Research on Generation Principle and Parameter Influencing Law of Continuous Wave Pulser

Continuous wave pulser is a core component of the measurement-while-drilling (MWD) tool. In order to discuss the principle of pressure wave generation of the continuous wave pulser and the influencing laws of its parameters, a numerical simulation model of flow field of the continuous wave pulser was established based on relevant theories and methods of computational fluid dynamics (CFD), which was used to simulate the characteristics of flow field of the continuous wave pulser. The numerical simulation results showed that, in the cyclic reciprocating switching process of the rotor, the continuous wave pulser will generate flow wave (the upstream and downstream phase positions are same) and pressure wave (the upstream and downstream phase positions are opposite)|the amplitude of pressure wave is related to the pulser control parameters, which will decrease with the increase of frequency and stator-rotor clearance|the amplitude of pressure wave is related to the hydraulic parameters for drilling operation, which will increase with the fluid discharge capacity and density, and the influence of fluid viscosity on the amplitude is negligible. The study results will has theoretical guiding significance for the field application of continuous wave pulsers.