Method and System to Determine Heat Release Rate and Total Heat Release of Aircraft Cabin Materials using Auto-Calibration

A system for determining the heat release rate of a sample material, the system comprising a computing device coupled to a heat release rate apparatus, the heat release rate apparatus comprising:

• an environmental chamber having a tubular structure with openings at a top end and a bottom end thereof, the environmental chamber comprising a plurality of heating elements that provide heat flux directed at the sample material, and an upper pilot burner and a lower pilot burner, wherein the lower pilot burner initiates combustion of the sample material and the upper burner ignites off-gassing products during testing of the sample material,
• the environmental chamber comprising first and second stage distribution plates each having a plurality of holes therein to provide laminar flow within at least a portion of the environmental chamber;
• a holding chamber having a tubular structure with openings laterally at a distal end and a proximal end thereof, the holding chamber tangentially coupled to the environmental chamber with a radiation door assembly between the environmental chamber and the holding chamber;
• a single plenum pyramidal section having openings at a top end and a bottom end thereof, the bottom end of the pyramidal section coupled to the top end of the environmental chamber;
• and
• a plurality of sensors comprising a set of first temperature sensors located at the outlet opening of the pyramidal section for measuring exit gas temperature and a second temperature sensor for measuring inlet air temperature,
• wherein the set of first temperature sensors comprise a plurality of thermocouples configured to continuously monitor exit gas temperature, and
• wherein the plurality of thermocouples comprise at least five thermocouples with ends located below the outlet opening of the pyramidal section, including a first thermocouple with an end placed at a geometric center of the outlet opening, and four other thermocouples with ends placed at the outlet opening radially from the first thermocouple end and along a single horizontal plane within the outlet of the pyramidal section;
• wherein the computing device is configured to receive temperature readings from the plurality of sensors, including the exit gas temperature and the inlet air temperature, and to determine the heat release rate (HRR) of the sample material based on absolute temperature differential of a combustion stream through the apparatus, determined based on an average of inputs from the first and the four other thermocouples at the outlet temperature determined, and inputs from the second temperature sensor.