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An experimental investigation of fuel consumption, exhaust emissions and heat release was performed on a prototype 1.2 liter 4 cylinder turbocharged CNG engine, which has been specifically developed and optimized in order to fully exploit natural gas potential. More specifically, the combination of a high CR of 10.1:1 and a Garrett high-performance turbocharger featuring selectable levels of boost produced a favorable efficiency map, with peak values exceeding 35%. The experimental tests were carried out in order to assess the engine performance improvement attainable through turbocharging and to define the best control strategies for this latter. The investigation included ample variations of engine speed and load, RAFR as well as trade-offs between boost level and throttle position. At each test point, in-cylinder pressure, fuel consumption and ‘engine-out’ pollutant emissions, including methane unburned hydrocarbons concentration, were measured.

A 2.0 liter displacement gasoline fueled car, with closed-loop control and 3-way catalyst, was adapted to operate on CNG (Compressed Natural Gas). A system allowing the detection and measurement of aldehydes, ketones, polycyclic aromatic hydrocarbons (PAH) and speciated organic materials was set up. Running on different fuels, such as CNG, gasoline and gasoline/oxygenates blends, tests were carried out according to US (FTP '75) and European (ECE+EUDC) procedures with and without the original 3-way catalytic converter. Apart from the absence of evaporative emissions because of the required closed delivery system, test results pointed out that CNG use yields substantial air toxics benefits in terms of regulated and, above all, unregulated emissions.

This paper provides a comprehensive description of the present status of the Water Pump Subassembly (WPSA) that will be part of the Active Thermal Control System of the Pressurized Modules of Columbus, the Attached Laboratory (PM4) and the PM2 of the Man Tended Free Flyer. Description of major components of the Subassembly are presented along with the results of trade-offs performed and rationals for concept selection.