BLT QUIZ

Who introduced the concept of boundary layer theory?

• Isaac Newton
• Ludwig Prandtl
• George Gabriel Stokes
• Osborne Reynolds

The boundary layer is best defined as:

• A region where pressure remains constant
• A thin region near a solid surface where viscous forces dominate
• A region where flow is inviscid
• A region where temperature is uniform

Which of the following is NOT a type of boundary layer thickness?

• Displacement thickness
• Momentum thickness
• Thermal thickness
• Kinematic thickness

The displacement thickness accounts for:

• Loss of momentum due to viscosity
• Reduction in mass flow rate due to the boundary layer
• Energy loss in the boundary layer
• Friction drag on the surface

The momentum thickness is used to quantify:

• The average velocity in the boundary layer
• The reduction in mass flow rate
• The deficit in momentum compared to ideal flow
• The thermal effect in the boundary layer

What causes boundary layer separation?

• Favorable pressure gradient
• Constant pressure gradient
• Adverse pressure gradient
• High Mach number

The boundary layer thickness δ is proportional to:

• √(νx/U∞)
• νx/U∞
• U∞/νx
• Re²

Which statement about laminar and turbulent boundary layers is true?

• Turbulent boundary layer is thicker than laminar
• Laminar boundary layer separates earlier
• Turbulent boundary layer has lower skin friction
• Laminar boundary layer grows faster

The Reynolds number is defined as:

• Ratio of viscous force to inertial force
• Ratio of gravitational force to viscous force
• Ratio of inertial force to viscous force
• Ratio of buoyancy to viscous force

As Reynolds number increases

• Multiple Choice
• Increases
• Decreases
• Remains constant