Mathematical modeling of the heating process in a vortex tube at the gas distribution stations

Abstract

In all sectors of the national economy of Ukraine, issues of energy efficiency and saving of fuel and energy resources are important. Legislative changes in the branches and scientific developments of scientists allow reducing the energy dependence of Ukraine on imported fuels. One of the energy-saving measures for the transportation of natural gas is the use of a vortex tube for heating natural gas at gas distribution stations. Natural gas is heated before the process of reducing it in the gas pressure regulator to prevent the formation of crystalline hydrates within the gas pressure regulator. The complexity of the implementation of such a measure is the explosion of the fire hazard of natural gas, which makes it impossible to conduct a sufficient number of experimental studies to determine the required characteristics of the vortex tube for operation at the gas distribution station. Therefore, for the wide introduction of a vortex tube at gas distribution stations, a generalized mathematical model should be developed that would allow describing the process of heating the vortex tube of a working gas with different thermophysical parameters. In this paper, the thermodynamic and physical bases of the process of heating the compressed gases in the vortex tube are considered and the main parameters that influence the operation of the vortex tube are determined. The mathematical model of the process of heating the natural gas in a vortex tube is scientifically substantiated and improved. To improve the mathematical model of the natural gas heating process in the vortex tube, loss of dynamic pressure was determined on each characteristic section of the vortex tube and the degree of heating therein. Moreover, the mathematical model proposed by the authors allows us to determine the thermal power of the vortex tube and the amount of heat needed to heat the working gas in the vortex tube.

Diagnosis of three types damages to the ventilation system

“…As a result stagnant unventilated areas in the room are formed due to insufficient air jets long-range [31]. Air distribution devices have a high coefficient of aerodynamic resistance ζ and the ventilation system becomes energy consuming [18,22]. Thus, the air stream long range becomes too low and needs to be increased [31].…”

Diagnosis of damage to the ventilation system

“…This indicates excessive flow turbulence, excessive attenuation of air velocity and temperature, and a significant advantage of friction (viscosity) over dynamic forces. As a result, air distributors have a high coefficient of aerodynamic resistance, which negatively affects the ventilation system as a whole, as it becomes energy consuming [25]. This results in the fact that the long range of the air jet becomes too low and needs to be increased.…”

Two Diameters Method for Binding Sites in Hydraulic Calculation of Pipeline Systems

“…Since the continuity equation is valid, this fact leads to an even greater increase in velocity in the nozzle of the conical diaphragm. Obviously, when transporting flammable substances in these industries (chips, sawdust, other wood waste, cotton down, coal powder, flour) can be a fire situation (Labay et al, 2019). This makes it possible to avoid the unacceptable threat of using only spray schemes (Fig.…”