Numerical and experimental investigation of flow characteristics in natural gas pipe

To measure the natural gas flow in the natural gas pipeline, a flow measurement method based on a laser Doppler velocimeter (LDV) is proposed, and the flow field in the natural gas pipeline is accurately measured. The flow laws of the flow field in the pipeline are obtained. In this paper, the influence of the jet flow on the flow field in the main pipe during the injection of tracer particles is analyzed by numerical calculations, and the reliability of the calculation is verified by the LDV test. The results show that the influence of the jet on the flow field in the main pipe weakens rapidly within a short distance, which provides good conditions for measuring the flow in the LDV test pipeline. The error between the flow measured by LDV and the turbine standard device is within 0.47%. Meanwhile, the uncertainty of the LDV measurement test system of a natural gas pipeline is evaluated. The system uncertainty is less than 2%, which satisfies the uncertainty requirements of the metering system, verifying the feasibility of the LDV metering flow and providing a reliable basis for the accurate metering of natural gas.