Fluid Mechanics
A modern course
Preface
These are my notes dating back more than 20 years. Lucky I check-pointed each version so I could map my progress. This is one of the earlest check-pointed versions. I will expand the checkpointed versions over time with the anticipated completion data of May 2027. Unfortunatly, my versions are in LaTeX and the final version will be in Quarto. But, good news, with a bit of time, LaTeX can be ported over to Quarto!!
Preface
Why Another Fluid Mechanics Book?
Why write another fluid mechanics textbook?
There are already many good books on the subject, and we are entering an age in which artificial intelligence can explain concepts, solve equations, write code, and increasingly perform tasks that once required years of specialized training.
At first glance, this might seem like exactly the wrong time to write another textbook.
I believe it is exactly the right time.
Engineering education will have to adapt to AI. Universities will have to adapt. Faculty will have to adapt. Homework, examinations, software, and the way we determine whether a student actually understands engineering will have to adapt as well.
Having spent more than twenty years as a professor, I have also seen how difficult adaptation can be. Faculty are often expected to respond to enormous changes while working within systems filled with rules, heavy teaching loads, limited resources, and administrative decisions over which they have little control.
This book is my attempt to try something different.
The fluid mechanics itself should look familiar. Conservation of mass is still conservation of mass. Bernoulli’s equation has not changed, nor have the Navier-Stokes equations disappeared.
What I hope will be different is the way this book exists.
A Living Textbook
I intend this to be a living book.
Software provides a useful analogy. Software has versions, releases, corrections, new features, and occasionally ideas that are replaced by better ones.
Why shouldn’t a modern engineering textbook work the same way?
This book will have documented versions. Some changes may simply correct an equation or improve a figure. Others may add chapters, computational methods, homework problems, or entirely new approaches to teaching a subject.
An instructor should also be free to remain with an older version if that version works better for a particular course.
The basic idea is:
The book should adapt to engineering education rather than forcing engineering education to adapt to the book.
A Community Book
I am beginning this project as its author, but I do not intend for it to remain exclusively mine.
At present, I own the copyright to the book, but my intention is to change that structure over time so that additional authors can formally join the project and receive appropriate recognition for their contributions.
Authorship should evolve as the book evolves.
If another professor develops a better explanation, adds an important chapter, contributes a substantial collection of problems, or becomes one of the primary people maintaining the book, that contribution should be recognized.
Eventually, someone else’s name may quite properly appear before mine.
That does not bother me. In fact, it is part of the objective.
I would like the book eventually to exist independently of its original author.
One possible way of accomplishing this is to maintain the textbook project through a platform such as GitHub. The source files, figures, computer code, corrections, and revisions could be managed much like an open-source software project.
That also introduces an interesting possibility: forks of the textbook.
An instructor or group of instructors might decide that they want a different version of the book. They could potentially fork the project and develop their own branch while improvements from those branches could, when appropriate, be contributed back to the main textbook.
We could ultimately have an introductory version, an advanced version, or versions emphasizing civil, mechanical, environmental, or other areas of engineering.
That is what I mean by a living book.
Why Textbooks Must Change
One thing that has always interested me is how slowly engineering textbooks sometimes evolve.
I can open textbooks today and find problems remarkably similar to the ones I encountered as a student decades ago. The artwork is better, the printing is better, and the pages may now be in color, but the underlying problems often remain essentially the same.
Has engineering changed so little since the 1970s and 1980s?
Clearly not.
Computers have changed. Instrumentation has changed. Numerical methods have changed. Engineering software has changed. The workplace has changed. And now artificial intelligence is changing how information is obtained and used.
Yet our educational materials sometimes continue as though none of this has happened.
There is a phrase that can be dangerous to any institution:
“That’s the way we’ve always done it.”
Systems that stop adapting eventually become vulnerable to systems that do.
The Homework Problem
Artificial intelligence makes adaptation especially important when we consider homework.
A traditional textbook contains a finite collection of problems. Those problems may remain in circulation for decades, their solutions are widely available, and today they can often be submitted directly to AI systems.
I do not believe the answer is to pretend AI does not exist.
Instead, we have to keep moving.
The system supporting this book will allow participating instructors to contribute new homework problems to a shared collection.
An instructor might use established problems, contribute original ones, modify existing problems, develop parameterized versions, or create entirely new assignments.
A static collection of problems eventually becomes familiar.
A community continually creating and improving problems is much more difficult to become static.
This will not “solve” the AI problem.
But it represents adaptation rather than surrender.
More Than a Printed Book
The printed textbook is only one part of the project.
The book itself will also be available online, along with supporting materials such as:
- homework problems,
- quizzes and examinations,
- computational examples,
- instructor resources, and
- additional or advanced material.
For the learning-management portion of the project, I plan to use Moodle. I have more than twenty years of experience installing, operating, and administering Moodle systems.
The underlying infrastructure can use technologies such as Proxmox and containers, making it possible for different instructors to operate separate courses with their own schedules, assignments, and students while sharing the same general infrastructure.
The objective is to make the textbook part of an adaptable educational system rather than simply a PDF placed on a website.
Keeping the Cost Low
Affordability is another major goal.
Engineering textbooks commonly cost $150, $200, or more. I would like this project to follow a different model.
The printed book can be self-published at a relatively low cost, while the book itself can also be made publicly available online.
Operating the educational infrastructure, however, is not free. Servers, storage, backups, bandwidth, and maintenance all have costs.
My current expectation is that access to the hosted course system might require a modest fee, perhaps around $30 to $50 per student, primarily to keep the infrastructure operating. That amount will necessarily change as technology and operating costs change.
The goal is sustainability, not maximizing the price of the textbook.
An Invitation
You do not have to contribute to this project to use the book.
You can simply teach from it.
But I hope some instructors will choose to participate.
You might contribute a homework problem, correct an error, improve a figure, rewrite an explanation, add a computational example, develop an entirely new section, or eventually become one of the authors maintaining the project.
Over time, I hope the textbook can be managed by a community, perhaps ultimately through a nonprofit or similar organization whose purpose is simply to keep the project alive and evolving.
I do not know exactly what form all of this will eventually take.
That is part of the experiment.
Artificial intelligence is going to change education. Exactly how much it will change it, none of us yet knows.
But standing still is not a strategy.
We have to experiment, build, test ideas, keep the ones that work, and replace the ones that do not.
Engineering itself works that way.
Perhaps engineering education should too.
My hope is that this becomes more than a book I wrote.
I hope it eventually becomes a book that belongs to the people who teach from it, learn from it, improve it, fork it, and carry it forward.
A living textbook that can continue to evolve long after I am gone.