A new inverse analysis method based on a relaxation factor optimization technique for solving transient nonlinear inverse heat conduction problems

2015 ◽  
Vol 90 ◽  
pp. 491-498 ◽  
Author(s):  
Miao Cui ◽  
Wei-wei Duan ◽  
Xiao-wei Gao
Keyword(s):  
Heat Conduction ◽  
Inverse Analysis ◽  
Optimization Technique ◽  
Inverse Heat Conduction ◽  
Analysis Method ◽  
Relaxation Factor ◽  
Inverse Heat Conduction Problems ◽  
Inverse Analysis Method

Development of Inverse Analysis Method of Heat Conduction and Thermal Stress for Elbow—Part II

2016 ◽  
Vol 138 (5) ◽  
Author(s):  
Kiminobu Hojo ◽  
Mayumi Ochi ◽  
Seiji Ioka ◽  
Shiro Kubo
Keyword(s):  
Heat Conduction ◽  
Thermal Stress ◽  
Inverse Analysis ◽  
Maximum Stress ◽  
Fluid Temperature ◽  
Inverse Heat Conduction ◽  
Analysis Method ◽  
Inner Surface ◽  
Pressure Test ◽  
Inverse Analysis Method

An inverse heat conduction analysis method for piping elbow was developed to estimate the temperature and stress distribution on the inner surface by measuring the outer surface temperature. In the paper, the accuracy for the thermal stress calculation using the inverse heat conduction analysis method was confirmed by comparing with the reference results from normal FE heat conduction and thermal stress analyses. In the case of the measured-basis fluid temperature input from a high temperature–pressure test, the inverse analysis method estimated the maximum stress change by 7% conservative comparing with the normal FE analyses.

Development of Inverse Analysis of Heat Conduction and Thermal Stress for Elbow: Part I

2013 ◽  
Author(s):  
Seiji Ioka ◽  
Shiro Kubo ◽  
Mayumi Ochi ◽  
Kiminobu Hojo
Keyword(s):  
Heat Conduction ◽  
Thermal Stress ◽  
Transfer Function ◽  
Surface Temperature ◽  
Outer Surface ◽  
Inverse Analysis ◽  
Temperature History ◽  
Analysis Method ◽  
Inner Surface ◽  
Inverse Analysis Method

Thermal fatigue may develop in piping elbow with high temperature stratified flow. To prevent the fatigue damage by stratified flow, it is important to know the distribution of thermal stress and temperature history in a pipe. In this study, heat conduction inverse analysis method for piping elbow was developed to estimate the temperature history and thermal stress distribution on the inner surface from the outer surface temperature history. In the inverse analysis method, the inner surface temperature was estimated by using the transfer function database which interrelates the inner surface temperature with the outer surface temperature. Transfer function database was calculated by FE analysis in advance. For some patterns of the temperature history, inverse analysis simulations were made. It was found that the inner surface temperature history was estimated with high accuracy.

Development of Inverse Analysis of Heat Conduction and Thermal Stress for Elbow (Part I)

2016 ◽  
Vol 138 (5) ◽  
Author(s):  
Seiji Ioka ◽  
Shiro Kubo ◽  
Mayumi Ochi ◽  
Kiminobu Hojo
Keyword(s):  
Heat Conduction ◽  
Surface Temperature ◽  
Inverse Analysis ◽  
Power Plants ◽  
Fatigue Cracking ◽  
Stratified Flow ◽  
Temperature History ◽  
Inverse Heat Conduction ◽  
Analysis Method ◽  
Inner Surface

High temperature stratified flow sometimes caused thermal fatigue cracking in power plants. To prevent fatigue damage by stratified flow, it is important to know temperature distribution history in a pipe. In this study, inverse heat conduction analysis method for an elbow model was developed to estimate the inner surface temperature from the measured outer surface temperature. In the method, the transfer function database inter-relating the inner surface temperature with the outer one was used. For several patterns of the temperature history, the inverse analysis simulations were performed and the accuracy of the estimated inner surface temperature was shown.

Estimation of Location and Size of Defects in a Solid Body via Inverse Heat Conduction Problem

2010 ◽  
Author(s):  
Hamid Fazeli ◽  
Masoud Mirzaei ◽  
Pourya Forooghi
Keyword(s):  
Heat Conduction ◽  
Objective Function ◽  
Solid Body ◽  
Inverse Analysis ◽  
Optimization Method ◽  
Inverse Heat Conduction ◽  
Inverse Algorithm ◽  
Gradient Based ◽  
Inverse Heat Conduction Problems ◽  
Biot Numbers

In the present paper, geometry specification in the inverse heat conduction problems (IHCP) is applied to detect the location and size of defect in a solid body. A crack or cavity is modeled as a supper-elliptic geometry whose parameters are estimated with inverse heat conduction problems. Both inverse analysis and gradient-based optimization method have been applied to an inverse algorithm that iteratively estimates the defect shape parameters. The inverse analysis is based on recording temperatures data on outer surface of solid domain that determines the objective function in the inverse algorithm with estimated and calculated temperatures. The employed gradient-based optimization method is constructed with the adjoint and sensitivity equations that are used to calculate the gradient of the objective function and the search step size, respectively. An unstructured grid is used and the computational domain is discretized with triangular elements. The finite element method (FEM) is employed to discretize the equations in analysis plus sensitivity and adjoint equations. The effects of different Biot numbers and noisy temperature data are investigated on inverse algorithm and the size and location of crack and complex cavity are calculated. Results show that the estimated shape has good agreement with exact shape of defect. The decrease of noisy data has improve the convergence rate and the increase of Biot numbers causes the estimated shape has the best accuracy in all cases.

Efficient Numerical Solution of Inverse Heat Conduction Problems

1995 ◽  
Author(s):  
Hans-Jürgen Reinhardt ◽  
Dinh Nho Hao
Keyword(s):  
Heat Flux ◽  
Heat Conduction ◽  
Numerical Methods ◽  
Stationary Point ◽  
Forthcoming Paper ◽  
Inverse Heat Conduction ◽  
Piecewise Constant ◽  
Numerical Tests ◽  
Inverse Heat Conduction Problems ◽  
Special Case

Abstract In this contribution we propose new numerical methods for solving inverse heat conduction problems. The methods are constructed by considering the desired heat flux at the boundary as piecewise constant (in time) and then deriving an explicit expression for the solution of the equation for a stationary point of the minimizing functional. In a very special case the well-known Beck method is obtained. For the time being, numerical tests could not be included in this contribution but will be presented in a forthcoming paper.

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