Wake-Model Effects on Induced Drag Prediction of Staggered Boxwings
AbstractFor staggered boxwings the predictions of induced drag that rely on common potential-flow methods can be of limited accuracy. For example, linear, freestream-fixed wake models cannot resolve effects related to wake deflection and roll-up, which can have significant affects on the induced drag projection of these systems. The present work investigates the principle impact of wake modelling on the accuracy of induced drag prediction of boxwings with stagger. The study compares induced drag predictions of a higher-order potential-flow method that uses fixed and relaxed-wake models, and of an Euler-flow method. Positive-staggered systems at positive angles of attack are found to be particularly prone to higher-order wake effects due to vertical contraction of wakes trajectories, which results in smaller effective height-to-span ratios than compared with negative stagger and thus closer interactions between trailing wakes and lifting surfaces. Therefore, when trying to predict induced drag of positive staggered boxwings, only a potential-flow method with a fully relaxed-wake model will provide the high-degree of accuracy that rivals that of an Euler method while being computationally significantly more efficient. View Full-Text
Share & Cite This Article
Schirra, J.; Bissonnette, W.; Bramesfeld, G. Wake-Model Effects on Induced Drag Prediction of Staggered Boxwings. Aerospace 2018, 5, 14.
Schirra J, Bissonnette W, Bramesfeld G. Wake-Model Effects on Induced Drag Prediction of Staggered Boxwings. Aerospace. 2018; 5(1):14.Chicago/Turabian Style
Schirra, Julian; Bissonnette, William; Bramesfeld, Götz. 2018. "Wake-Model Effects on Induced Drag Prediction of Staggered Boxwings." Aerospace 5, no. 1: 14.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.