寒区油气集输管道合适埋深数值计算

Numerical calculation of the appropriate buried depth of oil and gas pipelines in cold areas

油气集输管道的敷设深度直接影响管道的建设成本,对管道的安全平稳运行也起重要作用.考虑寒区土壤的初始温度周期性变化、地表不同日平均温度以及是否冻结等因素,建立数学模型,并采用有限单元法对多种埋设深度的集输管道土壤温度场进行数值计算.实例计算表明:0.8 m是寒区较合适的管道埋设深度.当大气温度升高时,可适当减小集输管道的埋深,以节省建设成本.在集输管道运行管理计算分析时,可以不考虑冻结及非冻结状态物性对土壤自然温度场的影响,将土壤看作常物性.该模型可为寒区油气集输管道的敷设提供一定的理论依据.

The buried depth of oil and gas pipelines has direct influence on the construction cost of them,and it is also important to the safe and steady operation of them.The mathematical model of the temperature field in the soil around the buried pipeline is established,in which the cyclic change of the initial temperature of the soil,the different average surface temperatures in a day and the freezing of the soil are considered.The temperature fields of a case under different buried depths are obtained by using finite element method.The results show that 0.8 m is the more appropriate buried depth of the pipelines in the area.When the atomsphere temperature rises,the buried depth can be decreased in order to reduce the construction cost of the pipelines.Whether the soil is frozen can be not considered in the model because it has little influence.The study results of the paper can provide theoretical reference for the laying of the oil and gas pipelines in the cold areas.