Submerged jet impinging asymmetrically onto a rotating surface

Mean flow and turbulence characteristics of a submerged jet impinging asymmetrically onto a rotating surface are investigated. The jet Reynolds number ranges from 1.3 × 103 to 7.9 × 103, and the rotational Reynolds number ranges from 10 × 103 to 175 × 103. The nozzle to impingement surface distance is fixed at 5d, and the nozzle axis to axis of rotation spacing is R/3 and 2R/3. Jet and rotation dominated flow regimes are identified. Spatial expansion of the jet dominated regime was found to occur when the jet Reynolds number was high, or the rotational Reynolds number was low. This was evident by a decrease in the radius of axisymmetric jet expansion from 3.4d to 2d when increasing the rotational Reynolds number from 10 × 103 to 175 × 103, keeping the jet Reynolds number constant at 1.3 × 103. The jet dominated regime was also shown to grow in axial planes sufficiently far from the rotating impingement surface. This was demonstrated by an increase in the radius of axisymmetric jet expansion from 0.85d to 3.4d in the axial planes of z/d = 0.012 and z/d = 0.125, respectively, with a jet Reynolds number of 1.3 × 103 and a rotational Reynolds number of 10 × 103. Low jet Reynolds numbers combined with high rotational Reynolds numbers were shown to aid in the formation of a mixing zone and jet deflection. When the nozzle axis to axis of rotation distance increases, the jet experiences greater deflection and the jet dominated region reduces in size. Increasing the impingement radius also enhances mixing and turbulence within the mixing zone.