scholarly journals Design and Experimental Study of a Wine Grape Covering Soil-Cleaning Machine with Wind Blowing

2021 ◽  
Vol 3 (1) ◽  
pp. 50-72
Author(s):  
Qizhi Yang ◽  
Mingsheng He ◽  
Guangyu Du ◽  
Lei Shi ◽  
Xiaoqi Zhao ◽  
...  
Keyword(s):  
Removal Rate ◽  
Winter Season ◽  
Central Area ◽  
Thick Layer ◽  
Simulation Software ◽  
Fluid Simulation ◽  
Two Phase ◽  
Wind Speeds ◽  
Damage Rate ◽  
Cleaning Machine

Due to the cold and dry climate during the winter season of Central Asia, in order to prevent frostbite and vines drying out for wine grapes, the common methods are burying the vines in winter under a thick layer of soil and then cleaning them out in the next spring. The design of existing vine digging machinery is not precise enough and can only remove the outer layer of the soil on both sides and the top. It cannot clean the soil from the central area of the buried vine. Sometimes, the branches and buds get damaged due to uneven driving condition. To solve the problem, an innovative non-contact blower was designed and tested to clean the vine. In this paper, the design specifications and operation parameters of the blower were determined according to the agronomic properties of the grapevines. Fluent-EDEM coupling, that is, with the help of Engineering discrete element method (EDEM) and CFD fluid simulation software Fluent, was the most common method for dynamic simulation of gas-solid two-phase flow. The Fluent-EDEM coupling simulation was used to simulate the dynamics of soil particles under the action of different wind speeds and blowing patterns, with the goal of a high soil cleaning rate. A prototype of the soil cleaning blower was manufactured and tested at the vineyards of Ningxia Yuquanying Farm in China. The results showed that the blower had an operation efficiency of 4669 m2·h−1, with an average soil removal rate of 80%. The efficiency of covering soil cleaning and rattan raising was greatly improved, and the damage rate of the vines, branches and the buds was greatly reduced.

Numerical Simulation on the Solidification of ZA27 Alloy by a Two-Phase Flow Model

2005 ◽  
Vol 475-479 ◽  
pp. 3203-3206
Author(s):  
Zhan Ling Zhang ◽  
Liu Shuan Yang ◽  
Feng Ni
Keyword(s):  
Flow Model ◽  
Two Phase Flow ◽  
Concentration Field ◽  
Solidification Process ◽  
Simulation Software ◽  
Fluid Simulation ◽  
Phase Flow ◽  
Two Phase ◽  
Za27 Alloy ◽  
Cylindrical Coordinate

ZA27 alloy solidifies in the way of paste-solidification, and results in gravity segregation. The two-phase flow model was developed on the basis of the solidification characteristic of the ZA 27 alloy. And the governing equations of the solidification process were differentiated and computed in a 3-D cylindrical coordinate system through a heat and fluid simulation software package (PHOENICS). The computation of the concentration field indicated a segregation of Al, and is in good agreement with the experiments. This model could simulate the convection and the gravitational segregation during the solidification.

Design and simulation research of the double-spin folding mechanism based on a suspended missile

2021 ◽  
pp. 154851292110231
Author(s):  
ZH Yuan ◽  
SY Guo ◽  
SN Zhang ◽  
JQ Zhao ◽  
WJ Lu ◽  
...  
Keyword(s):  
High Reliability ◽  
Lift Coefficient ◽  
Great Influence ◽  
Reference Value ◽  
Aerodynamic Characteristics ◽  
Simulation Software ◽  
Fluid Simulation ◽  
Simulation Research ◽  
Double Spin ◽  
Locking Mechanism

Based on the suspension of a missile using folding rotary wings and airbags, in order to improve the basic parameters and motion characteristics of the rotor during the unfolding process and analyze the aerodynamic characteristics of the entire device in the suspension state, after proposing a scheme of double-spin mechanism, the main folding and unfolding mechanism, initial driving device, rotating driving device, and locking mechanism were designed, and the simulation research is studied by the Automatic Dynamic Analysis of Mechanical System and Ansys Fluent Fluid Simulation software, respectively. The results show that the rotation rate was controlled at 41.8 mm/s, the various motion parameters are reasonable, and the operation process is relatively smooth, with high reliability. The speed and pressure value at the tip of the rotor are higher and the aerodynamic disturbance is obvious, which has a great influence on the aerodynamic performance. The speed and pressure distribution of the surrounding flow field is stable, the lift provided is 46 N, and the lift coefficient is 0.55, which can ensure the long-time suspension state of the missile. This paper puts forward a valuable design idea and has practical reference value for the research of the suspended missile.

The Research of Marine Nuclear Power Two Loop Simulation Software Based on the Thermal System Analysis

2014 ◽  
Vol 983 ◽  
pp. 288-291
Author(s):  
Guo Lei Zhang ◽  
Xiang Dong Jin ◽  
Zhan Zhao ◽  
Zhi Jun Shi
Keyword(s):  
Nuclear Power ◽  
System Analysis ◽  
Simulation Analysis ◽  
Simulation Software ◽  
Operating Conditions ◽  
Two Phase ◽  
Design Data ◽  
Software Optimization ◽  
Power Simulation ◽  
Basic Functions

To study of Nuclear power simulation software's basic functions and mathematical model based on thermal analysis. Describes the two-phase flow model of GSE software superiority, as well as the software optimization program .Use of software tools for normal operating conditions of the simulation calculation and analysis of the results. Comparison with design data shows that,the software use in marine nuclear power two loop system simulation analysis field, the accuracy of it is higher.

scholarly journals Research on the Influence of the Distribution Pattern of Building Clusters in Coastal Areas on Wind Environment -Focused on Busan area in Korea

2021 ◽  
Vol 308 ◽  
pp. 02010
Author(s):  
Yang Huimin ◽  
Zhao Shuwen ◽  
Kim Chulsoo
Keyword(s):  
Thermal Environment ◽  
Simulation Software ◽  
Fluid Simulation ◽  
Wind Environment ◽  
Environment Quality ◽  
Ventilation Efficiency ◽  
Urban Thermal Environment ◽  
The City ◽  
Public Environment

With the development of urbanization, the heat island phenomenon has led to further deterioration of the urban thermal environment, resulting in wind environment differences. To study the thermal environment of the city, this paper takes the Busan area in South Korea as the research object and analyzes the connection between the layout of buildings and the wind environment based on the microscopic wind environment characteristics of the coastal area using CFD air-fluid simulation software and suggests that the monsoon influence brought by the coastal currents should be paid attention to, the layout of wind-oriented building groups should be improved, urban air ducts should be established to enhance the ventilation efficiency, and the wind environment of the urban public environment and buildings should be guaranteed. The wind environment quality of urban public environment and indoor environment should be ensured.

scholarly journals Simulation Analysis of Erosion–Corrosion Behaviors of Elbow under Gas-Solid Two-Phase Flow Conditions

Lubricants ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 92
Author(s):  
Qunfeng Zeng ◽  
Wenchuang Qi
Keyword(s):  
Chemical Reaction ◽  
Simulation Analysis ◽  
Electrochemical Corrosion ◽  
Simulation Software ◽  
Solid Particles ◽  
Two Phase ◽  
Particle Count ◽  
Coal Gas ◽  
Erosion Corrosion ◽  
Corrosion Behaviors

In the production and gathering process of coal gas, the complex composition of the coal gas, harsh environments, the complex medium, and high content of solid particles in slurry cause the equipment malfunctions and even failure because of erosion and corrosion. In the present study, COMSOL multi-physics finite element simulation software is used to simulate the erosion–corrosion behaviors of elbow in key chemical equipments. The electrochemical corrosion, solid particle erosion, chemical reaction, and turbulent flow are coupled together. The particle count method is proposed to clarify the erosion phenomenon. The simulation results show that particles with high turbulent intensity hit the wall of elbow directly, which forms a slanted elliptical erosion zone on the extrados surface at 40°–50°. The chemical reaction in turbulence has a difference in the concentration distribution of substances, and this phenomenon leads to different magnitudes of the corrosion current densities in the tube. Moreover, 1/6 released particles hit the extrados surface of the elbow. These findings are beneficial to understand the erosion–corrosion phenomena and design the elbow in key chemical equipment.

scholarly journals Analysis of temperature characteristics of ink fluid based on power law model in microchannel

2019 ◽  
Vol 11 (3) ◽  
pp. 168781401983358
Author(s):  
Hongyan Chu ◽  
Xuecong Lin ◽  
Ligang Cai
Keyword(s):  
Heat Transfer ◽  
Viscous Dissipation ◽  
Power Law ◽  
Flow Characteristics ◽  
Simulation Software ◽  
Fluid Simulation ◽  
Fluid Temperature ◽  
Power Law Model ◽  
Feature Size ◽  
Temperature Characteristics

In the offset press, ink flows in the microchannel made of two rotating rollers that are in the state of squeezing and contacting. The ink flow characteristics are not only influenced by the viscous dissipation effect, but also change with the heat transfer. First, by summarizing the common viscosity–shear rate models of non-Newtonian fluid, the power law model was chosen for describing offset ink through rheometer measuring. Combined with the experimental data, the viscosity–temperature relationship of the offset ink was described by the Arrhenius’s law. Then, the temperature characteristics of the offset ink fluid in the microchannel were studied using the fluid simulation software FLUENT. The ink fluid temperature field model considering viscous dissipation and heat transfer was established, and the temperature distributions of the ink fluid inside the microchannel and at the exit and entrance were obtained. The influence of the feature size on the ink temperature was also researched. Finally, the ink temperature and flow characteristics were compared with that under the condition without heat transfer. We got the influence of feature size and heat transfer on the ink temperature characteristics. As the feature size is smaller, the ink temperature increase from the microchannel entrance to the exit, increases first and then decreases, and keeps invariant at last. The heat transfer makes the viscous dissipation weaken relatively and then the ink temperature decreases. In a word, the heat transfer enhances as the feature size decreases. The results provide reference for improving the printing quality of offset press.

scholarly journals Anatomy of the massive star-forming region S106

2018 ◽  
Vol 617 ◽  
pp. A45 ◽  
Author(s):  
N. Schneider ◽  
M. Röllig ◽  
R. Simon ◽  
H. Wiesemeyer ◽  
A. Gusdorf ◽  
...  
Keyword(s):  
Binary System ◽  
High Velocity ◽  
Central Area ◽  
Line Emission ◽  
Two Phase ◽  
Star Forming ◽  
Projected Length ◽  
Molecular Lines ◽  
Dark Lane ◽  
Gas Accretion

The central area (40″  × 40″) of the bipolar nebula S106 was mapped in the [O I] line at 63.2 μm (4.74 THz) with high angular (6″) and spectral (0.24 MHz) resolution, using the GREAT heterodyne receiver on board SOFIA. The spatial and spectral emission distribution of [O I] is compared to emission in the CO 16 →15, [C II] 158 μm, and CO 11 →10 lines, mm-molecular lines, and continuum. The [O I] emission is composed of several velocity components in the range from –30 to 25 km s−1. The high-velocity blue- and red-shifted emission (v = −30 to –9 km s−1 and 8 to 25 km s−1) can be explained as arising from accelerated photodissociated gas associated with a dark lane close to the massive binary system S106 IR, and from shocks caused by the stellar wind and/or a disk–envelope interaction. At velocities from –9 to –4 km s−1 and from 0.5 to 8 km s−1 line wings are observed in most of the lines that we attribute to cooling in photodissociation regions (PDRs) created by the ionizing radiation impinging on the cavity walls. The velocity range from –4 to 0.5 km s−1 is dominated by emission from the clumpy molecular cloud, and the [O I], [C II], and high-J CO lines are excited in PDRs on clump surfaces that are illuminated by the central stars. Modelling the line emission in the different velocity ranges with the KOSMA-τ code constrains a radiation field χ of a few times 104 and densities n of a few times 104 cm−3. Considering self-absorption of the [O I] line results in higher densities (up to 106 cm−3) only for the gas component seen at high blue- and red velocities. We thus confirm the scenario found in other studies that the emission of these lines can be explained by a two-phase PDR, but attribute the high-density gas to the high-velocity component only. The dark lane has a mass of ~275 M⊙ and shows a velocity difference of ~1.4 km s−1 along its projected length of ~1 pc, determined from H13CO+ 1 →0 mapping. Its nature depends on the geometry and can be interpreted as a massive accretion flow (infall rate of ~2.5 × 10−4 M⊙ yr−1), or the remains of it, linked to S106 IR/FIR. The most likely explanation is that the binary system is at a stage of its evolution where gas accretion is counteracted by the stellar winds and radiation, leading to the very complex observed spatial and kinematic emission distribution of the various tracers.

Image Reconstruction Algorithm Based On PCA and WNN for ECT

2013 ◽  
Vol 5 (4) ◽  
pp. 33-40
Author(s):  
Lifeng Zhang
Keyword(s):  
Image Reconstruction ◽  
Adaptive Learning ◽  
Transfer Functions ◽  
Measurement Data ◽  
Principal Component ◽  
Reconstruction Algorithm ◽  
Simulation Software ◽  
Iteration Algorithm ◽  
Two Phase ◽  
Image Reconstruction Algorithm

Electrical capacitance tomography (ECT) technique is a new technique for two-phase flow measurement. ECT is a complex nonlinear problem. To solve the ill-posed image reconstruction problem, image reconstruction algorithm based on wavelet neural networks (WNN) was presented. The principal component analysis (PCA) method was used to reduce the dimension of the input vectors. The transfer functions of the neurons in the WNN were wavelet base functions which were determined by retract and translation factors. The input measurement data were obtained using the ECT simulation software developed by the author. BP algorithm was used to train the WNN, and self-adaptive learning rate and momentum coefficient were also used to accelerate the learning speed. Experimental results showed the image quality has been improved markedly, compared with the typical linear back projection (LBP) algorithm and Landweber iteration algorithm.

scholarly journals Water-Exit Process Modeling and Added-Mass Calculation of the Submarine-Launched Missile

2017 ◽  
Vol 24 (s3) ◽  
pp. 152-164 ◽  
Author(s):  
Jian Yang ◽  
Jinfu Feng ◽  
Yongli Li ◽  
An Liu ◽  
Junhua Hu ◽  
...  
Keyword(s):  
Dynamic Model ◽  
Calculation Method ◽  
Added Mass ◽  
Simulation Software ◽  
Fluid Simulation ◽  
Modeling Process ◽  
Complex Fluid ◽  
Simulated Analysis ◽  
Changing Rate ◽  
Water Exit

Abstract In the process that the submarine-launched missile exits the water, there is the complex fluid solid coupling phenomenon. Therefore, it is difficult to establish the accurate water-exit dynamic model. In the paper, according to the characteristics of the water-exit motion, based on the traditional method of added mass, considering the added mass changing rate, the water-exit dynamic model is established. And with help of the CFX fluid simulation software, a new calculation method of the added mass that is suit for submarine-launched missile is proposed, which can effectively solve the problem of fluid solid coupling in modeling process. Then by the new calculation method, the change law of the added mass in water-exit process of the missile is obtained. In simulated analysis, for the water-exit process of the missile, by comparing the results of the numerical simulation and the calculation of theoretical model, the effectiveness of the new added mass calculation method and the accuracy of the water-exit dynamic model that considers the added mass changing rate are verified.

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