# Dynamic Simulation Model and Performance Optimization of a Pressurized Pulsed Water Jet Device
###### Abstract
[31] and [PERSON] et al. [32] conducted additional research on UMPWJs, exploring erosion performance based on micro-morphology and varying operating parameters. Due to the high-frequency characteristics of ultrasonic waves, the study concentrated on UMPWJ with a pulse frequency exceeding 20 kHz, while PWJs with a lower pulse frequency were not considered. Many scholars highlighted the distinct benefits of utilizing a PWJ with a low pulse frequency for rock breaking. [PERSON] et al. [33] conducted a simulation of the rock breaking process using a PWJ and observed that a water-cushion effect would emerge and reduce the rock breaking efficiency under a high pulse frequency. [PERSON] et al. [34] demonstrated that the PWJ has a high cutting capacity with a low range of pulse frequencies by conducting the rock cutting test under different hydraulic parameters. An interrupted pulsed water jet (IPWJ) has been proposed and widely studied in order to achieve the threshold pressure required for rock breaking and to cater to the demands of low-pulse-frequency applications. The IPWJ employs a slotted disk to periodically divide the continuous water jet into distinct water slugs. This method is widely regarded as the most convenient for generating intermittent water jets with easily controllable pulse parameters for practical applications [35]. [PERSON] et al. [36; 37] found that the pulse frequency and the pulse duration affected the formation and development of the failure zone, respectively, and the pulse frequency and pulse duration jointly promoted internal damaging of the rock. To reveal the mechanical mechanism of rock breaking by IPWJs, [PERSON] et al. [12] simulated the propagation of stress waves in the rock through the method of smooth particle hydrodynamics. [PERSON] et al. [38; 39] obtained the flow field structure of an IPWJ by numerical simulation and testing of morphology capture. They revealed that the flow field structure of an IPWJ was associated with impact performance. [PERSON] et al. [40] studied the effect of disc-to-nozzle distance and disc-to-target distance on rock breaking, aiming to improve the efficiency of IPWJs for rock breaking. Compared with SOPWJs and UMPWJs, IPWJs have a unique advantage for rock breaking, but the pulse pressure depends on the pump pressure. To enhance the potency and destructive capability of the PWJ for rock breaking, the rated pump pressure needs to be further increased due to the high compression strength of rocks [41]. However, the cost of increasing rated pump pressure is much higher than that of equipment manufacturing and maintenance, thereby constraining the development and utilization of PWJs. For better application of PWJs for rock breaking, a pressurized pulsed water jet (PPWJ) device was developed by [PERSON] et al. [42] and proved that the rock breaking capability of a PPWJ surpasses that of a CWJ. A PPWJ with higher pulse pressure at lower input pressure can be created without requiring ultra-high-pressure equipment. To improve the performance of the device, a dynamic simulation model was established to obtain its dynamic characteristics and predict the variation curves of jet pressure. Meanwhile, the effect of key structural parameters of the device on the pulse parameters was analyzed, and the device was optimized to further increase rock breaking efficiency on that foundation.