Numerical Simulation on the Effects of Laval Nozzle Geometry on Gas-Quenching High-Viscosity Slag
Taiyang Liu (Shandong University - Weihai, Shandong University - Qingdao)
Jiahao Zhang (Shandong University - Weihai, Shandong University - Qingdao)
Jingcai Chang (Shandong University - Qingdao, Shandong University - Weihai)
Yuke Li (TU Delft - Civil Engineering & Geosciences)
Zongqiang Li (Shandong Shenhua Shanda Energy Environment Co. ,Ltd.)
Fenghua Wei (Shandong University - Qingdao)
Peng Wang (Shandong University - Jinan)
Hongfei Wu (Shandong University - Qingdao)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
During gas quenching of high-viscosity molten steel slag, the geometry of Laval nozzles is critical for stabilizing the internal flow transition from supersonic to subsonic regimes, impacting both energy consumption and system safety. This study simulated four nozzle designs (rectangular, circular, cross-shaped, and triangular) to analyze their effects on shock-induced velocity fluctuations, internal flow efficiency, external flow fields, and slag fragmentation. All nozzles produced a deceleration–acceleration–deceleration flow pattern, but the triangular nozzle exhibited the earliest velocity peak, the largest fluctuation period distance, and the smallest low-speed region proportion (0.0141). Its triangular shape reduces flow separation, promotes smooth channel contraction, and minimizes pressure fluctuations, enhancing flow stability and energy efficiency. Externally, the triangular nozzle generated the highest-velocity jet with the lowest frequency of expansion/compression waves. Under the impact of this jet, the deformation increased linearly to 9.16, and a concave structure with a thin center and two thick sides at the front end of the liquid slag column formed. Fragmented particles were finest, with volume and De Brouckere diameters of 0.625 mm and 0.695 mm, respectively. These findings provide mechanistic insight into gas-quenching fragmentation of high-viscosity molten slag.