scholarly journals WORKSPACE ANALYSIS OF A FLAME INTRA-ROW WEEDING ROBOT IN VEGETABLE FIELD AND NUMERICAL SIMULATION OF PROPANE COMBUSTION

2021 ◽  
pp. 73-81
Author(s):  
Bing Xu ◽  
Decong Zheng ◽  
Jiaxin Wang ◽  
Youzhi Yang
Keyword(s):  
High Speed ◽  
Simulation Method ◽  
Propane Combustion ◽  
Seed Filling ◽  
Element Simulation ◽  
Workspace Analysis ◽  
Optimal Value ◽  
Physical Prototype ◽  
Seed Metering Device

In order to improve the seed filling performance of mechanical hole type seed metering device with high speed, a vertical disc metering device was designed with seed agitator to improve the seed filling probability. Discrete element simulation method and physical prototype bench tests were used to simulate and analyse the seed metering process. The structure parameters of the seed agitators were optimized by the quadratic orthogonal rotation central composite design test. The results showed that: 1) the addition of seed agitator had a significant influence on the MIS (miss index), among which the concave type had the lowest MIS, and it was the highest without agitator; 2) for concave type agitator, the optimal value of depth and angle were 3.1 mm and 60.5°, respectively; 3) the physical prototype tests showed that the QFI (quality of feed index) was more than 95% under the speed of 2-10 km/h, and the MIS was less than 1%, which meets the requirements of precision sowing.

scholarly journals DESIGN AND EXPERIMENT OF SEED AGITATOR FOR VERTICAL DISK SEED METERING DEVICE

2021 ◽  
pp. 179-188
Author(s):  
Yulong Chen ◽  
Meng Zhang ◽  
Zeqi Liu ◽  
Yubin Lan ◽  
Lili Yi ◽  
...  
Keyword(s):  
High Speed ◽  
Simulation Method ◽  
Discrete Element Simulation ◽  
Seed Filling ◽  
Element Simulation ◽  
Optimal Value ◽  
Physical Prototype ◽  
Seed Metering Device ◽  
Central Composite

In order to improve the seed filling performance of mechanical hole type seed metering device with high speed, a vertical disc metering device was designed with seed agitator to improve the seed filling probability. Discrete element simulation method and physical prototype bench tests were used to simulate and analyse the seed metering process. The structure parameters of the seed agitators were optimized by the quadratic orthogonal rotation central composite design test. The results showed that: 1) the addition of seed agitator had a significant influence on the MIS (miss index), among which the concave type had the lowest MIS, and it was the highest without agitator; 2) for concave type agitator, the optimal value of depth and angle were 3.1 mm and 60.5°, respectively; 3) the physical prototype tests showed that the QFI (quality of feed index) was more than 95% under the speed of 2-10 km/h, and the MIS was less than 1%, which meets the requirements of precision sowing.

scholarly journals EFFECT OF SEED FILLING AND RELEASING ANGLES ON THE PERFORMANCE OF COMPOUND VACUUM SEED METERING DEVICE

2021 ◽  
pp. 153-162
Author(s):  
Zeqi Liu ◽  
Zhang Meng ◽  
Jie Han ◽  
Yajun Zhuang ◽  
Xiang Yin ◽  
...  
Keyword(s):  
Negative Pressure ◽  
High Speed ◽  
Test Results ◽  
Camera System ◽  
Seed Filling ◽  
Evaluation Indexes ◽  
Air Chamber ◽  
The Subject ◽  
Seed Metering Device

In this paper, taking compound air-suction seed metering device as the subject, the effect rule of seed filling angle and seed releasing angle on the performance of seed filling and seed metering is studied. An indoor test was conducted with a JPS-12 metering test bench and a high-speed camera system. The starting and ending angles of the air chamber were changed by adjusting the regulating plate, that is, the angles of seed filling and seed releasing, and the filling and seed metering performance was taken as evaluation indexes. The test results show that: the seed filling angle has significant effect on the seed filling effect, and the miss fill index decreases with the increase of the quality of fill index. When the seed filling angle exceeds 50°, they will stabilize gradually ending at the multiple fill index of 0%. The negative pressure and operating speed are interactive and have a significant effect on filling performance. The seed releasing angle has significant effect on the metering performance. With the increase of the angle, the quality of feed index increases firstly and then decreases. The multiple index and miss index are opposite to the quality of feed index which is the max at the seed releasing angle of 39.5°. The negative pressure and forward speed are interactive and have a significant effect on metering performance. The quality of feed index under the same condition is lower than that of fill index.

Multiple Influencing Factors Analysis for Non-Conformal Contact Characteristics of Ball Screw

2011 ◽  
Vol 199-200 ◽  
pp. 707-714
Author(s):  
Fu Ji Wang ◽  
Jian Wei Ma ◽  
Zhen Yuan Jia ◽  
Jiang Yuan Yang ◽  
Di Song
Keyword(s):  
High Speed ◽  
Contact Stiffness ◽  
Simulation Method ◽  
Transmission Efficiency ◽  
Ball Screw ◽  
Design Parameters ◽  
Heavy Load ◽  
Theoretical Support ◽  
Element Simulation ◽  
Conformal Contact

The contact between balls and screw races or nut races is a kind of typical non-conformal contact. The study of contact characteristics of ball screw will provide theoretical bases for improving transmission efficiency and working properties of ball screw. In this study, hertz contact theory was adopted to construct the solution formula of ball screw’s contact stiffness, ball screw’s contact characteristics in terms of axial load, design parameters and material properties was analyzed, and the contact deformation value of the contact between ball and screw races was got using finite element simulation method. The simulation result is close to the theoretic value, which proves the correctness of the theory analysis. The present study offers theoretical support for the design and application of high speed, heavy load and precision ball screws.

Vibration Control of HSM of Thin-Wall Titanium Alloy Components Based on Finite Element Simulation

2016 ◽  
Vol 836-837 ◽  
pp. 304-309 ◽  
Author(s):  
Kang Zhao ◽  
Hong Hua Su ◽  
Lin Jiang He ◽  
Ying Zhi Liu
Keyword(s):  
Finite Element ◽  
Titanium Alloy ◽  
High Speed ◽  
Element Model ◽  
Fixture Design ◽  
Thin Wall ◽  
Element Simulation ◽  
Flexible Workpiece ◽  
Fixture System

During high-speed machining, the vibration will result in poor workpiece surface and damage the cutting tool as well as the machine tool. It will limit the productivity and lower the quality of thin-wall titanium alloy components. Moreover, vibration occurrence is strongly affected by the dynamic response of the whole system, particularly the stiffness of workpiece-fixture system. Improper fixture layout is prone to generate vibration, especially for the flexible workpiece. Hence, it’s necessary to suppress the vibration and improve the fixture design. In this work, a finite element model of the workpiece-fixture system is built. Based on this model, the laws of the natural frequency and vibration modals under different fixturing methods are obtained, which can be used to refine fixture design. With several additional auxiliary supports, the stiffness of the workpiece-fixture system is improved and the result showed that, the natural frequencies of thin-wall titanium alloy components can be improved to a level which is too high to be reached by tool’s excitation. The result of this study is helpful to design the optimum fixture scheme of thin-wall titanium alloy components.

The Influence Factor Analysis for Coupling Performance of HSK Tool System

2011 ◽  
Vol 480-481 ◽  
pp. 1225-1229 ◽  
Author(s):  
Chun Jiang Zhou
Keyword(s):  
High Speed ◽  
Influence Factor ◽  
Torsional Stiffness ◽  
Radial Deformation ◽  
High Speed Machining ◽  
Coupling System ◽  
Element Simulation ◽  
Coupling Performance ◽  
Tool Shank

The coupling performance of tool system is the important factor for the machining quality of high speed machining. Based on the deformation of contact surfaces of HSK tool system, the paper makes the academic analysis by elasticity theory and finite element simulation to high speed spindle/tool shank coupling system. The property of the contact stress and the radial deformation as well as the torsional stiffness with different amount of interference has been analyzed. In this method, the paper brings forward how the amount of interference will affect the coupling performance. Thus, it will give academic evidence to design and select tool system in the process of high speed machining.

The Experimental Modal Analysis of High Speed Machining Tool System Based on Integral Polynomial Recognition Method

2012 ◽  
Vol 723 ◽  
pp. 159-163 ◽  
Author(s):  
Fei Xiao ◽  
Xian Li Liu ◽  
Yan Xin Wang ◽  
Li Jia Liu ◽  
Da Qu
Keyword(s):  
Modal Analysis ◽  
High Speed ◽  
Simulation Method ◽  
Experimental Modal Analysis ◽  
Modal Parameters ◽  
High Speed Machining ◽  
Analysis Method ◽  
Recognition Method ◽  
Element Simulation ◽  
Integral Polynomial

According to the principle of the experimental modal analysis, this study is based on tool system of the MIKRON UCP 710 numerical control machining center as test object for experimental modal analysis. Using the integral polynomial recognition method to identify the modal parameters (natural frequency, structural damping, and modal shape), and finally matching the results with the vector analysis method and the finite element simulation method. The results show that integral polynomial recognition method has higher precision than the vector analysis method to identify the multi-degree of freedom system; the experimental modal analysis can also obtain better modal parameters of the structure system, and a higher precision than the finite element simulation method. Obtained the MIKRON UCP 710 high-speed milling center tool system accurate modal parameters provides the necessary theoretical and experimental basis for the further study of the stability properties in the cutting processing of the high speed machining tool system.

Forging Process Design and Simulation Optimization of a Complex-Shaped Aluminium Alloy Component

2018 ◽  
Vol 941 ◽  
pp. 784-789 ◽  
Author(s):  
Yan Chen ◽  
Song Wei Wang ◽  
Hong Wu Song ◽  
Shi Hong Zhang
Keyword(s):  
High Speed ◽  
Metal Flow ◽  
Simulation Method ◽  
Production Test ◽  
Alloy Component ◽  
High Speed Rail ◽  
Forging Process ◽  
Good Surface ◽  
Element Simulation ◽  
Steel Castings

In order to meet the requirements of lightweight and replace steel with the aluminum for a component on the high speed rail, the forging process of a complex-shaped aluminum alloy component was researched and the parameters were optimized with the DEFORM-3D finite element simulation technology. The qualified products were finally obtained instead of the original steel castings by reducing weight of 65%. It is noted that the parts with complicated shape and non-symmetry, metal flow uneven during forging process that lead to incomplete forming, higher forging pressure problems. In this paper, such problems were analyzed couple with numerical simulation method based on a certain forming pressure. Moreover, the model and slot was reasonably designed. In addition, the size of blank was constantly optimized to change the metal flows direction and cavity filling mode. Finally, the forgings with good surface quality and mechanical properties were obtained by production test, and can be used as reference for this kind of forging components.

scholarly journals Simulation of Sesame Seeds Outflow in Oscillating Seed Metering Device Using DEM

2020 ◽  
Vol 30 (2) ◽  
pp. 219-231
Author(s):  
Noureldin N. Sharaby ◽  
Artyom A. Doroshenko ◽  
Andrey V. Butovchenko
Keyword(s):  
Coming Out ◽  
High Speed ◽  
Sliding Friction ◽  
Sesame Seed ◽  
Simulation Method ◽  
Geometric Parameters ◽  
Sesame Seeds ◽  
Outflow Rate ◽  
Precision Planting ◽  
Seed Metering Device

Introduction. Sesame crop is one of the most important export crops in many countries around the world, especially in Africa. To meet the agricultural requirement of precision planting, various types of precision seed planters have been developed. Numerous studies were carried out to study the optimisation of the parameters of the precision planting. One of these parameters, affecting the quality of the precision seeder, is the grain outflow from the seed metering device. Materials and Methods. In order to maintain good continuous performance of an oscillating seeder, it is important to monitor seed flow in real-time and adjust oscillation parameters automatically. Existing research methods, such as prototyping and monitoring the process using a high-speed camera, by reason of the random movement of particles, do not allow obtaining sufficient data to understand trajectories and velocities of particles and existing equations for particle motion when simulating the sowing process do not allow taking into account the interaction of particles that having various shapes, rolling and sliding friction coefficients, and the elastic modulus of particle materials and a working body. In this study, the outflow rate of sesame seeds in an oscillating seed metering device was modeled using the simulation method based on the discrete element method. The aim of this study is to create a simulation model of an oscillating-type sowing planter using the sowing sesame seeds as an example for evaluating the effectiveness of this model, and the possibility of further optimization and prediction of sowing seeds with this device. Results. The analysis of the results showed that during the simulation, the sowing rate of sesame seeds when leaving the oscillating seed metering holes has significant differences in number and direction. The results of the modeling process in this study showed that when opening a hole in the oscillating seeder, a number of sesame seeds from 0 to 4 were coming out of it. The resulting model allows monitoring the behavior of each particle of a sesame seed, analyzing its trajectory, speed, and forces acting on it at any one time, and varying the parameters to obtain the dependence of uneven seeding on the kinematic and geometric parameters of the device. Discussion and Conclusion. The obtained simulation results provide an effective method for predicting the consumption of sesame seeds from the oscillating seed meter, which serves as the basis for optimizing the kinematic and geometric parameters of the oscillating sowing device in order to increase its efficiency. This model is universal and can be adapted to sow other crops.

Design an Effective Solution for Stretch Forming of Sheet Metal with a Shorter Free Edge

2013 ◽  
Vol 395-396 ◽  
pp. 941-944
Author(s):  
Qi Gang Han ◽  
Qiang Zhang ◽  
Ming Zhe Li ◽  
Shi Zhong Su ◽  
Wen Ke Yang ◽  
...  
Keyword(s):  
Finite Element ◽  
High Speed ◽  
Free Edge ◽  
Effective Solution ◽  
High Speed Train ◽  
Stretch Forming ◽  
High Quality ◽  
Forming Technology ◽  
Element Simulation

To remove the disadvantage of conventional stretch forming machine (CSFM), a flexible stretch forming machine (FSFM) has been developed by authors recently. Based on finite element simulation and experiments, the advantages of FSFM have been detailed discussed. Our results indicated that the discrete multi-gripping jaws can swing and rotate in any direction automatically, which can solve the wasteful production of CSFM by increase the rate of materials utilization and close-fitting dies. Furthermore, the value of springback and thickness gradient in the parts formed by discrete multi-gripping jaws is smaller compare with that of integrally gripping jaws, which can help to achieve a high quality of stretch forming parts. A series of double-curved sheet panels have been formed by FSFM easily and used in the cabinet covers of high-speed train and the Dongdaemun Design Park building successfully. This work has a strong value in enhance the way to flexible and reproducible stretch forming technology.

Sign in / Sign up

Export Citation Format

Share Document