Lessons from CST exercise

1
Problem Solving
An engineer wants to use a diesel engine to run a
pump that pumps 18,000 gallons of water per hour
into a tank that is 65 feet above the pump. How
big an engine should the engineer specify?
Engr 0012 (04-1) LecNotes 02-01
2
Solution Structure
solution to inclass lecture problem
determine power requirement (SI units) for
pump to lift 65,000 gal/h 65 ft your name
class info (Engr0012, Fall Term, ...) date
your e-mail address
conversion factors gal_to_m3
0.003785 m3/gal ... more conversion
factors)
parameters (constant, in SI units) g
9.8 m/s2 ... (any additional parmameters)
Engr 0012 (04-1) LecNotes 02-02
3
Solution Structure
knowns (in SI units) vol_per_s
65000gal_to_m3/h_to_s m/s2 ... (any
additional knowns)
supporting calculations equations (in SI
units) mass_per_s densityvol_per_s
kg/s ... (any additional equations)
ANSWER pump power requirement (in Watts)
pump_power force_per_sdistance W
Engr 0012 (04-1) LecNotes 02-03
4
Problem Solving
1. Clearly identify what will result if you are
successful
2. Identify a calculation route backward from
the end product to the knowns
3. Identify needed (constant) parameters
4. Identify needed conversion factors
5. Determine solution by working backward
4,3,2,1
Annotate your solution (use comments)
Engr 0012 (04-1) LecNotes 02-04
5
Class Activity
Workshop 02
Turn in diary file showing solution to Exercise 1.
Workshop 03
Turn in diary file showing solutions to Exercise
2a, b.
Engr 0012 (04-1) LecNotes 02-5