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A computational efficient modelling of laminar separation bubbles
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Maughmer, Mark D. Dini, Paolo |
| Copyright Year | 1990 |
| Description | In predicting the aerodynamic characteristics of airfoils operating at low Reynolds numbers, it is often important to account for the effects of laminar (transitional) separation bubbles. Previous approaches to the modelling of this viscous phenomenon range from fast but sometimes unreliable empirical correlations for the length of the bubble and the associated increase in momentum thickness, to more accurate but significantly slower displacement-thickness iteration methods employing inverse boundary-layer formulations in the separated regions. Since the penalty in computational time associated with the more general methods is unacceptable for airfoil design applications, use of an accurate yet computationally efficient model is highly desirable. To this end, a semi-empirical bubble model was developed and incorporated into the Eppler and Somers airfoil design and analysis program. The generality and the efficiency was achieved by successfully approximating the local viscous/inviscid interaction, the transition location, and the turbulent reattachment process within the framework of an integral boundary-layer method. Comparisons of the predicted aerodynamic characteristics with experimental measurements for several airfoils show excellent and consistent agreement for Reynolds numbers from 2,000,000 down to 100,000. |
| File Size | 5370060 |
| Page Count | 166 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19900015975 |
| Archival Resource Key | ark:/13960/t6c29sw3k |
| Language | English |
| Publisher Date | 1990-07-01 |
| Access Restriction | Open |
| Subject Keyword | Fluid Mechanics And Heat Transfer Low Reynolds Number Turbulence Momentum Airfoils Iteration Design Analysis Boundary Layer Separation Thickness Bubbles Mathematical Models Aerodynamic Characteristics Prediction Analysis Techniques Boundary Layers Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
