part ii process dynamics. process model types 1.mathematical model 2.fundamental and empirical...
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Part II Process Dynamics
Process model types
1. Mathematical model
2. Fundamental and empirical model
3. Steady-state and dynamic model
4. Lumped (ODE) and distributed (PDE) model
Chapter 3 Modelling principles
Example 3.1
(1) Overall material balance
(2) Component material balance
(3) Energy balance
Example 3.2 Isothermal CSTR
Example 3.3 Two isothermal CSTR
※ Linearization
Which is used to approximate the nonlinear system with linear differential equations.
(1) Enthalpy H
(2) Equilibrium vapor mole fraction y
(3) Reaction rate
Linear approximation
* Linearization for one variable
Ex. 3.4 linearization of Arrhenius equation
Sol.:
* Linearization for more variables
Ex. 3.5 Linear approximation of density of an ideal gas
Sol.:
* Linearization for differential equations
S1. The first-order differential eqn
S2. The steady state values as initials
S3. Linearization
Ex. 3.6 A differential eqn. from a CSTR system
Where
Find the time constant and gains of transfer function of CA.
S1. Linear approximation
where CA, F, CAi, are derivative variables, and
S2. Standard form
where
Ex. 3.7 Linearization of an isothermal CSTR
To determine steady state values
The derivation variable is introduced as
(S1) The standard form is arranged as
(S2) Dynamic responses
Ex. 3.8 (Complex) nonisothermal CSTR
Homework#1 Simulation of CSTR system (limited to up 20 reports) (see, appendix C)
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