SearcharxivSearch

arXiv subjects

David Jonsson

Publications and source records attributed to David Jonsson.

3 recordsLinked to original sources

Thermal pseudo stress in rotating matter

Thermal molecular motion in an accelerated coordinate system causes variety in pseudo forces and thus variety in pseudo stress in rotating matter. Averaged Eötvös effects and Coriolis accelerations on molecular level become noticeable. The effect is here derived for gas but does also exist in liquids, solid matter and plasma. In the atmosphere of Venus and Earth the pseudo shear stress is negligible and the vertical normal pseudo stress from Eötvös effects is lowered by 0.51 % and 0.27 % respectively. The shear stress component is not dependent on temperature and the normal stress component increases with the square root of the temperature.

physics.flu-dyn

Thermal torque in rotating gas

Molecular motion in combination with rotation causes a torque in gas when seen from a coordinate system fixed in the rotating system. The torque is caused by Coriolis forces.

astro-ph.EP

Shock minimized supersonic flight by heating

Bow shocks radiate a lot of energy away around supersonic objects in air. To minimize such waves is urgent for fast aircraft. Heat experiments exist where air drag is minimized. Here is a theoretical description of how shocks can be prevented by special distribution of heating.

physics.flu-dyn