Plant Disaster Preventing Simulation

FPEC had developed as a company specialized in fire protection system engineering, disaster prevention and risk analysis of in process plants. With the advantage of deep knowledge and abundant experience in this field, FPEC have developed PC software for simulation of fire, explosion, gas dispersion, boil over etc., and  by use of these software, FPEC is now doing the contracted business of assessment of severity of the disaster and its countermeasures, such as disaster prevention plan.

FPEC also provide numerical simulation of fire, explosion, gas and smoke dispersion using FDS developed by NIST and other CFD solvers .
Click here for more information on the numerical simulation.

Please note that we do not sell our own programs, and it is our business policy to provide calculation results by our programs as a contract business. We will report the results by utilizing various simulations according to customer's requests.

 

Disaster Preventing Simulation for sequential disasters 

In carrying out disaster preventing simulations, it should be noted that, for example, explosion will not occur with no reason, and before explosion, there may be leakage, gas dispersion, or fire in same cases, and then VCE or BLEVE may occur.  That means there may be sequential accidents or disasters before the last disaster.
FPEC will do the assessment by various simulation for the sequential disasters as described below.  Please note again, disaster will not occur alone, but multiple accidents or disasters will occur sequentially.

 

Disaster Scenario
Leak from Sphere Tank Crude Oil Tank Full Surface Fire Leak from Pressure Vessel
storing Toxic Gas
------------------------------------------------- --------------------------------------------------------  -----------------------------------------------
To initiate leakage.
(calculate the volume of leakage and evaporation gas)
To initiate full surface fire.
(calculate heat flux level from fire to make heat flux map)
To initiate leakage.
(calculate the volume of leakage and evaporation gas)
Gas Dispersion
(calculate the area over 50% of LEL, where flash fire is possible, to make 3D concentration map)
Fail to extinguish the fire and boil-over occurs.
(calculate the time of boil-over, hot zone temperature and oil volume remained in the tank)
Gas Dispersion
(calculate the concentration of gas in ppm, LEL, or odor level by each time step to make its map)
 
Ignite the gas cloud and flash fire occurs.
(show the space enveloped by the flash fire on 3D map)
Calculate the heat flux level from the burning froth at boil-over and max. distance of fired oil flying ,to show on the map  
   
Flash fire back to the dike .
(calculate heat flux level from the dike fire to make heat flux map)
   
   
The sphere exposed to the fire and BLEVE  occurs.
(calculate the range of pressure wave and max. distance of debris flying, to show on the map)
   
   
Fireball occurs.
 
(calculate the heat flux from the fireball and to show on the map)
   

  


Major software developed by FPEC 

Major software for plant disaster preventing simulations developed by FPEC is as below.

Free FM-VIEWER for “Heat Radiation Simulation,” “Tank Fire Extinguishing Simulation” and “Water/Foam Monitor Mapping Software (Trajectory simulation)” is available so that you can experience what firefighting simulation results against plant fires look like more closely.
Click here to see more information on FM-VIEWER.

 

  1. Leakage, liquid spreading, and evaporation simulation

    This program calculates the leak rate, flash rate, spreading speed of leaked liquid over the ground, and evaporation rate from the liquid pool along the elapsed time after start of the leakage.  The atmospheric temperature, wind speed, solar heat intensity, and presence or absence of dike are also reflected in the calculation.

  2. Gas dispersion simulation

    As the calculation model, puff model, which is generally used as atmospheric dispersion assessment, is used. The intervals between puffs is as close as possible, and the calculation accuracy is increased by adding the concentration from each puff.  The program also supports change in weather conditions, exhaust gas volume and its concentration.

  3. Explosion simulation (BLEVE・Fire-Ball・VCE)

     Our software is based on the disaster prevention guidelines of the petrochemical complex in Japan (hereinafter referred to as “Combi-Guidelines”) and Guidelines for Vapor cloud explosion, pressure vessel burst, BLEVE, and flash fire hazard by American Institute of Chemical Engineers (AIChE).  The software calculates pressure wave from BLEVE, or VCE possibly occurring in chemical plants, etc., and diameter, height of the center and heat radiation from fireball generated following BLEVE.  In addition, the possibility of flash fire and the extent of damage are studied by together with gas dispersion simulation. 

  4. Heat radiation simulation (tank fire / leakage fire)

    The software makes a map of the radiation intensity from the tank fire, dike fire, and other oil leak fires (pool fires).  The oil spill pool can be set at any location of the process area, etc.  The radiation intensity is calculated with the various factors, such as the wind speed, humidity, atmospheric temperature, and physical properties of the flammable liquid, etc.  The radiation intensity at any heat receiving surface at the upwind or downwind, at any vertical height, at horizontal, vertical or maximum heat receiving angle can be calculated.  The 3D radiation intensity map that covers changes in the height of the heat receiving surface can also be made.  The calculation method is basically based on Mudan's method described in NFPA, but calculation by the "Combi-Guidelines" or the method adopted by NIST can also be possible.

    Click here to download FM-VIEWER.

  5. Boil-over simulation

    It is well known that the biggest disaster is boil-over, when the large crude oil tank is on fire.  We have developed a simulation program for boil-over of the tank full surface fire, which can calculate the temperature and growth rate of the hot zone, and also can calculate the oil temperature change in the tank after extinguishing the fire.  The occurrence of boil-over depends on the distillation characteristics of the oil, and  it is now possible to predict the possibility and initiation time of boil-over depending on the oil distillation curve. In addition, the time required to cool the hot oil remained in the tank after the fire is extinguished can be predicted.

  6. Crude oil evaporation and dispersion simulation

    When crude oil leaks to the dike, firstly a light fraction evaporates and spreads, and it takes a very long time to evaporate most of light gas components and become an evaporation residue such as asphalt.  We have developed a program that calculates evaporation rate and volume of the residue along the time passing, depending on the distillation characteristics of crude oil.  With use of some crude oil data whose component composition data are publicly available, this program calculates evaporated gas composition at the time and calculates the lower explosion limit (LEL) concentration according to Le Chatelier's law. 
    By the combination of those function and gas dispersion calculation, not only gas concentration map but also map of % of  LEL  can be made for at every moment.

  7. Tank fire extinguishing simulation

    This program was developed to simulate the fire extinguishing method for the full surface fire of floating roof tank by a large-capacity foam monitors. This program calculates the fire extinguishing time which is sum of the time required to establish the foam bridge head on the burning liquid surface and the time required for foam spreading to whole burning surface. Furthermore, this program has a function to determine the appropriate location of the foam monitor under any wind condition and a function to map the safe range of firefighting activities by heat radiation calculation.  It can be applied not only to floating roof tank fires but also to fire extinguishing simulations of fixed tank full surface fires using fire trucks and foam monitors.

    Click here to download FM-VIEWER.

  8. Water/foam monitor mapping software (Trajectory simulation)

    There is a program that simulates the trajectory of water from the water nozzle and that simulates the trajectory of foam from the foam nozzle.  Especially in the case of water discharge, it is possible to simulate not only solid water stream trajectory but also the trajectory the stream at any spray angle.  By using these trajectory simulation software, it is possible to examine appropriate mapping of fire trucks, ladder fire truck, water monitors, foam monitors, etc. in the event of a fire under wind condition.

    Click here to download FM-VIEWER.

  9. Fire-fighting equipment mapping simulation

    Although the arrangement of foam / water discharging equipment such as fire engines and water monitors can be examined by using a trajectory simulation and heat radiation simulation program, supplemental mapping software has been also developed to check whether it is possible to deploy fire hoses or to pass the fire trucks in the event of a fire. With use of these programs, it is possible to examine the appropriate location of firefighting equipment in case of various fire scenes.

    Patented
    Title of invention: Fire / extinguishing situation simulation system for fuel tank
    Patent number: 4382698