PSI - Issue 60

A. Syed et al. / Procedia Structural Integrity 60 (2024) 195–202 A. Syed/ StructuralIntegrity Procedia 00 (2023) 000 – 000

200

6

Critical damage parameter (Dc = 0.12)

0.14

0.12

0.10

0.08

0.06

0.04

0.02

Damage parameter (D)

0.00

0

10

20

30

40

50

60

Time (s)

Fig. 3 : Variation of damage parameter (D) with time for internal pressure of 2.1 MPa applied to the clad tubes.

Using the developed critical material damage parameter, the analysis was carried out for various internal pressure ranging from 0.3 MPa to 10 MPa at constant heating rates. The time and temperature taken by the clad tube to reach the critical damage parameter is noted. The variation of damage parameter with time under different internal pressure is shown in Fig. 4. It can be seen that the burst temperature decreases with increase in internal pressure as shown in Fig. 5. The value of burst temperature data obtained through analysis is fitted with exponential curve. Equation of the fitted curve is shown in Eq. (3). It can be observed that exponential fitted curve matches well with the burst temperature data. = ∗ exp (− ) + (3) where ‘T b ’ is burst temperature (in °C), ‘P’ is internal pressure (in MPa), a, b and c are material constant with value of 486, 3.2 and 560 respectively. In order to find out the value of burst temperature at any instant of pressure, Eq. (3) can be used. After obtaining the burst temperature, the time for the burst of the clad tube can be obtained.

0.15

Critical damage parameter (Dc = 0.12)

0.12

Internal pressure (MPa) 0.3 0.8

0.09

0.06

2 5 10

0.03

0.00 Damage parameter (D)

0

10 20 30 40 50 60

Time (s)

Fig. 4 : Variation of damage parameter (D) with time for different values of internal pressure applied to the clad tubes.