Abstract
The turbulent characteristics of self-rotating self-cleaning plastic twisted-tape-inserted tube were studied experimentally by using a 2D frequency shifting Laser Doppler Velocimeter (LDV) system. The results show the behavior of fluid flow in the self-rotating self-cleaning plastic twisted-tape-inserted tube is different from that in the normal smooth tube. The twisted-tape makes flow field change ultimately. The fluid flow in self-rotating self-cleaning twisted-tape-inserted tube is in spiral motion following the self-rotating twisted tape. In the annular area near the tube wall the axial velocity is about 25% higher than that of the central area of the tube, and the axial turbulence intensity is about 68% stronger than that of the smooth tube. The fluid flow has distinct tangential motion, the tangential velocity increases as the radius increase; the tangential turbulence is very high, and the tangential turbulence intensity is 10 times than the axial turbulence. These turbulent characteristics of fluid flow for self-rotating self-cleaning twisted-tape-inserted tube will provide experimental support for the further theoretical research of convection heat transfer enhancement mechanism.
| Original language | English |
|---|---|
| Pages (from-to) | 17-21 |
| Number of pages | 5 |
| Journal | Gao Xiao Hua Xue Gong Cheng Xue Bao/Journal of Chemical Engineering of Chinese Universities |
| Volume | 19 |
| Issue number | 1 |
| State | Published - Feb 2005 |
Keywords
- Experimental investigation
- Heat transfer enhancement mechanism
- Laser Doppler velocimeter (LDV)
- Self-rotating self-cleaning twisted-tape-inserted tube
- Turbulent characteristics