differences in the velocity distribution were observed for different translation Reynolds numbers, rotation Reynolds numbers, or regular intervals. 展开更多
关键词 lattice Boltzmann method singularity distribution method self-propelled particle driving modes
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Traction Potential Analysis of Self-Propelled Seafloor Trencher Based on Mechanical Measurements in Bentonite Soil
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作者 Meng Wang Xuyang Wang +1 位作者 Yuanhong Sun Zhimin Gu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第1期71-80,共10页
Shear stress-displacement relationship model of soil is very important to predict the tractive performance of tracked vehicle. Most shear stress-displacement models were proposed for terrestrial field.However,they are... Shear stress-displacement relationship model of soil is very important to predict the tractive performance of tracked vehicle. Most shear stress-displacement models were proposed for terrestrial field.However,they are not suit for soft seafloor with flow surface and high water content. Based on comprehensive analysis of seafloor soil shear deformation and track segment shear tests,a new empirical model of shear stressdisplacement relationship for saturated soft-plastic soil(SSP model) was proposed. To validate the SSP model and evaluate potential tractive force of self-propelled seafloor trencher,a test platform,where track segment shear test and drawbar pull test can be performed in seafloor soil substitute(bentonite water mixture),was built. Series of shear tests were carried out. Test results show that the SSP model can describe the mechanical behavior of track segment in seafloor soil substitute with good approximation. Through analyzing the main external forces,including environmental loads from seafloor soil and sea current applied to seafloor tracked trencher during the trenching process in a straight line,drawbar pull analysis model was deduced with the SSP model. A scale test model of seafloor tracked trencher was built,and the verification tests for drawbar pull analysis model were designed and carried out. Results of verification tests indicate that the drawbar pull analysis model was feasible and effective. The drawbar pull tests also indicated that the SSP model is valid from another side. 展开更多
关键词 shear stress-displacement relationship SSP model tractive performance drawbar pull self-propelled seafloor trencher
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Effect of the structure of backward orifices on thejet performance of self-propelled nozzles
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作者 Bi-Wei Fu Si Zhang Shao-Hu Liu 《Petroleum Science》 SCIE CAS CSCD 2021年第1期245-258,共14页
Self-propelled nozzle is a critical component of the radial jet drilling technology.Its backward orifice structure has a crucial influence on the propulsive force and the drilling performance.To improve the working pe... Self-propelled nozzle is a critical component of the radial jet drilling technology.Its backward orifice structure has a crucial influence on the propulsive force and the drilling performance.To improve the working performance of the nozzle,the numerical simulation model is built and verified by the experimental results of propulsive force.Then the theoretical model of the energy efficiency and energy coefficient of the nozzle is built to reveal the influence of the structural parameters on the jet performance of the nozzle.The results show that the energy efficiency and energy coefficient of the backward orifice increase first and then decrease with the angle increases.The energy coefficient of forward orifice is almost constant with the angle increases.With the increase in the number and diameter,energy efficiency and energy coefficient of the forward orifice gradually decrease,but the backward orifice energy coefficient first increases and then decreases.Finally,it is obtained that the nozzle has better jet performance when the angle of backward orifice is 30°,the number of backward orifice is 6,and the value range of diameter is 2-2.2 mm.This study provides a reference for the design of efficiently self-propelled nozzle for radial jet drilling technology. 展开更多
关键词 Radial jet drilling technology self-propelled nozzle Propulsive force Energy efficiency Cavitation model
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Evaluating the maneuverability of a new type of self-propelled barge
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作者 LUO Wei ZHANG Pan 《Journal of Marine Science and Application》 2007年第4期44-47,共4页
A new type of self-propelled barge was designed specifically for use on the Chishui River. This paper presents experimental results of its performance from tests in water of different depths,while bearing different lo... A new type of self-propelled barge was designed specifically for use on the Chishui River. This paper presents experimental results of its performance from tests in water of different depths,while bearing different loads. For test purposes,one of the best self-propelled barges from the Chishui River was used as a performance reference. The comparison showed that the new design has better maneuvering performance. 展开更多
关键词 self-propelled barge deep water shallow water maneuvering test
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Local Path Planning Method of the Self-propelled Model Based on Reinforcement Learning in Complex Conditions
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作者 Yi Yang Yongjie Pang +1 位作者 Hongwei Li Rubo Zhang 《Journal of Marine Science and Application》 2014年第3期333-339,共7页
Conducting hydrodynamic and physical motion simulation tests using a large-scale self-propelled model under actual wave conditions is an important means for researching environmental adaptability of ships. During the ... Conducting hydrodynamic and physical motion simulation tests using a large-scale self-propelled model under actual wave conditions is an important means for researching environmental adaptability of ships. During the navigation test of the self-propelled model, the complex environment including various port facilities, navigation facilities, and the ships nearby must be considered carefully, because in this dense environment the impact of sea waves and winds on the model is particularly significant. In order to improve the security of the self-propelled model, this paper introduces the Q learning based on reinforcement learning combined with chaotic ideas for the model's collision avoidance, in order to improve the reliability of the local path planning. Simulation and sea test results show that this algorithm is a better solution for collision avoidance of the self navigation model under the interference of sea winds and waves with good adaptability. 展开更多
关键词 self-propelled model local path planning Q learning obstacle avoidance reinforcement learning
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Ratchet transport of self-propelled chimeras in an asymmetric periodic structure
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作者 Wei-Jing Zhu Bao-Quan Ai 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期201-207,共7页
We studied the rectified transport of underdamped particles subject to phase lag in an asymmetric periodic structure.When the inertia effect is considered,it is possible to observe reversals of the average velocity wi... We studied the rectified transport of underdamped particles subject to phase lag in an asymmetric periodic structure.When the inertia effect is considered,it is possible to observe reversals of the average velocity with small self-propelled force,whereas particles always move in the positive direction with large self-propelled force.The introduction of phase lag leads particles to follow circular orbits and suppress the polar motion.In addition,this can adjust the direction of particle motion.There exists an optimal value of polar interaction strength at which the rectification is maximal.These results open the way for many application processes,such as spatial sorting of particles mixture and separation based on their physical properties. 展开更多
关键词 Brownian motion self-propelled particles stochastic processes
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Nonvanishing optimal noise in cellular automaton model of self-propelled particles
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作者 Guang-Le Du Fang-Fu Ye 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期561-565,共5页
A minimal cellular automaton model is introduced to describe the collective motion of self-propelled particles on two-dimensional square lattice. The model features discretization of directional and positional spaces ... A minimal cellular automaton model is introduced to describe the collective motion of self-propelled particles on two-dimensional square lattice. The model features discretization of directional and positional spaces and single-particle occupation on one lattice site. Contrary to the Vicsek model and its variants, our model exhibits the nonvanishing optimal noise. When the particle density increases, the collective motion is promoted with optimal noise strength and reduced with noise strength out of optimal region. In addition, when the square lattice undergoes edge percolation process, no abrupt change of alignment behaviors is observed at the critical point of percolation. 展开更多
关键词 self-propelled particle optimal noise cellular automaton
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Going in Homer:The Role of Verb-Inherent Actionality Within Self-Propelled Motion-Event Encoding
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作者 Castrenze Nigrelli 《Journal of Literature and Art Studies》 2019年第12期1275-1291,共17页
The paper aims at investigating the encoding of self-propelled motion events in Homeric Greek in the light of the typology of motion events,taking into account the case of to go.The verbal class of the self-propelled ... The paper aims at investigating the encoding of self-propelled motion events in Homeric Greek in the light of the typology of motion events,taking into account the case of to go.The verbal class of the self-propelled motion refers to those verbs expressing the idea of a simple translational motion,such as to go,to move,without any information about the manner of motion(see,by contrast,the class of the manner-of-motion verbs,such as to run,to swim)or about the path of motion(see,by contrast,the class of the path verbs,such as to enter,to exit).According to Talmy(2000),world languages can be distinguished depending on whether they prototypically express the semantic component of Path in or outside the motion verb.Languages belonging to the S(atellite)-Framed type tend to convey Path outside the motion verb,in a satellite element,such as a particle,an adposition(adpositional phrase),a preverb,an adverb(ial),a nominal case marker.The prototypical encoding pattern of the S-Framed languages,such as Homeric Greek,involves a motion verb conveying Manner and a satellite conveying Path,i.e.,[manner-of-motion verb+Path-satellite].Nonetheless,another pattern is used by this type of languages,albeit less prototypical,which involves a motion verb conveying only Motion and a satellite conveying Path,i.e.,[self-propelled motion verb+Path-satellite].Verb-inherent actionality,namely telicity,turns out to be a strong feature within the ancient Indo-European languages,such as Homeric Greek,playing a role not only in the development of aspectual/tense morphology,but also in the encoding of motion events,at least with reference to manner-of-motion verbs.The present paper aims at verifying the role of inherent telicity within self-propelled motion verbs,through the analysis of Homeric verbs for go.The study takes into account the Homeric suppletive paradigm for go,focusing on ερχομαι“go;come”and ηλθον(aorist)“go;come”(also with reference to the unclear actional opposition between ερχομαι and ειμι“go;come”).From the textual analysis of all the occurrences of both ερχομαι and ηλθον,as well as their co-occurring Path-encoding elements in the Iliad and the Odyssey,data show to what extent verbal inherent telicity plays an important role in motion event encoding also within the class of self-propelled motion verbs. 展开更多
关键词 actionality MOTION EVENT Homeric Greek GRAMMATICALIZATION self-propelLED MOTION VERBS
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Deployment of Self-Propelled Modular Transporter for Vessel Installation
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作者 Michael A. Stogdill Mohammad K. Al-Dossary Nezar H. Al-Khalifah 《Open Journal of Civil Engineering》 CAS 2022年第4期554-558,共5页
The traditional way of installing large vessels has always been to employ the use of cranes. The Water Handling Debottlenecking Project team has, instead, made use of a different technology—employing a Self-Propelled... The traditional way of installing large vessels has always been to employ the use of cranes. The Water Handling Debottlenecking Project team has, instead, made use of a different technology—employing a Self-Propelled Modular Transporter (SPMT) to install nine vessels in situ. These SPMT units have many advantages over crane installations, such as safety and efficiency, not to mention lower costs due to their self-propelled capabilities. 展开更多
关键词 self-propelled Modular Transporter (SPMT) TRANSPORTATION Vessel Transportation Vessel Installation Horizontal Vessel
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Development and Evaluation of Self-propelled Cabbage/Cauliflower Harvester
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作者 Jagvir Dixit Naieam Jan Rawat 《NASS Journal of Agricultural Sciences》 2022年第1期56-63,共8页
In the present study,self-propelled cabbage/cauliflower harvester was designed,developed and evaluated.The machine consisted of different components like engine,frame,shearing(cutting)unit and power transmission unit.... In the present study,self-propelled cabbage/cauliflower harvester was designed,developed and evaluated.The machine consisted of different components like engine,frame,shearing(cutting)unit and power transmission unit.The power transmission unit consisted of main clutch,shearing blade operating clutch,belt drive unit,chain and sprocket drive,universal joint and cutter blade assembly.The main working principle of harvester is based on shearing of crop stem against high-speed rotating blade.The power from the engine is transmitted by belt-pulley drive unit to transmission shaft on which chain and sprocket is mounted on one side and then power is transmitted to shearing blade coupling with the help of a stationary pulley and fixed socket.Average mean head diameter of the selected cabbage and cauliflower was 89.5±15.24 mm and 107.5±15.24 mm,respectively.Average mean stem(plant)diameter of the selected cabbage and cauliflower was 18±4.85 mm and 21.5±3.08 mm,respectively.The shearing force increased with increase in diameter of stem.The optimum performance of the machine was achieved when it was operated at 1.5 km/h forward speed and the shearing blade moving at speed of 147 rpm.The mean field capacity for developed prototype was observed as 0.063 ha/h and 0.053 in case of cabbage and cauliflower,respectively with field efficiency of 91.97 and 90.48%.The average head damage was negligible(0.15%)for both the crops.The average untrimmed percentage with developed harvester was 3.2 and 3.0%in case of cabbage and cauliflower crop,respectively.The developed machine helps to increase the field capacity in cabbage/cauliflower harvesting due to 7-times more capacity and 50%cheaper compared to traditional method of cabbage/cauliflower harvesting.At the operating condition of forward speed(1.5 km/h)and shearing blade speed(147 rpm),the machine could harvest 0.5 ha of cabbage and 0.42 ha of cauliflower farm per day of 8-h.This same task would have required between 15 labour per day if entirely done manually. 展开更多
关键词 self-propelLED HARVESTER Cabbage/cauliflower Field capacity Field efficiency Untrimmed percentage
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