Cheng-Yeh Li, Jui-Hsiang Kao^*

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.3, pp. 2277-2304, 2024, DOI:10.32604/cmes.2023.030215

Abstract The performance of a water jet propulsion system is related to the inlet duct, rotor, stator, and nozzle. Generally, the flow inlet design must fit the bottom line of the hull, and the design of the inlet duct is often limited by stern space. The entire section, from the rotor to the nozzle through the stator, must be designed based on system integration in that the individual performance of these three components will influence each other. Particularly, the section from the rotor to the nozzle significantly impacts the performance of a water jet propulsion system. This study focused on nozzle… More >

Dengfeng Su¹, Zizheng Jia^1,*, Qiang Zhu¹, Zhengguo Li¹, Banghong Chen¹, Dandan Zheng²

Structural Durability & Health Monitoring, Vol.17, No.3, pp. 209-224, 2023, DOI:10.32604/sdhm.2022.021257

Abstract Damage is one of the most important characteristics of rock failure. Studying the damage mechanism of rock blasting under the guiding effect of the water jet slot and revealing the mechanism of controlled blasting with water jet assistance are crucial. In this study, a rock-like material was chosen as the research object for the calibration experiment of the numerical model. The numerical simulation models were then established by ANSYS/LS-DYNA, and the blast-induced damage mechanism under the guiding effect of the water jet slot was analyzed according to the blasting theory. The results indicated that explosive energy accumulates toward the direction… More > Graphic Abstract

Zhibin Zhang^1,2, Yongjun Gong^1,*, Liping Zhang³, Min Xv², Gaofeng Shang⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.5, pp. 1363-1371, 2022, DOI:10.32604/fdmp.2022.019746

Abstract The effects of oblique submerged scouring jets on sand beds with various particle sizes have been studied experimentally. In particular, a total of 25 experiments have been carried out to explore the influences of the jet angle and application time on the considered submerged sand beds. Test results conducted with a specially-designed device have shown that the scouring efficiency attains a maximum when the inclination angle is in the range between 15° and 20° and then it decreases when the inclination angle becomes higher. More >

I. Černý^1,2, D. Mikulová¹

Structural Durability & Health Monitoring, Vol.6, No.1, pp. 43-52, 2010, DOI:10.3970/sdhm.2010.006.043

Abstract Alternative methods of material machining like electro-erosive or water jet cutting, respectively, represent modern technologies, which are perspective to be used as final end-to-shape operations due to their possibilities of automatization and cutting precision. The paper contains results of an investigation of resistance of an aircraft AISI 4340 steel against fatigue loading performed using specimens loaded by three point bending at ambient temperature and standard laboratory conditions. Results of fatigue tests of specimens with surface after electro-erosive and water jet cutting, respectively, are presented, whereas in the latter case, areas of water jet incidence and outfall are studied separately. The… More >

M . Annoni¹, F. Arleo¹, M. Guagliano^1,2

Structural Durability & Health Monitoring, Vol.6, No.1, pp. 1-16, 2010, DOI:10.3970/sdhm.2010.006.001

Abstract This work investigates the possibility to perform Water Jet Peening (WJP) by means of a standard Water Jet (WJ) cutting plant. The experimentation is carried out on 39NiCrMo3 specimens with the aim to find out the best working conditions of two different methods: the "in air WJP" and the "submerged WJP". Comparisons between the two methods and to previous experimentations in the reference literature are also presented. More >

Dengfeng Su¹, Yong Kang^1,2,*, Xiaochuan Wang², andan Zheng¹, DongyangLi¹, Binyuan Yan¹, Fuwen Yan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.111, No.5, pp. 375-393, 2016, DOI:10.3970/cmes.2016.111.375

Abstract Tunnel though coal seam is one of the most difficult tunnels since its risk of coal and gas outburst and the complex geological conditions. According to the directional cutting of water jet and the characteristic of the coal seam and rock mass, this paper presents a new method of tunnelling though coal seam assisted by water jet slotting, which can be divided into improving permeability of coal seam and directional cracking in the rock mass. The mechanism of improving permeability of coal seam was stated, and the crack criterion of rock during blasting was established based on fracture theory. Then,… More >

Yong Liu¹, Jianping Wei^2,3

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.3, pp. 221-240, 2015, DOI:10.3970/fdmp.2015.011.221

Abstract Although the socalled percussion-pulsed-water jet technique is currently recognized as an effective means for breaking hard rocks, it can’t be extensively employed due to insufficient systematic research on the related flow-field structure. Considered as one of the rock breaking technologies with the highest potential of development and application, this method is characterized by water hammer effects, a high-frequency impact pressure and high-speed side flows. The typical (impact and extrusion) pistons used for this technique collide several times to form the multi-pulsed jet. Here we analyze these features through a combined experimental-numerical investigation. The number of pulses and kinetic parameters of… More >

Shuce Zhang¹, Xueheng Tao^1,2,3, Jinshi Lu^1,2, Xuejun Wang^1,2, ZhenhuaZeng⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.2, pp. 143-155, 2015, DOI:10.3970/fdmp.2015.011.143

Abstract Three different kinds of nozzles, normally used in industrial processes for the cleaning of material surface by means of water jets at high pressure (a Cylindrical Contracting, a Taper Contracting and Stepped nozzle), are numerically simulated with the express intent to optimize the related efficiency (cleaning effectiveness). Although some of them are found to display interesting properties, simulation results indicate that a helix nozzle displays the best jetting performances. It is shown that, as compared to improvements obtained by simply changing the jetting angle, revolving the fluid released from the helix nozzle can be used to create a grinding wheel… More >