Engineering Analysis http://edugen.wiley.com/edugen/courses/crs2436/crowe9771/crowe9771...
1.5 Engineering Analysis
In fluid mechanics, many problems are messy and open-ended. Thus, this section presents a structured approach
to problem solving.
Engineering analysis is a process for idealizing or representing real-world situations using mathematics and
scientific principles and then using calculations to extract useful information. For example, engineering analysis
is used to find the power required by a pump, wind force acting on a building, and pipe diameter for a given
application. Engineering analysis involves subdividing or organizing a problem into logical parts as described in
Table 1.4. Notice that the columns describe what to do, the rationale for this step, and typical actions taken
during this step. The approach shown in Table 1.4 is used in example problems throughout this text.
Table 1.4 STRUCTURED APPROACH FOR E GI EERI G A ALYSIS
What To Do Why Do This? Typical Actions
Problem Definition: This
· To visualize the situation · Read and interpret the
involves figuring out what the
(present state). problem statement.
problem is, what is involved,
and what the end state (i.e., goal
· To visualize the goal (end · Look up and learn
state is.
state). unfamiliar knowledge.
· Document your
Problem definition is done
interpretation of the
before trying to solve the
situation.
problem.
· Interpret and document
problem goals.
· Make an engineering
sketch.
· Document main
assumptions.
· Look up fluid properties;
document sources.
Plan: This involves figuring
· To find an easy way to · Generate multiple ideas
out a solution path or  how to
solve the problem. for solving the problem
solve the problem.
· Saves you time. · Identify useful equations
Planning is done prior to
from Table F.2.
jumping into action.
· Inventory past solutions.
· Analyze equations using a
term-by-term approach.
· Balancing number of
equations with number of
unknowns.
· Make a step-by-step plan.
Solution: This involves solving
· To reach the problem goal · Use computer programs.
the problem by executing the
state.
plan.
· Perform calculations.
· Double-check work.
· Carry and cancel units.
1 of 2 1/15/2009 12:05 AM
Engineering Analysis http://edugen.wiley.com/edugen/courses/crs2436/crowe9771/crowe9771...
What To Do Why Do This? Typical Actions
Review: This involves
· Gain confidence that your · Check the units of answer.
validating the solution,
answer can be trusted.
exploring implications of the
· Check that problem goals
solution, and looking back to
· Increases your have been reached.
learn from the experience you
understanding.
· Validate the answer with a
just had.
· Gain ideas for simpler estimate.
applications.
· Write down knowledge
· To learn. that you want to
remember.
· List  what worked and
 ideas for improvement.
Copyright © 2009 John Wiley & Sons, Inc. All rights reserved.
2 of 2 1/15/2009 12:05 AM