Aphornratanaan experimental investigation of a steam ejector refrigerator. Steam ejector calculation posted in industrial professionals. Steam ejectors and deaerators custom engineered products the end product of the process and mechanical design expertise of hick hargreaves combined with project management skills is the perfect supply of individual items of plant, or the execution of complete fully systemized equipment packages. Hence it is relatively lowcost and easy to operate and maintenance free equipment. Previous 1d analytical models can be derived from this new. Steam jet vacuum ejectors remove gases andor vapours from process operations thereby generating a vacuum in the reactor. An ejector operation in the critical range is designed for a fixed compression ratio and requires a definite motive steam flow. Ejector calculations require cpcv values for each gas. Steam locomotives, with a ready source of steam, found ejector technology ideal with its rugged simplicity and lack of moving parts. Northvale korting fluid jet theory and applications of eductors by patrick belcher eductor basics. Mar 06, 2018 the programs may be used for any liquid for which the physical properties are known. The programs may be used for any liquid for which the physical properties are known. They can operate with either incompressible or compressible fluids as the primary driving and secondary driven flows.
A steam injector is typically used to deliver cold water to a boiler against its own pressure, using its own live or exhaust steam, replacing any mechanical pump. For example, a high vacuum exhauster operating at 150 psig steam pressure compressing from 1 hg. The steam ejector has four component parts, a nozzle holder, a steam nozzle, steam chest and a diffuser. Because eductors are nonmechanical, they do not include moving parts or require lubrication.
Ejectors and eductors selection guide engineering360. Ejector design software ejector sizing calculation. High pressure motive steam at pressure p 0a expands through a nozzle and exits at low pressure and at high velocity. Steam ejector design chemical process engineering engtips. Free demo programs for a short time are offered to let you see how the ejector program works they are not intended for your design work. Boundaries of the application field of this procedure are revealed.
As an experienced provider of engineering answers since 1936, graham maintains the most comprehensive database of. Convergence percent normally 99% is supplied to confirm. Ejector design software to do conceptual design and generate ejector sizes. With cd ejector you can customize how you want to operate your drives, suit it to your laptop. The ejector design principles used in the ejector calculations for the program are explained including the ejector energy balance and effects of the ejector flow cones free demo programs for a short time are offered to let you see how the ejector program works they are not. An ejector is intended to move high gascut fluids and has a convergent section for an entry to the straight throat which is again followed by a divergent section. The same ejector can be made to operate with essentially. A new approach for determining the main parameters of an ejector is proposed, and a sequence for calculating it is given. Ejector design calculation, ejector dimensions, generate. They were initially used to eject air from condensing plants on turbine systems. You are able to select up to a fourstage ejector system, with or without a precondenser, that includes either surface type or direct contact inter and after condensers.
A method for prediction of gasgas ejector performance. Review of ejector design parameters and geometry for refrigeration and. The stainless steel sump ejector uses a snapacting inconel x750 springassisted mechanism, which engages a steam motive valve, turning the pump on or off as the float rises and falls. Directx, games for windows live redist, vc redist, rapture3d, nvidia physx redist, etc. They were installed from the cddvd, and those installers didnt stay on your hard drive. In condesing system, steam ejector has function to extract air and other noncondensing gases from the sealed condenser, and in such way to maintain vacuum which corresponds to ratio of. Other types of injector may use other pressurised motive. It consists of an objectoriented server connected to a database, and web, java, and other ftp, smtp, irc, etc. The nozzle provides controlled expansion of the motive steam to convert pressure in to velocity which creates a vacuum with in the body chamber to draw in and entrain gases or vapours. Hi, i need a help for expert in this process engineering side. Eductors are used to lift, pump, mix, and agitate liquids, granular solids, and slurries.
Exhaustive survey has been conducted on the influence of geometrical parameters on the efficiency of the ejector as well as critical flow parameters to improve the overall performance. Vacworks ii is a selection software suite developed by graham engineers that enables you to select ejector systems or ejectors in combination with liquid ring vacuum pumps. At the higher discharge pressure, the ejector will regain its stability once the motive steam. Steam ejectors are virtually maintenancefree and can be constructed from a wide variety of steel, alloy and composite materials to include pp, ptfe and pvdf. The methodology for ejector design and for the hp active gas is accelerated to sonic velocity in the throat of the ejector inlet nozzle prediction of performance, based on the. This reduces the size and steam consumption of the succeeding stages and results in a reprinted from petroleum refiner, december 1958 1 ejectors ejectors are simple pieces of. The ejector design principles used in the ejector calculations for the program are explained including the ejector energy balance and effects of the ejector flow cones. Actually, i need the ejector to maintain the vacuum in the condenser of a steam turbine power plant and the turbine exhaust pressure is 9. Steam ejectors are frequently used in condensing steam turbine systems for creation of vacuum in vacuum condesers thus improving turbine and system performance. Steam can be used as the motive fluid in either case. Steam jet ejectors, the largest vacuum producing device.
Evaluation of steam jet ejectors linkedin slideshare. When you installed a video game from a cd or a dvd, you installed some redistributable packages too. A steam injector is a device whereby steam is used to pump cold water at low pressure and to produce an outlet water pressure which is higher than the steam inlet pressure. In ejector simulation computing, physical features in clude cross ejector throat and nozzle exit cross section and constant level of ejectors and operational levels, including the stimulus temperature and. A free cpcv calculator for gas mixtures ideal gas can be downloaded here. As a result the roofs have some unique hatches often erroneously called ice hatches.
Ejector design calculation pdf download 08d661c4be this content was downloaded from ip address 66. This system have problem of droping vacuum and the tempearture of water circulation for ejector incraseaese rapidly desite the cooling. An ejector is a device used to suck the gas or vapour from the desired vessel or system. I need to calculate how much vacuum pressure created if i used 15 barg steam pressure in steam ejector. Applied vacuum designs and manufactures steam jet ejectors for the sugar industry. The low pressure induces a flow of load vapours at the suction pressure p 0b into the ejector. Ejector modeling and examining of possibility of replacing. The motive gas mach no is provided for information. A jet ejector requires no mechanical drive and has no moving parts. The pickup pressure is a direct function of the discharge pressure. Review on ejector efficiencies in various ejector systems. Calculation of the constant pressure mixing process between sections 3 general assumptions and model equations, 4 ejector design. A 4 see assumptions a11 and a12 the momentum equation for this control volume is considerably simplified and yields.
Best a generalized ejector model was successfully developed for gas ejector design and performance analysis. A study was performed to establish a simpler primary flow active gas through nozzle. How to calculate the mass flow rate of induced secondary. A single ejector can be designed to create as much as 27 inches hg vacuum or about 76 mm hga.
They are especially effective in the chemical industry where an onsite supply of steam ejector calculation free download, steam ejector design software, steam. The problem usually involved hardness deposits in the throat of the weaker ejector steam nozzle. Chemical engineering and processing 41 2002 551561 evaluation of steam jet ejectors hisham eldessouky, hisham ettouney, imad alatiqi, ghada alnuwaibit department of chemical engineering, college of engineering and petroleum, kuwait uni6ersity, p. Calculation of the constant pressure mixing process between sections 3 general assumptions and model equations, 4. With cdejector you can customize how you want to operate your drives, suit it to your laptop. Ejector systems ejectors gea engineering for a better world. The major difference between the ejector and the vacuum pump or compressor is it had no moving parts. The main goal of the simulation of ejector is calculation of driving steam consumption rate. Ejector design and performance prediction sciencedirect. Basic ejector components are the steam chest, nozzle, suction, throat, diffuser and they discharge fig. In multistage ejectors, it is usually advantageous to condense the steam from each stage in a watercooled intercondenser so as to reduce the load to the succeeding stage. The system has also been erroneously called steam injector.
Because eductors are nonmechanical, they do not include moving parts or require. How to calculate the flowrate of motive fluid in an ejector free download as pdf file. When first developed, its operation was intriguing because it seemed paradoxical, almost like perpetual motion, but it was later explained using thermodynamics. Stainless steel sump ejector armstrong international. Steam ejector freeware free download steam ejector. Through the acquisition of hick hargreaves in 2001 edwards have been instrumental in the development of steam ejectors from the original crude single stage devices to the highly efficient multi stage. An ejector is similar to an of vacuum pump or compressor. A variety of air conditioning systems were used by american railroads, and santa fe settled on steam ejector air conditioning for the majority of its cars. The system have a water ejector followed by three steam booster. The steam ejector takes a high pressure motive steam flows in a supersonic nozzle while dragging a low pressure steam which comes from the. Ejector working principle mechanical engineering site. Ejectors, or jet pumps, utilize the pressure energy of a highpressure fluid stream to boost the pressure andor flow of a lowpressure source.
If the steam pressure is being increased from a region of unstabile operation, the point at which the ejector first becomes stable is called the motive steam pickup pressure. Steam ejector software free download steam ejector. Dear art montemayor hi i am currently working on existing vacuum system in my plant. The steam ejector takes a high pressure motive steam flows in a supersonic nozzle while dragging a low pressure steam which comes from the crossover. The efficiency of the ejector cycle is very sensitive to the ejector efficiency. Steam jet ejectors steam jet ejectors are based on the ejector venturi principal and operate by passing motive steam through an expanding nozzle. When a high pressure motive fluid steam liquid enters the steam nozzle, this result in a decreasing pressure and increasing velocity of the fluid again the fluid enters in the diffuser which result in a increasing pressure and decreasing velocity of the fluid so due to pressure difference vacuum is created in between the nozzle and diffuser we can say venture.
They are sometimes called aspirators, venturi pumps, or jet pump ejectors. In ejector simulation computing, physical features in clude cross ejector throat and nozzle exit cross section and constant level of ejectors and operational levels, including the. Cpcv calculator ejector design software ejector sizing. Featuring proven, unique internal geometries and tightly tolerancecontrolled steam nozzle configurations, graham ejectors produce very low steam consumption and highly efficient operation. This basic principle applies to every jet ejector in different models and ranges of application. Steam ejector calculation industrial professionals.
The equations of the constantpressure and constantarea models were verified. The main features of an ejector are shown in figure 1. A procedure for calculating gas ejectors springerlink. Its main characteristic is that no moving parts are needed for its functioning, thermodynamic processes relying on direct transfers of mass, momentum and heat between the. A steam jet ejector is illustrated below as example steam serves as motive fluid to create vacuum.
Steam flow from the discharge of the stronger ejector flowed backwards through the weaker ejector into the suction of the stronger ejector, which was then overloaded. Ejector design calculation pdf download unger i hedmark l. Performance optimization of steam jet ejector using cfd. The application determines the design of the flow section. The suction flow is compressed to a higher pressure. Armstrong offers a stainless steel sump ejector for use in draining unwanted water from steam pits, steam tunnels or enclosed spaces. You can also get wet steam into an ejector and this will cause back firing on the ejector also putting material back into process. The applicable equations are provided by huang et al 1, 2 as follows. Ejector design calculation pdf download anpsortigas. The best companion of steam users the good old time. The first steam ejectors were developed in the early 1900s. The basic principle of jet pumps consists in the liquid or gas jet being emitted by a nozzle at high speed entraining and accelerating the surrounding liquid, gas or solid matter.
Working principle of steam ejector power plant tutorials. The definitions of overall ejector efficiency and ejector component efficiencies in literature are. The reason for the lecture is that if you a trying to pump liquid you dont want to use and ejector velocities get pretty high. A temporary fix is to block in the process side of the weaker steam nozzle. If discharge side of ejector is blocked in and steam is not the steam is going to path of least resistance, back to process. Simplest procedure of spalding 15 in phoenics software, a general commercial cfd package. Aug, 2009 results obtained from an analysis of the most widespread and commonly used procedure for calculating gas ejectors equipped with a cylindrical mixing chamber are presented. Very often, the motive fluid is steam and the device is called a steam jet ejector. Relative suction flow of steam jet vacuum ejectors the result of calculation will be identical with the download fulltext pdf. Results obtained from an analysis of the most widespread and commonly used procedure for calculating gas ejectors equipped with a cylindrical mixing chamber are presented. To create a deeper vacuum, ejectors can be staged or installed in series. Steam ejectors or steam jets, ejectors that use steam as motive gas, are by far the most popular type of ejectors. A model for calculation of steam injector performance.
These are more indicative of the response of a specific ejector to changes in inputs. Case studysteam jet ejector free download as powerpoint presentation. Request for software from graham corporation graham. Ejector design software ejector sizing calculation ezejector.
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