Tuesday, September 18, 2007

New engine cycle is 60% efficient

Analysis of a new engine design is complete! Here are some facts about it:


1. Utilizes a new thermodynamic cycle

2. Will run on most fuels interchangeably with very low emissions

3. Initial design is a compact engine, 130 hp

4. Over 60% efficient over most of its operating range

5. Which means it can help to stop global warming!


We are now looking at ways to fund construction of the small prototype engine. Any suggestions or offers of assistance are welcome. I may be reached at Ernsdesk@aol.com


The engine design is built around a new "thermodynamic cycle." This is a simplified model of how the engine works, which ignores all the messy details of a real engine such as friction, heat loss, and inertia. The cycle is described as a sequence of operations on a captive ideal gas. The new engine cycle is a combination of two old cycles, the Atkinson (or Miller) cycle and the Diesel cycle: the Atkinson-Diesel cycle.

Oh, no, you can't use this ideal cycle formula to design the exact engine and determine its efficiency, but it gives direction to the analysis. A separate program is used for the actual engine design.

I wanted to post the complete description of the cycle and derivation of the cycle efficiency here, but the equations didn't come over in the document. Send me an email if you would like a copy of the complete Atkinson-Diesel cycle description.

Thursday, April 21, 2005

LATEST MILEAGE NEWS

LATEST MILEAGE NEWS

Mileage of the Beetle and drag reducer have been significantly increased by lowering rolling resistance of the car's tires. Currently, mileage is close to 65 miles per gallon at 65 miles per hour.

This car is now about as good as it gets. Further steps available to reach even higher fuel economy are:

1. Adding an electric drive (e.g., hybrid conversion)
2. Redesign the car body for lowest drag
3. Incorporate an improved engine.

I am beginning to work on all of these. These steps are much harder than the past modifications to the Beetle. I hope to be able to report on progress later this year.

Ernie Rogers

Monday, November 8, 2004

CAN WE BUILD MORE EFFICIENT ENGINES?

Stop global warming


Yes, I think we can. The present internal combustion engine was mostly developed in a time when fuel cost and efficiency were not imperatives. We need to go back to the early days of engine devleopment and reassess the way designers handled branches in the design road. We may have overlooked some better choices way back when the discovery of oil in Oklahoma and Texas seemed to say that there would be cheap gasoline forever.

One of these early branches in the road was a choice between four-stroke cycle engines and two-stroke cycle engines for automobiles. At the time, we used carburetors to feed fuel to the cylinders. In this context, the four-stroke engine is a far better choice. (More efficient and less polluting.)

But, the trend today is toward injection of fuel directly into the cylinders. With this modern option, the two-stroke cycle actually provides a far more efficient engine. Here are some other choices that need to be reviewed:

1. Engines are only designed for either gasoline or diesel, and nothing else.
2. Compression ratios are lower than one would choose for best efficiency.
3. Engine design principles are not based on a need to reduce weight.

Some people are looking at the exciting possibilities still left to be explored. A possible outcome may be radically new engine types in the near future.

Ernie Rogers