APPLICATION OF INTERVAL ANALYSIS METHOD FOR DETERMINING OPERATING CHARACTERISTICS OF NPP POWER UNITS

In this paper, the interval analysis method is introduced to calculate the bounds of the structural displacement responses with small uncertain levels' parameters. This method is based on the first-order Taylor expansion and finite element method. The uncertain parameters are treated as the intervals, not necessary to know their probabilistic distributions. Through dividing the intervals of the uncertain parameters into several subintervals and applying the interval analysis to each subinterval combination, a subinterval analysis method is then suggested to deal with the structures with large uncertain levels' parameters. However, the second-order truncation error of the Taylor expansion and the linear approximation of the second derivatives with respect to the uncertain parameters, two error estimation methods are given to calculate the maximum errors of the interval analysis and subinterval analysis methods, respectively. A plane truss structure is investigated to demonstrate the efficiency of the presented method.

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An Interval Analysis for the Mesco Ductile Fracture

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.324-325.971 ◽

2006 ◽

Vol 324-325 ◽

pp. 971-974 ◽

Cited By ~ 2

Author(s):

Chang Hong Liu ◽

Hu Huang

Keyword(s):

Confidence Interval ◽

Ductile Fracture ◽

Interval Analysis ◽

Random Parameter ◽

Interval Number ◽

Experimental Results ◽

Analysis Method ◽

Fracture Characteristics ◽

Interval Analysis Method

With the concepts of the confidence interval, a random parameter can be transformed into an interval number in the mesco ductile fracture. Hence analyses of the random isolated void model can be used in the interval analysis method. Based on the macro- and mesco-experimental results of four steels, 30CrMnSiA, 40CrNiMoA, No.45 and No.20, the probabilistic fracture characteristics of the four steels are given. Finally the interval isolated void models in the four steels are discussed.

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Selective determination of thorium series nuclides, 224Ra and 228Th, in Tamagawa hot spring waters using time interval analysis method.

RADIOISOTOPES ◽

10.3769/radioisotopes.38.10_415 ◽

1989 ◽

Vol 38 (10) ◽

pp. 415-420 ◽

Cited By ~ 7

Author(s):

Tetsuo HASHIMOTO ◽

Tomoaki KUBOTA

Keyword(s):

Interval Analysis ◽

Hot Spring ◽

Time Interval ◽

Analysis Method ◽

Selective Determination ◽

Interval Analysis Method ◽

Thorium Series

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A Robust Aerodynamic Optimization Design for Airfoil Based on Interval Uncertainty Analysis Method

Volume 2: Computational Fluid Dynamics ◽

10.1115/ajkfluids2019-5426 ◽

2019 ◽

Author(s):

Xin Song ◽

Guannan Zheng ◽

Guowei Yang

Keyword(s):

Robust Optimization ◽

Interval Analysis ◽

Optimization Design ◽

Aerodynamic Force ◽

Interval Uncertainty ◽

Upper And Lower Bounds ◽

Analysis Method ◽

Geometric Uncertainties ◽

Interval Analysis Method ◽

Robust Optimization Design

Abstract Uncertainties will make aircraft deviate from the designed condition, resulting in the decrease in aerodynamic performance and even destruction. This paper presents a fast nonlinear interval analysis method considering geometric uncertainties. DFFD method is used to parameterize the airfoil shape, and the Kriging model for aerodynamic force and uncertainty variables is optimized by PSO algorithm to find the upper and lower bounds of the objective interval. The effects of geometric uncertainties on NACA0012 airfoil are analyzed using the above method. And then, a robust optimization design method is established based on the interval analysis method. FFD method is used to produce the deterministic design variables and the order relation of interval number is employed to transform the uncertain optimization to deterministic multi-objective optimization which is solved by MOPSO based on Pareto entropy. The robust optimization design is implemented for the symmetrical airfoil with the drag objective under geometric uncertainties and thickness constraint, and the results are compared with the deterministic optimization to validate the effectiveness of the developed method.

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