A uni ed hypersonic -supersonic lifting surface method has been developed, where the concept of piston theory is generalized and suitably integrated with the aerodynamic in uence coef cient (AIC) matrix due to linear theory. Thus, this uni ed method can account for the effects of wing thickness and/or ow incidence, upstream in uence, and three dimensionality for an arbitrary lifting surface system in an unsteady ow, whereas piston theory fails to account for the latter effects. In particular, the present composite series renders the AIC matrix uniformly valid for all supersonic -hypersonic Mach numbers, thus extending the method applicability to cover both the Ackeret limit at the low supersonic end and the Newtonian limit at the hypersonic end. From various cases studied it is concluded that the present method makes a substantial improvement over the linear lifting surface theory and piston theory in terms of unsteady pressures, stability derivatives, and utter speeds. Among other theories it also predicts the most conservative utter boundary and it con rms that the supersonic thickness effect is to reduce the utter speed.

A model for coupled dynamics of an airframe-propulsion integrated hypersonic airbreathing flight vehicle with various engine safety boundaries, called HIT-HAV (Harbin Institute of Technology), was developed to analyse the couplings among flight dynamics, aerodynamics, propulsion, and control. These engine safety boundaries included inlet unstart boundary, burner wall temperature limitation, burner lean fuel combustion boundary, rich fuel combustion boundary, and so on. All these engine safety boundaries were considered in modelling the HIT-HAV. The validity and practicability of the model were verified by comparing with a full-scale generic hypersonic vehicle. By simulating the HIT-HAV model, the conclusion was drawn that due to the couplings among flight dynamics, aerodynamics, propulsion, and control, the airframepropulsion integrated hypersonic air-breathing flight vehicle may operate, beside the normal operation mode, near some safety boundaries and may even exceed them, which may cause a failure flight. A hypersonic air-breathing flight vehicle's un-safety operation mode could be avoided by limiting the fuel supply, which has been verified in simulations. This paper indicates that for an airframe-propulsion integrated hypersonic air-breathing flight vehicle with various engine safety boundaries, as there were various relevant operation modes requested by various engine safety boundaries, an independent flight control and propulsion control in the traditional sense would fail to satisfy the hypersonic air-breathing flight and hence a multi-mode control design should be the focus of future research.

Low hemolysis is an important factor for axial blood pumps that has been used in patients with heart failure. The structure of impellers plays a key role in the hemolytic properties of axial blood pumps. Axial blood pumps with various structure impellers exhibit different hemolytic characteristic. In the present study, we aimed to investigate the type of impellers structures in axial blood pumps that contain the best low hemolytic properties. Also, it is expensive and time-consuming to validate the axial blood pump's hemolytic property by in vivo experiments. Therefore, in the present study, the numerical method was applied to analyze the hemolytic property in a blood pump. Specifically, the hemolysis of the pump was calculated by using a forward Euler approach based on the changes in shear stress and related exposure times along the particle trace lines. The different vane structures and rotational speed that affect hemolysis were analyzed and compared. The results showed that long–short alternant vanes exhibited the best hemolytic property which could be utilized in the optimization design of axial blood pumps.

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