scholarly journals METHODOLOGY OF VIBRO LOADER DESIGN WITH ASYMMETRIC OSCILLATIONS

2020 ◽  
pp. 135-142
Author(s):  
M. Gerasimov ◽  
N. Lyubimyy ◽  
V. Ryazancev
Keyword(s):  
Fourier Series ◽  
Driving Force ◽  
Driving Forces ◽  
Design Method ◽  
Road Construction ◽  
Design Stage ◽  
Multi Stage ◽  
Long Time ◽  
Vibration Mechanism ◽  
Asymmetric Oscillations

Vibration machines make up a large class of construction and road construction equipment. The improvement of vibration machines is carried out in the direction of improving the vibration device as the main working body of the machine. For a long time, vibrators with circular vibrations are used as vibration devices, the effectiveness of which is not always sufficient when performing special work on immersing piles into and removing them from the soil. The priority area of development and creation of vibration devices for technological processes in the coming years is mechanisms with asymmetric oscillations. Vibration devices with asymmetric oscillations can significantly increase the efficiency of using vibration machines due to the fact that the driving force aimed at performing useful work exceeds the magnitude of the driving force directed at idling several times. However, at present there is no method for determining and calculating the parameters of vibration devices with asymmetric oscillations instead of circular vibrators. The purpose of the article is to consider a method for designing vibrational devices with asymmetric oscillations, based on the method of expanding a given function of changing the value of the total driving force into a Fourier series, the terms of which are the values of the driving forces generated by each stage of a multi-stage vibration mechanism. The study is based on classical analytical and numerical methods. The results obtained allows to use the methodology for evaluating the design method of a vibration device with asymmetric vibrations at the design stage and to evaluate the effectiveness of the designed vibration device.

scholarly journals Proposal of a stage-by-stage design method and its application on a multi-stage multiphase pump based on numerical simulations

2021 ◽  
Vol 13 (1) ◽  
pp. 168781402098731
Author(s):  
Yi Shi ◽  
Hongwu Zhu
Keyword(s):  
Volume Fraction ◽  
Design Method ◽  
Oil Field ◽  
Stage Design ◽  
Multiphase Pump ◽  
Flow Parameters ◽  
Multi Stage ◽  
Comparison Results ◽  
Third Stage ◽  
Gas Volume

Rotodynamic multiphase pumps are usually equipped with many compression units to provide sufficient boosting pressure for the transportation of production fluid in gas oil field. It is a challenge to maintain pump performance while flow parameters in each stage vary due to the compressibility of gas-liquid phase. In this article, a stage-by-stage design method is proposed to improve the boosting capability of a multiphase pump. Variations of flow parameters in each stage are investigated based on computational fluid dynamics (CFD) numerical simulation. Available methods to determinate main impeller geometry parameters of impeller are discussed. The stage-by-stage design method is applied on a five-stage multiphase pump when the inlet gas volume fraction (GVF) are 30% and 50% separately. The second stage is modified base on its corresponding inlet flow parameters when inlet GVF is 30% while the second and third stage are modified when inlet GVF is 50%. Flow parameters, pressure distribution and velocity distribution are compared between the original pump and modified pump. Differential pressure of the modified pump increases by 53.72 kPa and 58.57 kPa respectively when inlet GVFs are 30% and 50%. The feasibility of the stage-by-stage design method is verified through the comparison results.

Application research of automobile modeling optimization design based on virtual reality technology

2021 ◽  
pp. 1-13
Author(s):  
Jingfeng Shao ◽  
Zhigang Yang
Keyword(s):  
Virtual Reality ◽  
Optimization Design ◽  
Evaluation Process ◽  
Design Stage ◽  
Virtual Reality Technology ◽  
Automobile Design ◽  
Field Of Vision ◽  
Development Cycle ◽  
Design Cycle ◽  
Long Time

Automobile styling design is an important part of the design chain. In the traditional automobile modeling evaluation, the process of project evaluation is more in-depth, and designers exchange ideas. Different designers have different evaluations of automobile styling. The evaluation process lasts a long time, which leads to the design cycle being too long and the efficiency of automobile modeling evaluation is greatly reduced. The introduction of virtual reality in automobile modeling evaluation can effectively optimize the evaluation process and promote the rapid adjustment of the model on the basis of development. From the virtual reality system based on mechanical engineering, we only need the parameters of the car model to observe the actual situation through VR technology, and use the measurement tools to directly and accurately evaluate the driver’s field of vision. Through the application of virtual reality technology in the automobile design stage, the interactive and network-based remote research on automobile modeling will also make the automobile design process more convenient, easier to communicate with designers, and reduce the development cycle and cost of automobile design.

scholarly journals Driving forces on dislocations: finite element analysis in the context of the non-singular dislocation theory

2021 ◽  
Author(s):  
Xiandong Zhou ◽  
Christoph Reimuth ◽  
Peter Stein ◽  
Bai-Xiang Xu
Keyword(s):  
Finite Element ◽  
Dislocation Loop ◽  
Driving Force ◽  
Complex Geometry ◽  
Driving Forces ◽  
Singular Solutions ◽  
Dislocation Model ◽  
Configurational Force ◽  
Element Analysis ◽  
Dislocation Configuration

AbstractThis work presents a regularized eigenstrain formulation around the slip plane of dislocations and the resultant non-singular solutions for various dislocation configurations. Moreover, we derive the generalized Eshelby stress tensor of the configurational force theory in the context of the proposed dislocation model. Based on the non-singular finite element solutions and the generalized configurational force formulation, we calculate the driving force on dislocations of various configurations, including single edge/screw dislocation, dislocation loop, interaction between a vacancy dislocation loop and an edge dislocation, as well as a dislocation cluster. The non-singular solutions and the driving force results are well benchmarked for different cases. The proposed formulation and the numerical scheme can be applied to any general dislocation configuration with complex geometry and loading conditions.

Driving forces and structural changes of China as a market provider for Korea

2018 ◽  
Vol 22 (3) ◽  
pp. 194-211 ◽  
Author(s):  
Yongqi Feng ◽  
Tianshu Zhang
Keyword(s):  
Steady State ◽  
Driving Force ◽  
Design Methodology ◽  
Structural Changes ◽  
Driving Forces ◽  
Consumption Expenditure ◽  
Input Output ◽  
Content Type ◽  
Fixed Capital Formation ◽  
The Impact

Purpose The purpose of this paper is to provide a better understanding of the driving forces and structural changes of China as a market provider for Korea. This paper gives the answers for the following questions: How do China’s final demands trigger the growth of its imports from Korea? And what’s the impact of China’s final demands on the import in different industries? Design/methodology/approach Based on the Multi-Regional Input-Output model and World Input-Output Table database, this paper constructs the non-competitive imports input-output (IO) table of China to Korea. According to this table, we can calculate the induced imports coefficient and comprehensive induced import coefficients of China’s four final demands for imports from Korea in the 56 industries in China. Findings Among the four driving forces, the strongest one is changes in inventories and valuables. The impact of final consumption expenditure and fixed capital formation is much lower than that of changes in inventories and valuables, but they have a broader impact for the 56 industries. This paper finds out the China’s import induction of the final demands to Korea peaked in 2005 and 2010 and decreased greatly in 2014, so the position of China as market provider for Korea will no longer rise substantially, contrarily it will be in a steady state. Originality/value First, this paper constructs the non-competitive IO table to analyze the market provider issues between two countries and provides practical ways and methods for studies on the issues of imports and market provider. Second, this paper investigates the different roles of four final demands on driving force of China as market provider for Korea and the structural changes of China as a market provider for Korea among 56 industries from 2000 to 2014.

Study on the Steering Performance of Dual-Motor Drive Track Bulldozer

2013 ◽  
Vol 427-429 ◽  
pp. 133-136
Author(s):  
Qiang Song ◽  
Pu Zeng
Keyword(s):  
Simulation Model ◽  
Dynamic Characteristics ◽  
Driving Force ◽  
Driving Forces ◽  
Small Radius ◽  
Motor Drive ◽  
Matlab Simulink ◽  
Simulation Results ◽  
Two Sides

The driving theory and the dynamic characteristics of small radius steering, medium radius steering and big radius steering is analyzed, and the simulation model is established under Matlab/Simulink. Then the track bulldozers steering performance of the three sheerings is simulated. The results show that, at different steering modes, the running states of the two sides driving motors are not the same, and the track driving forces of the two sides vary widely. The track driving force is great in the small radius steering model, while small in the medium and big radius steering models. The simulation results lay the foundation for dual-motor drive track bulldozers steering performance matching.

A time-varying reliability-based robust design method considering overall efficiency of axial piston pump

2021 ◽  
pp. 1748006X2110661
Author(s):  
Zunling Du ◽  
Yimin Zhang
Keyword(s):  
Energy Conversion ◽  
Robust Design ◽  
Design Method ◽  
Design Stage ◽  
Structure Parameters ◽  
Time Varying ◽  
Design Variables ◽  
Reliability Method ◽  
Overall Efficiency ◽  
Axial Piston

Axial piston pumps (APPs) are the core energy conversion components in a hydraulic transmission system. Energy conversion efficiency is critically important for the performance and energy-saving of the pumps. In this paper, a time-varying reliability design method for the overall efficiency of APPs was established. The theoretical and practical instantaneous torque and flow rate of the whole APP were derived through comprehensive analysis of a single piston-slipper group. Moreover, as a case study, the developed model for the instantaneous overall efficiency was verified with a PPV103-10 pump from HYDAC. The time-variation of reliability for the pump was revealed by a fourth-order moment technique considering the randomness of working conditions and structure parameters, and the proposed reliability method was validated by Monte Carlo simulation. The effects of the mean values and variance sensitivity of random variables on the overall efficiency reliability were analyzed. Furthermore, the optimized time point and design variables were selected. The optimal structure parameters were obtained to meet the reliability requirement and the sensitivity of design variables was significantly reduced through the reliability-based robust design. The proposed method provides a theoretical basis for designers to improve the overall efficiency of APPs in the design stage.

Roll design method using virtual flow line for multi-stage profile rolling process

2018 ◽  
Vol 32 (10) ◽  
pp. 4813-4819
Author(s):  
Hyeon-Seok Jung ◽  
Jeong-Hun Kim ◽  
Byung-Min Kim
Keyword(s):  
Flow Line ◽  
Design Method ◽  
Rolling Process ◽  
Roll Design ◽  
Multi Stage

Exploring the Design Space Using a Surrogate Model Approach With Digital Human Modeling Simulations

2018 ◽  
Author(s):  
Salman Ahmed ◽  
Mihir Sunil Gawand ◽  
Lukman Irshad ◽  
H. Onan Demirel
Keyword(s):  
Human Factors ◽  
Surrogate Model ◽  
Human Performance ◽  
Design Method ◽  
Human Subjects ◽  
Design Stage ◽  
Digital Human Modeling ◽  
Design Variables ◽  
Human Modeling ◽  
Digital Human

Computational human factors tools are often not fully-integrated during the early phases of product design. Often, conventional ergonomic practices require physical prototypes and human subjects which are costly in terms of finances and time. Ergonomics evaluations executed on physical prototypes has the limitations of increasing the overall rework as more iterations are required to incorporate design changes related to human factors that are found later in the design stage, which affects the overall cost of product development. This paper proposes a design methodology based on Digital Human Modeling (DHM) approach to inform designers about the ergonomics adequacies of products during early stages of design process. This proactive ergonomics approach has the potential to allow designers to identify significant design variables that affect the human performance before full-scale prototypes are built. The design method utilizes a surrogate model that represents human product interaction. Optimizing the surrogate model provides design concepts to optimize human performance. The efficacy of the proposed design method is demonstrated by a cockpit design study.

Inverse Design of 3D Multi-Stage Transonic Fans at Dual Operating Points

2013 ◽  
Author(s):  
James H. Page ◽  
Paul Hield ◽  
Paul G. Tucker
Keyword(s):  
Design Method ◽  
Pressure Ratio ◽  
Three Dimensional ◽  
Inverse Design ◽  
Flow Angle ◽  
Trade Offs ◽  
Multi Stage ◽  
Full Speed ◽  
Computational Fluid Dynamics Cfd ◽  
Operating Points

Semi-inverse design is the automatic re-cambering of an aerofoil, during a computational fluid dynamics (CFD) calculation, in order to achieve a target lift distribution while maintaining thickness, hence “semi-inverse”. In this design method, the streamwise distribution of curvature is replaced by a stream-wise distribution of lift. The authors have developed an inverse design code based on the method of Hield (2008) which can rapidly design three-dimensional fan blades in a multi-stage environment. The algorithm uses an inner loop to design to radially varying target lift distributions, an outer loop to achieve radial distributions of stage pressure ratio and exit flow angle, and a choked nozzle to set design mass flow. The code is easily wrapped around any CFD solver. In this paper, we describe a novel algorithm for designing simultaneously for specified performance at full speed and peak efficiency at part speed, without trade-offs between the targets at each of the two operating points. We also introduce a novel adaptive target lift distribution which automatically develops discontinuous changes of calculated magnitude, based on the passage shock, eliminating erroneous lift demands in the shock vicinity and maintaining a smooth aerofoil.

scholarly journals Common Problems and Design Methods of Urban Municipal Road Design

2017 ◽  
Vol 6 (2) ◽  
Author(s):  
Jiayi Miao
Keyword(s):  
Social Life ◽  
Driving Force ◽  
Rapid Development ◽  
Road Construction ◽  
Urban Infrastructure ◽  
Urban Transport ◽  
Urban Road ◽  
Road Design ◽  
Common Problems ◽  
China’S Economy

With the rapid development of China's economy, the construction scale of urban transport is also expanding. Among them, municipal road construction is an important part of urban infrastructure as well as an important guarantee for the development of people's livelihood; it is also an important driving force to promote urban transport system and social life development. The author expounds the importance and basic requirements of urban road designing, and discusses some common problems and countermeasures, hoping to be helpful.

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