ИЗМЕНЕНИЕ ТЕМПЕРАТУРЫ НАГРЕТОЙ ЖИДКОСТИ ПО ДЛИНЕ ТРУБОПРОВОДА В РЕЖИМЕ ЗАПОЛНЕНИЯ

Abstract

In this paper we consider the temperature conditions to be filled hot uninsulated underground pipe fluid. The mathematical formulation of the problem includes partial differential equations describing the temperature change in the fluid flow in a pipeline environment. The analytical solution of equations was carried out by methods of operational calculus. The dependence of the fill fluid piping temperature on the distance from the injection point, time interval from the start of filling the pipeline parameter, the surrounding soil and the liquid itself this solution unlike other is, in particular, that the derivation of unused heat transfer coefficient of the fluid into the environment. This ratio varies greatly in the soil warms up, depends on a number of factors that can not be fully accounted for and, therefore, introduces additional error in the formula, considering it. To assess the reliability of solutions comparison was made with the results of the studies described in the literature. In the first of those surveyed work presents the results of measurements of the temperature of the liquid during filling of the underground section of the oil pipeline Uzen - Guriev. Calculated by the formula curve fairly well describes the nature of the distribution of the experimental points. The relative standard deviation is 6.7%. It was also compared with the results of numerical modeling of the process of filling the pipeline with a diameter of 0.8 m heated by oil. The discrepancy between the results amounts to a few tenths of a degree. The calculated dependencies can be used to assess the options for safe filling and withdrawal of «hot» pipeline on steady operation.