• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.438-443
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• 2008

Fire model shall be verified and validated to reliably show the predictive capabilities for a specific use. In the process of model verification and validation, both the acceptable uses and limitation of fire model are established. In this study, the results of FDS simulation are compared with the data of PRISME experiment such as temperature, heat release rate, heat flux, product concentrations in the under-ventilated two-room condition. Furthermore, the sensitivity of FDS under ventilation condition changes are evaluated. FDS provide the reliable prediction for under-ventilated two-room fire scenario with slightly deviation.

• Journal of computational fluids engineering
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• v.16 no.4
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• pp.55-63
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• 2011

In this study, Fire Dynamic Simulator (FDS) has been improved with the implementation of marker particles. Convectional FDS is able to implement only two curved geometries, namely, circular cylinders and spheres. The introduction of marker particles made it possible to implement arbitrarily curved objects. Moreover, an algorithm that extracts the marker particle information from a model designed by AutoCAD was developed. With the present implementation, applicability of FDS is greatly enhanced, beneficial to both academia and industry.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.270-273
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• 2012

오픈 소스인 FDS(fire dynamic simulator)는 건물, 터널내의 화재나 연기, 열기류의 거동을 연구하기 위하여 국내외적으로 광범위하게 이용되고 있다. 체계적인 연구와 확장이 가능하도록 소스코드와 프로그램구조, 각종 메뉴얼을 갖추고 있으며 향후 개발 방향을 온라인을 통해서 소스코드와 함께 공개하고 있다. 비압축성 비정상해석을 근간으로 하고 있으며 난류유동을 해석할 수 있도록 DNS와 LES모델을 가지고 있다. 화재, 연소, 스프링클러, 화재 확산 등의 모델링을 제공하고 있다. 이러한 모델을 바탕으로 다양한 시나리오의 재난, 피난에 적용할 수 있다. 향후 이러한 기본 모델을 바탕으로 새로운 재난 시나리오에 따라 새로운 알고리즘의 적용하기 위해서는 FDS 기본적인 구조와 모델, 그리고 한계점을 이해할 필요가 있다. 본 연구에서는 이러한 FDS모델을 더욱 확장하기 위한 일환으로 FDS(V5.5.3)의 기본적인 구조을 파악하고 몇 가지 검증모델(verification)에 적용하였다. 또한 이를 향후 FDS의 소스코드를 확장할 수 있는 근간으로 삼고자 한다.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.25 no.2
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• pp.208-213
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• 2023

Flow-diverting stents (FDSs) have proven advantageous for the treatment of large, fusiform, and dissecting aneurysms that are otherwise difficult to treat. Retreatment strategies for recurrent large or giant aneurysms after FDSs are limited to overlapping implantation of an additional FDS or definitive occlusion of the parent vessel. We report a recurrent giant aneurysm that was initially treated with an FDS with coils and was successfully treated with an additional FDS. Visual symptoms due to the mass effect of the recurrent aneurysm were completely resolved, and follow-up digital subtraction angiography revealed complete obliteration of the aneurysm. Additional FDS implantation for the retreatment of incompletely occluded aneurysms after the initial FDS treatment may be feasible and safe. Further studies are required to validate these results.

• Fire Science and Engineering
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• v.23 no.5
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• pp.103-109
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• 2009

In this study, fire simulations on the under-ventilated compartment fires have been conducted using the Fire Dynamics Simulator (FDS Ver. 5.2) and its prediction performance on the thermal and combustion chemical characteristics has been discussed. The temperature and chemical species concentrations in the upper layer of methane, heptane, and toluene fires located in a 2/5 scale compartment based on the ISO-9705 standard room are predicted and compared with the previously published experimental data. The results showed that the FDS simulations reproduced well the temperature of the ceiling and the mixture fraction in the upper layer under the well-ventilation conditions. For the under-ventilated fires, which were taken place due to the insufficient oxygen entrainment, the prediction by the FDS significantly under-estimated the production of carbon monoxide and soot compared to the experimental data.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.220-223
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• 2012

Generally, SAW device, which uses Time Domain Sampling, requires high speed AD converter because SAW device (TDS) needs high sampling speed as much as its high data speed. However, the high price of AD converter discourages makers from using it. On the other hand, SAW device, which uses Frequency Domain Sampling, does not required high speed AD converter because SAW device (FDS) does not need high sampling speed. It is very efficient in price comparison to its performance because high processing speed of SAW device (FDS) can be implemented using low price Embedded Systems. The purpose of the thesis is to solve the issues above by designing and realizing SAW device (FDS) using SAW sensor for TDS.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.6
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• pp.663-673
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• 2011

In this study, we analysed the effect of the fire source in the warehouse under the bridge and the height of the bridge using FDS code. To compare accuracy of simulation results, we simulated the experimental result with unit combustibles which is heptane as well as the mock-up test. Using this method, we evaluated the fire safety of the bridge which contains spalling and strength damage of concrete as well as damage of reinforcements according to the fire source and the height of the bridge. Most of the bridges are vulnerable to spalling of concrete. The book combustion has the strongest fire intensity which is expected to damage the bridge less than 30m height in the three types of the fire sources. The bridge over the 30m height can ensure the fire safety in the case of the rubber combustion.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.312-315
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• 2012

Generally, SAW device, which uses Time Domain Sampling, requires high speed AD converter because SAW device (TDS) needs high sampling speed as much as its high data speed. However, the high price of AD converter discourages makers from using it. On the other hand, SAW device, which uses Frequency Domain Sampling, does not required high speed AD converter because SAW device (FDS) does not need high sampling speed. It is very efficient in price comparison to its performance because high processing speed of SAW device (FDS) can be implemented using low price Embedded Systems. The purpose of the thesis is to solve the issues above by designing and realizing SAW device (FDS) using SAW sensor for TDS.

• Fire Science and Engineering
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• v.33 no.4
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• pp.50-58
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• 2019

The prediction performance of B-RISK was evaluated for the fire behaviors of combustibles in a compartment using Fire Dynamics Simulator (FDS). First of all, to predict the heat release rate (HRR) for two combustible sets, the HRR for one combustible set and the design fire curve were used as input values for B-RISK. Comparing results of B-RISK calculations with experimental data for two combustible sets, it was found that B-RISK results predicted insufficiently for fire growth rate of experimental data but there was good agreement for maximum HRR and total HRR with the experimental data. And the B-RISK results were used for input values of FDS to evaluate the fire behaviors of B-RISK results. Comparing results of FDS calculations with experimental data, the simulation results showed that the temperature and concentrations of O₂, CO₂ in the fire growth phase were different from the experimental data. However, when using the B-RISK result for percentile 70%, the simulation results sufficiently predicted the overall fire behaviors.

• Fire Science and Engineering
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• v.28 no.5
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• pp.23-29
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• 2014

The present study has been conducted to investigate the validity of the computational fire model and the results predicted by BRANZFIRE zone model and FDS field model are compared with a real scale fire test with spray fire in a multi-compartment. The liquid spray fires fueled with toluene and methanol are used as the fire source and the quantitative measurement of heat release rate is performed in an isolated ISO-9705 compartment with a standard door opening. The temperature field predicted by FDS model showed good agreement with the measurement in the fire room and the corridor, and BRANZFIRE model also gave acceptable result in spite of its simplicity and roughness. The mean temperature predicted by FDS model corresponds with measurement within maximum discrepancy range of 25% and the overall mean value of FDS model matched well with experimental data less than 10%. This study can contribute to establish the limitation and application scope of computational fire model and provide reference data for applying to reliable fire risk assessment.