混合放电臭氧发生器中臭氧产生过程的传热数值模拟

Numerical Stimulation of Heat Transfer in Ozone Generation from Multi-discharge Ozonator

为揭示混合放电臭氧高效发生的电能转换和传热机理,采用有限体积法数值求解质量、动量和能量守恒方程,实现对混合放电臭氧发生进行传热分析,并实验验证了该方法的可行性。研究结果表明:气体进入两放电间隙后温度逐渐升高,且两放电间隙温度相差较大,内放电空间平均温度比外放电空间平均温度平均高6.38 K;中心电极、内电介质、外介电质和外电极各部分内部径向温差较小;混合放电仅36.14%的电能转换为热能,其中气体从3根放电管中携带的热量分别为9.85%,7.39%和4.78%,气体经过3根放电管后最高温度仅为313.2 K。混合放电电能转化率高、气体温度相对较低,是一种非常有前途的臭氧发生形式。

In order to understand the electrical energy conversion and the heat transfer mechanism in the multi-discharge ozone generation, we analyzed the heat transfer process by using the finite volume method to solve the mass, momentum, and energy conservation equations. The feasibility of this method was experimentally verified. The results show that after the gas flowing into the dual discharge gaps, the gas temperatures in the two gaps increase gradually and differ from each other greatly： the average temperature of the internal discharge gap is 6.38 K higher than that of the external discharge gap. However, there is only an inconspicuous difference among the radial temperatures of the central electrode, the internal dielectric, the external dielectric, and the external electrode. In this study, only 36.14% of the electrical energy has been converted into heat, including the energy loss caused by gas in the three tubes of 9.58%, 7.39%, and 4.78%, respectively. The maximal temperature of gas is only 313.2 K after it flows through three discharge tubes. Therefore, the multi-discharge ozone generation has a reasonably high valid conversion ratio of electrical energy as well as a relatively low reaction gas temperature; hence it is a promising way of generating ozone.