| 摘要 |
Measurements of net thrust of an aeroengine on a thrust balance in a test cell must be corrected to gross thrust and it is also advantageous to detect changes in the airflows into and through the test cell of a magnitude sufficient to alter significantly the thrust correction factor. The invention can accomplish both these objectives by obtaining measures of the static pressures pi and pe in planes i and e respectively of the test cell using pressure probes 29 and 31, and utilizing the measures of pi and pe (a) in a function of the form D=f(pi, pe) where D is the thrust correction necessary to convert the net thrust reading on the thrust balance to gross thrust, and (b) to monitor variations of pi and pe with respect to the net thrust and detect such of these variations as are outside predetermined limits of variation, such detection indicating the occurence of changes in the characteristics of the airflows sufficient to alter significantly the value of D.
|
