Fluid Mechanics: Laminar and Turbulent Flow

What characterizes laminar flow?

• Chaotic movement and eddies

• Significant pressure drop

• High velocity fluctuations

• Smooth, even flow with minimal mixing

What is the primary use of the Reynolds number?

• To predict if flow will be laminar or turbulent

• To measure fluid density

• To determine fluid viscosity

• To calculate pressure drop

In which scenario is the flow most likely to be laminar?

• Blood flow through small vessels

• Water flowing in a wide river

• Smoke rising from a chimney

• Airflow behind a fast-moving car

What is the velocity profile of fully developed laminar flow in a pipe?

• Flat across the diameter

• Parabolic, with maximum at the center

• Constant throughout

• Irregular and fluctuating

How does surface roughness affect turbulent flow?

• It has no effect

• It introduces disturbances that increase turbulence

• It smoothens the flow

• It reduces turbulence

What is the energy cascade in turbulent flow?

• Energy dissipation as heat at large scales

• Energy transfer from small to large eddies

• Energy transfer from large to small eddies

• Energy conservation across all eddies

Why is analyzing turbulent flow considered complex?

• Due to the simplicity of equations involved

• Due to the uniformity of flow

• Because of the wide range of length and time scales

• Because it only occurs in controlled environments

Which computational method resolves all turbulent eddies explicitly?

• Reynolds-Averaged Navier-Stokes

• Finite Element Analysis

• Large Eddy Simulation

• Direct Numerical Simulation

What is the main advantage of the Reynolds-Averaged Navier-Stokes method?

• It resolves all eddies explicitly

• It is the least computationally expensive

• It requires no boundary conditions

• It is suitable for all types of flow

What role does engineering intuition play in fluid dynamics?

• It is unnecessary due to precise calculations

• It helps in selecting appropriate models and techniques

• It replaces the need for computational methods

• It is only useful in theoretical scenarios