WorksheetsDay 42-Nov 1-Worksheet-Diploma-Boundary layer theory
Total questions: 15
Worksheet time: 12mins
In the boundary layer, velocity becomes 99 % of free-stream velocity at a distance known as —
(a)
The velocity profile in a laminar boundary layer is —
(a)
In turbulent boundary layer, the velocity distribution is approximately —
Linear
Logarithmic
Uniform
Parabolic
At what Reynolds number does laminar flow generally become turbulent on a flat plate?
Re = 2 × 10⁴
Re = 5 × 10⁵
Re = 10⁶
Re = 10⁷
Which of the following layers exists within the turbulent boundary layer due to high viscous effects?
Transition layer
Outer layer
Laminar sub-layer
Wake region
In a laminar flow over a flat plate, boundary-layer thickness (δ) varies with distance x as —
δ ∝ x¹/⁵
δ ∝ x¹/²
δ ∝ x
δ ∝ x²
Boundary-layer separation occurs when —
∂u/∂y > 0
∂u/∂y = 0
∂u/∂y < 0
The region near the solid boundary where viscous effects dominate is called (a) .
The displacement thickness represents the distance by which the (a) is displaced away from the wall due to boundary layer.
The ratio of displacement thickness to momentum thickness is called (a) .
According to Prandtl, pressure across a boundary layer is nearly (a) .
In accelerated flow, the pressure gradient is (a) .
At the separation point, both pressure and velocity gradients become (a) at the point of detachment
Match the following
Laminar flow
Parallel streamlines
Turbulent flow
Occurs near trailing edge
Laminar sublayer
Linear velocity profile
Boundary separation
Positive pressure gradient
The inner region of a boundary layer is also called the (a) region.
