What is the function of ejector?
The ejector uses a converging nozzle to increase the fluid velocity to transform high static pressure into velocity pressure. This conversion of static pressure to velocity pressure results in a low pressure zone that provides the motive force to entrain a side fluid.
What is ejector in steam turbine?
the Steam jet ejector are used for air removal on surface condensers. They are simple in operation and rugged in construction, can use a wide range of steam pressures, and will handle wet or dry mixtures of air, gases, or vapors at a near-perfect vacuum.
What is the function of vacuum ejector?
The purpose of the ejector is to transport and compress a weight of induced fluid from the suction pressure to the exit pressure. By staging ejectors it is possible to obtain a very large range of suction pressures from atmospheric down to as low as one micron of mercury absolute.
How does a Hogger work?
Hogger is a device that pulls out the air from the condenser with the aid of steam that is passed into it. The working principle involves the steam admission to the hogging ejector wherein the nozzle converts the steam pressure to velocity which pulls out the air from the condenser.
How vacuum is created in ejector?
In an ejector, a working fluid (liquid or gaseous) flows through a jet nozzle into a tube that first narrows and then expands in cross-sectional area. The fluid leaving the jet is flowing at a high velocity which due to Bernoulli’s principle results in it having low pressure, thus generating a vacuum.
Why steam is used in ejector?
In a jet or ejector, a relatively high-pressure gas, like steam or air, expands through a nozzle. The steam or air converts that pressure or potential energy to velocity or kinetic energy. The jet of high-velocity steam or gas entrains the gas to be evacuated or pumped in the suction of the ejector.
Why vacuum is required in steam turbine?
Vacuum applies to steam turbines because the pressure of saturated vapour above available cooling water is well below 1 bar (typically 17 mbar at 15°C ambient). These shortcomings are examined and used to explain the anomalous response of a turbine to a copious supply of cold winter cooling water.
How do I choose a vacuum ejector?
When choosing a vacuum pump, you must take into account several factors. First of all, your choice should be adapted to your intended use, this will allow you to determine the technology, lubrication, chemical resistance, vacuum level and necessary flow rate.
What is a Hogger system?
Hogger is a type of ejector mostly operating with medium pressure steam ranging between 5–15 barA as a motive fluid generally used to generate and occasionally maintain a vacuum in a condensing type steam turbine system.
How many types of ejectors are there?
Ejectors are generally categorized into one of four basic types: single-stage, multi-stage non-condensing, multi-stage condensing and multi-stage with both condensing and non-condensing stages. Single-stage ejectors are the simplest and most commonly used construction.
What does ejector mean?
1 : one that ejects especially : a mechanism of a firearm that ejects an empty cartridge. 2 : a jet pump for withdrawing a gas, fluid, or powdery substance from a space.
What is difference between ejector and eductor?
1. The eductors are used to remove the air 4 times the volume of the vessel per hour for the vessel entry jobs. whereas the ejectors just suck the excess volume of the system and maintains the system pressure accurately. The difference is with respect to their function and not with respect with their motive fluid.
How does the ejector in a steam turbine work?
As you know for steam turbine,gland condenser by means of a steam ejector and it is condensed by means of cooling fan. The condensate flows to a condensate recovery skid. In Our plant, we are using plant air (100PSIG) to creat a vaume inside the steam ejector.Now, for maintenance reason, we need to shutdown Plant air for full day.
What are steam jet air ejectors used for?
General: The attached figures illustrate the two types of Steam Jet Air Ejector (SJAE) systems used in the industry to remove non-condensables and water vapor from main condensers.
Why do you need an air ejector in a boiler?
The air ejector draws out the air and vapours which are released from the condensing steam in the condenser. If the air were not removed from the system it could cause corrosion problems in the boiler.
How does a steam ejector work in a diffuser?
The jet of high-velocity steam or gas entrains the gas to be evacuated or pumped in the suction of the ejector. The resulting mixture enters the diffuser where velocity energy is converted to pressure at the ejector discharge. Ejectors that use air as motive are often called air ejectors or air jets.
