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The incident shock wave/turbulent boundary layer interactions (SWTBLIs) over a wide range of flow conditions are predicted by the Reynolds-averaged Navier–Stokes (RANS) numerical method to generate detailed two-dimensional steady flow field data. After examining the momentum balance terms over the control volume involving the separation bubble, it is concluded that the values of the pressure-force and the momentum-rate terms are significantly higher than the total stress-force term. Ignoring the effect of those small terms on the control surface, a model for the prediction of SWTBLI separation bubble scale is proposed based on the momentum balance over the two-dimensional control volume. For model prediction, essential correlations for key characteristic physical quantities are given. The predicted normal and streamwise scales of the SWTBLI separation bubble are in good agreement with the experimental results in the literatures. [ABSTRACT FROM AUTHOR]

• The incident SWTBLI flow in the presence of the expansion fan is studied. • The patterns and mechanisms by which the interaction zone is affected by the expansion fan are analyzed. • A scale-prediction method for incident SWTBLIs under the effect of the expansion fan is proposed. • Published experimental results and high-precision simulation results are employed to verify the accuracy of the prediction method. In this paper, the incident shock wave/turbulent boundary layer interaction (SWTBLI) in the presence of an expansion corner is investigated by numerical simulations. With the emphasis on the influence mechanism of the expansion fan for the interaction scale, the effects of the expansion corner angle and the relative positions between the shock impinging point and the expansion corner on the flow field structure and the distributions of the wall pressure and the wall friction coefficient in the interaction zone are discussed respectively. The study has found that as the expansion corner is located downstream of the shock impinging point and the expansion corner angle is larger than the incident shock deflection angle, the scale of the interaction zone is only related to the relative position between the expansion corner and the shock impinging point, and is not affected by the expansion corner angle. A scale-prediction method is proposed for the interaction flow under this flow condition. Considering the effect of the expansion fan as a weakening of the intensity of the incident shock, the corrected incident shock deflection angle under the effect of the expansion fan is defined. Then based on the results of the wide-range numerical simulations, the fitting equation of the corrected incident shock deflection angle is determined. Finally, according to the corrected shock deflection angle and the classical scaling method of SWTBLIs, the scale of the interaction zone influenced by the expansion fan can be solved. Published experimental results and high-precision simulation results are employed to verify the accuracy of the prediction method proposed in this paper. [ABSTRACT FROM AUTHOR]

A computational tool for quick estimation of mass-averaged throat performance for 2D ramjet inlets is presented. Based on the method of characteristics, coupled with unique corrections to the viscous flow and shock interactions associated with ramjet inlets, accurate predictions for the inlet throat are achieved. In comparison to viscous computational fluid dynamics simulation results, the absolute error for this rapid predictive tool is less than 3.5% over the working range of typical ramjet inlets, where the free-stream Mach number ranges from 2.2 to 4.0; the relative throat height ranges from 0.12 to 0.20, and the free-stream Reynolds number ranges from 3.20E+5 to 1.25E+7. [ABSTRACT FROM AUTHOR]

Due to the viscous effects, the inviscid Kantrowitz theory can not accurately predict the self-starting Mach number of supersonic inlets. A three-layer model is used to describe the main features of the flowfield in the critical state of two-dimensional (2D) supersonic inlets during self-starting, i.e. normal shock wave/boundary layer interaction. A method for predicting the self-starting limit of two-dimensional supersonic inlets is established, which is validated by unsteady numerical simulations. Compared to the CFD results, the predicted self-starting Mach number of two-dimensional supersonic inlets is much more accurate than that of the Kantrowitz theory. The present research is of importance for both design and operation of supersonic inlets. [ABSTRACT FROM AUTHOR]

Abstract: One-pot synthesis of novel phosphoramidates with porphine and nitrogenous drug was accomplished. In the absence of light, MTT test showed that they killed the BEL-7402 liver cancer cells effectively in vitro. The cell viability studied on normal liver and cancer cells showed that porphine phosphoramidates selectively kill the cancer cells, which was in sharp contrast with the non-porphine containing compound 4-formylphenyl N,N-bis(2-chloroethyl)-phosphoramidate. These results, coupled with the cell uptake test showing that they could differentiate the tumor cells from the normal cells by their selective accumulation in cancer cells, gave strong support to the notion that the introduction of porphine moiety in these molecules was responsible for the effectiveness and cell differentiability of these porphine phosphoramidates. [Copyright &y& Elsevier]

It is of great significance to study the hysteresis phenomenon in the unstart/restart process of supersonic inlets for restart control in the practical operation of ramjet engines. In this paper, the unsteady numerical simulations are conducted for the unstart/restart processes of a ramjet engine with a two-dimensional twin-duct inlet configuration under asymmetric incoming-flow conditions (M a 0 = 2.6,β = 2°), and the unstart/restart characteristics of the inlet caused by the plug throttling and the thermal choking are compared and analyzed. The results show that from the perspective of source incentives, the hysteresis loop of the restart process of the leeward inlet caused by the thermal choking is larger than that of the restart process of the leeward inlet caused by the plug throttling, which indicates that it is difficult to verify the restart performance of the ramjet with the two-dimensional twin-duct inlet configuration in the actual operating process by the inlet's plug-throttling experiment in the conventional wind tunnel. In addition, in the practical operations, the increase of fuel gas causes the transition of the leeward inlet to the unstart state, and part of the fuel gas reacts and combusts stably on the external compression surface of the leeward inlet, which easily leads to the burning of the inlet if there is without any special thermal protection. [ABSTRACT FROM AUTHOR]