Estimation of collapse moment for the wall-thinned pipe bends using fuzzy model identification

In this work, the collapse moment due to wall-thinned defects is estimated through fuzzy model identification. A subtractive clustering method is used as the basis of a fast and robust algorithm for identifying the fuzzy model. The fuzzy model is optimized by a genetic algorithm combined with a least squares method. The developed fuzzy model has been applied to the numerical data obtained from the finite element analysis. Principal component analysis is used to preprocess the input signals into the fuzzy model to reduce the sensitivity to the input change and the fuzzy model are trained by using the data set prepared for training (training data) and verified by using another data set different (independent) from the training data. Also, three fuzzy models are trained, respectively, for three data sets divided into the three classes of extrados, intrados, and crown defects, which is because they have different characteristics. The relative root mean square (RMS) errors of the estimated collapse moment are 0.5397% for the training data and 0.8673% for the test data. It is known from this result that the fuzzy models are sufficiently accurate to be used in the integrity evaluation of wall-thinned pipe bends and elbows.

[1]  Michio Sugeno,et al.  Fuzzy identification of systems and its applications to modeling and control , 1985, IEEE Transactions on Systems, Man, and Cybernetics.

[2]  D N Moreton,et al.  Piping elbows with cracks Part 2: Global finite element and experimental plastic loads under opening bending , 2000 .

[3]  Man Gyun Na Design of a genetic fuzzy controller for the nuclear steam generator water level control , 1998 .

[4]  D. E. Goldberg,et al.  Optimization and Machine Learning , 2022 .

[5]  Junghui Chen,et al.  Mixture Principal Component Analysis Models for Process Monitoring , 1999 .

[6]  Eric B. Bartlett,et al.  Nuclear power plant status diagnostics using an artificial neural network , 1992 .

[7]  Jie Lin,et al.  Nuclear power plant transient diagnostics using artificial neural networks that allow 'don't-know' classifications , 1995 .

[8]  Liang Tian,et al.  Evolutionary neural network modeling for software cumulative failure time prediction , 2005, Reliab. Eng. Syst. Saf..

[9]  J. Chattopadhyay,et al.  The effect of internal pressure on in-plane collapse moment of elbows , 2002 .

[10]  Lixin Yu,et al.  Elbow stress indices using finite element analysis , 1998 .

[11]  Uday B. Desai,et al.  Improving performance in pulse radar detection using Bayesian regularization for neural network training , 2004, Digit. Signal Process..

[12]  Man Gyun Na,et al.  An Input Feature Selection Method Applied to Fuzzy Neural Networks for Signal Estimation , 2001 .

[13]  Donald Mackenzie,et al.  Plastic collapse of pipe bends under combined internal pressure and in-plane bending , 2005 .

[14]  Belle R. Upadhyaya,et al.  Sensor monitoring using a fuzzy neural network with an automatic structure constructor , 2003 .

[15]  D. E. Goldberg,et al.  Genetic Algorithms in Search , 1989 .

[16]  Melanie Mitchell,et al.  An introduction to genetic algorithms , 1996 .

[17]  Robert E. Uhrig,et al.  Signal Validation Using an Adaptive Neural Fuzzy Inference System , 1997 .

[18]  P. F. Fantoni A NEURO-FUZZY MODEL APPLIED TO FULL RANGE SIGNAL VALIDATION OF PWR NUCLEAR POWER PLANT DATA , 2000 .

[19]  Soon Heung Chang,et al.  OPTIMAL FUEL LOADING PATTERN DESIGN USING AN ARTIFICIAL NEURAL-NETWORK AND A FUZZY RULE-BASED SYSTEM , 1993 .

[20]  Maher Y. A. Younan,et al.  Limit Loads for Pipe Elbows Subjected to In-Plane Opening Moments and Internal Pressure , 1999 .

[21]  Ebrahim H. Mamdani,et al.  An Experiment in Linguistic Synthesis with a Fuzzy Logic Controller , 1999, Int. J. Hum. Comput. Stud..

[22]  Enrico Zio,et al.  Fault Diagnosis Via Neural Networks: The Boltzmann Machine , 1994 .

[23]  Soon Heung Chang,et al.  Identification of reactor vessel failures using spatiotemporal neural networks , 1996 .

[24]  D N Moreton,et al.  Piping elbows with cracks Part 1: A parametric study of the influence of crack size on limit loads due to pressure and opening bending , 2000 .

[25]  R. F. Li,et al.  Combining Conceptual Clustering and Principal Component Analysis for State Space Based Process Monitoring , 1999 .

[26]  Stephen L. Chiu,et al.  Fuzzy Model Identification Based on Cluster Estimation , 1994, J. Intell. Fuzzy Syst..