SpinOffs

In my last blog I wrote about visiting a local middle school to give a talk on ‘What is Turbomachinery, and How Does It Work?’   The quiz at the end of the talk was for the students to list all the turbomachinery in their home. I had a few examples in mind to get the list started but was impressed with how long of a list we were able to generate after the students thought about it for a while. Since then the list has grown to include 40 items.   I will present those 40 below, but first let me repeat the assignment and the ground rules to see if you can think of more:

1. List every piece of turbomachinery in your home.
2. Inside and outside (in your yard is OK).
3. Positive displacement equipment is OK to list.
4. Don’t include turbomachinery in your cars or any vehicle or wheeled yard equipment (that’s another list…)

On occasion I’m invited to a local middle school to give a talk to one of the science classes about ‘What Is Turbomachinery, and How Does It Work?’.   I teach in several of the turbomachinery design courses we give at Concepts NREC, and while I’m comfortable in those courses, presenting at this level was different. I originally found it a challenge to come up with a good presentation that would keep the students' attention, while still providing some science education as requested by the science teacher that invited me. Derivation of the Euler turbomachinery equation was probably out. The attention getters that seemed to work best to get the conversation going included bringing our turbocharger cut-away (definitely the biggest hit of anything I brought), along with other interesting impeller samples. From there getting into the purpose of various types of turbomachinery (compressor vs turbine vs pump) and a very high level discussion of energy transfer to/from a fluid, seemed to flow. Getting them thinking about some of the physical aspects of turbomachinery operation (Just how fast is 100,000 rpm?) also seemed to keep their attention.

If there’s one thing good about sitting in snarled traffic in Boston, it’s that you get to see some very original bumper stickers. The most recent bumper sticker I saw was probably the strangest one, no doubt created by some engineering professor who doesn’t see that the glass is half full, but that it has a safety factor of 2! Nevertheless, the bumper sticker stated the obvious when one thinks about it: ENTROPY HAPPENS! And then, to emphasize the point, the artist has the letters slowly “evaporating,” demonstrating graphically that entropy proceeds from order to chaos.

I recently got back from my favorite annual conference: ASME’s Turbo Expo. This year, someone thought it would be a good idea to hold it in Phoenix, Arizona…in the summertime.  While that’s not the choice I would have made, I did enjoy the conference very much and thought it was well worth attending. 

When discussing the efficiency of transforming one form of energy to another, circularity is the way to go. Anyone who has spent even a little time studying engineering thermodynamics knows that the continuous transformation of energy from a heat energy source to produce mechanical or electrical power must contend with components that operate in a cycle. The key word here being “continuous”. The combustion of any carbon-hydrogen bond material (i.e., fossil fuels), or the liberation of heat energy from any number of materials when placed in a piston-cylinder, would not be very useful if the piston is not returned to its initial “precombustion” position. It is literally the difference between the one-time launching of an object from the cylinder or the continuous production of rotary shaft power; power that can be used to propel a vehicle forward or turn an electric generator. It is the cyclic operation of the fluid in the thermodynamic cycle that enables heat engines and refrigeration cycles to provide continuous power, or cooling, that is needed for the safety, security, comfort and all the other “hierarchy of needs” that was so well formulated by the renowned humanist psychologist, Dr. Abraham Maslow.

Wow, Concepts NREC had a lot going on at this year's ASME Turbo Expo 2019 in Phoenix, AZ! We held our North American CAE User Group Meeting, spoke to over 200 people at our booth, chaired several sessions and presented two papers. In case you were not able to go, here are the abstracts from the two papers:

Summer is almost here, at least in my hemisphere, so here are some of the best places around the world people in the turbomachinery industry might find interesting! Know of another? Share your favorite!

In this blog series, I covered a lot of thermo-fluid options in engineering analysis, from the simplest perfect gas (When Perfect is Good Enough – Perfect Gas Models) and ideal liquid, (Fluid Modeling: Liquified ) to much more complex approaches (Going Through a Phase – Modeling Phase Change with Cubics) and (Getting Real – Advanced Real Gas Models). In this blog, I’ll cover the ultimate in thermo-fluid modeling: non-equilibrium modeling. It's rare and expensive, sort of like the Schorschbrau’s Schorschbock 57, a beer that sells for $275/bottle.

The great engineer, Dr. Nikola Tesla, is best known for his work with alternating current (AC) electricity, but, did you know that he patented a bladeless type of turbomachinery in 1913? Called the Tesla Turbine, he developed it while trying to make an engine that was light enough to power his ultimate goal of building a “flying machine”. Tesla-type turbines can also be referred to as multiple-disk, friction, shear-force, or boundary layer turbomachinery.

When fluids undergo a phase change (see Phase Change - Make Mine a Double), it typically has a very significant effect of the flow behavior and energy level of the system.  Some examples of this are: cavitation in a pump, condensing near the exit of a steam turbine, even the everyday phenomenon of the weather is basically a never-ending phase change process of water, and its interaction with air.