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Test data have been used to implement a detonation model that allows to predict water injection effects. Results have shown that water injection really represents a new way to avoid detonation, to reduce compression work and to control NOx formation in SI engines. ...Though analysed by a few researches, the practice of water injection in Spark Ignition Engines (SI-ICE) does not yield homogeneous results, owing to various typologies of engines used for experiments. ...In this paper the effects of water injection in the intake pipe are investigated from both a theoretical and experimental viewpoint.

Several researchers have advocated water injection as an approach to replace or supplement existing knock mitigation techniques. Water, having high latent heat of vaporization, acts as a heat sink and reduces temperatures in the end gas zone, thereby reducing the tendency for auto-ignition. ...It is worth to note that most of the research work done on water injection focuses on extending permissible engine power output. However the current trend toward boosted and downsized engines demands extending the knock limit without increasing exhaust temperatures or specific fuel consumption (which are the major limitations of existing knock mitigating techniques). ...This paper examines the prior research in using water injection to extend knock limit in boosted spark ignition engines, and its potential effects on performance and emissions.

Of the 3 methods, 2 add water in air and one adds water in fuel. The Water-in-Air methods are valve port injection of water or spraying water continuously into the turbocharger inlet. ...The numerical and experimental investigation of NOx and soot emission reduction by 3 methods of water addition to a Diesel engine has been presented. Of the 3 methods, 2 add water in air and one adds water in fuel. ...Experimentally these two methods of water in air are considered. Numerical investigations of the chemical kinetic aspects of the combustion of n-heptane/water mixture are performed assuming the model of concentric shells of a homogenous reactor.

Cost analysis is made of three methods of increasing airplane performance by water injection, namely: 1. By increasing cruising bmep's while maintaining engine cooling requirements at the value for conventional cruising bmep's. 2. ...By increasing cruise powers up to meto at a constant F/A ratio while maintaining low cooling requirements and avoiding detonation with the use of water. It is concluded by the author that if the water to be used for cooling does not displace an equivalent weight of payload, a maximum saving of 7% at sea level and 18% at 25,000 ft can be realized in direct operating cost with water. ...A STUDY of possible economic advantages to the aircraft operator of utilizing the internal cooling potentialities of water to assist aircraft-engine cooling and increase detonation limited powers is presented here.

Setting up the geometrical compression ratio focusing on ethanol properties could rise both ethanol and gasoline energy efficiency, as water injection can control knocking phenomena through managing combustion chamber temperature. ...This paper aims to show how water injection technology enables high efficiency flex fuel engines development, focused on ethanol performance, granting to Brazil a smoother path through future national fleet electrification. ...The energy efficiency in Mega Joules per Kilometer, improved through higher geometrical compression ratio, enhanced up to 7.3% (from 1.59 to 1.47 MJ/km) in a natural aspirated port fuel injection vehicle and up to 4.8% (from 1.85 to 1.76 MJ/km) in a turbocharged direct injection vehicle.

This paper presents simulation and experimental results of the effects of intake water injection on the main combustion parameters of a turbo-charged, direct injection spark ignition engine. ...The paper initially presents the main results of a one-dimensional simulation analysis carried out to highlight the key parameters (injection position, water-to-fuel ratio and water temperature) and their effects on combustion (in-cylinder and exhaust temperature reduction and knock tendency suppression). ...This paper presents simulation and experimental results of the effects of intake water injection on the main combustion parameters of a turbo-charged, direct injection spark ignition engine. Water injection is more and more considered as a viable technology to further increase specific output power of modern spark ignition engines, enabling extreme downsizing concepts and the associated efficiency increase benefits.

The engine was outfitted with a sequential port water injection apparatus. Under full-load, water injection enabled operation with 87 AKI fuel at near optimal combustion phasing, and with a stoichiometric air-fuel ratio. ...A detailed comparison on combustion phasing, burn rate, Mean Effective Pressure, water requirement, and efficiency is presented in this paper. ...Under full-load, water injection enabled operation with 87 AKI fuel at near optimal combustion phasing, and with a stoichiometric air-fuel ratio. This resulted in up to a 5% improvement in Net Mean Effective Pressure and up to a 34% improvement in thermal efficiency compared to the production ECU Calibration.

One way to minimize these is the usage of exhaust gas re-circulation (EGR), Miller cycle and water injection. The reduced knocking tendency allows the geometric compression ratio to be increased further, which leads to an additional efficiency advantage. ...One alternative to conventional diesel propulsion is the usage of stoichiometric natural gas combustion. Due to the lowered C/H ratio and the cost effective exhaust after treatment (EAT) in form of a three way catalyst (TWC), less CO2 is emitted and it is possible to comply even with most stringent NOX legislations. ...However, the stoichiometric combustion of natural gas has also disadvantages. In particular, the throttling and retarded 50 % mass fuel burned (MFB50) positions due to knocking lead to efficiency losses.

Ultra-low soot and NOx emissions as well as a significant fuel consumption improvement, relative to conventional diesel combustion, were obtained with the novel 2-zone combustion chamber. The novel 2-zone combustion system allows later, ignition controlling, diesel injection timings to be used while maintaining low UHC and CO emissions. ...The projection provides a means to control the mixture formation and combustion phasing within each zone. The novel combustion system was applied to reactivity controlled compression ignition (RCCI) combustion in both light-duty and heavy-duty diesel engines. ...A novel 2-zone combustion chamber concept (patent pending) was developed using multi-dimensional modeling.

Dissolved water is a normal component of jet fuel which is vapourised during combustion; however, free water is a contaminant that can starve engines, freeze to form ice crystals capable of blocking fuel feeds, support microbial growth, and contribute towards corrosion. ...This investigation seeks to identify novel chemical approaches to the dual management of both water contamination and ice formation in jet fuel. ...We anticipate that this class of FDII represents a novel approach towards protecting jet fuel against the effects of water contamination.

Aiming to further improve Diesel engine fuel efficiency and exhaust emissions, we conducted evaluation of a newly devised Diesel Injection Shear-Stress Advanced Nozzle (DISSAN) where two jets were formed separately and then interacted into the nozzle exit.

This is one of the first studies to compare droplet breakup models and AdBlue injection with high injection pressure (Pinj=200 bar). The breakup models compared are the Reitz-Diwakar (RD), the Kelvin-Helmholtz and Rayleigh-Taylor (KHRT), and the Enhanced Taylor Analogy Breakup (ETAB) model. ...A novel high pressure SCR spray system is investigated both experimentally and numerically. RANS simulations are performed using Star-CD and polyhedral meshing. ...The models are compared with standard model parameters typically used in diesel fuel injection studies to assess their performance without any significant parameter tuning. Experimental evidence from similar systems seems to be scarce on high pressure AdBlue (or water) sprays using plain hole nozzles.

This paper describes the preliminary development of a wash water recycle system utilizing an inside-skinned hollow-fiber membrane developed by Bend Research, Inc. ...During the NASA research program, a pre-prototype membrane module capable of processing 6 gallons per day (2.3×10-2m3/day) of wash water at 97% recovery was developed that can be dry-stored and that weighs 120 g.

The introduction of CO₂-reduction technologies like Start-Stop or the Hybrid-Powertrain and the future emissions limits require a detailed optimization of the engine start-up. The combustion concept development as well as the calibration of the ECU makes an explicit thermodynamic analysis of the combustion process during the start-up necessary. ...The combustion concept development as well as the calibration of the ECU makes an explicit thermodynamic analysis of the combustion process during the start-up necessary. Initially, the well-known thermodynamic analysis of in-cylinder pressure at stationary condition was transmitted to the highly non-stationary engine start-up. ...But with a fraction of nearly 45% of the burned fuel energy, the wall heat is very important for the calculation of energy balance and for the combustion process analysis. Based on the measurements of transient wall heat transfer densities during the start-up presented in a former work, the paper describes the development of adaptations to the known correlations by Woschni, Hohenberg and Bargende for the application during engine start-up.

The validation process was carried out by comparing the dINJ instrument injection rate with the corresponding quantity obtained by a conventional injection analyzer during simultaneous hydraulic tests. ...In the present paper an innovative approach for the shot-to-shot hydraulic characterization of low pressure injection systems is experimentally assessed. The proposed methodology is an inverse application of the Zeuch’s method, which in this case is applied to a closed volume upstream the injector instead of downstream of it as in conventional injection analyzers. ...The proposed methodology is an inverse application of the Zeuch’s method, which in this case is applied to a closed volume upstream the injector instead of downstream of it as in conventional injection analyzers. By this approach, the well-known constraint of having a finite volume pressurized with the injected liquid downstream the injector is circumvented.

The development of custom engine control software allowed predetermined event-by event control of individual cylinder fuel injection and spark settings. A dual injection strategy was studied with both an early and a late injection. ...This study reports on the development of a novel methodology for capturing and quantifying unburned hydrocarbon emissions (HC), CO, and CO2 on a cycle-by-cycle basis during an engine cold start. ...The method was demonstrated by applying it to a 4 cylinder 2 liter GTDI (Gasoline Turbocharged Direct Injection) engine for cold start conditions at an ambient temperature of 22°C. For this technique, the entirety of the engine exhaust gas was captured for a predetermined number of firing cycles.

The precise, fast and wide range measurement of exhaust gas oxygen concentration is a key element to the development of low emissions combustion engines. This is true to Gasoline Direct Inject and Common Rail Diesel engines, but even standard Multi Port Injection ( MPI ) engines benefit from a better lambda control ( SULEV applications ). ...This is true to Gasoline Direct Inject and Common Rail Diesel engines, but even standard Multi Port Injection ( MPI ) engines benefit from a better lambda control ( SULEV applications ). The proliferation of linear oxygen sensors has up to now been hindered by a lack of compatibility of sensors / interface electronics among different suppliers, keeping the cost high.

The Citotech system injects compressed air into one combustion chamber to move the piston downwards and into another combustion chamber, on the compression stroke, for combustion. Combustion is achieved with control of ignition and fuel injection. This process repeats and cranks the engine until it starts. ...The Citotech system injects compressed air into one combustion chamber to move the piston downwards and into another combustion chamber, on the compression stroke, for combustion.

In a previous study, we demonstrated that the isobaric combustion cycle, achieved with a split injection strategy, can be more suitable for the double compression expansion engine concept than the conventional diesel combustion cycle. ...The present work is focused on understanding the effect of different injection strategies on the heat release, efficiency, and emissions of isobaric combustion at the peak cylinder pressure of 150 bar. In situ injection rate measurements are performed to improve our understanding of the heat release rate shape and pollutant formation. ...The effect of altering the injection strategy on the isobaric combustion cycle is also studied at a constant equivalence ratio.

The concept of JPIC (Jet Plume Injection and Combustion) is introduced as a radical refinement of DISC (Direct Injection Stratified Charge). ...In operation, rich air-fuel mixture is admitted thereby first to a lean charge in the cylinder, forming a turbulent jet plume, and, thereupon, the process of combustion is executed using a pulsed jet of combustion products created upon ignition, by means of a conventional spark discharge, of the mixture remaining in the cavity of the PJC generator. ...The system for its implementation consists of a fuel injector and a PJC (Pulsed Jet Combustion) generator (described in our previous papers) connected in series via a check valve.