Modeling Of Mass Transport | Processes In Biologi...

Predicting how a drug spreads through a solid tumor. High interstitial fluid pressure in tumors often opposes inward convection, making diffusion the primary (and often slow) delivery method.

: Net rate of production or consumption (e.g., metabolic reaction). 2. The Mechanisms of Flux ( Nbold cap N Modeling of Mass Transport Processes in Biologi...

) because the path is obstructed by cells and extracellular matrix (ECM). Movement driven by fluid velocity ( ), like blood flow or interstitial fluid. Nconv=vCbold cap N sub c o n v end-sub equals bold v cap C 3. Key Applications Oxygen Delivery: Modeling how O2cap O sub 2 moves from capillaries into deep tissue. Since O2cap O sub 2 is consumed by mitochondria, is negative and usually follows Michaelis-Menten kinetics : Predicting how a drug spreads through a solid tumor

Modeling how solutes cross the lipid bilayer via passive diffusion or protein channels (Kedem-Katchalsky equations). 4. Dimensionless Numbers (The "Reality Check") To understand which process dominates, engineers use: Péclet Number ( ): Ratio of convection to diffusion ( , flow dominates (like in large arteries). , diffusion dominates (like in the brain parenchyma). Nconv=vCbold cap N sub c o n v end-sub equals bold v cap C 3

Ndiff=−D∇Cbold cap N sub d i f f end-sub equals negative cap D nabla cap C