Influence of Mixing Efficiency in Y Shape Microchannels by Pulsing Flows
| Autor: | Ching-Wen LI, 李景雯 |
|---|---|
| Rok vydání: | 2013 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 101 A pulsing flow is a flow with a frequency-dependent flow velocity which can be used to enhance the mixing efficiency of micro-channels that originally is governed by the flow diffusive mechanism. In this paper, we investigated the utilization of the characteristics of pulsing flows with a varying flow velocity to enhance the flow mixing efficiency at low Reynolds number region. A Y-shaped micro-channel was used. Two pulsing flows having the same flow rate with a 180° phase angle were injected into the two inlets of the channel. A numerical investigation was performed to study the mixing efficiency of the channel with a square and a triangular pulsing flow. The results showed that a high pulsing flow frequency and a low flow rate reduced the mixing length of the channel. Moreover, under the same flow frequency and flow rate, the mixing efficiency of a square-wave flow was almost 1.7 times that of a triangular-wave flow. Finally, a nondimensional analysis was performed to examine the relationship between the mixing efficiency and the position of the flow in the channel. The relationship was nondimensionalized with respect to the flow frequency and the average flow velocity. It was found that a universal curve can be obtained for the mixing efficiency of the channel, regardless of the flow frequency and the flow rate. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|