草地蝗虫吸捕机吹吸式吸嘴的设计

Design of blowing-suction typed suction mouth of grassland locust■suction trapping machine

针对原草地蝗虫吸捕机采用直吸式吸嘴，吸捕率低。以度蝗虫在吸嘴内壁上撞击、破碎等问题，在对原直吸式吸嘴，特别是在对吹吸气流进行理论分析的基础上，结合蝗虫在吸捕时的跳跃躲避特性以度对蝗虫悬浮速度的实验测定，设计了吹吸式吸嘴，并对吹吸式吸嘴与直吸式吸嘴进行了对比试验。试验表明：（1）吹吸式吸嘴可将吸口气流速度从原来直吸的20m／s降低为现在的14m／s，可减轻后续设备的负荷。（2）与具有相同吸口气流速度的直吸式吸嘴相比，其轴向、径向吸捕距离分别延长到115～2倍。负压吸捕区增大到2～3倍，能够对更大范围内的蝗虫进行有效吸捕，提高吸捕率。（3）获得了影响回旋气幕形成各主要因素的合理参数，为草地蝗虫吸捕机的设计与改进提供了理论依据。

Aimed at the problems of low suction trapping rate, ramming and crashing of locusts against the inner wall of suction mouth of the straight typed suction mouth being adopted by the original grassland locust suction trapping machine, on the bases of carrying out theoretical analysis on the original straight typed suction mouth and especially on the blowing suction airflow, the blowing-suction typed suction mouth was designed with the combination of the jumping elusion characteristics of locust while being trapped and of the experimental measuring determination on the suspension speed of locust. A contrast experiment was carried out on the blowing-suction typed suction mouth and the straight suction typed suction mouth, the experiment showed that： （1） The blowing-suction typed suction mouth could lower the airflow speed at the opening of suction mouth from the original 20m/s to the present 14m/s, and could lighten the loading of the following up devices. （2） While compared with the straight suction typed suction mouth that possesses similar airflow speed at the opening of suction mouth, the suction trapping distance in the axial and radial di- rections could be extended respectively to 1.5 to 2 times, the negative pressured suction trapping area could be enlarged to 2 to 3 times that could conduct effective suction trapping and raise the suction trapping rate. （3） The reasonable parameters of each main factor that influencing the formation of circling-round air-curtain was obtained. All of this provided theoretical basis for the design and improvement of the grassland locust suction trapping machine.