缩放喷管内的气固两相流动和缩放喷管长度的研究

采用一元流动理论和拉格朗日方法,研究了用于气、固两相分离试验装置的缩放喷管内,被气流拖曳的颗粒加速率与颗粒大小和缩放喷管长度的关系.研究表明,在气流参数和缩放喷管长度不变的情况下,被气流拖曳的颗粒越大,颗粒在缩放喷管出口处的速度就越低;在颗粒加速率相同的情况下,颗粒越大,所需的喷管长度就越长.为了更好地实现气、固两相分离,颗粒在缩放喷管出口处的速度应该足够大,因而缩放喷管就应该足够长.

Study on Gas-Solid Two-Phase Flow in Laval Nozzle and Laval Nozzle Length

Based on one dimension flow theory and Lagrange method, the correlation of speeding rate of particles under gas flow drag with the size of particles and the length of Laval nozzle used for the gas and solid two-phase separation test apparatus was studied. It is shown that with the decrease in size of particles, their velocity at the exit of Laval nozzle increases under the conditions of both the invariable gas parameters and the same Laval nozzle length; the Laval nozzle length increases with the size of particles under the same speeding rate of particles. In order to separate gas and solid two phases completely, the velocity of particles at the exit of Laval nozzle should be high enough, therefore the Laval nozzle should be long enough.