International Journal of Fire Science and Engineering最新文献

Comparative Study of Numerical Simulation and Experiment on Temperature Distribution and Central Vent Flow Velocity in Ceiling-vented Compartment Fire 顶棚通风隔间火灾中温度分布和中央通风口流速的数值模拟与实验对比研究

International Journal of Fire Science and Engineering Pub Date : 2023-09-30 DOI: 10.7731/kifse.9a45db07

M. Park, Yun Young Kim, Chi Young Lee

{"title":"Comparative Study of Numerical Simulation and Experiment on Temperature Distribution and Central Vent Flow Velocity in Ceiling-vented Compartment Fire","authors":"M. Park, Yun Young Kim, Chi Young Lee","doi":"10.7731/kifse.9a45db07","DOIUrl":"https://doi.org/10.7731/kifse.9a45db07","url":null,"abstract":"In this study, we conducted numerical simulations to analyze fire phenomena in a compartment with a ceiling vent and compared these numerical simulation results with previous experimental data. Based on the previous experimental conditions, under the heat release rate of 1.5 kW, the vent areas of 1% and 10% of the floor area and the fire sources both at the center and side of the floor were tested. Overall trends of temperature distribution and central vent flow velocity in the present numerical simulations were consistent with those in the previous experiments. The temperature within the compartment was observed to be higher when the vent area was smaller. For compartment with a smaller vent area, the temperature distribution showed minor variations with the fire source location. However, with a larger vent area, temperatures were notably higher when the fire source was at the side than at the center. The present numerical simulations slightly overestimated the temperatures from the previous experimental results, resulting in a bias factor of 1.07 and a model's relative standard deviation of 0.07 for temperature. Regarding the flow velocity at the center of ceiling vent, the fluctuations over time were more pronounced when the fire source was centrally located. When the fire source was at the center, the average central vent outflow velocity was higher for compartment with a larger vent area. When the fire source was positioned to the side, the vent area appeared to have minimal impact on the average central vent outflow velocity. It was also observed that the average central vent outflow velocity was higher when the fire source was centrally placed when compared to a side location. The present numerical simulations underestimated the previous experimental results for the average central vent outflow velocity, and the bias factor and the model’s relative standard deviation for the average central vent outflow velocity were 0.63 and 0.39, respectively.","PeriodicalId":225639,"journal":{"name":"International Journal of Fire Science and Engineering","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139331964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study on Smoke Ventilation Performance According to the Opening Rate in a Corridor-Type Apartment 走廊式公寓根据开窗率计算的排烟性能研究

International Journal of Fire Science and Engineering Pub Date : 2023-09-30 DOI: 10.7731/kifse.1a1dcf5b

Ji-Heon Kwark

引用次数: 0

Risk-informed Emergency Response Training for Backdraft in Nuclear Power Plants 核电厂逆流风险知情应急培训

International Journal of Fire Science and Engineering Pub Date : 2023-09-30 DOI: 10.7731/kifse.ecb878f8

Mihyun Kim, Wonkook Kim, Hongki Kim, Jungman Kim, Sunhong Yoon, Jangwon Choi, Heemoon Kim

{"title":"Risk-informed Emergency Response Training for Backdraft in Nuclear Power Plants","authors":"Mihyun Kim, Wonkook Kim, Hongki Kim, Jungman Kim, Sunhong Yoon, Jangwon Choi, Heemoon Kim","doi":"10.7731/kifse.ecb878f8","DOIUrl":"https://doi.org/10.7731/kifse.ecb878f8","url":null,"abstract":"Research has been conducted for developing fire evacuation and response training programs for nuclear power plant (NPP) application. Among numerous fire scenarios that may occur in an NPP environment, three different points of origin for a fire were selected for the program based on a risk-informed approach: switchgear room, main control room, and safety injection pump room. Fire outcomes were predicted for these scenarios via numerical modeling and the results were incorporated into the newly developed fire evacuation and response training program for the APR1400, Korea’s next-generation NPP model. The switchgear room fire scenario was found to have the most potential for backdraft to occur during manual fire response following automatic gaseous fire suppression system activation. The emergency response manual does discuss this possible backdraft occurrence; however, the guidance to avoid injuries is qualitative, such as to be cautious of backdrafts and wait a sufficient amount of time after opening a door before entering the. In this study, backdraft phenomenon that may occur from a switchgear room fire was numerically examined using the recent version of the Fire Dynamics Simulator to develop an appropriate timeline to be implemented in the fire evacuation and response training program. Based on the findings, the following guidance is provided: (1) backdraft can only occur when the fire originates in the space near the door; (2) wait at least 10 minutes after opening the door before entering the room; (3) watch for rapid smoke production, as this may be an antecedent phenomenon of backdraft; and (4) when smoke production increases rapidly, leave the room as soon as possible to avoid being caught within the deflagrating flames from a backdraft.","PeriodicalId":225639,"journal":{"name":"International Journal of Fire Science and Engineering","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139333303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tensile Characteristics of Rubber Material of Firefighting Supplies According to Test Piece Shape 根据试件形状确定消防用品橡胶材料的拉伸特性

International Journal of Fire Science and Engineering Pub Date : 2023-09-30 DOI: 10.7731/kifse.05f2a959

Jong-Sang Kim, Yong-Taek Han

{"title":"Tensile Characteristics of Rubber Material of Firefighting Supplies According to Test Piece Shape","authors":"Jong-Sang Kim, Yong-Taek Han","doi":"10.7731/kifse.05f2a959","DOIUrl":"https://doi.org/10.7731/kifse.05f2a959","url":null,"abstract":"Currently, rubber materials are widely utilized in firefighting supplies. They are utilized as rubber packing, such as air respirators, rubber bands, such as pipe windows, and rubber packing, such as fire extinguishers. EPDM initially utilized the rubber packing material, but because of aging and curing, it is difficult to maintain air tightness in the cracked gap; therefore, it has been replaced with NBR and utilized until now. In addition, among the material's physical properties, tensile properties are required, and the form usually adopted as a tensile test specimen is generally an aging form. However, rubber utilized in firefighting supplies employs rubber packing or rubber ring products. Currently, tensile tests are conducted by manufacturing a sample as a dumbbell from a separately manufactured sample without conducting a tensile test with a rubber ring-type specimen. Furthermore, questions often arise about the tensile properties of rubber rings. Therefore, this study tested the tensile properties with a ring-shaped specimen. In KS M ISO 37, it is generally known that an annular-type test piece is desirable for tensile strength measurement. An annular-type test piece has a lower value than an annular-type test piece, and an annular test piece with an elongation rate is almost the same value as an annular-type test piece. Therefore, the test was conducted to find the difference between the test piece as a dumbbell and the actual ring-shaped specimen. As a result of the tensile test, the tensile strength was found to be lower in the range of 11.8-15.5% in the ring-shaped test piece than in the age-shaped test piece, and the elongation rate was lower in the range of 4.1-40.1% than in the age-shaped test piece. This is thought to be because the stress of the stretched high-ring-shaped specimen is not equal to the cross-sectional area of the specimen. However, the tensile property value of the rubber material was satisfied with both types of test pieces with the reference value required for approval.","PeriodicalId":225639,"journal":{"name":"International Journal of Fire Science and Engineering","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139333617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spray Characteristics Analysis of Fire Sprinkler Spray with Image Processing 利用图像处理分析消防水喷淋管道的喷水特性

International Journal of Fire Science and Engineering Pub Date : 2023-09-30 DOI: 10.7731/kifse.3544e86a

Saemi Bang, Taehoon Kim

{"title":"Spray Characteristics Analysis of Fire Sprinkler Spray with Image Processing","authors":"Saemi Bang, Taehoon Kim","doi":"10.7731/kifse.3544e86a","DOIUrl":"https://doi.org/10.7731/kifse.3544e86a","url":null,"abstract":"Sprinkler systems are effective in suppressing fires during their initial stages. The ability of a sprinkler to suppress a fire is contingent on the density, size, and velocity of the droplets it emits. In this study, a high-speed camera was employed to measure the size and velocity of droplets generated by a sprinkler head with a K-factor of 80. To capture images of the sprinkler spray, two acrylic partitions were placed 3 cm apart, with the sprinkler head positioned in the center. A light source was positioned behind the spray, and images were recorded at a resolution of 1024 × 1024 pixels and a speed of 4000 fps. During the image processing phase, bounding circles were drawn using the mean of the major and minor axes of the droplets, and these circles were used to calculate the diameter, velocity, and momentum of the droplets. It was observed that smaller droplets were predominantly present closer to the sprinkler head, while larger droplets were more prevalent in regions farther away. The larger droplets exhibited higher velocities and momentum. As the vertical distance increased, droplet velocity and momentum also increased, primarily due to the influence of gravity.","PeriodicalId":225639,"journal":{"name":"International Journal of Fire Science and Engineering","volume":"219 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139333669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Flow Rate on Smoke Control System for Railway Tunnel Fire 流量对铁路隧道火灾烟气控制系统的影响

International Journal of Fire Science and Engineering Pub Date : 2023-06-30 DOI: 10.7731/kifse.ee7a83fc

Yejin Ha, Joonho Jeon

引用次数: 0

Smoke Particle-Source Prediction Model Based on Multiple Optical Wavelengths Using Deep Learning 基于多波长深度学习的烟雾粒子源预测模型

International Journal of Fire Science and Engineering Pub Date : 2023-06-30 DOI: 10.7731/kifse.0722bf36

Yusun Ahn, Kyuwon Han, HoeSung Yang, Soocheol Kim, Jin Hwa Ryu, Kangbok Lee

{"title":"Smoke Particle-Source Prediction Model Based on Multiple Optical Wavelengths Using Deep Learning","authors":"Yusun Ahn, Kyuwon Han, HoeSung Yang, Soocheol Kim, Jin Hwa Ryu, Kangbok Lee","doi":"10.7731/kifse.0722bf36","DOIUrl":"https://doi.org/10.7731/kifse.0722bf36","url":null,"abstract":"Recently, installing smoke detectors has become crucial owing to the risk of fatal human damage that may be caused by inhaling smoke during a fire. Smoke detectors have been reported as highly efficient in detecting smoke particles from fire; however, they may generate false alarms because of their limitation in distinguishing the fire smoke from the smoke generated by daily activities. Despite the frequent occurrence of these false alarms, research on predicting the types of sources through smoke particles remains insufficient. This study involved the development process of an intelligent smoke detector for false alarm reduction that aims to predict the occurrence and type of fire and the evaluation of its performance using the light-scattering characteristics for fire/non-fire sources. First, a previous experimental dataset of fire-related conditions was collected from three fire sources and three non-fire sources to train the model with the light-scattering characteristics of the smoke generated from each source. In addition, to reduce the computing power, data preprocessing was performed on the collected dataset using the median and RobustScaler. Finally, we evaluated the prediction performance of the three deep learning models using three networks: RNN, LSTM, and CNN-LSTM. As a result, we confirmed that the scattering intensity of smoke particles has unique characteristics for each source. When the data preprocessing and prediction models were applied, all three models achieved an accuracy of 0.90 or higher. However, some errors occurred that appeared at similar scattering intensities. The proposed method differs from existing methods in that it presents the possibility of predicting fire and non-fire sources and can be used as an alternative for improving false alarms in the future.","PeriodicalId":225639,"journal":{"name":"International Journal of Fire Science and Engineering","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129944143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of a Forest Fire Detection System Using a Drone-based Convolutional Neural Network Model 基于无人机卷积神经网络模型的森林火灾探测系统开发

International Journal of Fire Science and Engineering Pub Date : 2023-06-30 DOI: 10.7731/kifse.26686d3f

Jihee Lee, Keesin Jeong, Haiyoung Jung

引用次数: 0

Case Study Analysis of Database Construction for Smoke Control Simulation Experiments Using Scale Model 基于比例模型的烟气控制仿真实验数据库构建案例分析

International Journal of Fire Science and Engineering Pub Date : 2023-06-30 DOI: 10.7731/kifse.50cf89b1

Hajun Im, Wonchang Kim, Keesin Jeong, Taegyu Lee

引用次数: 0

Strength Reduction of Concrete Subjected to High Temperatures: Effects of Various Aggregates 高温下混凝土强度降低:不同集料的影响

International Journal of Fire Science and Engineering Pub Date : 2023-03-31 DOI: 10.7731/kifse.f5c2b512

Wonchang Kim, Keesin Jeong, Hyeonggil Choi, Taegyu Lee

引用次数: 0