Numerical evaluation of interfibre joint strength measurements in terms of three-dimensional resultant forces and moments

Abstract To estimate the thermal properties from transient data, a model is needed to produce numerical values with sufficient precision. Iterative regression or other estimation procedures must be applied to evaluate the model again and again. From this perspective, infinite or semi-infinite heat conduction problems are a challenge. Since the analytical solution usually contains improper integrals that need to be computed numerically, computer-evaluation speed is a serious issue. To improve the computation speed with precision maintained, an analytical method has been applied to three-dimensional (3D) cylindrical geometries. In this method, the numerical evaluation time is improved by replacing the integral-containing solution by a suitable finite body series solution. The precision of the series solution may be controlled to a high level and the required computer time may be minimized by a suitable choice of the extent of the finite body. The practical applications for 3D geometries include the line-source method for obtaining thermal properties, the estimation of thermal properties by the laser-flash method, and the estimation of aquifer properties or petroleum-field properties from well-test measurements. This paper is an extension of earlier works on one-dimensional (1D) and two-dimensional (2D) cylindrical geometries. In this paper, the computer-evaluation time for the finite geometry 3D solutions is shown to be hundreds of times faster than the infinite or semi-infinite solution with the precision maintained.

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A Stress Analysis and Strength Evaluation of Scarf Adhesive Joints Subjected to Static Tensile Loading

Design Engineering and Computers and Information in Engineering, Parts A and B ◽

10.1115/imece2006-14232 ◽

2006 ◽

Cited By ~ 1

Author(s):

Toshiyuki Sawa ◽

Masahiro Sasaki ◽

Yuya Hirayama

Keyword(s):

Joint Strength ◽

Three Dimensional ◽

Maximum Principal Stress ◽

Adhesive Joints ◽

Stress Distributions ◽

Principal Stresses ◽

Adhesive Properties ◽

Maximum Value ◽

Static Tensile ◽

Three Dimensional Finite Element

Scarf adhesive joints used in practice. However, the stress distributions and the joints strengths have not yet been fully elucidate. Important issues are how to determine the scarf angle in adherend and how to determine the adhesive properties. In this study, the stress distributions in scarf adhesive joints under static tensile loadings are analyzed using three-dimensional finite-element calculations. In the FEM calculations, the effects of Young's modulus of the adhesive, adhesive thickness, scarf angle of the adherend on the stress distributions at the adhesive interfaces are examined. The maximum principal stresses were calculated at every element at the interfaces. As the results, it is found that the maximum value of the maximum principal stress occurs at the edge of the adhesive interfaces (z=0, 1/s=1). It is also observed that the maximum value of the stress is the smallest, when the scarf angle is 60 degree. In addition, the joint strength is estimated using the interface stress. For the verification of the FEM calculations, the experiments were carried out to measure the strengths and the strains in the joints under static tensile loadings using strain gauges. Fairly good agreements are observed between the numerical and the measured results concerning the joint strength and the strains.

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Passive scalar diffusion in three-dimensional turbulent rectangular free jets with numerical evaluation of turbulent Prandtl/Schmidt number

International Communications in Heat and Mass Transfer ◽

10.1016/j.icheatmasstransfer.2018.03.019 ◽

2018 ◽

Vol 95 ◽

pp. 106-115 ◽

Cited By ~ 8

Author(s):

Ivan Di Venuta ◽

Andrea Boghi ◽

Matteo Angelino ◽

Fabio Gori

Keyword(s):

Numerical Evaluation ◽

Schmidt Number ◽

Three Dimensional ◽

Passive Scalar ◽

Free Jets ◽

Scalar Diffusion

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Stress Analysis and Strength of Scarf Adhesive Joints of Dissimilar Adherends Subjected to Static Bending Moments

Volume 10: Mechanics of Solids and Structures, Parts A and B ◽

10.1115/imece2007-41597 ◽

2007 ◽

Cited By ~ 1

Author(s):

Toshiyuki Sawa ◽

Atsushi Karami

Keyword(s):

Joint Strength ◽

Three Dimensional ◽

Maximum Principal Stress ◽

Adhesive Joints ◽

Bending Moments ◽

Stress Distributions ◽

Adhesive Interface ◽

Maximum Value ◽

Dimensional Finite Element ◽

Three Dimensional Finite Element

The stress distributions in scarf adhesive joints of dissimilar adherends under static bending moments are analyzed using three-dimensional finite-element calculations. The code employed is ANSYS. In FEM calculations, the effects of Young’s modulus of the adhesive, adhesive thickness, scarf angle of the adherend on the stress distributions at the adhesive interface are examined. As the results, it is found that the maximum value of the maximum principal stress occurs at the edge of the scarf adhesive interface. It is also observed that the maximum value of the stress is minimum, when the scarf angle is 60 degree. In addition, the joint strength is estimated using the obtained stress distribution. For the verification of the FEM calculations, the experiments were carried out to measure the strengths and the strains in the joints under static bending moments using strain gauges. Fairly good agreements are observed between the numerical and the measured results concerning the joint strength and the strains.

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