Article
Polymer Science
Ivana Turekova, Iveta Markova, Martina Ivanovicova, Jozef Harangozo
Summary: The experiment shows that the thickness of OSB has a significant effect on ignition time, and at high heat fluxes, the ignition times of OSB with different thicknesses are similar.
Article
Thermodynamics
Yueqiong Wu, Kuibin Zhou, Mengya Zhou, Mengyuan Huang, Chao Wang, Juncheng Jiang
Summary: A new facility was used to model the jet flame ejected from the ruptured tank, and the geometrical features of the flame and radiant heat fluxes on the tank surface were measured. Two thermal radiation models were established to predict the radiant heat flux field. The prediction of the models agreed well with the experimental measurements.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2022)
Article
Ecology
Nataliia Gerzhova, Christian Dagenais, Sylvain Menard, Pierre Blanchet, Jean Cote
Summary: The concern about the fire hazard of green roofs arises from the susceptibility of plants to burn. This study assessed the fire risk to adjacent buildings caused by radiant heat flux from fires on green roofs. The results showed that maintaining reasonably high moisture content in vegetation can greatly reduce the fire risk, especially for grass-covered roofs.
Article
Thermodynamics
Xianjia Huang, Yuhong Wang, He Zhu, Le He, Fei Tang, Jennifer Wen
Summary: The study conducted fire experiments of wall-attached fires with different aspect ratios and investigated the effect of the sidewall on flame height and radiant heat flux. Experimental results were consistent with predictions by an existing model, validating the reliability of the setup. A new model based on flame height increase and thermal radiation from the sidewall was developed to estimate radiant heat flux, with prediction error less than 15%.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Engineering, Civil
Alexander L. Brown, Jeffrey D. Engerer, Allen J. Ricks, Joshua Christian, Julius Yellowhair
Summary: Research on material response under high heat flux conditions is often limited by experimental conditions and constraints. However, new data obtained using concentrated solar energy has allowed for a focus on data repeatability, uncertainty reduction, and environment characterization to validate predictive codes. The presented data, covering a novel flux range and materials, signifies progress in the characterization of fires resulting from high flux events.
FIRE SAFETY JOURNAL
(2021)
Article
Materials Science, Multidisciplinary
Lanming Zhao, Dongxu Cao, Yong Chen, Hanru Liu, Tianchi You, Caoyue Li, Hongming Zhang
Summary: The suppression effect of water mist on the ignition and combustion process of polymethyl methacrylate under external radiant heat flux was investigated using a numerical model and theoretical simulation. Ignition time, surface temperature, heat release rate, and temperature distribution of flame central plane were obtained and compared with experimental results. The results show that water mist droplets can effectively delay the ignition time and the simulation results provide theoretical support and data reference for fire prevention and extinguishment of typical solid materials.
FRONTIERS IN MATERIALS
(2023)
Article
Engineering, Civil
Jose Rivera, Daniel San Martin, Michael Gollner, Claudio E. Torres, Carlos Fernandez-Pello
Summary: This study proposes the use of machine learning algorithms to predict the critical heat flux for ignition based on known material properties and environmental variables. The algorithms are trained using existing ignition data and validated against experimental results. The results show that the ML approach can accurately predict the critical heat flux under various conditions, making it a useful tool for evaluating new materials or configuration changes.
FIRE SAFETY JOURNAL
(2023)
Article
Forestry
Iveta Markova, Martina Ivanicova, Linda Makovicka Osvaldova, Jozef Harangozo, Ivana Turekova
Summary: This study evaluated the behavior of uncoated particleboards and OSB exposed to radiant heat, finding that heat flux significantly affected mass loss and time-to-ignition. OSB had higher ignition time and mass loss than particleboards, with thermal analysis confirming the differences in thermal decomposition temperature.
Article
Energy & Fuels
Olga Gaidukova, Pavel Strizhak
Summary: A model was developed to study the critical conditions and time characteristics of gel fuel ignition, using numerical modeling and theoretical derivation to analyze the impact of key parameters on ignition time. The accuracy and effectiveness of the model were validated by comparing theoretical results with experimental data.
Article
Construction & Building Technology
Archana P. Ambadi, Benny Raphael
Summary: This study experimentally evaluated the radiant heat reflected from light shelves and analysed the trade-off between heat transmission and light. About 5 million data points for heat flux data were collected from light shelves made of different materials. The results provide guidance for selecting materials that reduce heat transmission without significantly affecting reflected light.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Engineering, Environmental
I. S. Voytkov, R. S. Volkov, N. P. Kopylov, E. Yu Syshkina, A. Tomilin, P. A. Strizhak
Summary: Water curtains are used to shield thermal radiation from combustion sources, allowing fire containment without blocking movement. Experimental methods were used to study the absorption of heat by water curtains under different characteristics, leading to the development of a prediction model for effective shielding. This model can determine the necessary parameters of water curtains for different heat fluxes from combustion sources.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2021)
Article
Thermodynamics
Sayaka Suzuki, Samuel L. Manzello
Summary: Firebrand showers in conjunction with external radiant heat have a significant impact on fuel bed ignition. The study reveals that higher wind speeds and longer preheating times result in shorter times to ignition, and the firebrand arrival flux plays an important role in fuel bed ignition for low arrival flux values.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Marine
Gang Nam Lee, Kwang Hyo Jung, Hyung Jun Kim, Bong Ju Kim, Dae Kyeom Park, Il-Ryong Park
Summary: This study investigated the thermal characteristics of radiant heat shields on offshore structures using Computational Fluid Dynamics simulations. Reduction ratios of heat flux and temperature were obtained for different distances from the heat shield, and the results were compared with experimental data. The study also provided an empirical formula for the performance of heat shields based on the CFD results.
INTERNATIONAL JOURNAL OF NAVAL ARCHITECTURE AND OCEAN ENGINEERING
(2023)
Article
Engineering, Civil
F. Z. Sabi, S. M. Terrah, O. Mosbah, A. Dilem, N. Hamamousse, A. Sahila, O. Harrouz, H. Boutchiche, F. Chaib, N. Zekri, A. Kaiss, J. -P. Clerc, F. Giroud, D. X. Viegas
Summary: The flaming ignition properties of thin wildland porous fuels under different heat flux intensities were studied using a cone calorimeter. A model based on energy balance was found to provide a linear trend of ignition time for high heat flux intensities, but failed near threshold ignition due to the lack of explicit inclusion of volatiles emission. A new method proposed for estimating critical heat flux for ignition based on power-law behavior of ignition time was found to be smaller compared to existing literature, likely due to the probabilistic ignition behavior observed in the critical region.
FIRE SAFETY JOURNAL
(2021)
Article
Polymer Science
Ivana Turekova, Martina Ivanovicova, Jozef Harangozo, Stanislava Gaspercova, Iveta Markova
Summary: This study aims to investigate the effect of radiant heat on the surface of particle board. The results show that the thickness and heat flux density significantly affect the time to ignition and weight loss. Furthermore, increasing the distance from the radiant source leads to a decrease in the time to ignition.
Article
Thermodynamics
Yunxia Ma, Fei Liu, Honggang Pan, Hongjian Zhang, Shuxia Yan, Ailing Zhang
Summary: This paper proposes a dynamically tunable and switchable perfect infrared absorber that exhibits excellent electrical regulation performance and high absorptance. The absorption mechanism is explained using a multiple interference model, and it is proven to be polarization insensitive.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
F. J. dos Santos, G. S. M. Martins, M. Strobel, L. Beckedorff, K. V. de Paiva, J. L. G. Oliveira
Summary: This study investigates the effects of inlet conditions and plate's features on the thermal-flow performance of a gasket plate heat exchanger (GPHE) and assesses the impact of a modified tightening distance on its performance. No systematic study on the combined effects of inlet conditions and assembly accuracy on GPHE performance has been conducted before.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Alok K. Ray, Dibakar Rakshit, K. Ravi Kumar, Hal Gurgenci
Summary: The low thermal conductivity of phase change materials limits the heat transfer rate and application of latent heat storage systems. This numerical study examines the impact of two passive heat transfer enhancement techniques on the thermal performance of a latent heat storage system. The results show that the orientation and position of the heat transfer fluid tube have significant effects on the charging duration, while the discharging duration remains unchanged. The combined effect of orientation and eccentricity reduces the charging duration, but increases the discharging duration compared to the concentric domain.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Yalu Han, Yanlong Wang, Chenyang Liu, Xinmin Hu, Yin An, Zhengcai Li, Jiaxun Jiang, Lizhi Du
Summary: This paper investigates the calculation method of thermal conductivity in NAPLs-contaminated soils. By establishing NAPLs-contaminated soil models and using the Lattice Boltzmann Method (LBM) for calculation, an optimized three-dimensional model with high computational accuracy and efficiency is obtained. The study also finds that saturation and Nz parameters have a significant impact on calculation time, while the thermal conductivity of the two-dimensional model is more sensitive to anisotropy. The influence of porosity and NAPLs content on thermal conductivity should be considered during in-situ thermal desorption.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Mostafa Taha, Song Zhao, Aymeric Lamorlette, Jean-Louis Consalvi, Pierre Boivin
Summary: For the first time, large-eddy simulations (LES) of the near-field region of large-scale fire plumes were performed using a pressure-based Lattice Boltzmann method (LBM) with low-Mach number approximation. The simulations showed quantitative agreement with experimental data and were consistent with previously-published numerical studies. The study demonstrated the computational efficiency of the proposed LBM solver in tackling fire-induced flows, suggesting LBMs as a good alternative candidate for modeling fire-related problems.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Weixin Zhang, Yehang Xie, Yuqiang Ding, Zhao Liu, Zhenping Feng
Summary: This study investigated the impact of upstream slot leakage on the endwall film cooling characteristics of turbine blades. Pressure Sensitive Paint (PSP) technology was used to measure the film cooling characteristics, and numerical analysis was conducted to evaluate the aerodynamic performance. It was found that increasing the mass flow ratio of the upstream slot enhanced film cooling, decreased aerodynamic losses, and reduced the strength of passage vortex. However, reducing the distance between the slot and the blade leading edge only enhanced film cooling without affecting the leakage coverage area.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Rui Zhang, Zhen-lei Li, Yan-sheng Zhang, Dong Chen, Guo Yuan
Summary: This study discusses the heat transfer behavior of different jet forms on steel tubes. The results show that the annular jet performs better in terms of cooling intensity and uniformity. The cooling performances of the two jet forms are similar when the steel tube size is small. Therefore, the planar jet can be considered for smaller diameters due to its simplicity, low cost, and convenience in application.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
A. R. Khoei, A. M. Orvati Movaffagh, A. Rezaei Sameti
Summary: This paper presents a comprehensive study on the thermo-mechanical characteristics of oxide-coated aluminum nano-powder. It is found that the thermal conductivity of oxide-coated aluminum nano-powder is significantly lower than that of the bulk aluminum, and it is affected by the density and temperature.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Yanjin Wang, Jintao Xiong, Lingyu Chen, Zhihai Lv, Qian Wang
Summary: A solar radiation transfer model for spray cooling double skin facade (SC-DSF) is proposed in this study. The model is validated by experimental results and various influence factors are analyzed. The effectiveness of adjusting droplet coverage rate and size is also evaluated.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Bostjan Zajec, Blaz Mikuz, Anil Kumar Basavaraj, Marko Matkovic, Matej Tekavcic, Martin Draksler, Leon Cizelj, Bostjan Koncar
Summary: We have developed an advanced experimental setup to investigate flow and heat transfer in an annular channel. The setup allows heat transfer measurements and flow visualization using a temperature-controlled inner tube. Measurements can be conducted in both single-phase and two-phase flow regimes. The setup ensures a uniform velocity field in the annular channel using specially designed inlet and outlet headers. The inner copper tube is heated by water and contains turbulators for enhanced heat transfer and thermocouples for temperature measurement. A three-dimensional conjugate heat transfer CFD model has been developed and validated to accurately estimate heat losses in the setup. This study demonstrates the importance of numerical simulations in improving the interpretation of complex experimental results.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Weijie Chen, Ke Wang, Yongqing Wang, Shantung Tu, Zunchao Liu, Huijuan Su
Summary: In this study, a novel gradient porosity transpiration cooling plate structure (GP-TCPS) is proposed to alleviate heat transfer deterioration caused by non-uniform temperature distribution in transpiration cooling plate structure (TCPS). Computational fluid dynamics (CFD) and response surface method (RSM) were used for qualitative and quantitative analysis of the flow and heat transfer of GP-TCPS. The optimized structure of GP-TCPS significantly improves temperature uniformity, injection pressure, and average cooling efficiency compared to traditional TCPS.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
R. Essam, A. Elsaid, W. K. Zahra
Summary: This study presents a novel bioheat model for simulating heat transfer in skin tissue. The model offers an improved representation of thermal dynamics in the skin and has been validated using numerical solutions and experimental measurements. The study highlights the importance of incorporating vascular inlet parameters and thermal relaxation effects in the thermal profile, and suggests potential applications in thermal therapy and wound healing.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Dongbo Shi, Tao Xu, Zifeng Chen, Di Zhang, Yonghui Xie
Summary: The cooling structure design of turbine blades is crucial for the safety and reliability of the gas turbine set. This research investigates different arrangement schemes, including dimple/protrusion arrangements, to enhance the cooling performance. The results show that the arrangement scheme with both passes arranged by dimples has the best comprehensive thermal performance.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Emrehan Guersoy, Hayati Kadir Pazarlioglu, Mehmet Guerdal, Engin Gedik, Kamil Arslan
Summary: The thermo-hydraulic performance of Al2O3/H2O nanofluid with different nanoparticle shapes flowing in a sudden expansion tube with variable sudden expansion inclination angles and elliptical dimpled fins with different diameters were numerically investigated. The results showed that the nanoparticle shapes, sudden expansion inclination angles, and elliptical dimpled fin have significant impact on the thermo-hydraulic performance. This study reveals the novelty and importance of these factors in the research.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)
Article
Thermodynamics
Rukun Hu, Xinyu Huang, Xinyu Gao, Liu Lu, Xiaohu Yang, Bengt Sund
Summary: This study examines the impact of applying bottom cross-cut on PCM's spatial distribution in a horizontal LHTES unit using numerical simulation. The findings show that bottom cross-cut can improve the heat storage rate and natural convection heat transfer gain.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2024)