Introduction to Process Dynamics

Question 1

no build-up of conserved quantities in the system

Answer 1

STEADY STATE PROCESS

Question 2

study of the unsteady-state or transient process behavior

Answer 2

PROCESS DYNAMICS

Question 3

variables of interest that are
being measured or being
controlled

Answer 3

OUTPUT VARIABLES

Question 4

variables that are specified or manipulated before a
problem can be solved or a
process can be operated

Answer 4

INPUT VARIABLES

Question 5

output variables that arise naturally in the accumulation term of a dynamic material or energy balance

Answer 5

STATE VARIABLES

Question 6

fixed physical or chemical properties that are known (e.g. tank area, viscosity,
density, reaction rate constant, heat of reaction, activation energy, etc.)

Answer 6

PARAMETERS

Question 7

State variables are a function of time alone (ODEs)

Answer 7

Lumped

Question 8

State variables are a function of time and one or more spatial variables (PDEs)

Answer 8

Distributed

Question 9

Exhibit superposition; all variables and derivatives
have exponent 1

Answer 9

Linear

Question 10

If any one term is nonlinear, the model is
nonlinear

Answer 10

Non-linear

Question 11

Based on physical and chemical laws

Answer 11

First Principles

Question 12

Simpler models whose coefficients are fitted to
the actual process

Answer 12

Empirical

Question 13

Variables can assume any real value within an
interval

Answer 13

Continuous

Question 14

Variables can only take distinct values (integer,
binary, etc.)

Answer 14

Discrete

Question 15

In deviation form of dynamics models, dynamic behavior of resulting model is still the same, but shifted vertically so that the initial value starts at __

Answer 15

zero

Question 16

A series expansion of a function, f(x), about a fixed point, x=a. We will use the initial steady state value; a=x=x(0), as the fixed point.

Answer 16

Taylor series expansion

Question 17

Refers to the space whose axes are the state variables. The state of the system can be represented as a vector within that space.

Answer 17

State-space model

Question 18

Model that directly relate inputs (causes) to outputs (effects), but only one input-output pair at a time.

Answer 18

Transfer function