New unsteady boundary layers over a long thin cylinder

作者：Fang Tiegang^*

来源：Meccanica, 2015, 50(12): 2907-2918.

DOI：10.1007/s11012-015-0177-1

• Unsteady boundary layer
• Cylinder
• Leading edge accretion
• Leading edge ablation

In this paper, a new family of unsteady boundary layers over a long cylinder was investigated. This new class of unsteady boundary layers involves the flows over a long thin cylinder, whose leading end is either accretion or ablation at a certain rate. Using dimensionless variables, the governing partial differential equations are transformed into an ordinary differential equation, which was solved with a shooting method numerically. Under special cases, the solution can be solved explicitly. Solution domain was estimated and calculated numerically. It is found that a unique solution exists for accretion, while two solutions can exist for ablation. For other ablation parameters, there are no solutions. This new type of unsteady boundary layers over a cylinder enriches the literature on flow passing a cylinder and can provide benchmark problems for validating numerical code of computational fluid dynamics.

• 出版日期2015-12