摘要 |
A gas flow sensor system, and method for gas flow rate measurement and self-calibration to overcome problems caused by degradation. Gas flow rate is accurately measured by determining the power dissipated at a constant differential temperature of a gas flow sensor, under conditions where its power dissipation is independent of its resistance. The gas flow sensor is adjusted to a predefined differential temperature compared to the temperature of the gas. In addition, variations in heat transfer coefficient (h) of a gas flow sensor are corrected by self-calibration of the gas flow sensor system. Experimentally established correction factors are applied to the gas flow sensor, to compensate for changes in its heat transfer coefficient (h) caused by degradation of the gas flow sensor. This offsets the adverse effects of use and aging of the gas flow sensor, thus reducing errors in gas flow measurement. |