We propose to design, test, and deliver a system that can be used to calibrate absorption-based soot monitors which are used to determine fuel emission indices for aircraft engines. The centerpiece of this system will be a modified version of the CAPS PMSSA monitor which provides a means of determining a sample absorption based on a true particle standard. It will be coupled to a means of producing absorbing particles whose physical and optical properties have been accurately measured and characterized.
Vehicles for subsonic and supersonic flight regimes will be required to operate on a variety of certified aircraft fuels and emit extremely low amounts of particulate emissions to satisfy increasingly stringent emissions regulations. An in situ calibration technique for absorption-based soot mass measurement monitors, of which there are currently none, would be quite desirable as factory calibration is extremely time consuming and expensive.
There are hundreds of absorption-based monitors used for measurement of aircraft and diesel engine soot emissions and ambient absorption. All of them require expensive factory calibration. There is also no means of checking whether the monitors are working properly on-site. The market for a monitor which would confirm proper calibration of the monitor in situ would be a much sought-after product.