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P. Liu
the aircraft, which will form shock wave outside the boundary layer
around the body. The interaction between shock wave and boundary layer
almost exists in the transonic or supersonic flow. It involves the stability
of compressible flow, transition, separation, shock oscillation, and turbulence pulsation, as well as the correlation among vortex, wave, and flow.
Especially in recent years, with the development of transonic and supersonic vehicle research, the mechanism of compressible boundary layer
transition and separation caused by shock wave and boundary layer interference has been paid more and more attention, because they directly
affect the resistance, surface thermal protection, and flight performance
of the vehicle.
As we all know, in 1904, Professor Ludwig Prandtl (1875–1953), the
famous German hydrologist, first studied the flow problem affected by
viscosity in the thin layer near the wall at low speed, put forward the
famous boundary layer theory, and explained the mechanism of resistance generation and heat exchange around the flow object physically,
which made it a widely used and studied theory. The study on the interaction between shock waves and compressible boundary layer flow was
first carried out by Liepmann H.W. in 1946 and Jakob Ackeret (1898–
1981), the Swiss aerodynamics scientist, in 1947. After that, it developed
slowly. But with the advent of supersonic vehicles, people begin to pay
more attention to this problem. Especially in the past ten years, driven
by the development of supersonic vehicles, transonic transporters, and
reusable space–time hypersonic vehicles, with the rapid development of
computational and experimental hydrodynamics, the research of supersonic compressible boundary layer flow and shock wave interference has
been pushed to a new climax. Based on different Reynolds numbers, there
are laminar and turbulent flow states in the boundary layer, which have
different effects on the wall friction resistance and heat transfer performance. If there is an interaction between shock wave and compressible
boundary layer, the flow in the boundary layer will be more complex,
and complex flow problems such as laminar flow, transition, turbulence,
separation, and reattachment may occur (as shown in Fig. 2.93), which
will seriously affect lift, resistance, and surface thermal protection of the
aircraft.
2. The interaction between normal shock wave and laminar boundary
layer
It has been known that the presence of a positive shock in the supersonic flow will reduce the Mach number of the main flow to the subsonic
value, which is accompanied by a rapid increase in pressure, density, and
P. Liu
the aircraft, which will form shock wave outside the boundary layer
around the body. The interaction between shock wave and boundary layer
almost exists in the transonic or supersonic flow. It involves the stability
of compressible flow, transition, separation, shock oscillation, and turbulence pulsation, as well as the correlation among vortex, wave, and flow.
Especially in recent years, with the development of transonic and supersonic vehicle research, the mechanism of compressible boundary layer
transition and separation caused by shock wave and boundary layer interference has been paid more and more attention, because they directly
affect the resistance, surface thermal protection, and flight performance
of the vehicle.
As we all know, in 1904, Professor Ludwig Prandtl (1875–1953), the
famous German hydrologist, first studied the flow problem affected by
viscosity in the thin layer near the wall at low speed, put forward the
famous boundary layer theory, and explained the mechanism of resistance generation and heat exchange around the flow object physically,
which made it a widely used and studied theory. The study on the interaction between shock waves and compressible boundary layer flow was
first carried out by Liepmann H.W. in 1946 and Jakob Ackeret (1898–
1981), the Swiss aerodynamics scientist, in 1947. After that, it developed
slowly. But with the advent of supersonic vehicles, people begin to pay
more attention to this problem. Especially in the past ten years, driven
by the development of supersonic vehicles, transonic transporters, and
reusable space–time hypersonic vehicles, with the rapid development of
computational and experimental hydrodynamics, the research of supersonic compressible boundary layer flow and shock wave interference has
been pushed to a new climax. Based on different Reynolds numbers, there
are laminar and turbulent flow states in the boundary layer, which have
different effects on the wall friction resistance and heat transfer performance. If there is an interaction between shock wave and compressible
boundary layer, the flow in the boundary layer will be more complex,
and complex flow problems such as laminar flow, transition, turbulence,
separation, and reattachment may occur (as shown in Fig. 2.93), which
will seriously affect lift, resistance, and surface thermal protection of the
aircraft.
2. The interaction between normal shock wave and laminar boundary
layer
It has been known that the presence of a positive shock in the supersonic flow will reduce the Mach number of the main flow to the subsonic
value, which is accompanied by a rapid increase in pressure, density, and