A　novel　self-excited　oscillating　mixer　is　developed　for　the　descaling　of　strip　steel,　which　synthesizes　the　post-mixed　abrasive　water　jet　and　self-excited　oscillation.　The　realizable　k-e　model　is　selected　to　investigate　the　effects　of　different　abrasive　entrance,　inlet　pressure,　mixing　chamber　diameter,　and　length　on　the　jet　characteristics.　Meanwhile,　the　effects　of　different　inlet　pressure　and　target　distance　on　the　outlet　velocities　for　two　kinds　of　mixers　(including　the　developed　mixer　and　conventional　post-mixing　mixer)　with　or　without　abrasive　jet　are　investigated　through　simulation.　Experiment　as　well　as　simulation　results　exhibited:　(1)　The　oblique　abrasive　entrance　can　accelerate　the　mixture　of　water　and　abrasive　due　to　its　larger　turbulent　kinetic　energy,　and　its　outlet　velocity　is　larger　than　that　of　radial　and　axial　abrasive　entrances.　(2)　For　the　developed　mixer,　the　outlet　velocity　is　preferable　when　the　mixing　chamber　diameter　is　about　40-50　mm　and　the　mixing　chamber　length　is　20　mm.　(3)　The　descaling　efficiency　of　the　developed　mixer　is　superior　to　that　of　conventional　post-mixing　mixer.　The　research　will　lay　foundation　to　optimize　the　structure　of　self-excited　oscillating　mixer　for　the　descaling　of　rusty　steel.