Utvrđivanje utjecaja temperature na pomake izvora zračenja u CT skeneru

master's thesis

• Title (english): Determination of temperature induced X-ray source shifts in a CT scanner
• Author: Maša Milanović-Litre
• Mentor: Marko Katić (mentor)
• Mentor: Martina Rauch (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2024-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Rendgenska računalna tomografija se sve više koristi za dimenzionalna mjerenja predmeta složene geometrije. Međutim, točnost rezultata CT mjerenja može biti pod utjecajem različitih čimbenika, uključujući temperaturnu i mehaničku stabilnost uređaja.
U ovom radu istražen je utjecaj temperature na pomake izvora zračenja u CT uređaju. Prikupljeni su rezultati mjerenja temperatura na kritičnim lokacijama u CT uređaju, kao i temperature rashladne smjese koja cirkulira kroz sustav. Na temelju tih podataka izračunati su toplinski tokovi koji se odvode iz sustava.
Pomak izvora zračenja mjeren je korištenjem induktivnih ticala i praćenjem pomaka projekcije etalona, te su postavljeni pojednostavljeni matematički izrazi pomoću kojih je izračunat pomak projekcije na detektoru. Na kraju je prikazan odnos promjene temperature izvora zračenja i promjene pomaka izvora, kao i usporedba dva načina mjerenja pomaka (ticalima i radiografski).

Abstract (english)

X-ray computed tomography (XCT) is increasingly used for dimensional measurements of
complex geometry objects. However, the accuracy of CT measurement results can be
influenced by various factors, including the temperature and mechanical stability of the scanner.
This thesis investigates the impact of temperature on radiation source displacements in a CT
scanner. Temperature measurements were collected at critical locations within the CT scanner,
as well as the temperature of the coolant circulating through the system. Based on this data, the
thermal fluxes dissipated by the system were calculated.
The displacement of the radiation source was measured using inductive probes and by tracking
the displacement of the reference projection. Simplified mathematical expressions were
formulated to calculate the displacement of the projection on the detector. Finally, the
correlation between displacement changes of the source and measured temperatures was
presented, as well as a comparison of the two techniques of measuring displacement (probes
and radiographically).

• Keywords: rendgenska računalna tomografija; dimenzionalna stabilnost; CT uređaj; mjerenja temperature; dimenzionalno mjeriteljstvo
• Keywords (english): X-ray computed tomography; dimensional stability; CT scanner; temperature measurement; length metrology
• Language: croatian
• URN:NBN: urn:nbn:hr:235:419702
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-07-14 21:47:35