Did you come up with a better reply to that interview question? In case you missed last week's blog, the question posed was about a bracket on an engine that was cracking from fatigue. How would you solve the problem?
First of all, you should verify that it is indeed fatigue that is causing the problem. Examining the surface of the crack will tell you that quickly. Consulting references for the particular material will usually include pictures of various types of fractures. Once you’ve verified the cause, that same reference will also give you the stress level at which cyclical fatigue will be experienced. Knowing the stress level, one can then back calculate the Moment of Inertia of the failed section that will reduce the stress to a lower level. There are, of course, other approaches as well, such as reducing the level of the applied stress. The key is to start with an analysis that brings you to a logical solution. The old “hack-and-whack” approach to problem solving is far too expensive in today’s world. You do not want those kinds of engineers on your staff.
In the industrial heating business, heat implies the concept of enthalpy. Remember that from your old thermo courses? Well, you might be surprised at how many engineers in this business can’t explain that concept. I’ve used that question many times during interviews with job applicants. Even some new graduates have forgotten what it means.
The very words “industrial heating” imply the fundamental concept of heat transfer. Obviously, to heat one substance means transferring heat to that substance from another source. You can’t get very far in understanding heat transfer if you’ve forgotten about enthalpy.
Heat transfer itself can involve very many difficult calculations. The formulae can be very complicated, and since it implies by its very nature a transient state, differential calculus is involved if you need an exact solution. But rarely do we need an exact solution to that degree in our day-to-day problem solving. So how do we get answers?
Next week I’ll discuss concepts that I learned from some much-esteemed professors in this field that you can apply to your work as a manager.