1. Introduction to Engineering Calculations
Chapter 1
Introduction to Engineering Calculations

2. What’s in this chapter? Bioprocess Engineering Profession
Units and Dimension
Conversions of Unit
Systems of Units
Force, Weight and Mass

3. Introduction
Describe the basic techniques for the handling of units and dimensions in calculations.
Describe the basic techniques for expressing the values of process variables and for setting up and solving equations that relate these variables.
Develop an ability to analyze and work engineering problems by practice.

4. Bioprocess Engineering Profession
BIOCHEMIST VS
BIOPROCESS ENGINEER

5. Role of Bioprocess Engineering
exploit advances in biology to create new products
design biochemical processes & operate plants
develop energy resources,
protect the environment.
Develop new, environmentally benign, and safer processes to make the biochemical products that people depend on.
Work in research and development laboratories, creating polymeric materials with improved performance and durability.
Work in manufacturing, making vaccines and antibiotics.
Invent new ways to keep our food and water supplies safe.

6. CHEMICAL PROCESS RAW MATERIALS INTERMEDIATE PRODUCT REACTION PROCESS
SEPARATION PROCESS
REACTION PROCESS
RAW MATERIALS
INTERMEDIATE PRODUCT
FINAL PRODUCT

7. Bioprocess Engineer’s Task
You need to:
Minimize production of unwanted byproducts
Separate the good (product) from the bad (byproducts)
Recover the unused reactants
Maximize profit, minimize energy consumption, minimize impact on the environment

8. OPPORTUNITIES FOR BIOPROCESS ENGINEERS
pharmaceuticals
polymers
energy
food
consumer products
biotechnology
electronic and optical materials.

9. Units and Dimensions Objectives:
Convert one set of units in a function or equation into another equivalent set for mass, length, area, volume, time, energy and force
Specify the basic and derived units in the SI and American engineering system for mass, length, volume, density, time, and their equivalence.
Explain the difference between weight and mass
Apply the concepts of dimensional consistency to determine the units of any term in a function

10. Units and Dimensions Dimensions are:
properties that can be measured such as length, time, mass, temperature,
properties that can be calculated by multiplying or dividing other dimensions, such as velocity (length/time), volume, density
Units are used for expressing the dimensions such as feet or meter for length, hours/seconds for time.
Every valid equation must be dimensionally homogeneous: that is, all additive terms on both sides of the equation must have the same unit

11. Conversion of Units 36 mg 1 g = 0.036 g 1000 mg
A measured quantity can be expressed in terms of any units having the appropriate dimension
To convert a quantity expressed in terms of one unit to equivalent in terms of another unit, multiply the given quantity by the conversion factor
Conversion factor – a ratio of equivalent values of a quantity expressed in different units
Let’s say to convert 36 mg to gram
36 mg
1 g =
0.036 g
1000 mg
Conversion factor

12. Dimensional Equation Write the given quantity and units on the left
Write the units of conversion factors that cancel the old unit and replace them with the desired unit
Fill the value of the conversion factors
Carry out the arithmetic value

13. Dimensional Equation Convert 1 cm/s2 to km/yr2 1 cm s2 h2 day2 m km
(3600 x 24 x 365) 2 km =
9.95 x 109 km/ yr 2
100 x 1000
yr2

14. Systems of Units Components of a system of units:
Base units - units for the dimensions of mass, length, time, temperature, electrical current, and light intensity.
Multiple units- multiple or fractions of base unit
E.g.: for time can be hours, millisecond, year, etc.
Derived units - units that are obtained in one or two ways;
By multiplying and dividing base units; also referred to as compound units
Example: ft/min (velocity), cm2(area), kg.m/s2 (force)
As defined equivalent of compound unit (Newton = 1 kg.m/s2)

15. Systems of Units 3 systems of unit: a) SI system
b) American engineering system
c) CGS system

16. Base Units Base Units Quantity SI Symbol American CGS Length meter m
foot ft
centimeter cm
Mass
kilogram kg
pound mass
lbm
gram g
Moles
gram-mole
mole
pound mole
lbmole
Time
second s
Temperature
Kelvin K
Rankine R

17. Multiple Unit Preferences
Multiple SI Units
Multiple Unit Preferences
tera (T) =
10 12
centi (c) =
10 -2
giga (G) =
10 9
milli (m) =
10 -3
mega (M) =
10 6
micro (μ) =
10 -6
kilo (k) =
10 3
nano (n) =
10 -9

18. Derivatives SI Units Derived SI Units Quantity Unit Symbol
Equivalent to the Base Unit
Volume
Liter L
0.001m3 = 1000 cm3
Force
Newton (SI)
Dyne (CGS) N
1 kg.m/s2
1 g.cm/s2
Pressure
Pascal Pa
1 N/m2
Energy/ Work
Joule
Calorie J
cal
1 N.m = 1 kg.m2/s2
4.184 J =4.184 kg.m2/2
Power
Watt W
1 J/s = 1 kg.m2/s3

19. Force and Weight
Force is proportional to product of mass and acceleration
Usually defined using derived units ;
1 Newton (N) = 1 kg.m/s2
1 dyne = 1 g.cm/s2
1 Ibf = Ibm.ft/s2
Weight of an object is force exerted on the object by gravitational attraction of the earth i.e. force of gravity, g.
Value of gravitational acceleration:
g = m/s2
= cm/s2
= ft/s2

20. Force and Weight
gc is used to denote the conversion factor from a natural force unit to a derived force unit. gc =
1 kg.m/s2
lbm.ft/s2 1N
1 lbf

21. ANY QUESTION?