Procjena mjerne nesigurnosti ultrazvučnog mjerenja debljine stijenke

doctoral thesis

• Title (english): Measurement uncertainty estimation of the ultrasonic thickness measurement
• Author: Morana Mihaljević
• Mentor: Damir Markučič (mentor)
• Committee member: Josip Stepanić (predsjednik povjerenstva)
• Committee member: Damir Markučič (član povjerenstva)
• Committee member: Biserka Runje (član povjerenstva)
• Committee member: Željko Alar (član povjerenstva)
• Committee member: Duško Pavletić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2015-07-01, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Production Mechanical Engineering
• Universal decimal classification (UDC): 620 - Materials testing. Power stations. Economics of energy ; 669 - Metallurgy

Abstract

Kao dio upravljanja kvalitetom postrojenja i sustava često se provodi ultrazvučno mjerenje debljine (Ultrasonic Thickness Measurement, UTM) za čiju je primjenu dovoljan pristup s jedne strane mjerene komponente. Ova široko primjenjiva ultrazvučna tehnika daje kvantitativnu informaciju o debljini stijenke i kao takva pripada području mjeriteljske djelatnosti. U radu je provedeno istraživanje i karakterizacija utjecajnih faktora i značajki elemenata ultrazvučnog mjernog sustava na rezultat ultrazvučnog mjerenja debljine stijenke. Teorijskim razmatranjem i provedbom eksperimenata analizirana je značajnost utjecaja pojedinih parametara i njihovih interakcija. Primjenom planova pokusa i odgovarajuće metodologije za analizu rezultata eksperimenata stvoreni su preduvjeti za procjenu mjerne nesigurnosti rezultata ultrazvučnog mjerenja debljine stijenke. Da bi se procijenila mjerna nesigurnost, analizirani su utjecajni faktori na točnost i preciznost ultrazvučnog mjerenja debljine stijenke. Razvijen je i matematički model za procjenu mjerne nesigurnosti te je kvantificiran doprinos karakterističnih članova regresijskog modela. Temeljem provedenih istraživanja iskazana je mjerna nesigurnost rezultata mjerenja kod primjene odabranog ultrazvučnog mjernog sustava. Procjena mjerne nesigurnosti u postupku ultrazvučnog mjerenja debljine stijenke provedena je primjenom Monte Carlo simulacija (MCS).

Abstract (english)

Ultrasonic thickness measurement (UTM) is used as a part of structure and component integrity assessment. UTM requires access from one side of measured component. This widely used ultrasonic technique provides quantitative information about the material thickness so consequently, UTM belongs to a field of measurements activities. The work presents an experimental research and characterization of influential factors and characteristics of ultrasonic measurements system on ultrasonic thickness measurement results. Using theoretical and experimental analysis, a significance of influential factors and their interactions was examined. With the goal to estimate the measurement uncertainty of the ultrasonic thickness measurement, design of experiments is applied and methodology for experiment results analysis is created. In order to estimate the measurement uncertainty of ultrasonic thickness measurements, all factors that influence accuracy and precision were analysed. The mathematical model for ultrasonic thickness measurement uncertainty estimation was developed and contribution of particular parameters of regression models was quantified. The measurement uncertainty of specific ultrasonic measurement system was presented in accordance to the research. Monte Carlo simulation was used for ultrasonic thickness measurement uncertainty estimation.

• Keywords: ultrazvučno mjerenje debljine; Monte Carlo simulacija; mjerne nesigurnosti; plan pokusa
• Keywords (english): ultrasonic thickness measurement; Monte Carlo Simulation; measurement uncertainty; design of experiments
• Language: croatian
• URN:NBN: urn:nbn:hr:235:487461
• Study programme: Title: Mechanical Engineering and Naval Architecture; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje tehničkih znanosti (doktor/doktorica znanosti, područje tehničkih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-04-21 18:39:38