Laminar Boundary Layer Theory - Module 3

A: Option A tracks the δ ~ x/√Re_x relationship; doubling velocity doubles Re_x and pulls thickness down by √2. Option B is a common first instinct when thinking in linear terms, but laminar layers don't scale that way. Option C ignores the velocity term sitting inside Reynolds number. Option D sounds physical if you're picturing turbulence, yet laminar momentum diffusion gets thinner as inertial forces rise.

A: Option A matches the symptom directly; freestream turbulence trips laminar layers early even when geometry is clean. Option B nudges Reynolds number but not by a factor of two. Option C changes the x-location of transition, not the critical Reynolds number itself. Option D creeps in from compressible flow theory, yet Mach 0.1 doesn't drive transition behavior.

A: Option A reflects how standards are applied in regulated projects; audits look for contractual compliance first, then managed change. Option B sounds defensible from a technical purity angle, but it bypasses contract law. Option C imports theory assumptions without regard to procurement terms. Option D feels pragmatic yet has no standing in either the standard or the contract.

A: Option A uses the correct average laminar correlation over the plate length. Option B confuses local peak values with the averaged coefficient. Option C drags in a turbulent formula that drops Cf too far. Option D flips intuition; laminar shear is lower than turbulent for the same Reynolds number.

A: Option A sets the boundary condition; without low turbulence, nothing downstream matters. Option B is useful but only after laminar flow is credible. Option C diagnoses drag effects, not laminar integrity. Option D matters for data quality, yet it won't rescue a tripped boundary layer.

A: Option A explains both thickening and reversal; laminar layers lack momentum to fight rising pressure. Option B would push the flow turbulent, not reverse it. Option C can distort profiles but won't create real separation. Option D tweaks Reynolds number yet doesn't generate a pressure gradient.

A: Option A follows the Reynolds number logic; higher viscosity lowers Re_x and grows the layer. Option B sounds intuitive if you're thinking of damping, but laminar theory says otherwise. Option C ignores viscosity's explicit role. Option D mixes up viscosity effects with turbulence triggers.

A: Option A aligns with audit expectations: comply with what's cited, then manage change formally. Option B feels safer but can violate contract scope. Option C underestimates how auditors treat referenced guidance. Option D relies on outcome-based judgment rather than procedural control.

A: Option A keeps the dynamic viscosity form consistent and lands the x-location cleanly. Option B drops a zero by mixing ν and μ. Option C confuses transition behavior with the Reynolds calculation itself. Option D exaggerates viscosity effects by an order of magnitude.