Trickle flow

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As Rinnsalströmung ( English rivulet flow ) will be referred to a flow having a free surface along a body contour which a particularly low volume flow has and has certain properties. In contrast to the film flow , these are often meandering or oscillating flows. Even tearing film flows are referred to as rivulets after the opening point.

For rivulet flows, different flow forms arise depending on the volume flow. In the case of very low volume flows, which nevertheless do not lead to the flow breaking off, rivulets are formed that run in a straight line and laminar . This form of trickle flow can also be viewed as a special case of film flow. With a further increase in the volume flow, the width and height of the trickle initially increase until meanders form at a certain volume flow . The hysteresis of the contact angle is seen as the most likely cause for this . Exceeding a further critical value for the volume flow leads to a pendulous or oscillating trickle; several rivulets can form.

Individual evidence

  1. ^ A b P. Schmuki, M. Laso: On the stability of rivulet flow . In: Journal of Fluid Mechanics . tape 215 , 1990, pp. 125-143 , doi : 10.1017 / S0022112090002580 .
  2. ↑ A. Doniec: Flow of a laminar liquid film-down a vertical surface . In: Chemical Engineering Science . tape 43 , no. 4 , 1988, pp. 847-854 , doi : 10.1016 / 0009-2509 (88) 80080-0 .
  3. ^ JB Culkin, SH Davis: Meandering of water rivulets . In: AIChE Journal . tape 30 , no. 2 , 1984, p. 263-267 , doi : 10.1002 / aic.690300214 .
  4. ↑ Mohamed S. El-Genk, Hamed H. Saber: Minimum thickness of a flowing down liquid film on a vertical surface . In: International Journal of Heat and Mass Transfer . tape 44 , no. 15 , August 2001, p. 2809-2825 , doi : 10.1016 / S0017-9310 (00) 00326-4 .