Reduction of surface friction drag in scramjet engine by boundary layer combustion

Bubbly turbulent drag reduction is a boundary layer effect.

In turbulent Taylor-Couette flow, the injection of bubbles reduces the overall drag. On the other hand, rough walls enhance the overall drag. In this work, we inject bubbles into turbulent Taylor-Couette flow with rough walls (with a Reynolds number up to 4 x 10(5), finding an enhancement of the dimensionless drag as compared to the case without bubbles. The dimensional drag is unchanged. As in...

Surface Friction and Boundary Layer Thickening in Transitional Flow

Scramjet Combustion Processes

Research into hypersonic flow phenomona has been conducted by numerous groups within Australia for over 40 years. The genesis of all the modern day work can be traced back to the return of the then Dr Ray Stalker from England, to take a faculty position in the Physics Department of the Australian National University, Canberra, in 1962. Dr Stalker had a keen interest in the aerodynamics of bodie...

Drag reduction in a flat-plate turbulent boundary layer flow by polymer additives

This paper presents a theoretical study on the velocity distribution and the friction factor of boundary layer flows with polymer additives starting from the concept of “stress deficit.” A novel method of order of magnitude analysis is developed, which converts the governing equations of boundary layer flow into a solvable ordinary differential equation, thus the total shear stress distribution...

Boundary-layer friction in midlatitude cyclone