天然气地下储气库垫层气与工作气混合的模拟研究

天然气地下储气库的建筑是调节城市用气不均衡性、平抑供气峰波动的最合理有效的手段之一，在储气库进行注采动态运行时，避免注入气与垫层气发生混合是关键技术问题，本文通过分别建立三维两相渗流模型和三维气体扩散模型，采用跳跃式的求解方法，首先求出库内各点瞬态压力分布，再根据达西定律确定出速度分布，最后通过求解三维气体扩散数值模型，可动态的确定垫层气的需求量和注采天然气所需的最佳储气压力，残存气与储存天然气的混合而导致的回采气体浓度的变化，为保证储库满负荷的优化运行提供科学依据。

Simulation research of mixing problem to the cushion gas and work gas

In order to meet the requirement of city seasonal peak for gas consumption, construction of the underground gas storage reservoir is one of the first reasonable and available both in technology and economy. At dynamic operation of the underground gas storage rreservoir, it is a pacing technology to avoid cushion gas and work gas mixing. By establishing three dimensional, two phase flow model and three dimension gas diffusion model, applying a leap frog type solution technique, demand quantity of the cushion gas and work gas ?gas concentration that gas and gas mixed ? the optimum injection and production pressure were defined. The results of example shows that this model can offer scientific reference for underground gas storage reservoir optimization operation.