Convergence Criterion for a Far-Field Drag Prediction and Decomposition Method

AIAA Journal ◽  
2011 ◽  
Vol 49 (12) ◽  
pp. 2814-2818 ◽  
Author(s):  
Martin Gariépy ◽  
Jean-Yves Trépanier ◽  
Christian Masson
Author(s):  
Martin Gariepy ◽  
Jean-yves Trepanier ◽  
Benoit Malonin ◽  
Christian Masson

Author(s):  
Li Li ◽  
Junqiang Bai ◽  
Xiaolong He

In the aerodynamic shape design, the drag prediction has always been an extremely challenging mission for the exploration of a configuration. As for the more complex configurations, it is especially desired to the availability of a highly accurate and reliable aerodynamic numerical solution. For improving the drag prediction accuracy and promoting the aerodynamic shape designs, firstly, the characteristics of drag prediction based on far-field drag method and near-field drag method is analyzed and compared. Also, the merits and demerits of defining axial velocity defect with the current main far-field drag prediction approaches is summarized, which promotes the building of the improved method of axial velocity defect and the improved far-field drag prediction and decomposition approach. Moreover, during the establishment of the drag decomposition method, it is necessary to judge and decide on the selection of the drag region. Therefore, the discussions on the sensitivity of the relevant parameters are fulfilled. Furthermore, based on the far-field drag prediction and decomposition method constructed, the aerodynamic performance research of Common Research Model wing-body configuration is launched. The results show that it can effectively observe and analyze the changes in drag components, their impact on the total drag and the contribution percentage. Finally, combining the far-field drag prediction and decomposition method proposed in this paper with a gradient-based aerodynamic shape optimization design system, the aerodynamic shape optimization designs are studied with CRM wing-body configuration. The results can not only directly analyze the detailed change of the visualized drag region, but also can obtain the more accurate total drag and lift-to-drag ratio of the optimized configuration by removing the spurious drag.


2014 ◽  
Vol 51 (6) ◽  
pp. 1953-1958 ◽  
Author(s):  
Troy Snyder ◽  
Alex Povitsky

2011 ◽  
Vol 48 (5) ◽  
pp. 1658-1670 ◽  
Author(s):  
David Hue ◽  
Sebastien Esquieu

2014 ◽  
Vol 56 (2) ◽  
pp. 192-208 ◽  
Author(s):  
YINWEI LIN ◽  
TZON-TZER LU ◽  
CHA’O-KUANG CHEN

AbstractWe propose a new Adomian decomposition method (ADM) using an integrating factor for the Emden–Fowler equation. With this method, we are able to solve certain Emden–Fowler equations for which the traditional ADM fails. Numerical results obtained from testing our linear and nonlinear models are far more reliable and efficient than those from existing methods. We also present a complete error analysis and a convergence criterion for this method. One drawback of the traditional ADM is that the interval of convergence of the Adomian truncated series is very small. Some techniques, such as Pade approximants, can enlarge this interval, but they are too complicated. Here, we use a continuation technique to extend our method to a larger interval.


AIAA Journal ◽  
2015 ◽  
Vol 53 (11) ◽  
pp. 3414-3429 ◽  
Author(s):  
Hélène Toubin ◽  
Didier Bailly

Sign in / Sign up

Export Citation Format

Share Document