Study On The Influence Of Micro/nano-scale Bubble Flow Premixed Fuel On Engine Performance

In recent years,micro-nano-bubbles have attracted much attention due to the physical and chemical characteristics of the theory of macro bubbles and the application of sewage treatment,biomedical engineering and nanomaterials.Different macro bubbles brought by the fuel supply system at the meeting,micro-nano bubbles have many unique positive properties.Micro-nano-bubbles are small.According to the study of the diameter of the micro-nano-air bubble that affects the combustion,the diameter of 100-200 nm.The micro-nano gas bubble in this range can effectively improve the economy and emissions of fuel burning in the engine;Micro-nano-bubbles can be stable in liquid for a few days.With these properties,the micro-nanometer bubbles are applied to the pre-processing of fuel,which can promote combustion through physical and chemical effects,increase the oxygen content of fuel,increase fuel economy and reduce pollutant emissions.Therefore,it is necessary to further study the mechanism of fuel in the combustion process of fuel in the combustion process of micro-nano-bubble fuel fuel.This study is based on a single-cylinder optical engine equipped with a high-speed photography experiment platform.The impact of the change of the concentration of bubbles and fuel characteristics with micro-nano-foam current diesel as the target fuel.High-speed cameras collect the development process of combustion flames,and use a double-color temperature measurement method to conduct in-depth analysis of flame images and find the temperature field and KL factor field in the cylinder during the combustion process to reveal the rules of carbon smoke during the combustion process,explore the micro-nano foam foaming during the combustion process,and explore micro-nanozoic bubbles The improving potential of the flow fuel on the production of carbon smoke.The main research content and conclusions include:In order to improve the degree of evaporation of fuel atomization and fire,the quality of fuel is optimized.By pre-processed diesel through the two methods of independent research,so that diesel and air are pre-mixed at different times to make M10,M20,M30 and W5,W10’s micro-nano-bubble current diesel.After detecting the bubble concentration of W5> M20> M30> W10> M10,the average particle size of the air bubble in the micro-nano foam fuel is about 200 nm.Two types of microfelinal fuels and conventional diesel have been used to change the preparation time to change the preparation time to obtain the effect of experimental fuel to explore the effects of bubble concentration on the changes in the combustion and temperature field.From the perspective of flame brightness and flame area,diesel>m20>m30>m10,diesel> W5> W10;from the obvious observation of the flames to the order of the flames from first to the back,M20 was earlier than that of M30≈m10 in conventional diesel.Earlier than W5 earlier than W10.In the cylinder voltage and heat-draining curve,as the bubble concentration increases,the peak of the cylinder pressure increases,and the peak of the heating rate decreases with the increase of the concentration.Reduce.At the same time,it was found that the combustion high-temperature area pixels were reduced except for the M20,and the pixels of low temperature area increased more,indicating that the low-bubble concentration of micro-nano-foam current diesel played a positive role in reducing the high temperature zone when burning.W5,M30,and conventional diesel have been obvious on the development of the flames and temperature fields with low bubble concentrations and changes in the temperature field.The influence of the field.As the time of fuel injection is advanced,the starting point of the three fuel burning is advanced,and the peak of cylinder pressure has also risen,and the peak of the heating rate decreases.The flame area and flame brightness of conventional diesel and M30 show a trend of increased first and then decreased.The w5 is opposite to the trend of decreased first and then increasing.The formation trend of high-temperature zones is similar,and the effect of W5 in the effect of inhibiting carbon smoke generation is stronger.At low load,M30 and W5 have a less combustion point during the combustion process of conventional diesel during the combustion process.The flame area and flame brightness are smaller,and less high-temperature areas are generated.Under the high load,the cylinder voltage heat control curve of the three fuels of three fuels is small.The two micro-nano-foam flow fuels are significantly higher than the conventional diesel during the combustion process.In the area,the amount of carbon smoke is also produced,and it does not achieve the effect of inhibiting the production of carbon smoke.Under low jet pressure,the M30 is similar to the curve of conventional diesel cylinders,while the peak and the peak peak of the W5 cylinder compression rate are significantly less than the first two.During the combustion process;The number of pixels in conventional diesel high-temperature zones is significantly more than the other two types of micr-nano-foam-like fuel,and more carbon smoke is also generated.Under high jet pressure,the peak peak of micro-nano-foam fuel cylinder pressure is slightly higher than conventional diesel;the flame area and flame brightness is slightly smaller than conventional diesel;the gap between the number of high temperature area and the number of pixels is not obvious;the gap between the production of carbon smoke is small.