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10年来,日本低速二冲程回流扫气机与直流扫气机均有所发展,其主要机型技术参数如表所示。 a.增大行程-缸径比S/D虽是提高热效率的有效措施之一,但螺旋桨直径将随行程S的加长而增大,由此将带来一些问题,诸如停靠的港口受到限制、船体尾部形状肥大、低速运转时船舶操纵性能差,此外,振动的起振力增大,制造成本上升等弊病。由于技术的不断进步,加上热循环理论的日益发展,目前实际发动机的S/D已高达3.82。增大S/D是提高增压器综合效率的重要因素之一,而今天的增压器性能却超越柴油机所要求的性能,这就意味着存在这样一种潜在可能性,即通过加长柴油机的有效作功行程可使燃油耗率再进一步下降。但如果综合考虑增压器综合效率的进一步提高、发动机扫排气、燃烧是否完善等技术因素时,则据据目前
In the past 10 years, both Japan’s low-speed two-stroke backflow scavengers and DC scavengers have developed. The technical specifications of their main models are shown in the table. a. Increasing the stroke-to-bore ratio S / D is one of the effective measures to increase the thermal efficiency. However, the propeller diameter will increase with the increase of the stroke S, which will cause some problems such as restricted landing of the port, Tail shape hypertrophy, poor handling performance at low speed, in addition, the vibrating starting force increases, manufacturing costs and other ills. Due to the continuous improvement of technology and the increasing development of thermal cycling theory, the actual S / D of the actual engine is as high as 3.82. Increasing S / D is one of the important factors in increasing the overall efficiency of the supercharger, and today the supercharger performance is beyond the performance required by the diesel engine, which means that there is a potential that by lengthening the diesel engine Effective work trip can make the fuel consumption rate dropped further. However, if we consider the comprehensive efficiency of the turbocharger to further improve, the engine exhaust gas, the combustion is complete and other technical factors, according to the current