This paper presents a 0.25-scale quasi-three-dimensional hydraulic model experiment of transient fluid flow phenomena during continuous casting of steel under solidification. Water cooling is performed at the bottom of the mold, and saturated sodium acetate solution is covered on the spring and particle arrangement at the bottom of the mold/on the dummy bar to simulate the solidification phenomenon in the actual continuous casting process. The results show that the solidification on the dummy bar surface is very important to the early stage of the filling process and cannot be ignored. Its influence gradually decreases with the rise of the liquid level, and basically disappears when the liquid level rises to a certain height (steady liquid level, SLL). In SLL, the interface morphology of the solidified layer is more affected by the flow, while the interface morphology of the solidified layer has no significant effect on the liquid surface velocity.

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This paper presents a 0.25 scale quasi-three-dimensional hydraulic model experiment of transient fluid flow phenomena during continuous casting of steel. The relationship between the continuous casting process and the hydraulic jump phenomenon is established. The casting process in the mold is divided into four stages (I–IV) from the beginning to the end of continuous casting. The filling process involves stages I–II and is investigated by high-speed camera. The filling process is part of the cast start. In this paper, the hydraulic jump behavior varies and is controlled by different spring and iron chips arrangement on the dummy bar during the filling process. A filling coefficient is proposed to judge the best filling conditions and apply them to the whole filling process. There is an optimal spring and iron chip arrangement, which can adjust the hydraulic jump to optimize the initial flow field during the filling process, even the whole continuous casting process.

Strut/wall combined fuel injection scheme was adopted to improve mixing and combustion efficiency in a scramjet combustor fueled with liquid kerosene in the condition of Mach 6. Injectors were placed on the front of the strut and the side wall of the combustor. A series of numerical simulations and experiments were carried out to improve the combustor performance under conditions of different incoming flow velocity, injection methods and fuel distribution ratios. The value of pressure was obtained by pressure sensor and the flame images were captured by the high-speed camera in experiment. By processing and analyzing the basic data, characteristics of fuel mixing and combustion performance were discussed in this paper. Then, the influence mechanism of the strut/wall combined injection on the performance of the combustor was explained based on the performance with influence factors. Results indicated that the mixing and combustion efficiency was related to condition, injection method and nozzle arrangement. The strut/wall combined injection dispersed the heat release, which could reduce the pressure rise and total temperature. The fuel distribution ratio between the strut injection and wall injection is also a key factor affecting the performance of the combustor. These results in this paper are valuable for the combustion organization in the supersonic combustor and the improvement of the combustor performance.