| Boundary-Layer Separation |

| | Since the velocity in the **boundary** **layer** drops towards the wall, the kinetic energy of fluid particles inside the **boundary** **layer** appears to be less than that at the outer edge of the **boundary** **layer**, in fact the closer a fluid particle is to the wall the smaller appears to be its kinetic energy. |

| | The secondary shock is provoked by the thickening of the **boundary** **layer** which, in its turn, is caused by propagation of disturbances through the **boundary** **layer** from the region of higher pressure downstream of the main shock. |

| | It does not produce any noticeable contribution to the displacement effect of the **boundary** **layer**, which means that all the stream lines in the middle tier are parallel to each other and carry the deformation produced by the displacement effect of the viscous sublayer. |

| www.maths.manchester.ac.uk /~ruban/blsep.html (1923 words) |