Autoignition systems to measure autignition temperatures and related methods

A method to measure autoignition temperatures, the method comprising:

• flowing a gas from at least one gas source into a vessel chamber of a pressure vessel via at least one gas inlet to at least one of increase an absolute pressure of the vessel chamber to 101 kPa or maintain the absolute pressure of the vessel chamber at 101 kPa, the pressure vessel including one or more vessel walls defining the vessel chamber and an opening, the pressure vessel including a lid covering the opening and secured to the one or more vessel walls, wherein the absolute pressure of the vessel chamber is detected using at least one pressure sensor;
• increasing a temperature in a furnace chamber of a furnace, the furnace disposed in the vessel chamber, the furnace including one or more furnace walls defining the furnace chamber;
• and
• disposing at least one sample into the furnace chamber through at least one sample inlet defined by the furnace.

An autoignition system to measure autoignition temperatures, the autoignition system comprising:

• a pressure vessel including one or more vessel walls defining a vessel chamber and opening, the pressure vessel including a lid configured to cover the opening and be secured to the one or more vessel walls, the one or more vessel walls including at least one vessel transparent section, the pressure vessel defining at least one gas inlet and at least one gas outlet;
• a furnace disposed in the chamber, the furnace including one or more furnace walls defining a furnace chamber, the furnace defining at least one sample inlet configured to allow a sample to be disposed in the furnace chamber, the furnace configured to controllably heat the furnace chamber;
• a sample dispenser disposed in the vessel chamber and outside of the furnace chamber, the sample dispenser configured to dispense at least one sample into the furnace chamber through the at least one sample inlet;
• at least one gas source in fluid communication with the gas inlet of the pressure vessel;
• at least one pressure sensor configured to detect a pressure within the vessel chamber;
• a controller configured to control at least one of a rate at which a gas is provided from the gas source to the vessel chamber or a temperature in the furnace chamber;
• and
• at least one safety outlet defining a passageway and a film disposed in or covering the passageway, the film configured to fail when a pressure differential between the vessel chamber and an exterior of the pressure vessel is about 100 kPa to about 500 kPa.