In order to investigate the deflection mechanism of columnar dendrite due to fluid flow the model experiments using succinonitrile-camphor alloy have been carried out. Deflection angle was found to increase with increasing flow velocity. The dendrite tip, which is parabolic in the stagnant liquid, asymmetrically deforms in the flowing liquid. Secondary dendrite arm spacing in the upstream direction is smaller than that in the downstream direction. No change in the morphology of dendrite was observed when the macroscopic thermal field was altered. The thermal and solutal fields around the columnar dendrite tip may be changed due to fluid flow. Since the change in the thermal field has little effect on the dendrite tip morphology, the change in the solutal field has an effect in a great deal on the dendrite tip morphology.
