基于微压差测量技术的灭火剂浓度机载测试系统设计

Design of airborne test system for extinguishing agent concentration based on micro-differential pressure measurement technology

摘要:

为准确评测机载防火系统的灭火功能与性能,设计基于微压差测量技术的灭火剂浓度机载测试系统。通过真空泵采集灭火剂与空气复合气体,利用过滤器对其展开过滤后,传输至微压差浓度传感模块,经该模块的气体加热器加热该气体,温度控制器控制所加热气体温度,然后通过节流设备使其形成压差,利用压差传感器变更压差信号为电信号,再应用信号处理器展开信号处理,计算出灭火剂浓度并得出与其浓度值呈正相关的电信号；依据该信号,利用流量恒定设备高精度控制灭火剂与空气复合气体流量,合并该气体流量后将其输入稳压缓冲罐进行缓冲,通过气体分析仪测量灭火剂与空气复合气体差异浓度和压差的关联,输出灭火剂浓度数字信号,并利用排气口将测试完的灭火剂空气复合气体排入真空泵,通过真空泵将测试完的灭火剂空气复合气体排放至空气内。试验表明：该系统的测量范围大、测量数据有效且精准程度高,重复与稳定功能性好,灭火剂体积浓度与维持时长在常温下大于低温下。

Abstract:

In order to accurately evaluate the fire extinguishing function and performance of the airborne fire protection system, an airborne test system for the concentration of fire extinguishing agents based on the micro-pressure difference measurement technology was designed. The composite gas of fire extinguishing agent and air is collected by a vacuum pump, filtered by a filter, and then transmitted to the micro-pressure difference concentration sensing module. The gas is heated by the gas heater of the module, and the temperature controller controls the temperature of the heated gas, and then The throttling equipment is used to form a pressure difference, the pressure difference sensor is used to change the pressure difference signal into an electrical signal, and the signal processor is used to carry out signal processing to calculate the concentration of the extinguishing agent and obtain an electrical signal that is positively correlated with its concentration value; Signal, use constant flow equipment to control the flow of fire extinguishing agent and air composite gas with high precision, combine the gas flow and input it into a pressure stabilized buffer tank for buffering, and measure the correlation between the differential concentration and pressure difference between fire extinguishing agent and air composite gas through a gas analyzer , output the digital signal of fire extinguishing agent concentration, and use the exhaust port to discharge the tested fire extinguishing agent-air composite gas into the vacuum pump, and discharge the tested fire extinguishing agent-air composite gas into the air through the vacuum pump. The test shows that the system has a large measurement range, effective measurement data and high accuracy, good repeatability and stability, and the volume concentration and maintenance time of the fire extinguishing agent are longer at room temperature than at low temperature.