Numerical Simulation of the Mixing Effect in Natural Gas Calorific Value Control.

In order to study the mixing effect of natural gas calorific value control process, this study establishes the pipeline models for the mixing of the natural gas with different calorific value, meshing for the pipeline models, and caries out the numerical simulation on the natural gas mixing for one branch pipe and one manifold by using ANSYS Fluent 16.0 software. Based on the distribution characteristics of the velocity Held and the components Held in pipeline after natural gas mixing, the effect of natural gas mixing is compared and analyzed. In addition, the effect of natural gas mixing is evaluated by analyzing the percentage of the gas components at different pipe diameter positions after natural gas mixing. The numerical results show that for the branch pipe nixing flow, the mixing effect is not as good as that of the manifold because of the low-speed stagnation area at the mixing corner. For the branch pipe mixing flow, the mixing is relatively sufficient and the gas components are relatively inform at the distance of 15D=3 000 mm from the mixing center. However, with the development of flow in the downstream, the mixing is still in progress. For the mixing flow of the manifold, the direction of fluid flow is changed due to the existence of the manifold, which aggravates the mixing of natural gas flow. Therefore, the mixing effect is better. At the outlet of the manifold, that is, the inlet of the branch pipe, the gas components have reached a relatively uniform state. [ABSTRACT FROM AUTHOR]