Impinging horizontal jets

Wu, Gao an and Wu, Yuan (1997). RTD of particles in an impinging stream contactor of two horizontal jets—(I) A theoretical analysis. Proc. 2nd Joint China/USA Chem. Eng. Conf. 459-462, Beijing. 

It was found that the jet will expand at such a rate that its radius equals about 0.4 times its distance from its source. Therefore, a horizontal jet inhibited by the groimd would not be well represented by this model. Also, this equation caimot be used if the jet directly impinges upon the ground. 

Jet Penetration. At the high gas velocities used in commercial practice, there are jets of gas issuing from distributor holes. It is essential that jets not impinge on any internals, otherwise the internals may be quickly eroded. Figure 14 is a graphical correlation used to determine the jet penetration length as a function of gas velocity and gas density. Jets from horizontal and downflow holes are considerably shorter than those that are pointed upward. 

When the width of the jet (calculated for free conditions) is less than the width of the room, airflow after jet impingement on a floor is similar to that in noncon-fined conditions. When the horizontally directed flow (along the particular line) reaches the wall, it is divided into two branches one following the direction of the branch with a maximum airflow and another flowing in the opposite direction. 

FIG. 14-110 Typical impingement separators, (a) Jet impactor. (b) Wave plate, (c) Staggered channels. (Blaw-Knox Food 6- Chemical Equipment, Inc.) (d) Vane-type mist extractor. (Maloney-Crawford Tank and Mfg. Co.) (e) Peerless line separator. (Peerless Mfg. Co.) (/) Strong separator. (Strong Carlisle and Hammond.) (g) Karbate line separator. (Union Catbide Corporation) (h) Type E horizontal separator. (Wright-Austin Co.) (0 PL separator. (Ingersoll Rand.) (/) Wire-mesh demister. (Otto H. York Co.)... 

Yonehara, N. and Ito, I. (1982) Cooling Charaeteristies of Impinging Multiple Water Jets on a Horizontal Plane, Teclmol Rep. Kansai University, Vol. 24, pp. 267-281. 

You, H.-Z. "An Investigation of Fire-Plume Impingement on a Horizontal Gelling 2—Impingement and Ceiling-Jet Regions." Fire Materials 9, no. L (1985) 46-56. 

T. Wang, D. Faria, LJ. Stevens, J.S.C. Tan, J.E Davidson and D.I. Wilson, Flow patterns and draining films created by horizontal and inclined coherent water jets impinging on vertical walls, Chem. Eng. Sci. 102,585-601 (2013). 

In the headbox nozzle, the suspension is accelerated to approximately machine speed. The thickness of the jet and, therefore, the amount of suspension is usually adjusted by swinging the upper wall of the nozzle. The shce at the nozzle outlet is often limited by a bar, which can be adjusted to an accuracy of ca. 1/1000 mm by means of spindles. This bar can be adjusted locally across the width this has been used or is still used in older headboxes to compensate for deviations in the cross machine weight profile of the web. The direction of the jet in the machine direction can be influenced by horizontally shifting the upper wall of the nozzle. In this way, the point and angle of impingement of the jet on the wire can be adjusted (Fig. 6.30). 

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