Impact of auxiliary nozzles pitch change on flying situation of weft yarn

For better understanding the flying situation of weft yarn during air-jet weft insertion and minimizing the fluctuation of weft yarns,an air index tester consisting of the main components of weft insertion system and a high speed camera system was adopted,and the weft yarn flying actual situation in the unconventional shaped reed was filmed and analyzed with a dedicated image software.The variation of the weft flying speed and the fluctuation of the flying weft yarn in the reed slit were tested when the auxiliary nozzles pitch was changed.It was found that when the auxiliary nozzles pitch was 65mm,more stable and less fluctuated flying of the weft yarn was observed as compared with the auxiliary nozzles pitch of 75mm and 85mm.