一二次密封空间油气分布规律及影响因素

Distribution law of oil and gas in the primary/secondary sealed space and influencing factors

浮顶油罐一二次密封空间内的油气在雷击作用下可导致起火事故。为研究浮顶油罐一二次密封空间内的油气分布规律及影响因素,建立了浮顶油罐实验模型,在不同的外界风速和温度下,检测一二次密封空间内不同位置的油气体积分数,并进行油气扩散机理分析,合理假设未知参数,将实验模型的固有参数代入数值公式中,两者表征的油气变化情况较吻合,从而得出更为详细的油气分布规律及影响因素。结果表明:以背风点为起点,一二次密封空间内各处的油气体积分数不断升高,在迎风点附近油气体积分数达到最高;温度和风速的增加均可使一二次密封空间内油气分布差异增大,较温度而言,风速对其不均匀分布影响更为明显。

The oil and gas in the primary/secondary sealed space of fl oating-roof tank may cause fi re accidents under the action of lightning striking. In order to study the distribution law of oil and gas in the primary/secondary sealed space of fl oating-roof tank and infl uencing factors, a fl oating-roof tank experimental model is established. Under different wind speed and temperatures, the oil and gas volume fractions at different positions in the primary/secondary sealed space are detected and analysis of oil and gas diffusion mechanism is carried out. Through reasonablely assuming unknown parameters and putting the intrinsic parameters of the experimental model into the numerical formula, oil and gas changes presented by these two methods are in good agreement, thus more detailed distribution law of oil and gas and infl uencing factors are worked out. Results show that with the leeward point as the starting point, the oil and gas volume fractions at different positions of the primary/secondary sealed space rise all the way and reach up to the peak near the upwind point. The increase of temperature and wind speed can both make the distribution differences of oil and gas in the primary/secondary sealed space increase, and the infl uence of wind speed on the uneven distribution is more obvious compared with that of temperature.