Reliability Analysis of a Filtering Reducer under the Discrete Space Environmental Shocks

Dynamic reliability analysis of a filtering reducer is performed by accounting for discrete shocks from the space environment. Gears are considered as the lumped mass and meanwhile the meshing between different gears is equivalent to a dynamic system consisting of springs and dampers during construction of the dynamic model. The Newmark method is employed to resolve differential equations, and then the additional acceleration could be obtained, caused by shocks to the filtering reducer. Dynamic reliability analysis is conducted with the help of the Simulink tool for the outputs. The results are hopefully useful for spacecraft mechanism design.

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Stochastic Model Bias Correction of Dynamic System Responses for Simulation-Based Reliability Analysis

Volume 2B: 41st Design Automation Conference ◽

10.1115/detc2015-46938 ◽

2015 ◽

Cited By ~ 2

Author(s):

Zhimin Xi ◽

Hao Pan ◽

Ren-Jye Yang

Keyword(s):

Stochastic Model ◽

Dynamic System ◽

Simulation Model ◽

Reliability Analysis ◽

Dynamic Model ◽

Bias Correction ◽

Simulation Models ◽

Model Bias ◽

Thermal Problem ◽

Simulation Based

Reliability analysis based on the simulation model could be wrong if the simulation model were not validated. Various model bias correction approaches have been developed to improve the model credibility by adding the identified model bias to the baseline simulation model. However, little research has been conducted for simulation models with dynamic system responses. This paper presents such a framework for model bias correction of dynamic system responses for reliability analysis by addressing three technical components including: i) a validation metric for dynamic system responses, ii) an effective approach for dynamic model bias calibration and approximation, and iii) reliability analysis considering the dynamic model bias. Two case studies including a thermal problem and a corroded beam problem are employed to demonstrate the proposed approaches for simulation-based reliability analysis.

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Fatigue Reliability Analysis of Wind Turbine Drivetrain Considering Strength Degradation and Load Sharing Using Survival Signature and FTA

Energies ◽

10.3390/en13082108 ◽

2020 ◽

Vol 13 (8) ◽

pp. 2108

Author(s):

Yao Li ◽

Caichao Zhu ◽

Xu Chen ◽

Jianjun Tan

Keyword(s):

Wind Turbine ◽

Reliability Analysis ◽

Dynamic Model ◽

Control Strategy ◽

System Reliability ◽

Strength Degradation ◽

Fatigue Reliability ◽

Dynamic Reliability ◽

Coupling Dynamic ◽

Coupling Dynamic Model

The wind turbine drivetrain suffers significant impact loads that severely affect the reliability and safety of wind turbines. Bearings and gears within the drivetrain are critical components with high repair costs and lengthy downtime. To realistically assess the system reliability, we propose to establish an electromechanical coupling dynamic model of the wind turbine considering the control strategy and environmental parameters and evaluate the system’s reliability of wind turbine drivetrain based on loads of gears and bearings. This paper focuses on the dynamic reliability analysis of the wind turbine under the control strategy and environmental conditions. SIMPACK (v9.7, Dassault Systèmes, Gilching, Germany) is used to develop the aero-hydro-servo-elastic coupling dynamic model with the full drivetrain that considers the flexibility of the tower and blade, the stochastic loads of wind and waves, gear meshing features, as well as the control strategy. The system reliability level of wind turbine drivetrain at different wind conditions is assessed using survival signature and fault tree analysis (FTA), and the influences of strength degradation of the transmission components on the system reliability are explored. Following this, the bending fatigue reliability and contact fatigue reliability concerning different wind conditions are compared in this paper. A case study is performed to demonstrate the effectiveness and feasibility of the proposed methodology.

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