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Dynamic reliability assessment of a complex recovery system using fault tree, fuzzy inference and discrete event simulation

Nobakhti Abolghasem, Raissi Sadigh, Damghani Kaveh Khalili, Soltani Roya

Eksploatacja i Niezawodność

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2021

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Vol. 23, no. 4

593--604

EN

Any failure on the recovery system will cause a lot of environmental damage as well as energy loss. Hereof two types of alternatives; fast opening valve system (FOVS) and seal drum system (SDS) may be installed. The focus of this article is on the decision stage to choose the most preferred option in terms of reliability assessment. The major challenge in the research problem is on changing the pressure and temperature during operational cycles, which significantly affect the reliability. In addition, the lack of historical data complicates the reliability assessment method. Hence, we proposed a hybrid approach using fault tree analysis (FTA) and the Mamdani fuzzy inference to estimate reliability response as a function of a few frequently operating pressure and temperature. Also, discrete-event simulation helped us to evaluate the system reliability at different operating conditions. The comparisons reveals that the FOVs outperforms on average of 22.4% than the SDS and it is recommended for putting into practice for purchasing.

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Analiza niezawodności systemu grawitacyjnego chłodzenia reaktora typu ESBWR

Kaszko A., Niewiński G., Stępień M.

Aparatura Badawcza i Dydaktyczna

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2017

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T. 22, nr 3

191--198

PL

Celem niniejszej pracy jest przedstawienie metodologii analizy PSA, która jest wymagana przez Prawo Atomowe dla nowo powstających obiektów jądrowych, oraz zaprezentowanie metody drzew błędów, za pomocą, których zostało określone prawdopodobieństwo niedostępności systemu grawitacyjnego chłodzenia reaktora (GDCS) elektrowni typu ESBWR zaprojektowanej przez GE Hitachi. Praca ta obejmuje utworzenie drzewa uszkodzeń i wykonanie analizy ilościowej w programie SAPHIRE oraz oszacowanie niepewności za pomocą metody Monte Carlo. Wykazano, że w prawdopodobieństwie awarii pojedynczej linii GDCS (PLINE-A) największy wkład wnosiły zdarzenia podstawowe związane z zaworami serwisowymi.

EN

The purpose of this work is to present a methodology of PSA analysis that is required by the Polish Atomic Law for newly emerging nuclear facilities, and to show a fault tree method by which the probability of unavailability was calculated for a gravity driven cooling system (GDCS) of ESBWR type nuclear power plant designed by GE Hitachi. This work includes creating a fault tree and performing quantitative analysis in SAPHIRE program and estimating uncertainty using the Monte Carlo method. It has been shown, that in the probability of the single line fault scenario of the GDCS System, main component is the basic risk related with the services valves.

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Fault Tree Analysis as a tool for modelling the marine main engine reliability structure

Laskowski R.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2015

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nr 41 (113)

71-77

EN

The introduction to the Fault Tree Analysis has been presented in this article. Selected publications on the Fault Tree Analysis have been listed. The usefulness of the method in marine engineering application has been indicated. Reliability testing facility has been presented, that is typical two-stroke, slow-speed ship crosshead Diesel engine intended to power the ship. The way of creating system model with the Fault Tree Analysis application has been presented. Reliability structure of tested engine has been modelled using Reliability Block Diagrams, as well as the Fault Tree Analysis. Main tree describing the object reliability structure analysis and the sub-tree structure modelling crank system, subsystem of the cam shaft, cylinder exemplary system and turbocharger have been built. Qualitative analysis of the tree has been conducted – the minimal cut sets of the system has been determined. The directions for further research have been indicated.

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Analiza niezawodności awaryjnego odbioru ciepła powyłączeniowego w reaktorze typu PWR

Kowal K., Borysiewicz M.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2015

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nr 3

59--64

PL

Celem niniejszej pracy było określenie prawdopodobieństwa awarii pomocniczego systemu wody zasilającej reaktora typu PWR firmy Westinghouse. Obiektem referencyjnym, dla którego wykonano analizę była Elektrownia Jądrowa Surry (USA). Praca ta obejmuje utworzenie drzewa uszkodzeń i wykonanie analizy ilościowej w programie SAPHIRE oraz oszacowanie niepewności za pomocą metod Monte Carlo.

EN

The aim of this work was to assess the failure probability of the Westinghouse PWR auxiliary feedwater system (AFWS). The reference facility for which the analysis has been made was Surry Nuclear Power Plant located in the United States. This work includes AFWS fault tree development and qualitative analysis using the SAPHIRE code, as well as the uncertainty assessment by applying the Monte Carlo techniques.