Abstract
The main objective of this paper is to study the effects of turbulence in collecting pressure tap measurements under high Reynolds number flows. The Reynolds numbers have been determined experimentally for free delivery of a 2-bladed fan to range from its free delivery condition to the shutoff condition respectively, 10540 < ( < 33,612. For internal flow, the results indicate that the experimental rig is experiencing turbulence. The fan performance curve was determined numerically under steady state conditions and follows the trend of the experimental results. The CAD simulations were drawn to represent the actual experiment. The boundary conditions and initial conditions are intended to model inherent properties within the experiment and environmental conditions. These preliminary results obtained from SOLIDWORKS flow simulation provide insight on the physics of the flow within the test rig. Due to the high Reynolds numbers in the pipe, we assume that turbulence exists; furthermore, the flow trajectories and vorticity contours have confirmed such behavior. Also, with the simulation we are able to pinpoint the locations where the vortices are concentrated. These pockets of vortices present a possible problem in accurately measuring pressures at the taps. The key components in the loop, such as the venturi flow meter, butterfly valve and the axial fan, have been our primary focus in this study. The flow characteristics around these items are studied extensively. We were able to find that the butterfly valve introduces wakes when the valve is being closed. Additionally, the venturi flowmeter also can have effects of vorticity at certain fan conditions. We will expand this work to include higher Reynolds numbers up to about 90,000. The interest in this is to determine if the pressure tap measurements will show greater variations in the pressures.
| Original language | English |
|---|---|
| Title of host publication | Unknown book |
| Pages | 35-42 |
| Volume | Volume 17 |
| State | Published - 2019 |