化学氧呼吸器生氧装置防护性能数值模拟

Numerical simulation on protective performance for the O_2 generator of a chemical oxygen respirator

以实验室化学氧呼吸器生氧装置为研究对象,建立了二维轴对称数学模型,对生氧装置防护性能进行了数值模拟.首先通过模型验证实验验证了模型的合理性,其次对比研究了劳动强度、入口CO2体积分数、生氧药剂颗粒当量直径以及入口管径对生氧装置防护时间和出口温度的影响.结果表明:劳动强度和入口CO2体积分数对生氧装置防护性能影响显著,高劳动强度和高CO2体积分数均会引起防护时间缩短以及出口峰值温度升高;颗粒当量直径与防护时间近似呈负相关线性关系,12 mm颗粒的防护时间比6 mm颗粒少32.15 min,但是大粒径颗粒会使得出口峰值温度显著降低;入口管径对生氧装置防护时间和出口温度的影响均非常有限.

A 2D axisymmetric mathematical model was developed for an O2 generator and the protective performance of the O2 generator was simulated. The model’ s rationality was verified by experiments under typical operational conditions. Then, the influ-ences of labor intensity, inlet CO2 volume faction, equivalent diameter of oxygen-generating particles, and pipe diameter at the entrance on the protective performance of the O2 generator were studied by the model. The simulated results show that both labor inten-sity and inlet CO2 volume faction have significant effect on the protective performance of the O2 generator. A higher labor intensity and a higher inlet CO2 volume faction share the same trend, which means a much shorter protective time and a much higher outlet peak temperature. The protective time decreases with increasing equivalent diameter of oxygen-generating particles, exhibiting an approxi-mately negative liner relationship. The protective time for 12 mm particles is 32. 15 min shorter than that for 6 mm particles. However, larger particles will lead to a lower outlet peak temperature. Different from the front three factors, pipe diameter at the entrance has limited effect on both the protective time and outlet temperature.