Scuderi Group Air-Hybrid Engine claimed to double fuel efficiency

I hope they show it actually running on fuel. Air proves nothing other than it is mechanically feasible.

Here's a quote, where Sal Scuderi responds to some questions.

--- quote --- There has been a significant amount of questions recently regarding the Scuderi Engine, especially in light of the funding approved by the federal government for its development. As president of the Scuderi Group and one of the inventors of the engine, I thought it might be helpful to try to clear-up some of the basic misconceptions about the engine.

The Scuderi Engine does take advantage of the Miller Effect but not in the method used by conventional engines. The Miller Effect in the Scuderi Engine is achieved by having a longer stroke on the power cylinder verses the compression cylinder - not by leaving the intake valve open and supercharging the intake. However, this is only one feature of the Scuderi Engine that helps to improve efficiency. From a thermodynamic prospective the objective for increasing engine efficiency is to somehow increase the area under the pressure volume (PV) curve of the Otto Cycle. In the Scuderi Engine, the PV diagram is really two separate curves - one for compression and one for combustion. It is the difference in the areas under the curves that determines the efficiency of the engine.

There have been split-cycle engines in the past. However, they have never functioned as well as conventional Otto cycle engines for two main reasons. First, their volumetric efficiency (how well air is pumped through the engine) was never as good as a conventional design. This caused the split-cycle engines to be larger resulting in a lower power density and greater frictional losses especially on part load. Second, compressing the gas in the compression cylinder and again in the power cylinder (because they fired before top dead center) was doing work on the gas twice. Consequently, they were never as efficient as a conventional engine. However, if you could solve these problems, the advantage of the split configuration is that it really is two systems in one - a compressor and an engine. This gives you a great deal of design flexibility.

The Scuderi Engine solves both problems by using some unique valve designs and by firing after top dead center (ATC). It was the firing ATC that was really the major hurtle that had to be overcome. Normally firing ATC is considered bad practice in engine design; it causes reductions in both power and efficiency. In the Scuderi Engine, the combustion process begins with high pressure air entering the power cylinder from the crossover passage. Massive turbulence is generated in the cylinder causing very rapid atomization of the fuel-air mixture. The result is a flame speed, or rate of combustion, that is twice as fast as anything previously obtainable. Because of the rapid rate of combustion, high pressures on the power piston are achieved even though the piston is pulling away from the firing point. The effect is a split configuration with actually higher efficiency and more power density than a conventional engine. (The firing point for the Scuderi Engine is between 10 and 15 degrees ATC.)

An interesting phenomenon that resulted from firing after top dead center was reduced peak temperatures. Our power cylinder does have higher average temperatures than a conventional system; however, its peak temperatures are considerably lower. It is the peak temperatures of combustion that generate the NOx emissions. Because Scuderi Engine?s peak temperatures are significantly lower, the amount of NOx produced is up to 80% less than a conventional engine.

Because of its design flexibility, the Scuderi Engine makes it possible to enhance efficiency and performance in ways that are difficult, if not impossible, in a conventional design. The Miller Effect, for example, can easily be achieved by increasing the length of the power cylinder. Simply increasing the diameter of the compression cylinder can supercharge the engine without any added equipment or complexity. (A four-cylinder engine could give you the power of a six-cylinder engine but have approximately the size, weight and cost of a four cylinder.)

However, one of the most amazing features of the Scuderi Engine is that it really is two systems in one - an air compressor on one side and a combustion engine on the other. By having fuel only enter the engine at the power cylinder through direct cylinder injection, the compression cylinder is pumping only air. This makes the Scuderi Engine the ideal engine for an air-hybrid system. This feature of the engine has only recently been patented and is expected to have a huge impact on the market.

By simply adding a storage tank and some controls, the engine would have the ability to store energy normally lost during braking. (Similar to the current electric hybrids) The big difference is that the Scuderi Air-Hybrid only requires one system, not two. Since the Scuderi Engine already uses compressed air in its combustion process, it can utilize the energy stored in the tank without modifying how it operates. The gains in efficiency come from eliminating the need for a compression cycle. When the engine is operating out of the storage tank that has been pressurized from the braking of the vehicle, the efficiency of the engine can potentially run over 80%. Gains in mileage are much better than an electric hybrid and there is no compromise to power and performance. However, the biggest benefit however is the cost. To convert the Scuderi Engine to an air-hybrid, the cost is a few hundred dollars unlike an electric hybrid which adds thousands of dollars to the cost of the vehicle.

A ready supply of compressed air has additional benefits. Engine accessories and components can now easily be pneumatic - camless valve design for example. As long as the engine is running, there is a source of compressed air. External accessories can be operated such as air tools or other devices. This has major significance, especially in military applications.

These are only some of the features of the Scuderi Engine. Two proof-of-concept prototypes are currently being developed at the renowned Southwest Research Institute

I hope I was able to clarify some of the basics of the engine. Updated materials on the Scuderi Engine and its air-hybrid design will be available in the near future. This material will go into greater detail on the specifics of the technology.

Best regards, Sal Scuderi, President The Scuderi Group

--- end quote ---

Oujdeivß wrote:

The animation does more to explain it to the layman than anything else does..... But... The animation doubles the number of cylinders needed... Or... If 16:1 is the optimum fuel air ratio...... Then how do you take a burned 16:1 exhaust ratio, and use it as the intake charge, no matter the inlet psi? Just curious... Jeff (Without asking Nate ) Rice...