Vacuum Pump - please explain?

A vacuum pump is an engine driven or electrical pump that provides a regulated flow of air used to spin a gyroscope. The gyroscope is used to stabilize instruments like the heading indicator and artificial horizon that are used in instrument navigation.

The section diagram for water (ignoring very excessive pressures) with stress plotted vertically and temperature plotted horizontally looks very like an the other way up letter T tilted reasonably to the left and with the left part tilted more. Elements within the higher left facet symbolize stable and those within the higher proper side symbolize liquid. Gas is below. Now visualize a pattern of liquid water above the freezing point in a partially filled stout container with a connection to a vacuum pump. Earlier than the pump is began, the liquid component is in equilibrium with water vapor bodily above it (beneath in the phase diagram). For this reason the pattern is on the right hand department of the upside down T. The pump which gets rid of air and water vapor. The of the pattern strikes down the left branch to a scale down temperature on the grounds that there is not any external input of warmth to switch the water vapor that was pumped away. Once most of the air is long gone, the water evaporates extra swiftly and boils. When the pattern reaches the factor the place the three branches join, the triple factor, stable starts offevolved to type. As soon as removal of water vapor has eliminated all of the liquid, the approach will continue down the solid-vapor line (left facet of the upside down T) and "freeze drying" will take position. This explanation is far simpler with a snapshot in entrance of 1.

The Pilots Handbook of Aeronautical Knowledge is FREE online. Everything you need to know can be found there: http://www.faa.gov/library/manuals/aviation/pilot_... Your question is answered in the chapter on Flight Instruments. Go to Chapter 7, page 16 and start reading under the section titled "Sources of Power"