A weft insertion device includes a first main nozzle and a second main nozzle that is arranged upstream from the first main nozzle in a weft insertion direction and is configured to function as an auxiliary main nozzle. The first main nozzle is connectable to a first valve device by a first piping. The second main nozzle is connectable to a second valve device by a second piping shorter than the first piping. The weft insertion device is configured to supply compressed air to each main nozzle with each valve device being in an open state over a jet period from a predetermined jet starting timing. In a predetermined initial jet period that begins at the jet starting timing, an operating state of the second valve device is put into a small flow rate state, in which a flow rate smaller than a steady flow rate is supplied.

The present invention relates to methods, apparatuses, and systems for controlling the density of a fluid near a functional object in order to improve one or more relevant performance metrics. In certain embodiments, the present invention relates to forming a low density region near the object utilizing a directed energy deposition device to deposit energy along one or more paths in the fluid. In certain embodiments, the present invention relates to synchronizing energy deposition with one or more parameters impacting the functional performance of the object.

A weft insertion device includes a first main nozzle and a second main nozzle that is arranged upstream from the first main nozzle in a weft insertion direction and is configured to function as an auxiliary main nozzle. The first main nozzle is connectable to a first valve device by a first piping. The second main nozzle is connectable to a second valve device by a second piping shorter than the first piping. The weft insertion device is configured to supply compressed air to each main nozzle with each valve device being in an open state over a jet period from a predetermined jet starting timing. In a predetermined initial jet period that begins at the jet starting timing, an operating state of the second valve device is put into a small flow rate state, in which a flow rate smaller than a steady flow rate is supplied.