partial vacuum
Noun
Meaning
partial vacuum (plural partial vacuums)
A region of low atmospheric pressure, especially one in which most of the air has been pumped out.
Examples
A partial vacuum, or rough vacuum, can be created using a positive displacement pump that transports a gas load from an inlet port to an outlet (exhaust) port.
Larger models, which can store over 200 litres (53 US gallons), are often hooked up to compressed air, utilizing the Venturi effect to produce a partial vacuum.
Experiments are being performed on the Avogadro Project's silicon spheres to determine whether their masses are most stable when stored in a vacuum, a partial vacuum, or ambient pressure.
Further damage can result as the gases cool and pressure drops sharply, leading to a partial vacuum.
Industrial Revolution Boulton & Watt engine of 1788 The Watt steam engine was the first type of steam engine to make use of steam at a pressure just above atmospheric to drive the piston helped by a partial vacuum.
It was the first type of steam engine to make use of steam at a pressure just above atmospheric to drive the piston helped by a partial vacuum.