72th Annual Meeting of the APS Division of Fluid Dynamics (November 23, 2019 — November 26, 2019)

V0088: Effect of pressure gradients on a confined turbulent plane wake

Authors

• Chitrarth Lav, University of Melbourne
• Jimmy Philip, University of Melbourne
• Richard Sandberg, University of Melbourne

DOI: https://doi.org/10.1103/APS.DFD.2019.GFM.V0088

Efficiency of gas turbines is directly related to the loss produced; minimising loss leads to increase in efficiency. Once such source of loss is from wake mixing under the presence of pressure gradients. We simply the problem by exposing a wake to a region of constant pressure gradients to understand the underlying physics. Performing direct numerical simulations (DNS), the obtained results show that a wake in favourable pressure gradient enhances wake mixing, drawing energy from the turbulence to accelerate the flow and consequently reducing the loss by lowering the amount of entropy produced. An adverse pressure gradient on the other hand draws energy from the mean to the turbulent scales, increasing the amount of entropy produced and thus the loss.