The　mechanism　of　the　self-excited　oscillation　pulsed　jet　is　still　in　a　period　of　continuous　improvement,　and　the　application　breadth　and　depth　of　the　self-excited　oscillation　nozzle　are　significantly　limited　since　the　turbulent　flow　field　inside　the　self-excited　oscillation　nozzle　is　exceptionally　complex.　In　this　study,　computational　fluid　dynamics　numerical　simulation　and　experimental　research　methods　are　combined.　By　changing　the　structural　parameters　of　self-excited　oscillating　nozzles,　the　velocity　and　pressure　characteristics　of　the　self-excited　oscillating　nozzles　were　compared　and　analyzed　to　determine　the　important　factors　that　influenced　the　effect　of　pulsed　jet.　These　findings　demonstrated　that　the　periodic　expansion　and　contraction　of　the　low-pressure　vortex　ring　in　the　self-excited　oscillation　nozzle　chamber　will　cause　the　pressure　of　the　nozzle　outlet　section　to　change　periodically.　The　periodic　high-voltage　blocking　and　low-pressure　speedup　of　the　outlet　directly　correlate　with　the　pulsed　jet.　This　study　shows　the　reasonable　size　design　range　of　the　self-excited　oscillation　nozzle,　which　can　guide　the　design　and　practical　application　of　the　nozzle,　as　well　as　provide　the　theoretical　basis　for　perfecting　the　self-excited　oscillation　pulsed　jet　theory.　©　2020,　The　Brazilian　Society　of　Mechanical　Sciences　and　Engineering.