In this paper, the numerical study of cold flow over two types of regular and wavy V-gutter flame holders has been presented. The edges of the V-gutter, which are smooth in the regular case, are shaped in a sinusoidal form with different phase angles on upper and lower edges. The three-dimensional numerical analysis has been performed using the finite volume method and the renormalization group k–ɛ model has been used for turbulence modeling. The results were compared and validated by an existing experimental work based on the particle image velocimetry method. This study provided the fluid flow structure behind the V-gutter, the dimensions of the recirculation region, the behavior of vortex shedding phenomenon, and the static pressure distribution in the wake area. According to the results, the recirculation length for the sinusoidal case with 90 ° of the phase difference is the largest compared with the other cases, which increases the mass flow rate of the fresh unburnt mixture into the recirculation region and improves flame stability. The results also show that the 90 ° wavy V-gutter case has the lowest pressure drop in the wake region, which reduces the drag coefficient against the main flow. The values of the Strouhal number are approximately the same and equal to 0.27 for both cases (the regular and the 90 ° cases). Therefore, it is concluded that the 90 ° wavy V-gutter shows better performance than the regular V-gutter in flame stabilization.
Time-Dependent Material Properties of Shotcrete: Experimental and Numerical Study
