A numerical study is performed on control of jet attachment by parallel controlling jet. The analysis of this study was carried out for the several combination models in the width of controlling jet nozzle over a wide range of the flow rate ratio between main jet and controlling jet. The k-ε turbulence model was chosen to calculate the velocity. The results obtained were as follows; the attachment distance of jet was increase with increasing flow ratio and flow direction changed discontinuously, and attachment distance decreased in high flow rate ratio region with increasing flow ratio. These numerical results gave fairly good agreement with the experimental results.
