Supercritical Fuel Injection (SCFI) technology
We will implement SCFI technology, known as the “fourth state of matter” where a liquid (fuel) is no longer liquid nor totally gas.
Because diesel is heavy, viscose, and less volatile than gasoline, not all the fuel is burned during combustion, resulting in carbon compounds being released as harmful particulate soot. The higher combustion temperatures required to burn diesel also lead to increased nitrogen oxides emissions. By raising diesel to a supercritical state before injecting it into an engine’s combustion chamber, viscosity becomes less of a problem. Additionally, the high molecular diffusion of supercritical fluids means that the fuel and air mix together almost instantaneously. So instead of trying to burn relatively large droplets of fuel surrounded by air, as current diesel/gasoline engines do, the vaporized fuel mixes more evenly with air, which makes it burn more quickly, cleanly, and completely. Engine emissions using SCFI are reduced by >80% based on high compression 18:1 engine. Using low compression, the reduction may exceed 90%. This has also proven a 10-15% engine fuel reduction. A 25%-30% reduction is possible, pending engine optimization for the next generation engines.
All pertinent issues have been resolved, namely that of the coking of the diesel and proper injector design to achieve supersonic velocities operating a two-phased fuel mix.
SCFI test results were independently proven during testing by two different major national labs. Namely, Sandia National Laboratories and National Institute of Standards and Technology (NIST).
Gryphon Diesel engines due to SCFI technology will employ a low pressure fuel injection, up to 1,500 bar, which is far less expensive and very common than current near 3,000 bar or higher proposed systems.
We propose the use of supercritical fuel injection (SCFI) for superior “near-zero” green diesel engine emissions and lower brake-specific fuel consumption (BSFC).
Multi-point Laser Ignition (MLI)
Using the MLI system, instead of using ceramic igniters, is also a very strong option. Laser Ignition is essentially optical breakdown of gas molecules inside the combustion chamber. It has been tested on 18:1 compression engines using only regular fuel injection (not with SCFI), and it is operational. This can reduce NOx emissions by 69% and CO and CO2 emissions by 50% using a single laser. If a braided double-laser beam is used, it was tested and proven to reduce close to 95% of all NOx emissions. It also allows to operate an extremely lean mix (>75:1) and ignition of the fuel mix at any temperature is guaranteed without any misfire. All tests have proven these numbers. Increase in brake thermal efficiency (TE) up to 3%. Improved combustion stability with laser ignition aimed within the fuel spray, for best results. During testing, MLI has also proven to virtually eliminate flame propagation due to the thorough ignition of the fuel as a whole. MLI system reduces emissions sharply and compensates for a much slower velocity of combustion due to low compression. MLI may also yield an additional 5% fuel reduction (NOT included in the above fuel reduction estimates). MLI system is controlled by the engine’s electronic control unit (ECU) for exceptional engine performance. MLI testing was done over a two year period by two different teams with similar results.
Fuel Reconditioning Device (FRD)
Diesel fuel has the longest molecular hydrocarbon chain of all fuels used in internal combustion (IC) engines. Hydrogen has the smallest molecule.
The combustion efficiency of a hydrocarbon is associated directly with the amount of the molecules’ surface area that is exposed to oxygen. The reason that a small, short-chain hydrocarbon burns more efficiently is that more of the molecules’ surface is exposed to oxygen. When a fuel molecule reacts with oxygen, heat is produced and if only carbon dioxide and water vapor are left behind, this is known as complete combustion. Complete combustion yields zero emissions. Zero emissions is the target Gryphon Diesel Engines is seeking, thus the reason the FRD is to be employed.
The FRD discharges a high-voltage electric current at a specified frequency and wavelength into the fuel. It breaks the diesel long chain hydrocarbon molecules into shorter, lighter more volatile molecules. As a consequence, the quantity of the more volatile, short-chain hydrocarbons is increased, although the total number of atoms remains the same. This reconditioned diesel fuel become more flammable and burn more completely in the combustion chamber.
This process yields additional advantages:
- density increases
- pressure increases
- boiling point decreases
With the breakdown of cyclic aromatic hydrocarbons, it increases both the highly explosive hydrogen gas molecules and it increases the more volatile low-weight hydrocarbons.
The net results is:
- hydrogen molecules are lighter and move much faster; thus they have more molecular collisions with oxygen
- combust more completely
- burn much faster
- ignite at a lower temperature
- produce more horsepower per unit of fuel burned
- reduces fuel consumption
- distribute power more evenly for smoother performance
Employed together with SCFI system, which already yields “near-zero” emissions, the fuel reconditioning treatment leaves behind virtually no unburned hydrocarbons, thus reducing emissions to a “zero” level.
During a year-long testing of the technology in Europe, a device was installed in a Euro 3 rated diesel engine. The testing proved the emissions moved to Euro 5, a two classes jump. A second testing was conducted in a hotter climate in Barbados. The results recorded an average increase of 10% in fuel efficiency and a noted significant decrease in particulate matter emissions, resulting in much less visible exhaust smoke. Polluting emissions and fuel consumption have been an enormous problem throughout the Caribbean islands.
Emulsion Fuel Device (EFD)
The EDF device is optional, to be added for marine, power generator and hybrid powerplants applications. It allows to blend up to 15% of potable water with diesel fuel producing an emulsion blend. It may reduces the diesel consumption by 10%-15% (not accounted in previous calculus) and on a stand alone operation it reduces emissions, NOx up to 30%, PM up to 90% and CO2 up to 15%. Operating costs are substantially reduced with much cleaner burn, lower exhaust temperatures and extended engine life. Potable water is less expensive than diesel fuel. Together with FRD system, it may produce an exceptional complete combustion due to the high volume of hydrogen molecules in water.
The only requirement is to add fresh/potable water source up to 15% of the hourly burn rate. The EFD process causes no corrosion or wear problems as the water is in the inverse phase of the emulsion, never comes in contact with moving parts. The EFD delivers an un-stabilized product which requires no further treatment and inhibits the micro-explosion phenomenon.
The system logged over 100,000 highway miles of road testing in a Mack class 8 truck. It was conducted by James Madison University in 2014. The system works with diesel fuels #1, #2, #4.