DBR Efficiency

A great deal of energy is lost in each cycle of a traditional piston driven engine. The DBR Engine specifically works to minimize this energy loss:

1) The power output of a DBRE is continuously variable. For conventional engines power is constant relative to the RPM. When driving at a constant speed, a conventional engine will produce a specific amount of power, and consume a specific amount of fuel, irrespective of whether it is needed or not. On the other hand, the DBRE’s output can change on the fly to meet specific power demands. The power output can change from 40 to 400HP in a split second!

This is accomplished by varying the packets of air and fuel. As the packets get smaller, lesser horse power is produced but the burn efficiency is higher. Excessive compression is not built up, but instead an “ultra lean” condition is achieved. An additional advantage of this ultra lean mix is lower combustion temperature and NOX emissions.

2) Conventional engines suffer from ‘pumping loss’ because the pistons are working against themselves and are also forcefully sucking and blowing gases. This is the primary reason why engines must waste fuel idling - which is neither efficient nor environmentally friendly. By dynamically metering the power stroke gases, the DBRE is fed with just the requisite amount of fuel which eliminates the so-called pumping loss. Fuel can be metered down to a pilot flame or even stopped. Once stopped, the DBR can be turned by releasing high-pressure air from an accumulator.

There is no need to idle and waste fuel while stationary in traffic. Full power is available from zero RPM. Stored compression and fuel are simply introduced again and ignited. In the final analysis, this really does represent the epitome of the efficient and environmentally friendly “stop and go” engine.

3) Regenerative braking can have a tremendous impact on both fuel efficiency and the environment. While slowing down or at a complete stop, even the ultra lean fuel consumption can be eliminated. Compression produced by braking is stored in an accumulator which can later be used to motor the engine for short periods, or to instantaneously boost intake pressure like a turbocharger.

4) Each cycle can be treated as a separate process and optimized for thermodynamic efficiency. External combustion can be better controlled. Heat recovered from the exhaust gases can preheat the compression gases, while the compression gases simultaneously cool the hot section. This is a common inter-stage heat recovery principle used in turbines.

5) Further efficiencies are possible with DBRE designs that are unheard of in piston engines. Pulsed modulation of combustion gas can be shortened, effectively lengthening the power stroke to extract more work [heat] before it is exhausted. Variable compression ratios are possible.

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