Citation:
Shabnam Raayai-Ardakani. 9/15/2022. “A polynomial framework for design of drag reducing periodic two-dimensional textured surfaces.” International Journal of Heat and Fluid Flow, 98, December, Pp. 109046. Publisher's Version
 | polynomial_framework.pdf | 17.76 MB |
Abstract:
Periodic and symmetric two-dimensional textures with various cross-sectional profiles have been employedto improve and optimize the physical response of the surfaces such as drag force, superhydrophobicity, and
adhesion. While the effect of the height and spacing of the textures have been extensively studied, the effect
of the shape of the textures has only been considered qualitatively. Here, a polynomial framework is proposed
to mathematically define the cross-sectional profiles of the textures and offer a quantitative measure for
comparing the physical response of the textured surfaces with various shapes. As a case study, textured surfaces
designed with this framework are tested for their hydrodynamic frictional response in the cylindrical Couette
flow regime in Taylor–Couette flows. With the reduction in torque as the objective, experimental and numerical
results confirm that textures with height-to-half-spacing ratios of lower and equal to unity with concave profiles
offer a lower torque compared to both smooth surfaces and triangular textures. In addition, across multiple
polynomial orders, textures defined by second-order polynomials offer a wide range of responses, eliminating
the need for considering polynomials of higher orders and complexity. While the case study here is focused on
the laminar flow regime and the frictional torque, the same type of analysis can be applied to other surface
properties and physical responses as we
