【摘要】 在自动消防系统中,喷射时间是实现及时扑灭火灾的一个关键性技术参数,必须准确。 本文根据流量与压力之间的流体力学原理进行了变量之间物理和数学的分析,并作了一些简化处理。建立了存储压力与时间的变量分离型一阶微分方程,进而得出喷射时间的理论公式。最后用试验数据进行修正而得出喷射时间的半经验半理论公式 某单位的灭火系统是按流体力学原理设计的,其中调压器室灭火系统,设计时按半经验半理论公式计算出喷射时间 t=9.58 sec,实测数据 t=8.9 sec,证实理论计算值与实际基本符合。因此,本文为自动消防系统提供了喷射时间的计算公式。更多还原

【Abstract】 For an automatic fire-control system, the spraying time is such an important parameter that it is necessary to ensure the fire-control against out-of-time. According to the relation between discharge and pressure based on the principle of fluid mechanics,the present paper gives a math-physical analysis to the relevant variables with an appropriate simplification. After a linear differential equation showing the pressure variation has been derived, the theoretical equation of the spraying time is then obtained by means of simple integration. With the modification by experimental data,finally,a semiempirical relationship of the spraying time for an automatic fire-control system may be expressed as follows.where z——number of pressure vessels;Vc——initial volume of nitrogen gas;Pc——initial absolute pressure of nitrogen gas stored};PE——final absolute pressure of nitrogen gas stored;n——number of spray nozzles;a——section area of a spray nozzle;K——constant for simplifying the calculation (see form. 2) ;Ψ——constant for simplifying the calculation (see form, 11) . An actual fire-control system erected in a voltage regulator room is cited as an instance for simulating. It has been designed on the basis of, the prin-ciple of fluid mechanics. It is found that the spraying time calculated by using the semiempirical relationship above is equal to 9.58 sec and so is relatively consistent with that measured (t = 8.9 sec) . Thus, such a semiempirical relationship may be considered effective for designing an automatic fire-control system.更多还原