scholarly journals Interval Multi-Objectives Optimization of Electric Wheel Dump Truck Frame Based on Blind Number Theory

2019 ◽  
Vol 9 (20) ◽  
pp. 4214
Author(s):  
Chengji Mi ◽  
Jidong Liu ◽  
Xuewen Xiao ◽  
Jinhua Liu ◽  
Rui Ming ◽  
...  
Keyword(s):  
Number Theory ◽  
Optimization Design ◽  
Mechanical Performance ◽  
Sampling Technique ◽  
Torsional Stiffness ◽  
Open Pit ◽  
Dump Truck ◽  
Main Bearing ◽  
Blind Number ◽  
Strength And Stiffness

With respect to heavy carrying tasks and uneven road surface in open pit mine, the mechanical performances of electric wheel dump truck frame regarded as the main bearing component are extremely important for its safe operation. For the problem of insufficient strength and stiffness, an interval multi-objectives optimization design method based on blind number theory is presented in this paper, taking into account uncertain factors caused by manufacturing process. The allowable interval strength of welding material and permissible interval bending and torsional stiffness are obtained by means of experiments and simulations, using the blind number theory. Based on Latin hypercube sampling technique, the strength and stiffness of frame under different conditions is estimated. It shows that in the case of braking interference between interval strength and interval dynamic stress appears. Strength and stiffness are considered as optimization objectives, while the thicknesses of top longitudinal beam, stiffener, lateral longitudinal beam and hanging ear in the frame are deeded as design variables, and Young’s modulus and Poisson’s ratio are taken as uncertain variables. The optimized results show that the stress and deformation of the frame due to dynamic loading decreased. This result enables to formulate the following sentence: the mechanical performance of frame is improved.

Analysis of Finite Element and Optimization Design of Mechanical Excavator Rotary Platform

2013 ◽  
Vol 706-708 ◽  
pp. 1205-1208
Author(s):  
Jia Li ◽  
Xiang Wei Kong ◽  
Lin Li ◽  
Meng Zhao
Keyword(s):  
Finite Element ◽  
Optimization Design ◽  
Structural Characteristics ◽  
Element Model ◽  
Open Pit ◽  
Open Pit Mining ◽  
Main Bearing ◽  
Design Variables ◽  
Rotary Platform ◽  
Weight Decrease

The mechanical excavator is the essential equipment for open-pit mining. The rotary platform is main bearing part of the excavator, stiffness and strength are directly related to the safety of the excavator. The rotary platform of a mechanical excavator is applied as the research object. The Shell181 and Solid 95 unit are used to establish finite element model based on analyzing the structural characteristics. MPC technology is applied to solve the coupling problem of the shell and the solid element. Taking the total weight of platform as the objective function of optimization, stiffness and strength condition as constraint conditions, the section thickness of the platform main components as the design variables, the structural optimization of the platform has been completed, and the weight decrease by 6.55%. A new way has been explored to make the design of platform structure more economic and reasonable, and improve the design efficiency.

Reliability Optimization Design Based on the Blind Number Theory

2012 ◽  
Vol 217-219 ◽  
pp. 1385-1388
Author(s):  
De Xiang Zhao ◽  
Yong Cheng Ling ◽  
Ju Zhao
Keyword(s):  
Number Theory ◽  
Optimization Design ◽  
Design Method ◽  
Design Model ◽  
Reliability Optimization ◽  
Reliability Design ◽  
Operation Rules ◽  
Blind Number

The concept and operation rules of the blind number based on Unascertained Theory are introduced. This case study demonstrates the advantage of unascertained theory described in reliability optimization, and a stress-strength reliability optimization design model is built up at same time. In addition, the corresponding practical optimization calculating program is given. Test on the validity and practicability of this model is also verified by comparing the result of reliability gained from this model with that obtained from the traditional reliability-design method.

Lateral Load Performance of Panelized Wood I-Joist Floor Systems

2020 ◽  
Vol 70 (4) ◽  
pp. 428-438
Author(s):  
Sigong Zhang ◽  
Ying Hei Chui ◽  
David Joo
Keyword(s):  
Load Transfer ◽  
Mechanical Performance ◽  
Small Scale ◽  
Construction Time ◽  
Plane Shear ◽  
Floor Systems ◽  
Diaphragm Action ◽  
Wood Frame ◽  
Strength And Stiffness ◽  
Frame Construction

Abstract Panelized light wood frame construction is becoming more popular due to the faster construction time and shortage of onsite skilled labor. To use light wood frame panels effectively in panelized floor systems, panel-to-panel joints must be fastened adequately to allow load transfer between panels. They must also possess in-plane shear strength and stiffness comparable to stick-built, staggered-sheathed assemblies. This study was designed to develop efficient and effective panel-to-panel joints for connecting adjacent floor panels built with wood I-joists and evaluate the efficiency of the joints in achieving diaphragm action. At first, a number of these panel-to-panel joints were tested in the laboratory using a small-scale diaphragm test setup to determine their efficiency in transferring in-plane forces between panels. Test results showed that a small decrease in in-plane stiffness was expected for the most effective joints, but their strengths were significantly higher than at the same location in a conventional site-built floor diaphragm. The presence of blockings and use of two-row nailing were found to considerably improve stiffness and strength. These features can be used to mitigate the potential reduction in mechanical performance of panelized floor construction, in comparison with the site-built wood I-joist floor.

Experimental testing of open pit dump trucks in operating conditions

2020 ◽  
pp. 530-542
Author(s):  
A. G. Zhuravlev ◽  
M. V. Isakov
Keyword(s):  
Power Plants ◽  
Experimental Testing ◽  
Operating Conditions ◽  
Open Pit ◽  
Dump Truck ◽  
Experimental Measurements ◽  
Complex Data ◽  
Special Unit ◽  
Operating Modes ◽  
Dump Trucks

The high importance of optimizing the operation of quarry transport is confirmed by the leading share of its costs in the total cost of mining. The current direction of optimization is the development and implementation of digital technologies for processing complex data on the parameters of transport vehicles. The solution of the above issues should be based on the results of scientific research on the collection and processing of information. Developed a set of techniques to perform experimental measurements of working parameters of mining dump trucks as part of a special unit experiments, and long monitoring measurements. A set of equipment for performing experimental measurements, as well as its installation on a dump truck is presented. The data of experimental measurements and a methodical approach to their analysis are presented. In particular, it shows the identification of operating modes of the power plant and the construction of the load diagram, the identification of elements of the transport cycle, etc. The approach to substantiation of innovative designs of power plants adapted to the conditions of a particular quarry is shown on the example of calculated schedules of energy consumption and reserve of recovery of braking energy. The proposed hardware-methodical complex is a research model for the development of methods for automated data collection and processing in the formation of elements of digital mining production.

scholarly journals Evaluation of vehicle lightweighting to reduce greenhouse gas emissions with focus on magnesium substitution

2018 ◽  
Vol 16 (6) ◽  
pp. 869-888 ◽  
Author(s):  
Siddharth Kulkarni ◽  
David John Edwards ◽  
Erika Anneli Parn ◽  
Craig Chapman ◽  
Clinton Ohis Aigbavboa ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Fuel Economy ◽  
Internal Combustion Engines ◽  
Mechanical Performance ◽  
Material Design ◽  
Torsional Stiffness ◽  
Gas Emissions ◽  
Content Type

Purpose Vehicle weight reduction represents a viable means of meeting tougher regulatory requirements designed to reduce fuel consumption and control greenhouse gas emissions. This paper aims to present an empirical and comparative analysis of lightweight magnesium materials used to replace conventional steel in passenger vehicles with internal combustion engines. The very low density of magnesium makes it a viable material for lightweighting given that it is lighter than aluminium by one-third and steel by three-fourth. Design/methodology/approach A structural evaluation case study of the “open access” Wikispeed car was undertaken. This included an assessment of material design characteristics such as bending stiffness, torsional stiffness and crashworthiness to evaluate whether magnesium provides a better alternative to the current usage of aluminium in the automotive industry. Findings The Wikispeed car had an issue with the rocker beam width/thickness (b/t) ratio, indicating failure in yield instead of buckling. By changing the specified material, Aluminium Alloy 6061-T651 to Magnesium EN-MB10020, it was revealed that vehicle mass could be reduced by an estimated 110 kg, in turn improving the fuel economy by 10 per cent. This, however, would require mechanical performance compromise unless the current design is modified. Originality/value This is the first time that a comparative analysis of material substitution has been made on the Wikispeed car. The results of such work will assist in the lowering of harmful greenhouse gas emissions and simultaneously augment fuel economy.

A Proximally-Adjustable Variable Length Intramedullary Nail: Ex Vivo Quasi-Static and Cyclic Loading Evaluation

2017 ◽  
Vol 11 (4) ◽  
Author(s):  
Mark J. Hedgeland ◽  
Alexander Martin Clark ◽  
Mario J. Ciani ◽  
Arthur J. Michalek ◽  
Laurel Kuxhaus
Keyword(s):  
Cyclic Loading ◽  
Mechanical Performance ◽  
Ex Vivo ◽  
Healing Process ◽  
Axial Loading ◽  
Torsional Stiffness ◽  
Axial Stiffness ◽  
Four Point Bending ◽  
Point Bend ◽  
Static And Cyclic Loading

An adjustable-length intramedullary (IM) nail may reduce both complications secondary to fracture fixation and manufacturing costs. We hypothesized that our novel nail would have suitable mechanical performance. To test this hypothesis, we manufactured three prototypes and evaluated them in quasi-static axial compression and torsion and quasi-static four-point bending. Prototypes were dynamically evaluated in both cyclic axial loading and four-point bending and torsion-to-failure. The prototypes exceeded expectations; they were comparable in both quasi-static axial stiffness (1.41 ± 0.37 N/m in cervine tibiae and 2.30 ± 0.63 in cadaver tibiae) and torsional stiffness (1.05 ± 0.26 N·m/deg in cervine tibiae) to currently used nails. The quasi-static four-point bending stiffness was 80.11 ± 09.360, greater than reported for currently used nails. A length-variance analysis indicates that moderate changes in length do not unacceptably alter bone-implant axial stiffness. After 103,000 cycles of axial loading, the prototype failed at the locking screws, comparable to locking screw failures seen clinically. The prototypes survived 1,000,000 cycles of four-point bend cyclic loading, as indicated by a consistent phase angle throughout cyclic loading. The torsion-to-failure test suggests that the prototype has adequate resistance to applied torques that might occur during the healing process. Together, these results suggest that our novel IM nail performs sufficiently well to merit further development. If brought to market, this adjustable-length IM nail could reduce both patient complications and healthcare costs.

The Optimization Design of the Cross-Sectional Layout of an Umbilical Based on the Hybrid Genetic Algorithm

2021 ◽  
Author(s):  
Xu Yin ◽  
Zhixun Yang ◽  
Dongyan Shi ◽  
Jun Yan ◽  
Lifu Wang ◽  
...  
Keyword(s):  
Genetic Algorithm ◽  
Cross Sections ◽  
Optimization Design ◽  
Mechanical Performance ◽  
Fitness Function ◽  
Hybrid Genetic Algorithm ◽  
Optimization Strategy ◽  
Cross Sectional ◽  
Great Probability ◽  
The Cross

Abstract The umbilical which consists of hydraulic tubes, electrical cables and optical cables is a key equipment in the subsea production system. Each components perform different physical properties, so different cross-sections will present different geometrical characteristic, carrying capacities, the cost and the ease of manufacture. Therefore, the cross-sectional layout design of the umbilical is a typical multi-objective optimization problem. A mathematical model of the cross-sectional layout considering geometric and mechanical properties is proposed, and the genetic algorithm is introduced to copy with the optimization model in this paper. A steepest descent operator is embedded into the basic genetic algorithm, while the appropriate fitness function and the selection operator are advanced. The optimization strategy of the cross-sectional layout based on the hybrid genetic algorithm is proposed with the fast convergence and the great probability for global optimization. Finally, the cross-section of an umbilical case is performed to obtain the optimal the cross-sectional layout. The geometric and mechanical performance of results are compared with the initial design, which verify the feasibility of the proposed algorithm.

Evaluation of mechanical performance and optimization design for lattice girders

2019 ◽  
Vol 87 ◽  
pp. 100-111 ◽  
Author(s):  
Wenge Qiu ◽  
Feng Lu ◽  
Gang Wang ◽  
Guang Huang ◽  
Huijian Zhang ◽  
...  
Keyword(s):  
Optimization Design ◽  
Mechanical Performance
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