基于超声雾化的柴油/汽油混合燃料液滴群燃烧特性

利用超声雾化多液滴制备系统,制成了柴油/汽油混合燃料多液滴群,其中液滴直径、液滴浓度、液滴速度等参数均可独立调节,以模拟内燃机缸内喷雾的实际流动及其与空气的混合状态。将该多液滴群引入可控活化热氛围燃烧器中,并对其稳定燃烧后的燃烧特性进行了研究。结果表明:改变混合燃料掺混比、燃料进给速度、空气流量等参数后,多液滴群自燃火焰形状随之发生显著改变,随着燃料中柴油所占比例的增大,火焰起升高度增加,火焰宽度减小;燃料进给速度和空气流量的改变,影响了混合燃料的燃空当量比及中央射流出口速度,进而影响到燃料的燃烧特性。

Combustion characteristics of diesel-gasoline blend fuel based on ultrasonic atomization technology

Droplet swarm of diesel-gasoline blend fuel is prepared on an experimental system based on ultrasonic atomization technology.The mean droplet diameter,air/fuel ratio and droplet speed are independently adjustable to simulate the flow and mixing conditions of the spray in the cylinders of internal combustion engine.The droplet swarm is imported into a Controllable Active Thermo-Atmosphere Combustor(CATAC) to investigate the steady combustion characteristics of the droplet swarm.Results show that changing the diesel-to-gasoline mixing ratio,the fuel feeding speed and air flow leads the shape of spontaneous flame changes significantly.As the diesel component increases in the blend fuel,the lift-off height of flame increases,while the width of the flame decreases.The variations of fuel feed speed and air flow influence the equivalence fuel-to-air ratio and the central jet velocity,thus greatly influencing the fuel combustion characteristics.