Haejun Park - Projects

Accessible means of egress for people with disabilities

While working at BRANZ in NZ, I had opportunities to attend several seminars where accessible means of egress were discussed with various stakeholders such as people with disabilities, carers, building facility managers, and fire service personnel. While agreeing with their ideas and thoughts about fundamental human rights, I naturally became to think about a huge potential cost and the number of people that can benefit from the accessible means of egress. This matter certainly requires philosophical and political decisions reflecting a social value system.

While this matter can be included in the building code which more likely specifies physical requirements of building, it may be also possible to handle it utilizing an emergency evacuation plan/strategy. The former approach is more about hard factors such as evacuation chair and hardened elevators and the latter one is more about soft factors such as a fire warden system and evacuation assistance training for people with disabilities.

No conclusion is made yet, but it may be totally different country by country.

Real-scale post-earthquake fire experiments at the University of California in San Diego

This was a very unique project as it had many project constraints;

- Fire tests were run in UCSD, remote from WPI, such that necessary tools and experimental apparatus for fire tests needed to be prepared in advance taking into account the lead time and the UCSD staff's availability.
- Fire tests were conducted after the earthquake tests were completed. The final damage state of the building which was closely related with the actual fire test scenarios were unknown until the last earthquake test.
- Due to the dry season in San Diego area and delays of earthquake tests, fire tests were conducted in an extremely tight time schedule.
  - 6 real scale fire tests were planned over three days at the 4 different locations in the third floor .
  - Only 4 and half days were available for probe instrumentation and operational check-up for the 6 fire tests.
  - Only 3~4 hours per day were available for fire tests since local firefighters were to be present during fire tests.

A 30 minute video clip made by UCSD TV is available in YouTube. A portion regarding fire tests starts from 17:54 s. This project was conducted under the guidance of Prof. Meacham.

Large scale nuclear trash bag fire experiments at WPI fire lab

A number of cone-calorimeter tests were first conducted to find out the minimum ignition heat flux and to understand ignition and fire phenomena of various materials commonly found in the trashbag near the glovebox facility of a nuclear powerplant. Then, real-scale trashbags (three different sizes) were ignited using a gas burner which is similiar to the one in the californica technical bulletin 133. HRRs and heat fluxes around the trashbags were measured in the standard ISO room environment using water-cooled total heat flux gauges, radiometers, thermocouples, and manufactured thin-skin calorimeters. This project was conducted under the guidance of Prof. Dembsey.

Further information and results of the project will be available in the following paper.

You, YG, Park, H., and Dembsey, N.A., "Burning Characteristics of wastebags in nuclear facilities", in progress.

WPI Fire lab ventilation optimization modeling using FDS

The department of fire protection engineering of WPI built a new fire lab which can accomodate fire experiments upto 3 MW in 2012. In preparation for the design of this fire lab, several different fires were modelled using FDS to identify the proper size and locations of the fume hood, the necessary capacity of the exhaust, and the effects of make-up air flow to the lab space. Especially, previous lab experience told that reducing the velocity of make-up air flow is critical for more consistent fire test results. The current fire lab has 8 mesh-type make-up air flow ventilation cylinders which can minimize the effects of air flows on future fire tests. This project was conducted under the guidance of Prof. Dembsey.

Fire incident research - Bouwkunde (Faculty of Architecture) in TU Delft

A fire started from a vending machine in the sixth floor of the Faculty of Architecture building in TU Delft, Netherlands resulted in the partial collapse after about 8 hour burning(Fortunately, no casualties). Using FDS, fire was modeled and the simulation results were used to identify critical factors of this tragic fire incident. Based on the available photo evidence, fire development was reconstructed along with the time, and the possible fire spread routes were identified. This project was conducted under the guidance of Prof. Meacham and Dembsey.

Further details of this project can be found in the following papers.

1. Meacham, B.J., Park, H., Engelhardt, M., Kodur, V., van Straalen, I., Maljaars, J., van Weeren, K., de Feijter, R. and Both, K., "Fire and Collapse, Faculty of Architecture Buidling, Delft University of Technology: Implications for Performance-Based Design", in Proceedings of 8th International conference on Performance-Based Codes and Fire Safety Design Methods, SFPE, Lund University, Lund, Sweden, June (2010).

Research on the performance-based design approach for KICT

This project was conducted on the request of Korean Institute of Construction Technology (KICT) in the context of a paradigm change from the prescriptive-based to performance-based fire safety approach. The objective of the project was two-fold:

1. to compile a list of properties of material used in construction and furnishing of buildings which are pertinent to performance-based fire engineering analysis.
2. to develop a set of criteria for assessing "good" versus "bad" performance-based fire safety design.

The project results are not available due to the non-disclosure agreement. This project was conducted under the guidance of Prof. Meacham and Dembsey.

Two-zone student model development

Based on the article: Quintiere, J.G., "Fundamentals of Enclosure Fire "Zone" Models", Journal of Fire Protection Engineering, 1:3 (1989) 99-119, a two-zone model is established using Matlab. To solve the stiffness due to the pressure term, an implicit numerical method using Jacobian matrix was used. Relevant document and matlab code are are available.

Pressure profile.avi

A simple CFD student model development

FDS seems like a magic box from which fire development and smoke movements are modeled with a few lines of input commands. This work aimed at developing a relatively simple model to understand how FDS works for students taking the fire modeling class at WPI. Only hydrodynamic model in FDS is targeted and modeled using a 2-dimensional geometry. Relevant document and Matlab codes (1 and 2) are available. This project was conducted under the guidance of Prof. Dembsey.

2D-FDS_Vel.avi

2D-FDS_Temp.avi

HRR and smoke yield calculations from the cone calorimeter

A simple study project was conducted to understand how cone-calorimeter calculates HRR and smoke yield. Relevant documentation is available here.

Spontaneous ignition phenomena using various dust particles

Spontaneous ignition phenomena using an electric hot surface was studied during my M.S. period. This project was conducted under the guidance of Prof. Zalosh, Rangwala, and Dembsey.

The results were published in the following papers:

1. Park, H., Rangwala, A.S., and Dembsey, N.A., "A Means to Estimate Thermal and Kinectic Parameters of Coal Dust Layer from Hot Surface Ignition Tests", Journal of Hazardous Materials, 168:1(2009) 145-155.
2. Park, H., Zalosh, R., "Airflow and Oxygen Concentration Effects in Dust layer Hot Surface Ignition Temperature Tests", in Proceedings of 5th International Seminar on Fire and Explosion Hazards, Univeristy of Edinburgh, UK, 23-27 April (2007)