Mass and Heat Transfer in Pharmaceutical Processes

The movement of molecules of one substance through another, driven by concentration differences.

The process of converting a liquid into a vapor by heating it, separating components based on their boiling points.

The process of dissolving a solid substance into a liquid solvent, driven by concentration gradients.

The process of removing liquid from a solid material by evaporation, typically via heat application.

The formation of solid crystals from a solution, often driven by changes in temperature or concentration.

The movement of molecules due to their random thermal motion, occurring at the microscopic level.

The movement of molecules due to large-scale fluid motion, causing mixing and faster mass transfer.

The driving force behind mass transfer, encouraging molecules to move from areas of high concentration to low concentration.

A mathematical relationship describing the rate of diffusion through a stationary medium.

The process by which molecules move from one phase to another (e.g., gas to liquid) across a defined boundary.

A process that separates components of a liquid mixture by their different boiling points. More volatile components move into the vapor phase, while less volatile components remain in the liquid phase.

The process where molecules move from a solid phase into a liquid phase, dissolving the solid.

The process of removing moisture from a solid material. Water molecules move from the solid to the drying air or gas.

The formation of solid crystals from a liquid phase. Molecules move from the liquid to the solid phase, forming crystals.

A type of fluid flow where the fluid moves in smooth, parallel layers.

A mechanism of mass transfer driven by the random motion of individual molecules in a laminar fluid.

A chaotic fluid flow with swirling eddies and mixing.

Mass transfer driven by the movement of groups of molecules within swirling eddies of a turbulent fluid.

The difference in concentration of a substance between two locations.

Movement of a substance from an area of high concentration to an area of low concentration.

The rate of change of concentration with respect to distance.

Heat transfer that occurs due to the direct contact of two objects at different temperatures. Heat flows from the hotter object to the cooler one.

Heat transfer through the movement of fluids (liquids or gases). It occurs due to differences in temperature and density within the fluid.

Heat transfer that occurs through electromagnetic radiation. It does not require a medium and can occur in a vacuum.

The rate of heat transfer, often represented by Q, is directly proportional to the heat transfer coefficient (h or U), the surface area (A), and the temperature difference (delta T).

This type of heat transfer is of lesser interest in pharmaceutical processes, as it is less relevant compared to conduction and convection.

The transfer of heat energy through direct contact between molecules, where heat flows from a region of higher temperature to a region of lower temperature.

The state of a material where the temperature gradient across it remains constant over time, meaning the rate of heat flow is stable.

The rate at which heat energy flows through a material, measured in Watts (W).

The difference in temperature between two points in a material, indicating the direction of heat flow.

The measure of a material's ability to conduct heat, indicating how easily heat flows through it.

The process where heat transfer across a boundary between a fluid and a solid surface occurs primarily through conduction.

The rate at which heat is transferred through a material. Measured in Watts or joules per second.

The opposition to heat flow. A high thermal resistance means heat flows slowly, a low thermal resistance means heat flows easily. Calculated as (x/k).

A material that reduces heat flow. It has high thermal resistance and low thermal conductivity.

The change in temperature over a specific distance.

A mathematical equation that describes heat flow through a material. It relates heat flow rate to thermal conductivity, area, and temperature gradient.

A thin slice of material used to simplify the calculation of heat flow. The equation used for the thin slab is simpler and more accurate in some cases.