Abstract: Because of the influence of low temperature,high speed flow and disturbance which make natural gas form hydrate to block pipeline,it is presented that by means of the transmission characteristic of mass flow rate pulse artificially generated at pipeline entrance in the pipeline,the timebreaking algorithm and TVD/Godunov hybrid formula is used to simulate numerically to not completely blocked pipeline,the pressure fluctuating history curves at the entrance are analyzed to determine the blockage location,length and strength of the gas pipeline.The technology provides the method and means for precisely detecting the blockage location and length at initial blockage time,working out correct pipelinecleaning operation plan and decreasing the risk of complete pipeline blockge.

Key words: gas pipeline, blockage positioning, TVD hybrid algorithm, pulse, numerical simulation