Fire/Arson Investigations : Fire/Arson Investigations
A place to ask questions and add to probative and informative discussions associated with the various aspects of the field of fire investigation. -- FORUM RULES---BE CIVIL AND NO NAME CALLING, NO BELITTLING, NO BERATING, NO DENIGRATING others. Postings in violation of these rules can be removed or editted to remove the offending remarks at the discretion of the moderators and/or site administrator.
Re: High Temperature Accelerants (HTA)
Posted by: dcarpenter (IP Logged)
Date: May 19, 2010 04:28PM
The burning of hydrocarbon liquids usually involves the oxygen in air as the oxidizer. Air also contain significant nitrogen that acts as a "thermal ballast" that moderates the temperature and that is why the temperatures for different burning hydrocarbons in air are about the same. That is, gasoline has an adiabatic flame temperature about the same as other common hydrocarbon fuels when air is the oxidizing agent.
HTA may include fuels that are self-oxidizing. There was previous mention of road flares and pool chemicals. Road flares are like a solid rocket fuel where the fuel and oxidizer are mixed to create a self-oxidizing fuel. Pool chemicals can also be mixed with fuels to create a self-oxidizing fuel. These types of fuels do not require air as the oxidizer and thus, the nitrogen does not play a role in moderating the temperature.
It is important to understand that an increase in the burning rate of a hydrocarbon liquid burning in air will increase the heat release rate (i.e. the size of the fire), but it does not change the flame temperature.
Douglas J. Carpenter, MScFPE, CFEI, PE, FSFPE
Vice President & Principal Engineer
Combustion Science & Engineering, Inc.
8940 Old Annapolis Road, Suite L
Columbia, MD 21045
(410) 884-3266
(410) 884-3267 (fax)
www.csefire.com
HTA may include fuels that are self-oxidizing. There was previous mention of road flares and pool chemicals. Road flares are like a solid rocket fuel where the fuel and oxidizer are mixed to create a self-oxidizing fuel. Pool chemicals can also be mixed with fuels to create a self-oxidizing fuel. These types of fuels do not require air as the oxidizer and thus, the nitrogen does not play a role in moderating the temperature.
It is important to understand that an increase in the burning rate of a hydrocarbon liquid burning in air will increase the heat release rate (i.e. the size of the fire), but it does not change the flame temperature.
Douglas J. Carpenter, MScFPE, CFEI, PE, FSFPE
Vice President & Principal Engineer
Combustion Science & Engineering, Inc.
8940 Old Annapolis Road, Suite L
Columbia, MD 21045
(410) 884-3266
(410) 884-3267 (fax)
www.csefire.com
Sorry, only registered users may post in this forum.