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介绍利用加热风洞在各种条件下对玻璃球喷头的热反应所做的调查。所考虑的反应参数是响应时间指数（ＲＴＩ）、传导参数（Ｃ）和相变参数（ＣＨＰ）。分别利用１个以及２个或３个反应参数的结合预测各种风洞试验条件下以及慢、中、快成长速率的火灾中的反应时间。计算指出，这些风洞试验结果无法在所用热反应模型的框架内得以充分的解释。与正常预置条件温度时的情况相比，试验时提高喷头的预置条件温度会导致ＲＴＩ数值增加。对ＲＴＩ数值增加的合理解释可能是玻璃球内的温度梯度导致了时间延迟。这表明，以前利用使玻璃球破碎所需要的功解释的ＣＨＰ很可能反映着热延迟所产生的影响。评价热反应模型采用了火灾成长条件下喷头反应时的计算放热速率。对于快、中、慢火灾成长速率而言，不管是根据２个参数（ＲＴＩ和Ｃ）的计算，还是根据３个参数（ＲＴＩ、Ｃ和ＣＨＰ）的计算，喷头反应时的放热速率均相差不多。然而，当仅使用ＲＴＩ值时，喷头反应时的预测放热速率便发生显著的下降。
The investigation of the thermal response of glass ball nozzles under various conditions using heated wind tunnels is presented. The reaction parameters considered are Response Time Index (RTI), Conduction Parameter (C) and Phase Change Parameter (CHP). A combination of one and two or three reaction parameters was used to predict reaction times in various wind tunnel test conditions and in slow, medium, and fast growth fires. The calculations indicate that the results of these wind tunnel tests cannot be fully explained within the framework of the thermal reaction model used. Compared with the case of the normal preset temperature, increasing the preset temperature of the nozzle during the test will increase the RTI value. A reasonable explanation for the increase in the RTI value may be that the temperature gradient in the glass bulb causes a time delay. This shows that the CHP explained previously using the work required to break the glass spheres is likely to reflect the effect of thermal delay. The evaluation of the thermal reaction model uses the calculated heat release rate when the sprinkler reacts under fire growth conditions. For fast, medium and slow fire growth rates, whether based on the calculation of two parameters (RTI and C) or on the calculation of three parameters (RTI, C, and CHP), the rate of heat release during head response is uniform. almost. However, when only the RTI value is used, the predicted heat release rate at the nozzle response is significantly reduced.