Numerical Evaluation of the Hydrothermal Process in a Water-Surrounded Heater of Natural Gas Pressure Reduction Plants

The gas pressure in the main network of transmission lines is about 700 to 1000 psi (4826.33 6894.76 kPa), which reduced 250 (1723.69 kPa) at entrance station a city. This reduction process, occurs regulator, causes severe drop temperature. temperature produces hydrates and even water vapor freeze. As result, there possibility that passage regulator blocked flow cut off. By employing heaters (indirect heaters), entering can be preheated eliminate freezing regulator. heater fueled with natural it operates for 24 hr day, especially cold seasons. Therefore, one challenges using this type its high fuel consumption. Consequently, researchers are looking solution reduce consumption (natural gas) heaters. In paper, heat transfer fluid plant, Aliabad Power Plant (Iran), numerically investigated commercial Computational Fluid Dynamics (CFD) code, ANSYS FLUENT 18.2. considered consists three parts, including (i) coils, (ii) bath (shell), (iii) fire tube. indirect process takes place between hot liquid tube (combustion exhaust) convection flows generated bath. Numeric modeling performed four different mass flows, 6 × 104, 8 1 105, 12 105 standard cubic meters per hour (or 16.67, 22.22, 27.78, 33.33 m3/s). results indicate outlet achieved higher than required. installing on burner, reduced, resulting cost savings, also reducing environmental impacts. outcomes depict maximum possible reductions monthly economic savings proposed system 67,500 m3 IRR 25 million rate 60,000 SCMH.