New ways to improve the efficiency of railway transportation of viscous petroleum products

Abstract

The paper proposes a new approach to solving the problem of increasing the economic efficiency of railway transportation of viscous petroleum fuels (fuel oils) at low air temperatures. The physical properties of fuel oils allow them to be obtained when poured into the tank of a tank wagon in a stratified state, when their density in the upper part of the tank is significantly less than in its lower part. This blocks the natural convection of hot fuel oil on the cold walls of the tank, and it cools only due to the molecular thermal conductivity which is very small. Upon cooling down, a relatively thin highly viscous layer forms on the inner walls of the tank of a tank wagon, which acts as a heat-insulating shell, and the bulk of it (more than 90%) retains high temperature and fluidity throughout the period of transportation. The thermal and hydrodynamic calculations were performed using modern computer technologies (the ANSYS 5.6 software package). The results obtained show that the need to heat up the fuel oil during unloading remains, but already requires significantly less time and heat energy. The proposed energy-saving technologies for the delivery of viscous petroleum products are especially relevant in Russia with its cold continental climate, long-haul transportation, and the current structure of the country’s wagon fleet. The value of the results obtained lies in the fact that the proposal can be implemented on tank wagons in circulation with minimal change to their design. The technology of operation of the drain equipment at unloading points will not change either.