To address the severe erosion issue in common elbows for gas‑solid two‑phase flow,a pre‑helical pipe elbow was designed.The anti‑erosion structure of the helical pipe section was optimized using Fluent software in terms of twist angle,installation distance,and intermediate helical pipe section length,resulting in a pre‑helical pipe elbow with optimal anti‑erosion performance.The anti‑erosion effectiveness of this optimized structure was verified under varying medium flow velocities,mass flow rates,and time factors.The results show that the pre‑helical pipe elbow exhibits anti‑erosion effects only when the twist angle is between 90° and 600°,with an average improvement of 34.13% compared to the common elbow when the twist angle ranges from 210° to 420°.At twist angles of 390°,300°,and 330°,the maximum erosion rates of the pre‑helical pipe elbow are lower than those of the common elbow across the studied installation distances and intermediate helical pipe section lengths.Particularly when the installation distance is 0 mm and the intermediate helical pipe section length is 200~400 mm,the anti‑erosion effect is more significant.The optimized structural parameters are as follows:helical pipe section twist angle of 390°,installation distance of 0 mm,and intermediate helical pipe section length of 300 mm.Under these conditions,the pre‑helical pipe elbow achieves the best anti‑erosion performance,improving by 47.32% compared to the common elbow.Furthermore,although the maximum erosion rates of both this elbow and the common elbow increase with medium flow velocity,mass flow rate,and time,the maximum erosion rate of this elbow consistently remains lower than that of the common elbow,indicating that it maintains its anti‑erosion effectiveness at all times.The research results can provide a reference for the anti‑erosion structural design of elbows.
| 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 |