THE MATHEMATICAL MODEL OF THE STATIC PRESSURE FLOWING RECIEVER
The article considers the matters of constructing mathematical models of the static pressure following receivers (SPFRS) designated for sensing static pressure on helicopters in a range of airspeeds to 250…350 km/h. SPFRS consist of contracting and diffusing parts. The mathematical model of SPFRS was developed in accordance with results of experimental researches for defining static pressure, dynamic pressure, speed, speed inaccuracy, altitude inaccuracy. The adequacy of the obtained mathematical models is checked through the comparison with the results of experimental researches. The models allow getting reliable data at the contractor convergence angle in 30-70 degree, the diffuser aperture angle in 8-14 degree, the diaphragm coefficient in 0.15-0.45, windblast speed in 20-250 km/h. The influence of separate components (a contractor and a diffuser) on SPFRS pressure coefficient and correlation between experimental data and the results obtained with the mathematical model are considered. With the use of the obtained mathematical models, the process of developing receivers with predicted metrological characteristics can be automated. The ability to take up receivers with required form factors for the specific control object on the original development cycle promptly has been appeared.