In order to complete experiments with dodecane, the surrogate fuel, and JP-8, it was necessary to implement a fuel vaporizer because the temperatures to achieve the required partial pressures of these fuels exceeded the capability of the bubbler system. The liquid fuel flow rate was controlled by a syringe pump (Chemyx inc. Fusion 100 fitted with a gastight #1001 syringe from Hamilton). Energy for vaporization was delivered by an electrically heated, fluidized bed (Techne SBS-4) . The nitrogen/C2H4 flowed into a stainless steel coil immersed in the fluidized bed. The liquid fuel was added to the stream in a T-fitting just before the fluidized bed. Heating tapes and a heated flexible line were used to maintain the temperature of the mixture above the dew point of the liquid fuel component. A heated flexible line (Atmoseal with temperature controller and maximum temperature of 250 ºC) was used to connect the outlet of the vaporizer to the entrance of the high pressure chamber. Heated tapes were used around the fuel lines inside the high pressure chamber. In order to install the heating tapes, the flexible fuel lines inside the chamber were converted to standard stainless steel lines which means that the burner cannot be translated vertically anymore. This only affects the ability to perform absorption scans, not the LII or LIF measurements. Heating tapes with a maximum temperature of 230 ºC were used in order to avoid hot spots that could lead to fuel decomposition. Thermocouples were placed between the fuel lines and the heating tapes to monitor the heating tape temperatures.
Published On January 2012 By Dr.. W. M Roquemore (Principal Investigator) Air Force Research Laboratory Prof. T. A. Litzinger (Co-Principal Investigator) Pennsylvania State University Read the full article here.