Around the previous 24 months, Ford Motor Company has designed significant commitments to the potential of its battery-electrical car or truck business enterprise. The corporation announced desire-pushed production bumps for its two BEVs, the Mustang Mach-E and the incoming F-150 Lightning pickup truck. Options for two battery factories in Kentucky and just one in Tennessee had been specific, together with a BEV mega campus in Tennessee. Even much more sizeable, the firm programs an internal restructuring separating the internal combustion and electric powered automobile plans into respective silos. Amidst all the superior-profile BEV information, Ford engineers have been quietly exploring means to continue to keep the interior combustion facet of the small business healthier, including a new process of hydrogen combustion.
Identified by MC&T in the U.S Patent and Trademark Place of work databases, Ford has made a system of combustion letting a turbocharged hydrogen-fueled engine to run across a huge assortment of air/fuel lambda values based on torque calls for. Internal exhaust gas recirculation (EGR) and valve timing would be applied to control combustion.
Lambda is the Greek letter applied to depict a fuel’s stoichiometric benefit as 1.00. The stoichiometric worth of a fuel is the ratio by which all of the fuel is put together with all of the oxygen to deliver a comprehensive burn. Gasoline engines have a stoichiometric worth of 14.7:1, meaning 14.7 elements of air to 1 aspect gasoline equals a lambda of 1. Lean combustion is represented as a worth increased than 1.00, although richer mixtures are demonstrated as considerably less than 1.00.
For the most aspect, a gasoline engine can run in a range from 8:1 at the richest to 18.5:1 at the lean stop of the spectrum. Lambda is calculated by diving the air/gas ratio into the stoichiometric worth of the fuel–so the richest gasoline combustion mixture is represented as .54 lambda, though the leanest is 1.25 lambda. Ford’s new process of turbocharged hydrogen combustion seems to take a look at lambda values in excess of 2.00. That means the motor would be able of operating in an very lean point out, making use of extra than double the sum of air demanded for the stoichiometric combustion of hydrogen.
Out there facts indicates hydrogen’s stoichiometric worth is in the 34:1 selection, so if Ford is managing hydrogen combustion at a Lambda of 2.00 or over and above that signifies the motor has an air/gas mix of at the very least 68 parts air to 1 part hydrogen. For what it is really worth, Mike Copeland’s hydrogen converted LS engines are working at 100:1 with the assist of a supercharger. Hydrogen is able of combusting at these kinds of lean air/gasoline mixtures mainly because of the fuel’s lower impedance to ignition. At stoichiometric values hydrogen has an particularly rapidly flame pace, it’s explained as around an order of magnitude a lot quicker than gasoline. The increased flame pace suggests there is a substantially increased prospect of detonation, even so, if the combination is leaner, the flame pace is diminished.
For Ford’s system of hydrogen combustion to operate the hydrogen would be released by way of immediate injection, letting gasoline and air to be managed independently of a person another in comparison to making use of port injection, which mixes the air/gasoline upstream of the combustion chamber. Provided utilizing DI, hydrogen is capable of furnishing 15% far more electricity than gasoline.
Applying a frequent fuel enter, the amount of money of EGR can be altered to go the article-combustion lambda price from 1.00 all the way to 2.00 or earlier mentioned. Under larger torque needs when the combination is richer in hydrogen, EGR move would be elevated to minimize the temperature in just the combustion chamber, therefore lowering the probability of pre-ignition. This is correct mainly because the recirculated exhaust gasoline enrichens the hydrogen combination by displacing the air that would generally be existing in the chamber. Don’t forget, a combustion motor results in utmost electricity from a marginally loaded air/fuel mixture, while a leaner mixture is better for fuel overall economy. A lean combine fundamentally is made up of less fuel than a richer one particular. When torque needs are lower and the hydrogen engine is working leaner, less EGR would be delivered.
According to the patent, the EGR articles could be altered by shifting the valve timing or by introducing sizeable overlap. Ford is searching at a “multi-raise profile” in which “the inlet valve performs two mutually unbiased valve strokes in the course of one particular performing cycle.” This could be obtained through “a 2nd valve stroke currently being performed ahead of the genuine valve stroke of the inlet valve.” All of this would be managed by a fully variable valve controller capable of altering the duration and valve stroke.
And lastly, Ford claims the hydrogen combustion motor could be element of a hybrid powertrain. The instance demonstrated involves a motor-generator unit placed in sequence between the engine and the transmission, but Ford claims it could be utilized in a parallel, a collection, or a series-parallel hybrid motor vehicle. Pairing a hydrogen combustion system utilizing very lean air/gas mixtures with a motor-generator is useful since the electricity density of a hydrogen-air combination at lambda values in surplus of 2.00 is incredibly small when compared to stoichiometric.
Hold in mind, Ford’s patent only covers the system of combusting and managing hydrogen mixtures. A lot more operate would have to be completed to create an engine layout capable of optimizing this strategy. The form of the combustion chamber and the best of the piston have a significant influence on combustion, and both of those would have to be shaped to get gain of hydrogen’s distinctive combustion properties.
Most promising even though, hydrogen can just take advantage of a hugely oversquare bore-to-stroke ratio due to the fact unburned hydrocarbons are not a concern, parasitic losses are also lessened applying a limited-stroke structure. This signifies engines able of screaming to 20,000 rpm could be probable in a normal grocery-getter, reversing the existing pattern of characterless beneath sq. engines.