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THE main purpose of this paper is to illustrate the results or effects of water and water-alcohol injection on aircraft-engine performance. Water offers the best rate of cooling at high power output and, the authors point out, should be used without any additive where cooling is of paramount importance.

In this paper, a novel membrane-based phase separator is described. This device, known as a water recovery heat exchanger (WRHEX), overcomes the inherent deficiencies of current phase-separation technology. ...Specifically, the WRHEX cools and removes water vapor or water droplets from feed-air streams without the use of a vacuum or centrifugal force. ...As is shown in this paper, only a low-power air blower and a small stream of recirculated cool water is required for WRHEX operation. This paper presents the results of tests using this novel membrane device over a wide range of operating conditions.

Real-time monitoring allows analysis of water processing from wastewater to potable water and would enable the rapid diagnosis and correction of a processing failure if a water-related health issue were to arise. ...Through the NASA Small Business Innovative Research (SBIR) program, Lynntech has developed a novel, mesofluidic Total Organic Carbon Analyzer (TOCA) for real-time monitoring of water quality. ...Monitoring the quality of astronaut potable and hygiene water is one of the highest priorities of a regenerative life support system for manned space missions to the ISS, Moon, Mars, and other remote locations.

The performances of heavy-duty natural gas engines have been limited by combustion temperature and NOx emissions for a long time. Recently, water injection technology has been widely considered as a technical solution in reducing fuel consumption and emissions simultaneously in both gasoline and diesel engines. ...This paper focuses on the impacts of intake manifold water injection on characteristics of combustion and emissions in a natural gas heavy-duty engine through numerical methods. ...The results show that the quantity of injected water does not have a negative effect on water spray and film at an appropriate position, but an increase in the quantity of injected water leads to a negative effect on charging efficiency and a decrease in IMEP.

In this regard, water injection into the intake of a heavy-duty diesel engine to reduce peak combustion temperature and thereby reducing NOx is found to be a promising technology. ...Current work involves the use of 1-D thermodynamic simulation using AVL BOOST for modeling the engine performance with water injection. Mixing Controlled Combustion (MCC) model was used which can model the emissions. ...Further to this, the water injector module was integrated to inject decided quantity of water from the experiment to get optimum emission reduction. 3D CFD analysis using CONVERGE was carried out in-order to assess the water spray characteristics. A selection of water injector based on the required injection quantity was carried out and engine experiments were carried out based on the recommendations of the simulation results.

This configuration results in minimal airplane payload weight penalties because it uses less than half the water of the compressor water misting method. The combustor water injection method reduces the turbine inlet temperature just enough during takeoff that it would greatly improve engine hot section life which would reduce engine maintenance costs. ...The two current preferred methods of water injection are: (1) direct injection into the combustor, and (2) misting of the conditioned water before the engine's compressor. ...In order to reduce these temperatures and improve engine life, both water injection systems were evaluated for use all the way to top of climb. Although the water misting system showed better engine performance results, the best solution may be the combustor injection method when used for takeoff only.

In this exhaustive study, first a comparative investigation is conducted between diesel and 10% emulsion; and in the consequent phases, performance and emission characteristics of 10% water diesel emulsion is evaluated at various injection angles on a single cylinder, water cooled diesel engine. ...Some of the fuel, which includes biodiesel, alcohol-diesel emulsions and diesel water emulsions etc. Among which the diesel water emulsion (DWE) is found to be most suitable fuel due to reduction in particulate matter and NOx emission, besides that it also improves the brake thermal efficiency. ...In the comparative study for different injection angles, it is found that on advancing the injection angle the peak pressure is shifted towards TDC and because of that, torque is increased slightly.

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.

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.

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.

Additionally, a water injection system is integrated. All three technologies are investigated on their own and in combination. ...To reduce longer combustion durations caused by Miller valve timing and charge dilution, a piston bowl with extra high turbulence generation is designed. ...The results show, that high swirl motion and high turbulence can lead to a disadvantage in efficiency despite faster combustion durations due to higher wall heat losses. However, by using suitable combinations, it is possible to minimize throttle losses in low load operation and achieve optimum combustion locations (8°CA aFTDC) at full load operation with conventional compression ratios (ε=12).

For ultra-light aircraft, needing a total installed propulsion power up to 150 kW, the combination of a specifically developed internal combustion engine (ICE) integrated with a state-of-the-art electric system (electric motor, inverter and battery) appears particularly promising. ...The paper describes the design of the new engine, with particular attention to the optimization of the scavenging system (without poppet valves) and the design of a low pressure direct injection system. The process is supported by CFD 1D and 3D simulations. As far as the design of the injection system is concerned, the main goal was to obtain a fuel trapping ratio higher than 95%, along with a properly stratified charge at combustion onset, when considering the most critical operating condition (maximum engine speed and load). ...As far as the design of the injection system is concerned, the main goal was to obtain a fuel trapping ratio higher than 95%, along with a properly stratified charge at combustion onset, when considering the most critical operating condition (maximum engine speed and load).

Introducing water in a diesel engine has been known to decrease peak combustion temperatures and decrease NOx emissions. ...This however, has been limited to stationary and marine applications due to the requirement of a separate water supply tank in addition to the fuel tank, thereby a two-tank system. Combustion of hydrocarbon fuels produce between 1.35 (Diesel) and 2.55 times (Natural Gas) their mass in water. ...Combustion of hydrocarbon fuels produce between 1.35 (Diesel) and 2.55 times (Natural Gas) their mass in water. Techniques for extracting this water from the exhaust flow of an engine have been pursued by the United States department of defense (DOD) for quite some time, as they can potentially reduce the burden of supply of drinking water to front line troops in theater.

In this work, DME is applied in a direct injection compression ignition combustion application. A novel plunger-type injection system was used to pressurize DME to 415 bar. ...The ultra-low smoke characteristic of DME avoided the classical NOx-soot trade-off of diesel-fueled engines, allowing for combustion optimization through stronger exhaust gas dilution. DME showed improved combustion completeness likely owing to the self-containing oxygen and higher volatility minimizing the dependency on mixing with the in-cylinder surrounding compressed charge. ...Compression ignition internal combustion engines provide unmatched power density levels, making them suitable for numerous applications including heavy-duty freight trucks, marine shipping, and off-road construction vehicles.

Electrooxidation of urine and waste water ersatz was experimentally demonstrated. This paper discusses the electrooxidation principle, reaction kinetics, efficiency, power, size, experimental test results and water reclamation applications. ...This paper discusses the electrooxidation principle, reaction kinetics, efficiency, power, size, experimental test results and water reclamation applications. Process operating potentials and the use of anodic oxidation potentials that are sufficiently low to avoid oxygen formation and chloride oxidation are described. ...The design of a novel electrochemical system that incorporates a membrane-based electrolyte based on parametric test data and current fuel cell technology is presented.

Valving of gas to overcome airship lightness is wasteful and costly, especially when the craft is inflated with helium gas but, if this is not done, some substance must be collected and stored at the same rate as that at which fuel is consumed in the engines and the most practicable method seems to be to recover water from the exhaust gases. Gasoline combustion is analyzed and it is brought out that, for every 100 lb. of gasoline burned, 145 lb. of water is present in the exhaust, varying somewhat with the weather conditions and the composition of the fuel. ...Gasoline combustion is analyzed and it is brought out that, for every 100 lb. of gasoline burned, 145 lb. of water is present in the exhaust, varying somewhat with the weather conditions and the composition of the fuel. ...The problem is to make available, as ballast, two-thirds of the water known to be present. How it is present is explained and means for its utilization discussed.

Due to a catalytic reaction within the catalyst, NOx is converted nominally into Nitrogen and Water. Currently, the evaporative process is enhanced by aggressive mixer plates and long flow paths. ...In this study a novel biomimetic effervescent aqueous urea injector, its design inspired by the natural spray phenomenon of the Bombardier Beetle, is used to compare against a market-leading aqueous urea doser in comparable exhaust conditions with and without aggressive mixer plates being installed. ...In this study a novel biomimetic effervescent aqueous urea injector, its design inspired by the natural spray phenomenon of the Bombardier Beetle, is used to compare against a market-leading aqueous urea doser in comparable exhaust conditions with and without aggressive mixer plates being installed. The novel biomimetic effervescent injector operates by increasing the temperature of the Urea solution inside a constant volume chamber to its saturated vapour pressure.

The strategy couples the well-established capabilities of reagent-based flow injection analyses (FIA) with our novel concepts for the design of a miniaturized, low-power pumping system, i.e., an electrochemically-driven micropump. ...This paper describes the development of a prototype fluid pumping system for incorporation into a miniaturized flow injection analyzer. The strategy couples the well-established capabilities of reagent-based flow injection analyses (FIA) with our novel concepts for the design of a miniaturized, low-power pumping system, i.e., an electrochemically-driven micropump.

For selection of an optimum COM preparation system, a series of tests on high intensity ultrasonic mixing devices is performed. A brief description of the system is presented. A coal-fuel oil-water mixture up to 25% coal concentration has been used as an alternative fuel in China standard Model 195-2 Single cylinder, 10 H.P. at rated 1800 RPM and Model 2135 Two cylinders, 40 H.P. at rated 1500 RPM diesel engines with very encouraging. Preliminary tests results are given in this paper.

Three different injection strategies (single injection, pilot-main injection, main-post injection) are experimentally investigated on a heavy duty compression ignition engine. ...The results show that all three injection strategies produced ultra-low soot emission, while less NOx emission was noticed for pilot-main injection because of less diffusion combustion mode. Pilot-main injection strategy decreases the maximum pressure rise rate effectively compared to single injection. ...Partially premixed combustion is a single fuel variant of this new combustion concepts applying a fuel with a low cetane number to achieve the necessary long ignition delay.