INTERMITTENT PATTERNS IN MIXED CONVECTION

We have performed a Laser Doppler anemometry study of the mixed convec tive flow of water in a horizontal, rectangular duct of 4.15 mm height , 115 mm length and 15.05 mm width. This study has revealed a particul ar flow regime that lies approximately between 1920 < Ra < 2080 and 0. 45 < Re < 0.75, in which only irregular and intermittent flow structur es are observed. Small excursions in Re or Ra beyond these bounds resu lt in the stabilization of either longitudinal or transverse rolls.