@article{MAKHILLJEAS20083112927, title = {Numerical Study of the Instability Patterns Between Counter Rotating Disks}, journal = {Journal of Engineering and Applied Sciences}, volume = {3}, number = {1}, pages = {1-6}, year = {2008}, issn = {1816-949x}, doi = {jeasci.2008.1.6}, url = {https://makhillpublications.co/view-article.php?issn=1816-949x&doi=jeasci.2008.1.6}, author = {L. Djamil}, keywords = {Rotating flows,flow between disks,shear instability,pentagonal patterns}, abstract = {The flow between counter-rotating disks for aspect ratio R/h = 7, is investigated numerically. This flow gives rise to a new instability pattern, a circular chain of vortices connected to the boundary layers trough spiral arms. The physical mechanism for this instability is elucidated: the balance between the centrifugal effects of each rotating disk results in the detachment of the boundary layer over the slower rotating disk, leading to a free shear layer in the bulk of the flow, witch becomes unstable via a Kelvin-helmholtz-type instability.} }