scholarly journals Optimal Design and Simulation Analysis of Spike Tooth Threshing Component Based on DEM

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1163
Author(s):  
Yajun Yu ◽  
Liangshan Li ◽  
Jiale Zhao ◽  
Xiangeng Wang ◽  
Jun Fu

This paper takes a local drum-type corn thresher as an example. In order to make the threshing principle transform to the plate-tooth type, the width of the spike-tooth threshing component is increased gradually, and three threshing components of different shape and size are selected as the research objects. Based on the preliminary experimental research, the corn threshing process is simulation analyzed using the self-developed corn threshing process analysis software. The effects of the width of the threshing component on the corn ears threshing rate and kernel damage rate under different rates of drum rotation were studied from a macroscopic perspective. The results show that with the increase of drum rotation rate, both the corn ear threshing rate and kernel damage rate increase; with the increase of threshing component width, the threshing rate increases and the damage rate decreases; and when the component width is too large, the stacking between adjacent components has an impact on the threshing performance. The effects of threshing component width on the amount of kernel threshing and the total compressive force during the simulation time were investigated from microscopic perspective at different rates of drum rotation, and the results show that the microscopic analysis is consistent with the macroscopic analysis. Therefore, the optimization of the structural parameters and operating parameters of the threshing component was achieved. When the width of the threshing component was 25 mm and the roller speed was 187.50 rpm, the threshing performance was optimal, with a 98.04% corn ears threshing rate and a 2.56% kernel damage rate. This paper verifies the practical applicability of the corn threshing process analysis software and provides a reference for the optimal design of threshing devices.

2012 ◽  
Vol 499 ◽  
pp. 120-125 ◽  
Author(s):  
Zhi Peng Tang ◽  
Ying Xue Yao ◽  
Liang Zhou ◽  
Q. Yao

In order to enhance the efficiency of the Savonius rotor, this paper designs a new type of Savonius rotor with a rectifier. By using Computational Fluid Dynamics software to simulate and optimize the various parameters which affect the efficiency of the rotor. The sliding mesh method is applied here. The Cp-λ curves of wind turbine with different structural parameters are obtained after numerical simulation of flow field. On this basis, this paper gets the optimal structural parameters. And the results indicated that this new type of Savonius rotor has great improvement of efficiency compared with the traditional Savonius-type rotor.


Author(s):  
Zhang Bao ◽  
Wang Xiaoping ◽  
Ge Xinfang

To reduce negative stiffness structure’s stiffness non-linearity, enhance its stability during entire working displacement range, and expand its allowable working displacement, the optimal design of negative stiffness structure based on magnetic repulsion is proposed, and its structural parameters are also provided. The new negative stiffness structure’s model is established to determine the structural design parameters. According to the change of the new negative stiffness structure’s stiffness curve, we select the structural parameter to meet the design requirements. In order to verify the effectiveness of the proposed negative stiffness structure, we carried out simulation analysis, and the results show that the optimized negative stiffness structure’s stiffness non-linearity is greatly reduced in a relatively longer displacement, and its stiffness stability is promoted substantially compared with the simple triple-magnet negative stiffness structure.


2021 ◽  
pp. 146808742199698
Author(s):  
Lyu Xiuyi ◽  
Abdullah Azam ◽  
Wang Yuechang ◽  
Lu Xiqun ◽  
Li Tongyang ◽  
...  

The piston ring-cylinder liner (PRCL) is one of the most important parts of marine diesel engines and contributes 25% to 50% of total friction loss. The lubrication simulation analysis of the PRCL system is a challenging task. Complete understanding and precise prediction of lubrication loads is a key to understanding the friction behavior of PRCL systems as the accuracy of the friction prediction depends upon precise prediction of lubrication loads. Therefore, this paper focuses on the gas pressure calculation which is the primary source of lubrication loads. The procedure presented combines the advantages of two mainstream methods to predict loads in the PRCL system. The result is a significant reduction in the computation time without compromising on accuracy. Firstly, a comparison of both approaches is presented which suggests that each technique has its limitations (one is time-bound, and one is accuracy-bound). Then, the results from both calculation methods are verified against literature and a parametric study is performed to identify the key structural parameters of PRCL system that affect the calculation efficiency. Finally, a correlation coefficient is introduced into the analysis to combine the two approaches which then identifies the conditions under which the use of the faster method becomes invalid and replaces it with the more accurate approach. This ensures optimum performance of the calculation procedure by switching between the fast and the accurate method depending upon the accuracy requirement under given conditions, thereby, simplifying the dynamic and lubrication model of PRCL systems. The study has direct implications for the tribological design of the PRCL interface.


2012 ◽  
Vol 487 ◽  
pp. 203-207
Author(s):  
Gong Xue Zhang ◽  
Xiao Kai Shen

Purpose, with the application of workbench finite element analysis software, get the analysis results of DVG 850 high-speed vertical machining center via the modal analysis and harmonic response analysis. Use the calculation results for reference, put forward the improved method, and prove the credibility of the simulation analysis by testing DVG 850 prototype.


2014 ◽  
Vol 488-489 ◽  
pp. 589-592
Author(s):  
Min Tan

Inverted siphon structure is a common water conveyance buildings, computer as a efficient computational tool is used, this paper adopt finite element method to carry out three-dimensional finite element simulation analysis for Dahedong inverted siphon structure. Deducing variation law of the inverted siphons stress and displacement in construction process and operating process. Analysis results further verified that design scheme is reasonable and safe, it has certain application value.


2015 ◽  
Vol 645-646 ◽  
pp. 841-846 ◽  
Author(s):  
Jian Yan Wang ◽  
Ting Ting Wang ◽  
Hang Guo

Accelerometer in MEMS always is made by capacitive or piezoresistive, whose dynamic response is not good, the operating frequency is narrow, and the cross-axis sensitivity is low. A new type of piezoelectric micro-accelerometer is designed, and its structure is “x” type. The sensing unit is piezoelectric PZT films, which is achieved by sol-gel method. The accelerometer is a triaxial accelerometer. The theoretical and simulation analysis is used to achieve the charge sensitivity and response frequency, and also get the optimal structural parameters. A new circuit connection is proposed to improve the sensitivity and avoid the cross-axis sensitivity. The design achieves the z-axis sensitivity with more than 40 pC/g, x, y-axis sensitivity with more than 8pC/g, and the response frequency is about 3000Hz.


2014 ◽  
Vol 529 ◽  
pp. 410-414
Author(s):  
Cang Zhao ◽  
Guang Li Song ◽  
Lei Xu

By combining the industrial design software UG and finite element dynamic analysis software ANSYS/LS-DYNA, the paper respectively designs the non-linear knitting cams with polynomial curves, and simulates the loop-forming process in the interaction between the cams and needles. Based on comparative analyses, it’s thereby concluded that the polynomial curve has the best performance and is significantly superior to the cam curve composed of straight-lines and circular-arcs; the elements with higher stresses are located above the butt of needle jack and the joint of the jack and latch needle; and the polynomial curve is effective in lowering the maximum stress of the needle.


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