FIELD: radiation safety of atomic power stations. SUBSTANCE: invention can find use in measurement of meteorological parameters in mix of automated system monitoring radiation situation, in experimental gas dynamics and electrodynamics of continuous media. Method is based on recording of flight time of ion cloud through cylindrical conduit on which internal surface charge of like polarity is applied. This charge forms electric field different of zero surface region alone and prevents ions from cloud to hit internal surface of conduit. Optimum length of conduit is found by solution of problem of transfer of ion cloud through conduit carried out in diffusion-drift approximation with due account of change of profiles of longitudinal W(r,z) and lateral V(r,z) velocities of air flow which transfers ion cloud over length of conduit. Dependencies W(r,z) and V(r,z) are found by solution of system of Raynolds equations within bounds of (k-ε) model. EFFECT: increased sensitivity and decreased lower limit in determination of velocity of gas flow showing affinity for electron. 2 cl, 1 dwg
