Numeričko modeliranje energetski učinkovitih prozora

master's thesis

• Title (english): Numerical modelling of energy efficient windows
• Author: Luka Gojanović-Rakić
• Mentor: Bojan Milovanović (mentor)
• Committee member: Marija Jelčić Rukavina (predsjednik povjerenstva)
• Committee member: Bojan Milovanović (član povjerenstva)
• Committee member: Ana Baričević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Civil Engineering; (Materials); Zagreb
• Defense date and country: 2025-02-27, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Civil Engineering

Abstract

Cilj ovog rada je numeričko modeliranje visokokvalitetnog aluminijskog prozora s prekidom toplinskog mosta i troslojnim IZO staklom. Izračun koeficijenta prolaska topline proveden je za prozore različitih dimenzija, uzimajući u obzir utjecaj linijskih toplinskih mostova, kako bi se dobivene vrijednosti mogle usporediti.
U teorijskom dijelu rada obrađuju se ključni aspekti toplinske izolacije prozorskih sustava, naglašavajući povećanje toplinskog toka kroz konstrukciju u njihovom području. Detaljno su objašnjeni sastavni dijelovi prozora, kao i procesi proizvodnje i ugradnje koji utječu na njegova izolacijska svojstva.
Eksperimentalni dio rada prikazuje presjeke i detalje prozorskog okvira te ostakljenja, pridržavajući se smjernica norme HRN EN ISO 10077-1 (Toplinska svojstva prozora, vrata i zaslona – Proračun koeficijenta prolaska topline – 1. dio: Općenito) koji definira način izračuna koeficijenta prolaska topline prozora (Uw). Norma nalaže da se Uw vrijednost računa prema formuli: 𝑈𝑤= Σ𝐴𝑔𝑈𝑔+ Σ𝐴𝑓𝑈𝑓+ Σ𝑙𝑔𝛹𝑔+ Σ𝑙𝑔𝑏𝛹𝑔𝑏𝐴𝑓+ 𝐴𝑔
Proučavanjem dostupne literature prikazan je proračun svakog od parametara potrebnog za dobivanje gore prikazane vrijednosti. Analiza parametara provedena je prema relevantnim normama, uključujući HRN EN ISO 10077-2 (Toplinska svojstva prozora, vrata i zaslona – 2. dio: Numerička metoda za okvire) za okvir te HRN EN 673 (Staklo u graditeljstvu – Određivanje koeficijenta prolaska topline) za ostakljenje. Kvantificirani utjecaj linijskih toplinskih mostova određen je prema normi HRN EN ISO 10077-1.
Rezultat rada su dobivene vrijednosti koeficijenta prolaska topline okvira i prozorskog elementa te analiza čimbenika koji najviše utječu na vrijednosti. Zaključno su predložene mjere poboljšanja toplinskih svojstava okvira i prozora s ciljem povećanja energetske učinkovitosti.

Abstract (english)

The aim of this paper is to perform numerical modeling of a high-quality aluminum window with a thermal break and triple-glazed insulating glass. The calculation of the thermal transmittance coefficient was conducted for windows of various dimensions, taking into account the influence of linear thermal bridges to enable comparison of the obtained values.
The theoretical part of the paper addresses key aspects of thermal insulation in window systems, emphasizing the increase in heat flow through the structure in their respective areas. It provides a detailed explanation of the window’s components, as well as the manufacturing and installation processes that affect its insulation properties.
The experimental part of the paper presents cross-sections and details of the window frame and glazing, adhering to the guidelines of the HRN EN ISO 10077-1 standard (Thermal performance of windows, doors and shutters – Calculation of thermal transmittance – Part 1: General), which defines the method for calculating the window's thermal transmittance coefficient (Uw). The standard specifies that the Uw value is calculated using the following formula: 𝑈𝑤= Σ𝐴𝑔𝑈𝑔+ Σ𝐴𝑓𝑈𝑓+ Σ𝑙𝑔𝛹𝑔+ Σ𝑙𝑔𝑏𝛹𝑔𝑏𝐴𝑓+ 𝐴𝑔
By studying the available literature, the calculation of each parameter required to obtain the previously presented value is demonstrated. The parameter analysis was conducted in accordance with relevant standards, including HRN EN ISO 10077-2 (Thermal performance of windows, doors and shutters – Part 2: Numerical method for frames) for the frame and HRN EN 673 (Glass in building – Determination of thermal transmittance) for the glazing. The quantified impact of linear thermal bridges was determined according to the HRN EN ISO 10077-1 standard.
The results of the study include the obtained thermal transmittance coefficient values for the frame and the entire window element, along with an analysis of the factors that have the most significant influence on these values. Finally, measures for improving the thermal performance of the frame and window have been proposed to enhance energy efficiency.

• Keywords: Numeričko modeliranje; aluminijski prozor; troslojno ostakljenje; koeficijent prolaska topline; linijski toplinski most.
• Keywords (english): Numerical modeling; aluminum window; triple glazing; thermal transmittance coefficient; linear thermal bridge.
• Language: croatian
• URN:NBN: urn:nbn:hr:237:715522
• Study programme: Title: Civil Engineering; specializations in: Construction Management, Transportation Engineering, Geotechnical Engineering, Hydraulic Engineering, Structural Engineering, Construction Materials, Theory and Modeling of Structures; Course: Construction Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka građevinarstva (magistar/magistra inženjer/inženjerka građevinarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2025-03-12 11:36:44