Abstract: Apparatus and methods are disclosed for determining internal engine characteristics using acoustic-vibration data. Exemplary such data are passive acoustic pyrometer data. Acoustic-vibrational frequencies emanating from a running engine are detected and compared to frequencies having known relationships to particular operating characteristics of the engine. In an example, the dominant frequency or other prominent frequency emanating from an internal-combustion chamber of a turbine engine is detected and used to determine the fuel-to-air ratio in the chamber. The determined data are used for performing adjustments or optimizations of engine performance, such as adjusting the fuel-to-air ratio as required or desired. In a similar manner, operating characteristics of other engines or engine-like environments, including furnaces and boilers, can be determined.

Abstract: Methods and apparatus for measuring the dielectric relaxation properties of a sample are disclosed. Methods are disclosed for amplifying or controlling the dielectric relaxation properties of a sample by adding particles, such as functionally coated particles. In certain methods, the particles amplify or control the dielectric relaxation properties of the sample by interacting with counter ions in the sample. In some embodiments, the methods use a dielectric relaxation spectroscopy apparatus with remote electrodes.