Modeling, Analysis & Monitoring
DERG & Bearfoil
Modeling & Analysis
Today, every unique component in a new aircraft engine is designed using a 3D modeling program. There are no longer masses of 2D blueprints produced (except for special requests). 3D programs such as Unigraphics or Catia are widely used in the aircraft business. Upon completion of the component being designed on the computer, the electronic files are saved and passed on for various purposes to various entities:
1. In-house analysis groups that determine the designed component's suitability in meeting the various parameters basic to the design, e.g. fatigue life, vibratory stress limits, temperature parameters, weight limitations, etc.
2. Suppliers that will produce the basic component, casting, forging, inspection gauging, etc., who in turn will forward the electronic data to their suppliers that build the tooling that will produce the component.
3. Manufacturing Centers that will machine the components where the electronic data is programmed into the units that will be used to machine, produce and inspect the final product.
So modeling is today's way of life and it has reduced the number of mistakes that were common in the past. It is not to say there are not pit-falls, there can be as Airbus found out on the A-380 program. In their case, although one common program (Catia) was used to design the electrical wirings system for different sections of the fuselage, two different version were used and when it came time to put the sections together, the electrical wiring didn't go together causing a ~2 year delay.
So if you model every component in a turbine engine, is it possible to assemble all the components together on the computer to see what the engine looks like in total? Why yes it is and it has been done. Then, is it possible to look at the engine on the computer and run it and perform dynamic analysis of vibrations, pressures, temperatures, transient conditions, clearance controls, SFC, etc? Well, yes but, some things have to be done first. Since many of the analysis programs were developed at different times, the codes used do not mesh together at all. So if the individual codes were to be redeveloped using a common code an actual engine can be put through its paces on the computer while checking key metrics and engine behavior characteristics. Mind you, this can be all accomplished without buying or producing any physical parts. This is the direction engine design and manufacturing is headed, if not already there at this moment.
Monitoring
Aircraft engine producers have known for sometime that the money (profit) is not in the sales of the original engine (often they are sold at cost or below cost early in the program), but in the subsequent sales of spare parts or replacement parts. Today it takes an investment of $2B to develop and certify a new large turbofan engine and it takes a long runway program to break even. In the meantime, airlines worldwide struggle to make money with the ups and downs of fuel costs and revenue passengers in ever changing economic times. To cut costs, many have disbanded their engine overhaul shops and therein lies a new business for the OEM's, provide this service. To do it right, real time engine monitoring is a necessity to set realistic fees to provide this service (Power by The Hour, Total Care, whatever). And so you will see increasing levels of realtime downloading of engine operating parameters (as many as a hundred or more parameters) to both the airline and OEM's appraised of operating conditions while working together to keeps the engines performing and in the air, out of the overhaul shops as much as possible, a win-win situation for everyone.
This is how I see the engine business going forward in today's computer driven world.