Chia Chun Yu

Study on Numerical Simulation of a Fire on Heavy Oil Tank

Oil is important energy nowadays. Most oil products, such as gasoline, coal oil and diesel oil, are important fuel too. Tanks serve as storage to preserve various petroleum products. These dangerous inflammable articles require not only as much safety protection as possible but also safety intervals between tanks. Once a fire occurs to a tank, its combustion expands very fast and violently. Without sufficient intervals, chain reaction is very possible to happen and cause a disaster out of control. Fire of oil tank is not common, thus experience of extinguishing such fire is also extremely lacking. Therefore, it is important to research on tank fire and report quantified data. This study adopted numerical analysis method to simulate a fire in a tank area by applying Fire Dynamics Simulator (FDS), and investigate the effect of various related parameter on tank fire. The anticipation of this study is to provide fire protection information of various types of tanks in order to reduce the impact of such fire on environment and resource.

Numerical Simulation of the Performance-Based of the Building Fire Protection Safety Evaluation

In order to understand the fire safety of the various types of buildings, we need more flexible and efficient performance-estimating methods to verify fire protection safety in various types of buildings. Assuming can utilize computer fire simulation software CFAST / FDS + Evac to analyze Taiwans domestic fire cases, in order to understand in the different fires heat flow transfer, and toxic smoke diffuse, and human evacuation to escape, and other important fire parameter characteristics, in the building the fire protection safety evaluating to produce the efficiency. This study is used cases of fires in four-story old-style residential and commercial mixed-use buildings to explain building fire performance-based numerical evaluation methods, and to provide quantitative data and reference information in Taiwan performance-based codes creating and the fire protection to project design is helpful in the buildings.

Firefighting Tactics during a Fire Event at a Textile Factory

Many factories contain chemical substances, raw materials, and finished and semi-finished products; thus, a factory fire can cause substantial property losses and endanger lives. The Fire Dynamics Simulator (FDS) developed by the National Institute of Standards and Technology was used in this study to simulate a fire event at a textile factory in Taiwan. The circumstances of a 2010 fire event in Zhubei City were recreated using data from the fire department and print media, exploring changes in temperature, smoke, and the concentrations of harmful gases (i.e., carbon monoxide; CO). Criteria were established for judging the firefighting techniques used during the fire event. In other words, simulated results of the FDS were used to analyze and assess the planning and use of firefighting tactics to enhance the efficiency of firefighting and rescue techniques, decrease casualties and property losses, and increase the reference value of this study in its application to fighting future factory fires.

Numerical Simulation of Vehicle Crashes

Based on the European New Car Assessment Program, which offers rigorous testing conditions, this study developed a numerical model for the computer simulation of crash analysis and analyzed two crash situations: a high-speed vehicle crashing into a wall and a high-speed test vehicle crashing into a static vehicle. The Simulation model was constructed using the superior functions of the Patran software, and the Pam-crash software was employed to perform various calculations for analysis. In crashes, the structure of vehicle bodies are greatly compressed and deformed because of high-speed impact force, which simultaneously generates high speed acceleration. Vehicle structural deformation constricts the driver and passengers, and acceleration can cause them physical harm. Thus, the objective of this study was to identify the sources of harm to driver and passengers when crashes occur. The research results can be a reference for vehicle manufacturers in future vehicle development and a reference for future academic research.

Simulation and Analysis on Mechanical Strength of Reinforced Concrete Beam Undergoing a Fire

Reinforced concrete is a common structure in buildings in Taiwan. Steel bars, concrete materials and the structural strength of the reinforced concrete deteriorate due to high temperature deriving from a fire. Therefore, it is essential to assess its structural safety and analyze whether the architectural structure will remain its design strength undergoing a fire. This study employs Fire Dynamics Simulation (FDS), fire simulation software, to construct model of thermal flow field. By integrating FDS with PHOENICS, thermal flow software, this study also calculates the effect of the fire’s thermal transmission on the building, investigates the effect of the fire size and the mode the beam undergoing a fire on change of the structural strength, and provides quantified data for safety assessment for buildings which have undergone fires.

Safety Verification of Mechanical Properties of Reinforced Concrete Beam in the Fire by Applying CFD

Advanced countries have adopted performance-based protective design to evaluate safety of buildings for building’s function of fire protection. And they have employed technology of fire protection engineering and quantified data of theoretical numerical model to create an even more flexible evaluation method for building’s fire protection. Buildings suffered varied degree of attack from elevated temperature and thermal radiation, which leads to changes in physical, chemical and mechanical properties, might result in considerable damage to the buildings and their structure. Such damage threatens populace life. This paper uses FDS (Fire Dynamics Simulator) software to analyze thermal flow field of fire. The temperature boundary condition of simulation results are then entered in the CFD (Computer Fluid Dynamics) software PHOENICS to calculate internal temperature and mechanical property of the beam. This study also integrates related experimental literatures as auxiliary to calculate thermal transmission and strength. Purpose of the above is to investigate elevated temperature and reduction of mechanical property, as well as verify safety of structure.

Computer Simulation and Analysis on Fire Verification and Smoke Distribution of the Entertainment Areas

Along with the economic growth, more crowded entertainment places are growing dramatically and the safety concerns are no longer contained as usual. The huge property damage and heavy casualties of fire caused by the owner ignorance of safety management or the fall short of the fire resistance specifications. These factors caused serious casualties after fire occurred. This research utilizes Fire Dynamics Simulator (FDS) software to analyze and simulate the fire accident that occurred in a public entertainment places on Po-Li bar, KeeLung City, Taiwan. The computer simulation calculates the fire spread and smoke distribution at the fire scene, and is in reasonable agreement with the post report provided by the fire department and photos. Simulation results of the various important parameters - such as temperature, CO concentration and smoke layer height during the fire time domain are obtained. This study will provide the improvement of fire parameters and suggestions to avoid future unfortunate events.

Smoke Transport Calculation during a Wooden Residential Structure Fire

This is a case study of cottage housing in Taiwanese military dependents’ villages that are primarily wooden structures with brick walls. When a fire ignited in one of these structures, sufficient air on the exterior of the building promoted the rapid ignition of the wooden structure. Because residents were a woman and child who lacked fire safety and escape knowledge, the fire resulted in two deaths. When fires ignite in wooden structures, toxic particulates in the smoke generated from the burning and decomposition spread rapidly because of thermal buoyancy effect, causing difficulties for escape and rescue. This research utilizes the fire dynamics simulator (FDS) software to simulate the fire scenario to discuss the impacts of smoke diffusion at a fire site and analyze the main causes of the fire. We also provide suggestions in the hope of offering information on fire safety precautions for this structure type to prevent future similar disasters.

Ultimate Strength Analysis for a Concrete Beam after a Sustained Building Fire

More than 90% of the buildings in Taiwan use reinforced concrete (RC) structures. It is crucial to human life and property to determine whether the RC structure is safe after fire damage. However, it is impossible to obtain fire thermal parameters quantitative data from actual building fires. Therefore, numerical simulation software that simulates fire scenarios was used to model fires for fire protection engineering. Beam strength decreases because of high temperature. To obtain precise beam temperature profiles in a building fire, this study used the fire model FDS and field model PHOENICS software to simulate fire development and beam inner temperature variation. Fire scenarios and beam surface temperatures in a room fire were analyzed by the FDS fire model. Beam boundary temperatures were transferred into the PHOENICS field model to compute the detailed temperature profile within the beam. The structural strength was estimated by using beam various cross-section temperatures to investigate dynamic ultimate bending moment of a RC beam in a room fire. Through the various simulations and calculations, this investigation obtained the influence of various beam positions, fire intensity, fire duration and fire damage sustained (whether two or three faces) by a RC beam after a building fire.

CFD Application for Performance Based Safety Verification of Reinforced Concrete Beam in Computer Simulation Building Fire

More than 90% of the buildings in Taiwan use reinforced concrete (RC) structures. Before or after fire damage, whether the RC structure accord Performance Based Design (PBD) fire code or safe evaluation are important in building fire protection verification. However, obtaining fire thermal parameters detailed quantitative data from building fire tests or actual building fires are difficult. Therefore, computational fluid dynamic (CFD) integration to simulate fire scenarios has been widely utilized in fire protection engineering. This study utilizes Fire Dynamics Simulator (FDS) fire model and PHOENICS field model software to simulate fire development and beams inner temperature variation. The structural strength estimated using beam cross-sections temperature to investigate dynamic ultimate bending moment (Mu) of RC beams. This integration method can investigate the influence of different beam positions, fire intensity, fire duration and fire damage sustained (two or three faces heated) for RC beams fire protection safe verification.