【Daily Question】In-depth Processing 20160917 Short Answer: What is the principle of a vacuum extractor?
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To increase popularity and foster technical exchanges among sea enthusiasts, 【One Question per Day】 is hereby launched. Participation earns 4 points of wealth! 10 wealth points as a reward for correct answers or in-depth discussions! :Lol short answer question: How does a vacuum extractor work? By utilizing the “Venturi” principle, gas flows at high speed within the pipeline, passing through areas of reduced diameter followed by areas of increased diameter; this causes the pressure to drop while the speed increases, thereby creating a negative pressure or vacuum in the surrounding area. ======================================== ☛[Haichuan Activity Plan] I decide my own questions – I’ll choose the “best answer”! http://bbs.hcbbs.com/thread-1618021-1-1.html (Source: Haichuan Chemical Industry Forum)
1) High-pressure water vapor is used to convert pressure energy into kinetic energy through a nozzle, resulting in high-speed flow; this creates a vacuum around the nozzle exit, which draws in gas. 2) After the steam and the intake gas mix in the mixing chamber, their velocity decreases gradually in the diffuser chamber; this kinetic energy is then converted into pressure energy, resulting in the exhaust pressure being significantly higher than the pressure in the intake chamber
A steam-jet evacuator consists of a convergent-divergent nozzle, a diffuser tube, and a mixer. When steam enters the steam-jet pump, it first passes through an expansion nozzle; as the gas flows through this nozzle, its velocity increases while its pressure decreases, and a very high velocity can be achieved at the outlet of the nozzle. (1000–1400 meters per second). With very low pressure (\(700\)\) millimeters of mercury vacuum), a high vacuum is created around the nozzle.
Working principle； A steam-jet evacuator consists of a convergent-divergent nozzle, a diffuser tube, and a mixer. When steam enters the steam-jet pump, it first passes through an expansion nozzle; as the gas flows through this nozzle, its velocity increases while its pressure decreases, and a very high velocity can be achieved at the outlet of the nozzle. (1000–1400 meters per second). With very low pressure (\(700\)\) millimeters of mercury vacuum), a high vacuum is created around the nozzle. Non-condensable gases, water vapor, and oil vapor—are collectively referred to as the gases being drawn in. They are drawn in at the inlet, mixed with the driving steam in the mixing chamber, and then carried into the diffuser. At the front part of the diffuser, these two types of gas streams mix further and exchange energy. As the airflow passes through the diffuser, its kinetic energy is converted back into pressure energy; the flow velocity decreases while the pressure increases, and ultimately this increased pressure meets the requirements of the discharge pressure.
Negative pressure is created at the inlet due to the high-speed flow of the fluid, thereby achieving vacuum pumping
When steam enters the steam-jet pump, it first passes through an expansion nozzle; as the gas flows through this nozzle, its velocity increases while its pressure decreases, and a very high velocity can be achieved at the outlet of the nozzle.
I’m not sure which vacuum device this question is referring to. A gas pump operates based on Bernoulli’s equation for fluid flow: when the fluid velocity increases at the narrowest part of the pipeline due to the reduced cross-sectional area, the dynamic pressure increases while the static pressure decreases, thereby creating a vacuum effect. A water ring pump achieves suction, compression, and exhaust by changing the volume of its pumping chamber; therefore, it belongs to the category of variable-volume vacuum pumps.
The pump utilizes Bernoulli’s principle: the flow channel at the throat is narrow, resulting in high flow speeds and low pressure. As a result, fluid from areas of higher pressure flows to this area, thereby creating a low pressure inside the container or pipeline.
The working steam passes through the nozzle to achieve high velocity, thereby converting steam pressure energy into kinetic energy. It mixes with the gas drawn in at the mixing chamber, and after that, the mixture enters the diffuser chamber. In the diffuser chamber, the velocity gradually decreases, and the kinetic energy is converted back into pressure energy. This allows the mixed gas discharged by the pump to lower the pressure in the suction chamber. The compression ratio that each stage of the ejector can achieve, that is, the ratio of the discharge pressure (absolute pressure) to the suction pressure (absolute pressure), has certain operational limits.