Author:
Podvalny S L,Kutsova E V,Vasiljev E M
Abstract
Abstract
The paper solves the problem of predicting the emergency states of gas pipelines in cases where the initial parameters of the pipeline are not fully known a priori and can change during operation. The coefficient of heat transfer from gas to the external medium and the coefficient of internal viscous friction of hydraulic resistance are considered as such parameters. The theoretical calculation of these coefficients with sufficient accuracy for practice is very difficult due to the significant uncertainty of the actual conditions of heat transfer along the route and the current state of the pipeline. To solve this problem, a mathematical model of a steady gas flow in a pipeline is proposed, which is based on the assumptions about the polytrophic nature of the gas, as well as the non-isentropic and nonadiabatic nature of its flow. Together with the model, a method for identifying undefined coefficients has been developed. The problem of building the corresponding computational procedures with unknown boundary conditions is solved. An analysis of emergency states of a gas pipeline for cases of complete rupture and partial destruction of its wall was carried out by means of numerical modeling. Examples of using the developed model for predicting emergency states of gas pipelines are given.