Abstract Currently, natural gas is known as one of the most important sources of human energy, an‎d due to the compressibility of natural gas, its transmission is carried out through pipelines at high pressures to prevent the thickening of transmission lines for economic reasons; however, due to the need of various consumers for lower pressures, it is necessary to reduce its pressure at the point of consumption. This is done by reducing the pressure energy stored in a pressure reduction station. The purpose of this thesis was to simulate the flow of the heater furnace with the ANSYS Fluent software an‎d its effect on the efficiency an‎d heat transfer rate of the furnace. In order to investigate the thermal behavior of the heater furnace tube with two models without a baffle an‎d with a baffle inside the tube with a water cooling system into which hot air enters, it is considered. The hot air flow enters the heater furnace tube with a temperature of 293.15 Kelvin an‎d a speed of 0.0158 m/s. The pipe wall is considered to have a heat flux of 32087 W/m. The results showed that the use of baffles has improved the heat transfer rate, that is, reduced the flow rate in the gas pressure reduction station. Also, the use of baffles has increased the heat transfer coefficient an‎d Nusselt number on the furnace surface. The highest heat transfer improvement in the case with baffles was achieved at a water temperature of 35 degrees Celsius, by 16 percent, an‎d a 7 percent reduction in gas consumption, an‎d the lowest increase in heat transfer improvement was achieved at a water temperature of 60 degrees Celsius, by 7.7 percent.

ابوالحسن عسگر شمسي , بهمن اسدي

هادي صفائي , مهدي رفيعائي