| With the development of hydraulic vibration technology and vibration utilization engineering, it is still attention-getting for people to study hydraulic vibration machine and its exciting regular pattern. Excitation source is the soul of hydraulic vibrating machine, and the purpose of this subject is to develop new hydraulic excitation source, to study the relevant excitation mechanism and to reveal the law of hydraulic excitation.The hydraulic wave-based classification of hydraulic exciting methods has been put forward ,which based on aggregate analysis of plenty of documents, and synthesis of hydraulic vibration technology and pulsed flow hydraulics, as well as research findings and hands-on gained by the project team for many years. This classification was helpful for people to understand the essential law of hydraulic excitation. Furthermore, a new hydraulic exciting method by using water hammer fluctuations was suggested. In the paper, the excitation mechanism of a hydraulic exciting system, which consists of a wave-exciter and a cylinder, was mainly studied as a priority research subject. According to their connecting methods, the hydraulic exciting system controlled by wave-exciter has three different types, namely normal connection, opposition method and series method. The hydraulic exciting series system, which made use of hydraulic water hammer (pressure transient flow) in fluid pressure line controlled by wave-exciter as an excitation source, was called water hammer wave exciting system. The research was mainly lied on as follows:1. The study on classification of hydraulic exciting methods based on hydraulic wave has been done by analyzing a number of relevant documents, then the author presented that the hydraulic exciting methods can be divided into two kinds. The One is an exciting method caused by flowed fluctuation, the other is an exciting method caused by pressure fluctuation.2. Study on principle of design about the parameters such as flow, pressure and power; additionally, the design principles and structural parameters on main components (wave-exciter, hydraulic cylinder). The results showed that opening-pass flow of wave-exciter must meet the needs of the largest instantaneous flow that hydraulic exciting cylinder can meet vibration conditions.3. Because the power flow is always alternating change and time-varying obviously in hydraulic exciting system, power bond graph included three control parameters on hydraulic exciting system were suggested, which enhanced physical meaning of mathematical models expressed by state equations.Moreover several universal mathematical model of hydraulic exciting system based on bond graph and Matlab/Simulink are established according to different considerations, then simulation tests were done combined with some parameters of simulated vibration screen system. These provided the theoretical support for the dynamic design of the hydraulic exciting system.4. Through theoretical study on excitation mechanism of the normal connection of hydraulic exciting system, the state-variable model of the system was established by state-space method. The pressure fluctuation rule in two chambers of hydraulic cylinder was revealed by the experiments of simulated vibration screen whose excitation frequency was controlled by the wave-exciter and regulated by the converter within authorized pressure.5. An opposition method of hydraulic exciting system was proposed and its correlation system was built. Through theoretical analysis and experimental research on block forming machine, the pressure fluctuation rules in chambers of hydraulic cylinder were obtained, and the amplitude-time curves, velocity -time curves and acceleration-time curves of vibration table were shown, which revealed excitation mechanism of the opposing hydraulic exciting system and proved that this method can produce controllable periodic pressure wave to provide exciting force. Experimental results will provide an important foundation for the design of hydraulic exciting system.6. A new hydraulic wave excitation pattern based on water hammer was proposed, and the hydraulic water hammer exciting system was built. Mathematic model of the system was established by bond graph theory, and then the simulation analysis on dynamic characteristics for it was worked out by computer. The pressure-time change rule of the water hammer exciting system was obtained by experimental research, and the frequency-domain analysis showed that the frequency of pressure fluctuation is controlled by wave-exciter. Moreover, the experimental results showed that the periodic controllable hydraulic water hammer wave generated by the system can be used as an exciting force. Finally theoretical studies were went on about structural parameters of single-point exciting and multi-exciting wave-exciter. The excitation mechanics on hydraulic water hammer has been discussed, and a new path was provided for the application of hydraulic vibrating machine.The studies and experiments of hydraulic wave exciting mechanics play an important role for the development and application of new hydraulic vibrating machine. Meanwhile, there are a certain academic value and economic significance for the development of vibration utilization engineering and development strategy on saving energy resources claimed by "Eleventh Five-Year" planning.
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