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by cpp_frog 1260 days ago
Can I ask you a couple of questions? I am in a patricular situation, I'm a mathematician who does FEM and I think my training has been too abstract. My most recent work involves programming custom code in C++ for the study of buckling of thin shells (finite element method, continuum mechanics, differential geometry of shells, and all under the umbrella of functional analysis). Still the region I live in has virtually no relevant positions for FEA, which prompts me to ask:

(1) I've been thinking of getting a certification in ANSYS or Abaqus (it's relatively cheap). Would it help if I get some certs, or would it be enough to have expertise in several open source finite element programs? - think deal.ii, PETSc, MFEM, MOOSE, FreeFEM, FEniCS and the like. I really like to use the latter because apart from being free, they give me more freedom and I can use them with parallel computing on UNIX machines.

(2) Regarding manufacturing and machines/machining, any book or resources that stood out? I'm most familiar with the Machinery's Handbook.

(3) For design, did you use a tablet? I've been looking into buying one and use it for design, preferably with FOSS. Any recs?

Thank you for your comments,

M.

4 comments

>Regarding manufacturing and machines/machining, any book or resources that stood out? I'm most familiar with the Machinery's Handbook.

I went to a top tier school for MechE and Materials, and would recommend two intro books: Engineering Mechanics Statics by Meriam and Kriage and Shigley's Mechanical engineering Design in that order . If you fully understand the contents of these book, it probably puts you in the top 10% of mechanical engineering graduates.

For a broader education, you can read Fundamentals of Heat and Mass transfer by Incropera, DeWitt, Bergmann & Lavine as well as Fundamentals of Fluid Mechanics by Munson, Young & Okiishi.

Understanding these two books will probably as well will probably put you in the top 1% of grads.

If you have a strong background in mathematics, these mostly deal with applications of linear algebra and differentials, so the value is understanding the applications.

From there, you can branch out. If applicable, Ogata's Modern Control Engineering and Tongu's Principles of vibration

Most undergraduates dont really understand these due to the heavy application of Laplace and Fourier transforms, but are relevant if you want to build complex machines.

Excellent overview. I'd also add "Marks' Standard Handbook for Mechanical Engineers" to the front of the list. Its a great way to dip your toe into the breadth of the field and will serve as a nice reference book on your shelf later if you keep going with it.
I started down the path to be a materials scientist and wound up in embedded hardware, so take my opinions with a big grain of salt.

For self-learning, I don't know if anyone would work through the problems in a statics textbook. Shigley looks good. Thanks for that recommendation.

For heat transfer, I eventually wound up on the bibliography from Hot Air Rises and Heat Sinks by Tony Kordyban, which is more focused on cooling electronics. I have Holman's Heat Transfer on my shelf as a result and I can recommend it for self-learning. One big advantage to Holman: he shows how to set up common thermal problems in Excel in an appendix. I would consider recommending a good continuum mechanics book in the place of a fluid mechanics book - I liked Yuan-Cheng Fung's First Course in Continuum Mechanics but I haven't looked at it or anything else in its domain for a while.

Ogata is a good controls text. I don't know if any of them are good for self-learning. I tried and had to take a class to wrap my head around feedback control. Tongue looks interesting. Thanks for the recommendation.

Kraige?
It is a really simple book and not particularly academic, but you have to start somewhere.

It is basically the equivalent of a picture book, with 200 pages of free body diagrams, which may be helpful to someone if they aren't used to thinking in terms of beams, forces, and moments.

The entire books' contents is probably covered in pages of Shigley's, and perhaps for some people that is enough..

I mean, you meant "Kraige" rather than "Kriage", right? I wasn't deprecating the book.
Ah yes, it was hard for me to tell the difference even reading the spellings side by side.

That said, it is definitely the weakest of the suggestions. The rest are serious books that a professional might refer back to. On the other hand you should really never need to refer back to a statics text, and it could be switched out for any number of options.

I really appreciate the recommendations. I have enough knowledge of the field to understand that control engineering and vibrational modes are extremely important but not enough to know what's most important to know about them or which books are more reliable or better written.

What do you think about Reuleaux's Kinematics of Machinery and the Machinery's Handbook?

If you can get access to student or lite versions of some FEA software, start using them. I've found few places have cared about my software certifications, and more than I can adjust to their software package of choice. Some places will have higher requirements, but not all.

Machinery handbook rocks, but it is far from perfect. It's great for machining, it doesn't cover all of mechanical engineering. I've leaned hard on Roarks formula handbook through my career. A materials reference book goes a long way too. More recently referring frequently to degarmos manufacturing book.

I've used a cheap-ish Windows laptop for almost all of my research and design. CAD can suffer as assemblies get large, I turn fancy rendering off as it is mechanical engineering, not making prettying renders. FEA can eat resources fast. I've pushed to a beefier desktop as required. I've done some CAD on a tablet, but I hate the form factor for it.

> Regarding manufacturing and machines/machining

There's an MIT course on OpenCourseware that's called (roughly) "How to make (almost) anything" and also "FUNdamentals of Machine Design." (or something like that!) I think they're by Richard (?) Slocum. I started a long time ago and cherry picked the parts I cared about. Slocum's writing is very entertaining and he's easy to follow along with.

As you can tell, my memory isn't that great :-)

For #2 check out the YouTube series "the secret life of components"