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In order to find out the relationship between flotation process and energy input, the flotation tests were optimized by increasing input power in the flotation process. The drive motor speeds were 1 500, 1 800, 2 100, 2 400 and 2 700 r/min at different flotation periods. The flotation process was separated into five flotation periods of 0.5, 0.5, 1.0, 1.0, 2.0 min. The power dissipation in the flotation process was measured by energy measurement system. The flotation results show that the flotation rate, combustible matter recovery and accumulated ash content of clean coal increases with the increasing of rotate speed in the primary stage of flotation process. The combustible matter recovery is low while the quality of clean coal is high in the case of low energy input. The accumulated ash content of clean coal is the lowest and combustible matter recovery is higher while the drive motor speeds are 1 500, 1 500, 1 500, 1 500 and 2 400 r/min at the five flotation periods, respectively. The clean coal with higher combustible matter recovery and quality can be obtained while energy input is lower at the early stage of flotation process and higher at the later stage of flotation process in the case of same or similar total energy input. [ABSTRACT FROM AUTHOR]

The experimental investigation of blockerless cascade thrust reverser based on secondary injection was conducted on the dual flow transonic and supersonic cascade test facility. Effect of parameters including fan outlet pressure ratios, secondary pressure ratios, secondary injection positions and secondray injection angles on the performance of blockerless cascade thrust resver were studied. The final results show that fan outlet pressure ratios and secondary pressure ratios has some complex relationship. When secondary pressure ratio less than a certain value, cascase reverse mass flow decreases with the increase of fan outlet pressure ratio, however if secondary pressure ratio esceed the value, it would present a opposite trend. In the whole experimental conditions, there exist a best secondary injection position (58.77 mm ≤ Xj ≤ 77.87mmgle (θ - 60°) achieving highest thrust reverse. [ABSTRACT FROM AUTHOR]

Jet attachment is a critical restriction for the usage of counter-flow thrust vectoring nozzle, which will lead to the control invalidation of vector thrust. Therefore more attention should be paid to jet attachment phenomenon and detachment control. Based on CFD technology, the jet attachment mechanism, characteristic and forming course were investigated, and two methods for jet detachment were proposed. One is to increase suction pressure, and the other is to enhance nozzle pressure ratio(NPR). The results show that jet detachment would be successfully achieved by implement of suction pressure and NPR control. However, hysteresis phenomenon existed in the suction pressure control course. The jet attachment suction pressure was 60.68kPa, while detachment pressure 65.86kPa. [ABSTRACT FROM AUTHOR]