Other
Research Web-Applications
Java Applet
for Horizontal Flame Spread Over Solid Fuels in Developing Channel
Tan Cao and
Subrata (Sooby) Bhattacharjee |
| Description: |
 |
| This Applet
calculates the Flame Spread Rate for Horizontal Flame Spread over a Solid
Fuel in an Opposing Forced Gas Flow on Flate Plat using the Modified Extended
Simplified Theory (MEST) developed at San Diego State University as presented
below:
This model requires
as inputs: Ambient properties of gas (gas is mixture of Oxygen and Nitrogen),
properties of solid fuels, PMMA (Polymethylmethachrylate) or Cellulose,
and model configuration parameters.
The results of
calculations found in the blue fields are:
RexFP_amb, Reynolds
number x_FP at ambient temperature and pressure.
V_eqv, equivalent
gas velocity experienced by the flame.
V_f, flame spread
rate.
tau_cr, thickness
at which the fuel behavior changes from thin fuels case to thick fuels
case or vice versa.
T and eta, dimensionless
spread rate and thickness.
|
| User
Instructions: |
| Launch the Java
Applet by clicking here or the
schematic. |
| Click the "Initialize"
button to retrieve the default properties and modify them to match the
conditions of interest. |
| Click the "Calculate"
button when ready to solve for unknown values. |
|
|
| Examples: |
Example
#1:
How do you find the flame spread rate over a horizontal PMMA having half
thickness of 0.02 m, in an opposing forced gas flow having a velocity of
0.2m/s, an oxygen percentage of 100%, a pressure equal to 1 standard atmosphere,
at temperature of 298 degF? (All other properties have default values).
Note: Thick Fuel Formula is applied when tau
> tau_cr.
Launch the Java
Applet by clicking on the link above. |
| Modify
the percentage of Oxygen, y_O2 to indicate 100% and the gas velocity, V_g
to show 0.2m/s. |
| Click
the "Calculate" button. The flame spread rate, V_f is 3.2585mm/s. |
Example #2:
How do you find the flame spread rate for 0.8 mm thick cellulose in gas
having 70% Oxygen and at pressure of 202.64 kPa? (All other properties
have default values).
Note: Thin Fuel Formula is applied when tau <
tau_cr.
Launch the Java
Applet by clicking on the link above. |
| Select
Cellulose from the fuel menu. |
| Change
the half thickness, tau to 0.4 mm/s, the ambient pressure to 202.64 kPa,
and the percentage of Oxygen,y_O2 to 70%. |
| Click
the "Calculate" button. The flame spread rate, V_f, is 4.6397 mm/s.
. |
| Modified
Extended Simplified Theory, MEST, Formula for Spread Rate: |
 |
|
|
|
| Comparison
of the simplified model prediction with experimental results: |
| Related
Paper:"Determination
of Spread Rate for Downward Flame Spread over Thick Fuels" |