The vortex drag reduction tool based on wall attachment effect has a simple structure and high reliability, but lacks systematic research on tool structural parameters. In the application of coiled tubing drilling, there are problems such as poor parameter matching and weak power output. Therefore, based on the theory of wall attached jet, this article establishes a numerical model of vortex drag reduction tools, and investigates the effects of wedge distance, sidewall angle, wedge angle, and flow channel width on the oscillation performance of the tools. The research results indicate that the wedge distance and the angle between the sidewalls affect the oscillation frequency generated by the tool by affecting the jet deflection angle, the wedge angle affects the fluid flow velocity and vortex strength in the vortex chamber, and the flow passage affects the switching of the attached wall jet by affecting the pressure on both sides of the jet port. When the splitting distance is greater than 40 mm, the angle between the sidewalls is 30°, the width of the flow passage is 4–5 mm, and the angle between the splitting tips is 15°, the oscillation performance generated by the tool is better. The research results have certain guiding significance for the reasonable matching and optimization design of the structural parameters of eddy current drag reduction tools.