Numerical Analysis of Efficiency of Mixing the Fuel Gases in a T-Joint with the Lateral Pipe Diameter and its Insertion Angle Alteration

Abstract

The paper presents numerical study of the processes in mixing the multicomponent gas flows in a T-joint with the lateral pipe different diameters and its insertion angle of 90°. Methane with the mass flow rate of 10 kg/s and temperature of 60 °C was supplied to the main pipe with the D1 = 254 mm diameter. The mixture of three gases (methane, hydrogen and nitrogen) with the r_CH4 = r_H2 = 0.4, r_N2 = 0.2, mole fractions, mixture flow rate of 10 kg/s and temperature of 90 °C was supplied to the secondary pipe. The lateral pipe diameter was varying in the D₂ = (0.6--1.0)D₁ range. Fields of speed, temperature and mass fractions of the mixture components in the main pipe were obtained for the different D₂ / D₁ values. The D₂ / D₁ optimal value was determined, ensuring the required composition homogeneity and mixture temperature in the main pipe at the 20D₁ distance the mixing start. Simulation was also performed for a T-joint with pipes of the same D₁ diameter and the 60° lateral pipe insertion angle. The paper shows that such insertion angle significantly improves the mixing quality in a T-joint. For a T-joint with D₂ / D₁ = 1, the length of the main pipe additional fragments (technically smooth, Ra40 roughness) were determined, ensuring the required gas mixture composition homogeneity and temperature

The work was carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation within the framework of State Task no. FSWF-2023-0017 (agreement no. 075-03-2023-383 from 01/18/2023) in the field of scientific activity for 2023--2025

Please cite this article in English as:

Tuponosov F.V., Artemov V.I., Yankov G.G., et al. Numerical analysis of efficiency of mixing the fuel gases in a T-joint with the lateral pipe diameter and its insertion angle alteration. Herald of the Bauman Moscow State Technical University, Series Natural Sciences, 2024, no. 3 (114), pp. 115--132 (in Russ.). EDN: SEFVZP

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