Thursday, January 17, 2008

It is always the oil system


The above picture was taken after scattering an RB26DETT engine at Laguna Seca Raceway. An RB26 is an inline 6 engine. That means the oil pan and crank shaft are both fairly long. It also means that if you pull too many g's in a corner the oil has plenty of space to go to avoid the pickup. No mater what little tricks are done, like swinging oil pickups, there are situations when the car can pull too many g's for it to matter. The only solution then is to install a dry sump oiling system. Laguna Seca caused a giant hole in the RB26 engine block because it has a set of corners known as the corkscrew. The corkscrew combines steep elevation change along with tight cornering. That means the oil sloshes away from the pickup, thus drying up the bearings, causing at least one to seize and sending the piston and rod out the side of the motor.

When it comes to the lifespan of engines and turbochargers the oiling system is the most important thing. The majority of failures are due to some problem with oil. When you have many rotating parts lubrication is key. I have now learned that even with a shift to electric motors it does not change. Electric motors have losses, those losses come in the form of heat. Therefore the motor still needs to be cooled and it gets cooled with oil. Any issue with the oil system means, motor failure. Pressure must be monitored, or seals could blow. Temperature must be monitored or tolerances will expand beyond spec. Debris must be filtered or lines will clog and metallic flakes will get attracted by the motor's electric field.

Yesterday I started a new job. I am working at General Motors Advanced Technology Center in Torrance, CA. My titles is Mechanical Motor Design Engineer. There is a lot to learn, but it is all very interesting. I am spending a lot of time lately in the motor lab. That is about as detailed as I will get on anything though. I work on the future for the most part and the future is a secret.

1 comment:

Pam Hoffman said...

Congratulations on the new job!

Your post makes me think of something used in rocket motors. As you can imagine, they are subjected to many different and high forces and gravities.

In the out-flow from the tanks to the engines, there is a device meant to help with the liquids vortexing and creating a hole in the fuel or the oxidizer (in bi-propellent systems) as it swirls down.

If you don't add in this little device (i forget what it's called at the moment) you can put a rocket in the drink. Just ask Elon Musk about his last launch...

I wonder if something similar would help with this issue.

I'd probably have to sit down with you and draw some pictures...

BTW, I used to live in Torrance and my daughter went to High School at South High. I'm in Laguna Niguel currently.

Good Luck with the new job!

Pam Hoffman
http://seminarlist.blogspot.com