What is a shock tube?
The shock tube is a tool used to study reactions of the gas phase and aerodynamic flow. Its simplest is a shock tube with a metal tube with a membrane, partly a flexible barrier, which separates high -pressure gas from low -pressure gas. To start the experiment, the membrane is cracked, causing the shock wave to pass through low -pressure gas. The gases may not be the same chemical composition. The belts are pumped to or from the tube on each side of the membrane until the required pressure is reached on each side. To start the experiment with the shock tube, the membrane can be cracked using a piston with connected blade, although the desired mechanism is complex. Many experiments either use a scoring membrane designed to burst when a certain pressure is reached, or use flammable gases in the driver tore the diaphragm.
When the membrane is cracked in the tube, it travels to the driveno Gas shock wave, sudden, spreading interference. The temperature and pressure of the powered gas also increases and the shock wave causes aerodynamic flow in the direction of shock wave, but at a lower speed or speed. Promotional pressure drop, called rare waves or expansion fan, travels back to the driver's gas. The contact surface, the boundary between the driver and the throttle gas, travels to the driven gas, just behind the impact front and defines the shock wave limit.
When the shock wave reaches the end of the tube, it reflects, travels back to the driver's gas and causes an even greater increase in temperature, pressure and density. The use of a tank landfill to absorb a reflected shock wave can prevent this reaction. After the shock wave was created, the gas in the shock tube is removed and studied to observe the effects of high pressure and temperature. The width tube can also be used to study the effects of burning on solid particles, which are inserted into the tube before the membrane rupture.
width tube can beKé use to study aerodynamic flow of powered gas behind the shock wave. The combustion occurs very quickly. The result is a limited time to observe the aerodynamic flow, usually only a few milliseconds.