Article

Analysis of Water Jet Trajectory of Auto-Targeting Fire Sprinkler System in Interior Large Space

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Abstract

Auto-targeting fire sprinkler system is an intelligent fire extinguishing equipment that used in interior large space. An auto-targeting fire sprinkler system was designed; the compositions and working principle were also expounded in detail. The water trajectory equation was deduced and simulated by Matlab software according to the principle of particle kinematics, ballistics, and fluid mechanics. The relationship among working pressure, pitch angle, installation height and jet range, flow landing speed was analyzed. The results show that the fire sprinkler system can satisfy the design requirements, and the water trajectory equation basically concides with the actual situation, which can provide some theoretical references for the fire precision location.

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... Through the analysis of forces in the air, the water jet trajectory equation, under the action of many influential factors, was established, and a simulation analysis of the jet trajectory of a fire gun was carried out by using MATLAB software, this method [14] overcame the problem proposed by Wan feng [12] by not constraining the working pressure and the flow parameter. Hu Guoliang and others [15] pointed out that due to a series of external factors, even if the water is injected into the space at the centre of the fire, the final flow point may exceed the scope of the margin of error for effective extinguishing. Therefore, considering gravity and the air resistance of a water flow, a force analysis was carried out. ...
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