The length of the impactor is generally about one meter according to the current application of all kinds of impactors.As the existing impactor increases the distance between the stabilizer and the drill bit, it will cause the theoretical build slope and the lateral force of the drill bit to decrease when it is used in connection with the drill bit. This will in turn affects the drilling deviation section.In this regard, the multi-dimensional impactor with built-in drill bit can effectively solve this problem.Firstly, in order to maximize the performance of the multi-dimensional impactor with built-in drill bit and reduce the pressure loss, the PB (Plackett-Burman) screening test design was adopted to conduct screening tests on the internal parameters of the impactor. The effect of each parameter on the tool performance was as follows: Jet channel width > inlet area > Outlet area > length of oscillating cavity > width of double feedback channel > curvature radius of wall attached surface > wedge Angle. Then, BBD (Box-Behnken design) response surface method was used to provide an in-depth analysis of the top three significant impact parameters.The optimized combination of the internal structure of the multi-dimensional impacter with built-in drill bit was obtained as follows: the inlet area is 1 203.416 mm2, the jet channel width is 14 mm, and the outlet area is 455 mm2. Finally, the effectiveness of the optimization method was verified by the simulation of Fluent software, which met the design requirements.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |