Simulating the expansion process of intumescent coating fire protection
Başlık çevirisi mevcut değil.
- Tez No: 402335
- Danışmanlar: PROF. YONG C. WANG, DR. BENEDICT ROGERS
- Tez Türü: Doktora
- Konular: İnşaat Mühendisliği, Civil Engineering
- Anahtar Kelimeler: Belirtilmemiş.
- Yıl: 2015
- Dil: İngilizce
- Üniversite: The University of Manchester
- Enstitü: Yurtdışı Enstitü
- Ana Bilim Dalı: İnşaat Mühendisliği Ana Bilim Dalı
- Bilim Dalı: Belirtilmemiş.
- Sayfa Sayısı: 201
Özet
Özet yok.
Özet (Çeviri)
The expansion ratio (defined as the ratio of the expanded thickness to the original thickness) of intumescent coatings is the most important quantity that determines their fire protection performance. This thesis explores two possible methods of predicting intumescent coating expansion: an analytical method, and a detailed numerical simulation method using Smoothed Particle Hydrodynamics (SPH). The analytical method is based on a cell-model and predicts bubble growth due to pressure increase in viscous liquid with constant viscosity. It has been extended to non-uniform temperature field and temperature-dependent viscosity of intumescent melt. Accuracy of this extended analytical method is assessed by comparison against the cone calorimeter and furnace fire tests on intumescent coating protected steel plates with different intumescent coating thicknesses, steel plate thicknesses, and heating conditions. The extended analytical method is then used to investigate how intumescent coating expansion and intumescent coating effective thermal conductivity are affected by changing the coating thickness, the steel thickness and the fire condition (including smouldering fire). The main conclusion is that the expansion ratio decreases as the rate of heating increases. Therefore, the intumescent coating properties obtained from the Standard fire exposure may be safely used for slower realistic fires, but would produce unsafe results for faster fires. The second method explores the potential of a meshless numerical simulation: Smoothed Particle Hydrodynamics (SPH). SPH modelling of intumescent coating expansion has been implemented using the SPHysics FORTRAN open-source code as a platform. To check the validity of this modelling method, the modelling results are compared against theoretical solutions for surface tension (Young-Laplace theorem), and available numerical and analytical solutions for bubble expansion. A new algorithm for representing the mass transfer of gas into the bubble using SPH particle insertion and particle shifting scheme is presented to simulate the bubble expansion process. Close agreement with an analytical solution for the initial bubble expansion rate computed by SPH is obtained. Whilst this research has demonstrated the potential of using SPH to numerically simulate intumescent coating expansion, it has also revealed significant challenges that should be overcome to make SPH a feasible method to simulate intumescent coating expansion. The main challenges include: Simulating gas-polymer flows when expansion is occurring where there are vastly different properties of these two fluids with a density ratio of about 1000. This high density ratio may easily cause numerical pressure noise, especially at the liquid-gas interface. Extremely high computational cost necessary to achieve sufficient accuracy by using a large number of particles (higher resolution), especially for the multiphase SPH program, and very small time step for the lighter fluid (air). The behaviour of intumescent coatings involves expansion ratios on the order of 10-100 with thousands of bubbles which grow, merge and burst. Based on the results of this exploratory research, future improvements are outlined to further develop the SPH simulation method.
Benzer Tezler
- Jenerik denizaltı geometrisinin katsayı tabanlı manevrakarakteristiklerinin had ve analitik çözüm yöntemleri ile analizi
Analysis of coefficient-based maneuvering characteristics of generic submarine geometry by CFD and analytical solution method
OĞUZHAN KIRIKBAŞ
Doktora
Türkçe
2024
Gemi Mühendisliğiİstanbul Teknik ÜniversitesiGemi İnşaatı ve Gemi Makineleri Mühendisliği Ana Bilim Dalı
PROF. DR. ŞAKİR BAL
- District-based urban sprawl monitoring and modelling using CA-Markov model: application in two mega cities
İlçe bazlı kentsel yayılma izleme ve CA-Markov model ile modelleme: iki mega şehirde uygulama
ANALI AZABDAFTARI
Doktora
İngilizce
2022
İletişim Bilimleriİstanbul Teknik Üniversitesiİletişim Sistemleri Ana Bilim Dalı
PROF. DR. AYŞE FİLİZ SUNAR
- Design, analysis, simulation and optimization of a MEMS Lorentz force magnetic field sensor for biosensing of biowarfare agents
Biyolojik savaş ajanlarının tespit uygulamaları için Lorentz kuvveti temelli manyetik alan sensörünün tasarımı, analizi, simülasyon ve optimizasyonu
EMİNE RUMEYSA YILMAZ
Yüksek Lisans
İngilizce
2018
Elektrik ve Elektronik Mühendisliğiİstanbul Teknik ÜniversitesiNanobilim ve Nanomühendislik Ana Bilim Dalı
PROF. DR. LEVENT TRABZON
- Design, methodology development and production of composite cryogenic liquid oxygen tank for space applications
Uzay uygulamalarına yönelik kompozit kriyojenik sıvı oksijen tank tasarımı, metodoloji geliştirilmesi ve üretimi
RECEP UFUK
Doktora
İngilizce
2024
Havacılık ve Uzay Mühendisliğiİstanbul Teknik ÜniversitesiMakine Mühendisliği Ana Bilim Dalı
PROF. DR. İSMAİL MURAT EREKE
DOÇ. DR. MUSTAFA ARİF KARABEYOĞLU
- İsale hatlarının 'SCADA' destekli işletimi
Operation of the main water lines by the assistance of the SCADA
ERKAN FERİK