Abstract: Abstract: In order to improve the accuracy of the prediction of the drop point of the existing fire water jet, reduce the calculation intensity and improve the calculation efficiency, the mass distribution in the volume of the radial profile jet element in the current water jet stability stage was studied. Taking the average density inside the cell as the independent variable, the drag-dominated dynamic differential equation of jet cell was constructed, and the theoretical jet trajectory and expected landing point of jet cell with different average density were obtained by MATLAB GUI. On this basis, through the weighted error distance between the expected drop point and the theoretical fire source point, the drop point range of the actual water jet space can effectively cover the fire source, and achieve the purpose of rapid fire suppression. An 8 m external fire source was set manually as the test object of the prediction method, and the control effect was verified by testing the effluent extinguishing speed and effluent angle control instruction output time. The results show that the output instruction time is generally about 0.12 s; the fire extinguishing time is about 2.6 s, the fastest is up to 0.097 s.

Key words: Key words: jet drop point, weighted error distance, air drag, fire coverage effect, fire extinguishing speed