Study On Dust Dispersion Law Of Road Construction With CFD Simulation

Road construction has made travel more convenient,but also polluted the natural environment The atmospheric environment that we depend on for survival has been greatly damaged,and road construction dust is an important source of atmospheric pollutants.In the process of road building,especially in the phase of roadbed construction,the use of various construction machinery and the impact of natural wind,from the exposed soil or piles of materials will produce a lot of dust;and in the time of stopping construction,if there is outside interference,the dust generated and deposited during the construction process will start to rise again.These dusts will increase the concentration of atmospheric particles and cause damage to the surrounding natural environment,in which plants and animals will be affected,leading to an imbalance in the ecological environment and ultimately endangering people’s health.In this paper,we analyze the force situation of dust and the conditions of dust initiation,collect dust from construction sites and examine its particle size distribution.The theory of CFD numerical simulation is introduced to show the reasonableness of using CFD to simulate dustrelated issues.During the construction period,enclosures are usually used to control the dust diffusion,and the simulation software Fluent is used to simulate the dust concentration changes and movement trends in the fluid domain with enclosures.The following conclusions are drawn:(1)The movement trend of small-sized dust particles is similar to the vector diagram of air motion in the fluid domain,indicating that their locomotion mainly follows the air flow in space,and with the increase of particle diameter,their speed of settling in the process of locomotion is increased,indicating that they are influenced by gravity to an increasing extent;(2)Enclosure can effectively change the wind environment inside it,which reduces the wind speed to a smaller level;(3)Comparing the changes of dust concentration in the fluid domain with different particle sizes,it is found that the rate of dust escaping from the fluid domain increases first and then decreases.The larger the particle size of dust particles,the later the peak of its escape rate;(4)The overall trend,with the increase of dust particles,the total mass of dust escaping from the enclosure will decrease;(5)The design and comparison of the enclosure arrangement form,the effect of the incoming wind on the blocking of dust,and put forward a suitable enclosure arrangement;(6)With the distance between the enclosures increasing,the height of the enclosures reducing,with the increases in wind speed,the amount of dust escaping from the enclosures will rise,that is,the dust suppression effect of the fence is weakened;(7)Most of the particles that can escape from the range of the fluid field are particles of smaller size.Most of the large particles of dust particles movement stop in the fluid domain range.