基于微元体动力学的压缩空气泡沫射流轨迹研究

Prediction of compressed air foam jet trajectory based on microbody dynamics

压缩空气泡沫喷射轨迹是影响泡沫灭火效能的关键因素之一。针对目前缺乏准确的泡沫射流轨迹模型的问题,基于质点运动学、流体力学、外弹道学理论,并结合试验数据对参数修正,提出压缩空气泡沫经消防水炮喷射轨迹的理论预测模型。采用四阶Runge-Kutta算法对泡沫射流微元体动力学微分方程进行求解,利用MATLAB软件进行泡沫射流理论轨迹仿真,探究不同参数对射流理论轨迹的影响。选择特定工况分别进行仿真和试验研究,对比发现:理论模型所预测的射流轨迹与实际泡沫射流轨迹基本吻合,故所建动力学微分方程较为准确,可为压缩空气泡沫在举高车辆的实战应用提供理论依据。

The injection trajectory of compressed air foam is one of the key factors affecting foam extinguishing efficiency.In view of the lack of accurate foam jet trajectory model at present,a theoretical prediction model of compressed air foam through the trajectory of fire water spray is proposed based on particle kinematics,fluid mechanics,external ballistics theory and experimental data.In addition,the four order Runge-Kutta algorithm and MATLAB software is used to solve the differential equation of the foam jet micro element,and to simulate the theoretical trajectory of the foam jet.Furthermore,the influence of different parameters on the theoretical trajectory of the jet is explored.It is found that the predicted jet trajectory is basically consistent with the actual foam jet trajectory,and the kinetic differential equation is more accurate,which can provide a theoretical basis for the actual application of compressed air foam in lifting vehicles.