Stress Intensity Factor of a Circumferential Crack in a Thick-Walled Cylinder Under Thermal Striping

2002 ◽  
Author(s):  
Toshiyuki Meshii ◽  
Katsuhiko Watanabe
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Temperature Change ◽  
Crack Depth ◽  
Crack Arrest ◽  
Fluid Temperature ◽  
Circumferential Crack ◽  
Thermal Striping ◽  
Walled Cylinder

This paper tries to explain the interesting field data that indicate a surface axisymmetric circumferential crack inside a hollow cylinder (circumferential crack) shows tendency toward crack arrest, when the temperature of the fluid inside the cylinder experiences sinusoidal fluctuation (thermal striping). Maximum stress intensity factor (SIF) range of a circumferential crack in a finite-length thick-walled cylinder with rotation-restrained edges, under thermal striping, was studied for this attempt. It was assumed that the fluid temperature changes sinusoidally and that heat transfer coefficient is constant. Results showed that the maximum SIF range under thermal striping decreases monotonously when crack depth is varied to become longer than a specific value, which corresponds to the crack arrest tendency. These results are similar to those obtained for the step temperature change. Thus, characteristics obtained for the step temperature change, such as the existence of an upper limit for the normalized crack arrest depth independent of the cylinder material and fluid temperature, are valid also for thermal striping (163 words).

Stress Intensity Factor of a Circumferential Crack in a Thick-Walled Cylinder Under Thermal Striping

2004 ◽  
Vol 126 (2) ◽  
pp. 157-162 ◽  
Author(s):  
Toshiyuki Meshii ◽  
Katsuhiko Watanabe
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Crack Depth ◽  
Crack Arrest ◽  
Characteristic Change ◽  
Fluid Temperature ◽  
Circumferential Crack ◽  
Thermal Striping ◽  
Walled Cylinder

This paper tries to explain the interesting field data that indicate a surface axisymmetric circumferential crack inside a hollow cylinder (circumferential crack) shows tendency toward crack arrest, when the temperature of the fluid inside the cylinder experiences sinusoidal fluctuation (thermal striping). For this purpose, transient stress intensity factor (SIF) range of a circumferential crack in a finite-length thick-walled cylinder with rotation-restrained edges, under thermal striping, was analyzed. It was assumed that the fluid temperature changes sinusoidally and that heat transfer coefficient is constant. First an analytical temperature solution for the problem was obtained and it was combined with our SIF evaluation method derived based on superposition principle and Duhamel’s analogy. Then we defined the maximum SIF range as the maximum value of the SIF range during thermal striping and studied the characteristic change of this maximum SIF range with the variation of crack depth to explain the crack arrest tendency. Results showed that the maximum SIF range under thermal striping decreases monotonously when crack depth is varied to become deeper than a specific value, which corresponds to the crack arrest tendency.

Stress Intensity Factors of Various Surface Cracks Inside a Hollow Cylinder Under Steady State Thermal Striping

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Toshiyuki Meshii ◽  
Kentaro Shibata
Keyword(s):  
Stress Intensity Factor ◽  
Thermal Stress ◽  
Steady State ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Hollow Cylinder ◽  
Crack Depth ◽  
Surface Cracks ◽  
Paris Law ◽  
Thermal Striping

A thermal stress problem of a long hollow cylinder was considered in this paper. The outer surface of the cylinder was adiabatically insulated, and the inner surface was heated axisymmetrically by a fluid with sinusoidal temperature fluctuations (hereafter called as thermal striping), whose temperature amplitude (ΔT) and angular velocity (ω) were constant. The heat transfer coefficient h was also assumed to be constant. The stress intensity factor (SIF) due to the thermal stress for a given cylinder configuration varies not only with these three parameters ΔT, ω, and h, but also with time. The temperature and, as a result, SIF fluctuation amplitude soon became constant (Meshii, T., and Watanabe, K., 2004, “Stress Intensity Factor of a Circumferential Crack in a Thick-Walled Cylinder Under Thermal Striping,” ASME J. Pressure Vessel Technol., 126(2), pp. 157–162), which hereafter is called as steady state. If one is interested in fatigue crack growth (assuming Paris law) under this thermal stress, because the SIF range soon converges to a constant, it seemed important to know the maximum value of the steady state SIF range for a given cylinder configuration, for all possible combinations of ΔT, ω, and h. This maximum SIF evaluation is time consuming. Thus in this paper, this maximum steady state SIF range for four typical surface cracks’ deepest point, inside a hollow cylinder for all possible combinations of ΔT, ω, and h were presented as a first step. Thin-to thick-walled cylinders in the range of mean radius to wall thickness parameter rm/W=10.5–1 were considered. Crack configurations considered were 360 deg continuous circumferential, radial, semi-elliptical in the circumferential and radial directions. Normalized crack depth for all cases was in the range of a/W=0.1–0.5. In case of semi-elliptical crack, the normalized crack length a/c was all in the range of 0.063–1.

Normalized Stress Intensity Factor Solution of an Inner-Surface Circumferential Crack in Thin- to Thick-Walled Cylinder Under Thermal Striping

2003 ◽  
Author(s):  
Toshiyuki Meshii ◽  
Katsuhiko Watanabe
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Wall Thickness ◽  
Evaluation Method ◽  
Thickness Ratio ◽  
Dimensionless Parameters ◽  
Circumferential Crack ◽  
Inner Surface ◽  
Thermal Striping

In this paper we considered the normalized stress intensity factor (SIF) of an inner-surface circumferential crack in a thin- to thick-walled finite-length cylinder under thermal striping. The edges of the cylinder were rotation-restrained and the outer surface was adiabatically insulated. Inner surface of the cylinder was heated by a fluid with sinusoidal temperature fluctuation. We combined an analytical temperature solution for the problem and our SIF evaluation method for the crack, and as a result, showed that the transient SIF solution can be expressed in a generalized form by dimensionless parameters such as mean radius to wall thickness ratio, Biot number, normalized striping frequency and Fourier number. Finally, normalized SIF ranges for the 1st cycle and steady state were given for these dimensionless parameters in tables for mean radius to wall thickness ratio of 10, 5 and 1.

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