Jet fuel thermal oxidation test equipment

Abstract

Jet fuels' thermal oxidation characteristics are evaluated via the Standard Test Method for Thermal Stability of Aviation Turbine Fuels. This test method mimics the thermal stress conditions encountered by jet fuel in operation and is often carried out by laboratory devices, known as rigs. The rigs include a test section having a sleeve and a heater tube arranged therein. A pair of bus bars secure the test section to the rig and apply a current to the heater tube. The applied current heats the heater tube and subjects the sample jet fuels that are flowing in the volume between the sleeve and heater tube to high temperatures, which may produce thermal oxidation deposits on the heater tube. Heater tubes are difficult to install, however, and a gauge may be used to ensure accurate placement of the heater tube within the sleeve. In addition, the fuel sample must be prepared via an aeration process, and systems are disclosed for automating the aeration process such that the sample is prepared precisely according to the test standard. Moreover, the rig includes a pump system that moves the fuel sample through the test section, and a pump system is provided in a double syringe arrangement that optimizes fuel flow through the test section without fluctuation. Finally, the rigs include cooling systems for cooling the bus bars and maintaining an appropriate thermal profile within the heater tube, and cooling systems may be provided that independently control the temperature of each bus bar.