Differential Balance Equations (DBE)

Differential Balance Equations

Differential balances, although more complex to solve, can yield a tremendous wealth of information about ChE processes. General balance equations for each of the modes of transport can easily be derived either directly from shell balances or via control volume analysis. Understanding the origin and meaning of the terms that make up these balance equations lies at the heart of posing and solving complex transport problems.

• Describe the physical meaning of each of the terms within a general thermal energy balance
• Simplify the general thermal energy balance equation (identifying assumptions)
• Identify reasonable boundary conditions in a conduction problem (explain when each is most useful)
• Describe the physical meaning of each of the terms within a differential mass balance equation
• Simplify the mass balance equation (identifying assumptions)
• Identify reasonable boundary conditions in a mass transport problem (explain when each is most useful)
• Describe the physical meaning of each of the terms within the momentum balance
• Explain the physical meaning of the terms in the differential Continuity and Navier-Stokes Equations
• Simplify both the differential Continuity and Navier-Stokes Equations
• Identify proper boundary conditions for use with the Navier-Stokes equations