Invesgation of the pressure loss and heat transfer and visualization of the flow in a rotating pipe

Increasing of the heat transfer in a pipe by giving it a rotating effect is a commonly used method in the literature. The rotating effect can be maintained by either locating turbulence generators in the pipe or allowing the pipe to be rotated. The experimental set up that is designed to run this work is formed with two sections. In first section a set-up including a pipe that can rotate under various rotation values is prepared for to carry out the heat transfer and pressure loss experiments. A copper pipe is preferred in this section, because of its high thermal conductivity. The length of the pipe is chosen enough long (3500 mm) for measuring the most accurate pressure losses that are caused from rotation. The second portion of the set-up is flow visualization section. The flow visualization tests are conducted by rotating a transparent glass pipe of 800 mm length. A good agreement between the measurements and visualizations is obtained after the experiments. The experiments are done under the conditions of laminar flow Re number from 500 to 2000, and turbulent flow from 3000 to 17000. The rotation value is selected as 100-150 per/min for heat transfer mesurements and 20-750 per/min for flow visualization tests. After the comparison of the results obtained from this work to the similar ones in literature, it is seen that the rotating flow that is obtained by using turbulators are more different than the rotating flow obtained by rotating the pipe itself as used in poresent work. Key Words: Rootating pipe flow, rotating flow, turbulence gernerators, heat exchanger