Читать книгу Flow-Induced Vibration Handbook for Nuclear and Process Equipment - Группа авторов - Страница 46

A fluidelastic instability ratio is determined by calculating an effective velocity based on the velocity and density profiles and the important mode shapes. For the i^th mode, the critical velocity, U_pc, at which instability occurs, may be expressed as:

(2‐47)

where non‐uniform flow velocities and densities are represented as U_p(x) = U_pu(x) and ρ(x) = ρr(x) This is a generalized form of Eq. (2-25).