Abstract: In order to quantitatively analyze the striking force of self-absorbing annular-air fluidic self-excited pulsed jet, and to improve the impact performance of downward-facing orifice submerged water jets, a high-frequency striking force test system of pulsed jet was used to carry out striking force tests on self-absorbing annular-air fluidic self-excited pulsed jet nozzles, and pulsating pressure signals of jets were obtained. The time-frequency characteristics of the self-absorbing pulsed jet striking force were extracted by combining the Savitzky-Golay smoothed wavelet transform and the Wigner-Ville time-frequency distribution, and the effects of different cavity lengths, working pressures, and enclosing pressures on the time-frequency distribution of the self-absorbing pulsed jet striking force energy and pulsation characteristics were studied. The test results show that: the time-frequency of the self-absorbing pulse jet striking force generated by the device is mainly concentrated in the frequency band from 30 Hz to 50 Hz, the cavity length has a greater influence on the energy distribution of the self-absorbing pulse jet striking force, when the cavity length is 18.6 mm, the self-absorbing pulse jet striking force has the largest energy density, the energy distribution of the three-dimensional surface of the existence of obvious peaks, the jet pulsation is the best effect; the time-mean value and fluctuation of the striking force of self-absorbing pulse jet The time-averaged value, fluctuation size, frequency and total energy of the self-priming pulsed jet striking force increase with the increase of the working pressure, the larger the working pressure is, the higher the peak value of the wave peak of the three-dimensional surface of the energy distribution of the self-priming pulsed jet striking force is, the better the pulsation effect of the jet is; with the increase of the peripheral pressure, the self-priming pulsed jet striking force decreases in energy density, and the pulsation effect of the jet deteriorates, and the energy of the jet is drastically reduced in the case of the peripheral pressure is larger than 0.1 MPa, and the decrease is 47%. The energy of the jet is greatly reduced when the peripheral pressure is greater than 0.1 MPa, and the reduction range is between 47.14% and 62.96%. Comparative analysis with self-excited pulsed jet and ordinary jet under the test condition of peripheral pressure of 0.1 MPa shows that the pulsation peak value and the pulsation amplitude of self-absorbing pulsed jet are 1.15 times and 1.16 times of self-excited pulsed jet and 1.25 times and 2.7 times of ordinary jet, respectively, which indicates that self-absorbing pulsed jet can continuously generate more energy under the submerged condition. submerged condition can continuously produce a better pulse jet with good pulse characteristics. The time-frequency characterization of self-absorbing pulse jet can provide a new way to improve the impact performance of downward-facing hole submerged water jet.