Which of the following dimensionless numbers govern convective mass transfer from food surfaces to air?
Options:
(A) Sherwood number $Sh = \frac{k_c L}{D_{AB}}$ (ratio of convective mass transfer to molecular diffusion)
(B) Schmidt number $Sc = \frac{\mu}{\rho D_{AB}}$ (ratio of momentum diffusivity to mass diffusivity)
(C) Peclet number for mass transfer $Pe_m = Re \cdot Sc$
(D) Mach number representing sonic shock wave boundaries
Answer Key:
A, B, C
Step-by-Step Solution & Explanation
1. Sherwood number scales convective mass transfer (A).
2. Schmidt number governs boundary layer thickness ratios (B).
3. $Pe_m = Re \cdot Sc$ characterizes advective vs diffusive mass transport (C).
4. Food processing convective mass transfer occurs at low subsonic Mach numbers where compressibility shocks are irrelevant (D is false).