Design optimization and dynamic analysis of a tensegrity-based footbridge

Noncontacting finger seals are new compliant seal in gas turbine engine sealing technology. Their potential hydrodynamic and hydrostatic lifting capabilities make them preferable to brush seals and contacting finger seals. The work concerns the mechanism of dynamic leakage of noncontacting finger seal, and a novel dynamic leakage analysis model is proposed. The model combines seal dynamic analysis and seal leakage analysis together to estimate seal dynamic performance through seal leakage. The nature of dynamic leakage performance affected by the change of seal–rotor clearance is revealed. Dynamic leakage increasing is mainly affected by ratio of friction force to finger stiffness, finger mass natural frequency, and rotor excitation amplitude. Results show that the leakage increasing caused by the rotor eccentricity is inevitable. In the design optimization of the noncontacting finger seal, the ratio of friction force to finger stiffness and the rotor excitation should be as small as possible, and the finger natural frequency should be as large as possible.

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Design optimization with computational fluid dynamic analysis of β-type Stirling engine

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2016.10.063 ◽

2017 ◽

Vol 113 ◽

pp. 87-102 ◽

Cited By ~ 33

Author(s):

Gang Xiao ◽

Umair Sultan ◽

Mingjiang Ni ◽

Hao Peng ◽

Xin Zhou ◽

...

Keyword(s):

Dynamic Analysis ◽

Design Optimization ◽

Computational Fluid Dynamic ◽

Fluid Dynamic ◽

Stirling Engine ◽

Computational Fluid Dynamic Analysis

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Modelling and Control of PKM in an Integrated Environment

Volume 1: 23rd Computers and Information in Engineering Conference, Parts A and B ◽

10.1115/detc2003/cie-48178 ◽

2003 ◽

Author(s):

Dan Zhang ◽

Lihui Wang ◽

Sherman Y. T. Lang

Keyword(s):

Remote Control ◽

Dynamic Analysis ◽

Design Optimization ◽

Dynamic Modeling ◽

Visual Environment ◽

Integrated Environment ◽

Kinetostatic Model ◽

And Control

This paper introduces an integrated validation system that consists of the following modular components: kinematic/dynamic analysis module, kinetostatic model, CAD module, FEM module, CAM module, optimization module and visual environment for remote control. In this paper, authors focus mainly on the modules of kinetostatic modeling, dynamic modeling, PKM design optimization, and remote control realization. The prototype of a 3-dof PKM developed at NRC-IMTI is used as an example throughout this paper.

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Dynamic Analysis and Design Optimization of a Drag-Based Vibratory Swimmer

Fluids ◽

10.3390/fluids5010038 ◽

2020 ◽

Vol 5 (1) ◽

pp. 38

Author(s):

Sevak Tahmasian ◽

Arsam Jafaryzad ◽

Nicolas L. Bulzoni ◽

Anne E. Staples

Keyword(s):

Dynamic Analysis ◽

Design Optimization ◽

Hydrodynamic Forces ◽

The Body ◽

Floating Body ◽

Design And Optimization ◽

Analysis And Design ◽

Drag Forces ◽

The One ◽

Time Periodic

Many organisms achieve locomotion via reciprocal motions. This paper presents the dynamic analysis and design optimization of a vibratory swimmer with asymmetric drag forces and fluid added mass. The swimmer consists of a floating body with an oscillatory mass inside. One-dimensional oscillations of the mass cause the body to oscillate with the same frequency as the mass. An asymmetric rigid fin attached to the bottom of the body generates asymmetric hydrodynamic forces, which drive the swimmer either backward or forward on average, depending on the orientation of the fin. The equation of motion of the system is a time-periodic, piecewise-smooth differential equation. We use simulations to determine the hydrodynamic forces acting on the fin and averaging techniques to determine the dynamic response of the swimmer. The analytical results are found to be in good agreement with vibratory swimmer prototype experiments. We found that the average unidirectional speed of the swimmer is optimized if the ratio of the forward and backward drag coefficients is minimized. The analysis presented here can aid in the design and optimization of bio-inspired and biomimetic robotic swimmers. A magnetically controlled microscale vibratory swimmer like the one described here could have applications in targeted drug delivery.

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