Accession Number : AD0762329

Title :   Aspiration of Aerosol Samples from a Flow by Using Zero Intake Tubes (Ob Aspiratsii prob Aerozolya iz Potoka Nulevymi Zabornymi Trubkami),

Corporate Author : ARMY FOREIGN SCIENCE AND TECHNOLOGY CENTER CHARLOTTESVILLE VA

Personal Author(s) : Belyaev,S. P.

Report Date : 20 MAY 1972

Pagination or Media Count : 13

Abstract : In working with particulate aerosols it is almost always necessary to know the weight concentration of impurity. The accepted method of measuring the weight concentration is to withdraw a portion of the flow by using an intake tube. It is known, however, that as aspiration proceeds, changes of concentration and range of particle sizes arise in the intake tube, in comparison with the concentration and range in the main flow. Results of a study of a zero type intake tube are given. It is shown what kind of conditions make the coefficient of isokineticity varies only slightly when the inflow rate changes. The need for introducing a new correction coefficient allowing for the shape of the tube is explained. A technique is suggested for calibrating zero intake tubes which provides maintenance of isokineticity during withdrawal of the samples. Formulae are recommended for choosing the basic structural dimensions of an intake tube of this type.

Descriptors :   (*AEROSOLS, SAMPLING), (*PARTICLES, AEROSOLS), GAS FLOW, NUMERICAL ANALYSIS, VELOCITY, PARTICLE SIZE, USSR

Subject Categories : Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE