Ford’s German division has filed a patent for a new water injection system that could bring exponential improvements in efficiencies and high horsepower gains.
Truthfully, water injection isn’t a new technology, World War II fighter planes used vaporized water to improve low-speed thrust during take off, plus, an extra spurt of speed during dogfights. Post-war, both Saab and Oldsmobile offered vehicles with factory installed water injection systems before the technology enjoyed a renaissance in high-performance Group B rally cars during the ’80s.
Traditionally, water injection has been used as a short cut to high performance, where a 50/50 water-alcohol mix is injected into the intake manifold where it’s used to lower combustion temperatures and cool the pistons and cylinder walls. This, in turn, reduces the likelihood of detonation and allows for higher compression ratios, which can manifest as either higher performance metrics or a more efficient engine.
But where Ford’s design differs is its focus on injecting water directly into the combustion chamber instead of its traditional upstream location in the intake tract. To do this Ford is proposing a new type of injector which is fed by high-pressure fuel and water lines and is capable of injecting both fluids in order to control pre-detonation as the ECU uses a medley of valve control systems to optimize compression ratios on the fly.
A mini-piston within the injector moves longitudinally via a spring to expose passages which allow “knock control” or “secondary fluid” to flow down into a chamber in the injection nozzle which surrounds the tip of the fuel injector. This would allow for “water spray to circumferentially surround a fuel spray if water injection and fuel injection occur at the same time.”
But on the other hand, under certain conditions based on parameters provided by a myriad of engine sensors, the ECU might decide that fuel and water injection shouldn’t happen at exactly the same time. “If it’s undesirable for the fuel and water sprays to overlap the controller may determine that the desired water injection timing is before or after a time at which the injector injects fuel.”
Ford’s EcoBoost family of engines could benefit immensely from the introduction of this new water injection system. The vaporized water would help cool combustion temperatures which would reduce the reliance on Exhaust Gas Recirculation to curb excess NOx particulates, while also freeing flow from the exhaust that could be channeled through turbochargers and put to better use in performance applications.
There are also benefits to supercharged applications where a reduction in high cylinder pressures and exhaust temperatures could help slash fuel consumption during high-load, or high-boost events.
Theoretically, Ford could implement this technology up and down its lineup with simple tweaks to the ECU’s value lookup table– efficiency oriented parameters for regular offerings of the Fiesta, Focus, Fusion, Taurus, Escape, Edge, Explorer, and F-150; while more aggressive maps are used for Raptors, Mustangs, and other hot EcoBoost offerings.
Additionally, differences in secondary fluid could provide even more distinction between the different types of applications. Ford envisions some embodiments of its new system will generate their own secondary fluid by capturing exhaust, intercooler and A/C condensate, or even rainwater, while other applications could use a more traditional water-alcohol mix.
Ford of Europe has been hard at work on this pollutant reducing and mileage maximizing system since at least January 2016, seemingly as a response to the demonization of diesel in the Old World. If and when the system does make it to production expect it to arrive with one of Ford’s European developed EcoBoost motors in three or four-cylinder flavors.