Accession Number : ADA596192


Title :   Measurement Techniques for Flow Diagnostic in ITAM Impulse Wind Tunnels


Descriptive Note : Conference paper


Corporate Author : RUSSIAN ACADEMY OF SCIENCES NOVOSIBIRSK INST OF THEORETICAL AND APPLIED MECHANICS


Personal Author(s) : Kharitonov, A M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a596192.pdf


Report Date : Apr 2010


Pagination or Media Count : 21


Abstract : Like blowdown wind tunnels, impulse facilities are used to measure the angles of attack, roll, and yaw, coefficients of the drag and lift forces, and aerodynamic moments acting on the wings and fins of the flying vehicle. Strength, vibration, and strain calculations of flying vehicles require measurements of distributed aerodynamic forces over the surface under different conditions of motion. This complicated and labor-consuming problem is very important in studying the structure and conditions of formation of the resultant forces and moments. Hypersonic flight is characterized by extremely high stagnation temperatures. Under these conditions, the surface of the flying vehicle is subjected to significant aerodynamic heating owing to compression and friction in the ambient medium. Therefore, measurements of temperature and heat-flux distributions on the model surface are necessary for calculating the strength and strains of the flying vehicle and its cooling systems. Requirements to sensors and equipment in impulse wind tunnels, as well as in long-duration wind tunnels, are determined by the nature of the phenomenon under study. For instance, measurements of turbulent velocity oscillations require fast-response equipment and sensors with a resolution of 10(exp -4)/10(exp -5) s. Aerodynamic forces and moments, pressures, and heat fluxes are measured by fast-response strain-gauge transducers and calorimetric sensors possessing high accuracy and sensitivity, and also fast-response equipment. Studies of the flow structure involving measurements of parameter fields and panoramic patterns stimulate extensive applications of optical methods for both qualitative and quantitative measurements. In these situations, almost instantaneous flow patterns have to be measured, which is extremely important for studying the fine structure of the flow.


Descriptors :   *MEASURING INSTRUMENTS , AERODYNAMIC CHARACTERISTICS , MEASUREMENT , RUSSIA , STRAIN GAGES , TEMPERATURE , WIND TUNNELS


Subject Categories : Aerodynamics
      Test Facilities, Equipment and Methods


Distribution Statement : APPROVED FOR PUBLIC RELEASE