The dome roof tank (DRT) is always a main equipment for oil products storage. However, the mechanism of the heat and mass transfer for the oil vapor-air in the tank gas space remains unclear when the DRT is subjected to the solar radiation. Therefore, by considering storage conditions (e.g., the solar radiation intensity and liquid height) and taking n-hexane as a representative of light oils, and based on the Fluent software and user-defined functions (UDFs) programming, a two-dimensional calculation method and the relevant theoretical model were numerically developed to simulate and reveal the transfer mechanism under the complex storage process. Meanwhile, the feasibility of the model was verified by a self-built experimental platform for the DRT evaporation loss investigation. Under the solar radiation to a 1000 m³ DRT, the simulation results show: (1) The gas space temperature distribution can be accurately calculated, and the average temperature decreases with increasing liquid level; (2) There is a distinct counterclockwise eddy and an evident velocity boundary layer close to the wall and roof of the gas space, and the maximal gas velocity is within 0.08–0.49 m s⁻¹, which is closely related with the storage liquid height and time; (3) The vapor concentration in the gas space increases from top to bottom with an obvious high-concentration layer near the liquid surface, and the average concentration increases with increasing liquid level and storage time; (4) The static breathing losses increase positively with the liquid level. The mean daily loss rates for n-hexane are approximately 7.37 g t⁻¹, 20.9 g t⁻¹, and 6.36 g t⁻¹ for the spring equinox, summer solstice, and winter solstice, respectively. Further, the year-mean daily loss rates are about 11.5 g t⁻¹, and 20.1 g t⁻¹ for n-hexane and gasoline, respectively, and the correspondingly the total loss rates for a year are about 4.2 kg t⁻¹ and 7.35 kg t⁻¹. The research results can provide important theoretical support and design reference for reducing the breathing loss and improving the enterprise management level.

圆顶屋顶储罐（DRT）始终是石油产品存储的主要设备。但是，当DRT受到太阳辐射时，储罐气体空间中的油气蒸汽的传热和传质机理仍不清楚。因此，通过考虑储存条件（例如，太阳辐射强度和液体高度）并以正己烷为轻油的代表，并基于Fluent软件和用户定义函数（UDF）编程，进行了二维计算数值开发了该方法和相关的理论模型，以模拟和揭示复杂存储过程中的传递机理。同时，通过自建实验平台对DRT蒸发损失进行了研究，验证了该模型的可行性。在太阳辐射下达到1000 m ³DRT，仿真结果表明：（1）可以准确计算出气体空间温度分布，平均温度随液位的升高而降低；（2）逆时针方向有明显涡流，靠近气室壁和顶壁有明显的速度边界层，最大气体速度在0.08-0.49 m s ^-1以内，这与储液高度和储气高度密切相关。时间; （3）气体空间中的蒸气浓度从上到下增加，在液面附近有明显的高浓度层，平均浓度随液位和储存时间的增加而增加；（4）静态呼吸损失随液位而正增加。正己烷的平均每日损失率约为7.37 g t ^-1分别是春分，夏至和冬至分别为20.9 g t ^-1和6.36 g t ^-1。此外，正己烷和汽油的年平均每日损失率分别约为11.5 g t ^-1和20.1 g t ^-1，相应地，一年的总损失率约为4.2 kg t ^-1和7.35 kg t ^-1。研究结果可为减少呼吸损失，提高企业管理水平提供重要的理论支持和设计参考。