【作者】

Gerhard Ranegger,Gerhard Kogler

【摘要】

论文已在中国上海举行的第27届CIMAC大会上发表。论文的版权归CIMAC所有。 Future emission limits for maritime engines call for dramatic reduction of particle matter, NOx and SOx in emission regulated areas. With the expected demand for ultra clean propulsion systems the engine industry has started development of gas fuelled engines. Gas fuelled ferries have been oper- ated successfully in Norway, tug boats will follow soon.These ships are propelled by spark ignited engines.Since many more years dual fuel and tri fuel engines are in service powering LNG ships and off shore oil and gas rigs. Most of these engines are using LNG which is used in bone dry condition. The absence of any oil mist or oil vapour implies special challenges tothe equipment in contact with this gas, in particular thesolenoid valves which are used for ported fuel injection suffer from excessive wear reducing engine service intervals and causing reliability problems. Compliance with stringent protection systems and safety regulations-like mandatory double wall sealing of the gaspiping system-impose other challenges on to the de-sign of such ported fuel valves. The authors present a novel design of ported fuel injection valves for large bore engines which incorporates design elements successfully deployed for ported fuel valves for cryogenic hydrogen fuelled internal combustion engines. By use of special combination of material for the sealing ele-ments to avoid cold welding which leads to increases leakage a longer life time can be achieved. The new design is prepared for leak detection systems and in-corporates unique solutions with respect to the elec-trical connections and wiring to comply with existing regulations. Stable operation of the gas fuelled engine requires high repeatability of valve operation and low valve to valve variances.A low lift concept de-rived from Hoerbiger experience in compressor valve design reduces response time for more accurate gas metering. In conjunction with the need to operate the fuel valves in a large operating range the valves have to work under elevated differential pressure exhibiting only insignificant leakage. In applications with two stage turbo charger and increasing gas supply pres-sure the leakage of the PFI valves become even more important. In this paper a method will be presented how to fulfil this requirement by a non-pressure balanced concept and reduce closing time at the same way in order to avoid post injections or residual gas in the air manifold. The electromechanical design of the presented solution copes with these challenges, thusoffering the engine designer a new means to realize efficient and reliable maritime engines complying with tomorrow's emission regulations.

【会议名称】

第27届CIMAC会议

【会议地点】

上海

【下载次数】

2

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