| 摘要 |
A method of determining blade tip timing measurement uncertainty comprising measuring time of arrival of each of a set of blades (4) at each of a reference set of stationary probes (3). A reference blade tip parameter is derived from the measurements and the position of each of the probes. A reference condition number is calculated from the position of each of the probes and each targeted engine order, and then a mean calculated. Combinations of fewer probes are determined. For each combination, a condition number is calculated and then a mean condition number is calculated. The combination means are ordered relative to the reference mean and a predetermined number of combinations are selected. A blade tip parameter is derived for the selected combinations. Finally uncertainty of the blade tip parameter for each selected combination is calculated as a percentage of the reference blade tip parameter. |
