Verification test problems for the calculation of probability of loss of assured safety in temperature-dependent systems with multiple weak and strong links

Abstract

Four verification test problems are presented for checking the conceptual development and computational implementation of calculations to determine the probability of loss of assured safety (PLOAS) in temperaturedependent systems with multiple weak links (WLs) and strong links (SLs). The problems are designed to test results obtained with the following definitions of loss of assured safety: (i) Failure of all SLs before failure of any WL, (ii) Failure of any SL before failure of any WL, (iii) Failure of all SLs before failure of all WLs, and (iv) Failure of any SL before failure of all WLs. The test problems are based on assuming the same failure properties for all links, which results in problems that have the desirable properties of fully exercising the numerical integration procedures required in the evaluation of PLOAS and also possessing simple algebraic representations for PLOAS that can be used for verification of the analysis.

Effect of delayed link failure on probability of loss of assured safety in temperature-dependent systems with multiple weak and strong links.

“…[7][8][9] This presentation extends previous results by developing representations for PLOAS for the situation in which there is a delay between the time at which a link reaches its failure temperature and the time at which the link actually fails.…”

“…7 Further, two related presentations consider the verification of calculations to determine PLOAS. 8,9 A fundamental assumption in the representations for PLOAS studied in Refs. [7][8][9][10] is that a link fails instantly when it reaches its failure temperature.…”

“…8,9 A fundamental assumption in the representations for PLOAS studied in Refs. [7][8][9][10] is that a link fails instantly when it reaches its failure temperature. The purpose of this presentation is to study representations for PLOAS obtained with the assumption that there is a delay between the time when a link reaches its failure temperature and the time at which the link actually fails.…”

Effect of delayed link failure on probability of loss of assured safety in temperature-dependent systems with multiple weak and strong links

“…(2.1), Ref. [9]). Further, if CDF WL,j (t) and CDF SL,k (t) correspond to the same function p(t) for j = 1, 2, …, nWL and k = 1, 2, …, nSL…”

“…(9.3) are also presented in Ref. [9] for several additional definitions of loss of assured safety. These representations and their associated verification tests are summarized in Table 10.…”