Obtaining Lower Engine-Out Emissions and Higher Efficiencies than Conventional Combustion Modes Via Water-Fuel Mixtures


Combustion modes have continually been improved to gain superior efficiency and emission characteristics, but there are numerous limitations on conventional processes. It is evident looking at how efficient traditional combustion modes and comparing the emissions that there is a need for improvement. The ratio of efficiency to emissions is far from ideal. Recently, the focus has been on Low-Temperature Combustion (LTC) modes as they offer significantly higher efficiencies as well as lower emissions compared to the conventional combustion modes. However, out of these combustion modes, most of them have limitations in what conditions they can be operated which potentially overshadows their benefits. There is a very narrow range of operating conditions due to the lack of control over the combustion process in certain LTCs. Hence, there is a need for a new process/method to be implemented with a combustion method to maximize efficiency while minimizing emissions.


This technology focuses on an advanced combustion mode known as Thermally Stratified Compression Ignition (TSCI). This combustion mode revolves around forcibly stratifying the temperatures in the cylinder before the ignition steps begin, and this process allows for a level of control on the overall combustion process. Originally, this technology uses direct water injection into the cylinder to provide the forced thermal stratification through the evaporative cooling of the injected water. Even though this method worked relatively well, it has the specific disadvantage of requiring a separate injection system to inject the water along with the obstacles of filling the water tank separately from the fuel tank or recover the water from the exhaust. The specific process disclosed within this technology involves TSCI combustion from water-fuel mixtures rather than the direct water injection. This eliminates the need for any hardware changes to the engine architecture as the process can be done using a single injection system. The water and fuel will effectively mix with each other through the process of water-fuel emulsion, a process that also lowers the temperature of the mixture. Alternatively, if alcohol fuels are used, emulsion is not even necessary as water and alcohol fuels are miscible. Using multiple injection events via the single direct injection system allows for this technology to be as efficient as it is. The first injection occurs early in the intake stroke to allows time for the mixture to evaporate and become mostly homogenous with the air. The second injection occurs in the late compression stroke to make sure it doesn't mix with the rest of the charge before combustion begins. The goal of the second injection is to introduce the necessary amount of thermal stratification to control the combustion process. Multiple injections can be used to carry water and fuel to the system, thus having a charge cooling effect without affecting the level of thermal stratification in the cylinder.


- The same or higher efficiency when compared to conventional diesel combustion. - Significantly lower NOx and soot emissions than conventional methods. - Dramatically improved controllability through the manipulation of the in-cylinder temperature distribution prior to ignition.  - Single-injection system that is much more commercially attractive to automotive manufacturing companies because it eliminates the need for any hardware changes to the engine.


This technology can be used for cars, trucks, and any other manufactured products that have compression ignition.

Patent Status

Provisional patent

Stage Of Development


Licensing Potential

Development partner,Commercial partner,Licensing

Licensing Status

Available for Licensing

Additional Info


https://stonybrook.technologypublisher.com/files/sites/h7lqlhhbrnapiaojn3ie_pixnio-1877664-4632x3068.jpeg Source: https://pixnio.com/transportation-vehicles/cars-automobile/car-automotive-diesel-engine-vehicle-drive-fuel-chrome-gasoline, CC0.
Patent Information:
Case ID: R050-8950
For Information, Contact:
Donna Tumminello
Assistant Director
State University of New York at Stony Brook
Benjamin Lawler
Sotirios Mamalis
Mozhgan Rahimi Boldaji