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. A high pressure, motive, fluid usually steam enters the ejector chest through a nozzle and then expands. The system have a water ejector followed by three steam booster. For high compression ratios a long narrow diffuser is used, and for low compression ratios a shorter, wider design. Theoretical and experimental investigations of different area ratios of. Overview of ejector stage calculations a step by step approach to stage calculations selecting an approach to ejector steam usage calculations derivation and application of calculation methods how a liquid jet liquid ejector works. Steam jet ejectors educt process gases into the steam chest and then through a specially understand realworld problems of vacuum ejector performance use these guidelines and case histories to evaluate and troubleshoot. These two types of ejectors were tested in a steam jet refrigeration. Steam flow to an ejector must be maintained at the design rates, otherwise vacuum column operating pressure may increase.
Ejector design calculation pdf download crack autocad 2016. Review of ejector design parameters and geometry for refrigeration and. Combining low capital cost, simple operation, high reliability and the ability to handle large volumes at very high vacuum levels, they can be optimized to. You make these calculations and insert them in a steam jet ejector data sheet and submit it to a steam jet ejector manufacturer for an estimate and bid. Convergence percent normally 99% is supplied to confirm. When first developed, its operation was intriguing because it seemed paradoxical, almost like perpetual motion, but it was later explained using thermodynamics. Recent efforts in cooling and heating design optimization have identified ejectors as offering a great application potential but operational and design knowledge with fluids other than air or water, or off design operation assessment. Ejectors can be divided into two categories based on the type of performance. Our experience spans a wide range of applications and markets, including systems for space simulation, high vacuum applications in metals vacuum degassing, applications involving vaporliquid and chemical equilibrium for fertilizer plants, sophisticated process. Exhaustive survey has been conducted on the influence of. Privacy policy legal notice site map accessibility get adobe. This allows for full design of the ejector, where defining the ejector load.
Ejector design calculation pdf download anpsortigas. Ejector modeling and examining of possibility of replacing. Ejector design software ejector sizing calculation ezejector. 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. How to calculate motive steam pressure for steam jet air. Best a generalized ejector model was successfully developed for gas ejector design and performance analysis. Steam ejector calculation industrial professionals. A general simulation of an air ejector diffuser system. Aug 17, 2007 i would like to go from my design parameters, such as desired suction pressure and steam temperature and pressure to determine nozzle diameter, etc. Steamjet ejectors are pumping devices used, in general, to evacuate fluids gases and vapors from one process system step and deliver them to another.
In a steamjet ejector, the suction chamber is connected to the vessel or pipeline. This create a vacuum in a vessels or chamber to which ejector is connected. Simplified ejector model for control and optimization. Most ejectors have a fixed capacity curve as shown in figure 1. Steam jet ejectors are typically furnished in cast iron or steel with a nozzle of stainless steel. A general simulation of an air ejector diffuser system derick thomas daniel university of tennessee knoxville, derick. 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. In their study, they used polytropic efficiencies to represent the irreversibility of fluids during acceleration and deceleration. Relative suction flow of steam jet vacuum ejectors the result of calculation will be.
A simple example is the removal of air from a closed vessel and discharging it to the atmosphere. A method of calculation for the ejector design using the 210. Jul, 2016 graham has mastered steam ejector design. Can operate safely under the most hazardous conditions. Basic design, operating information, and operation limitations of air 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 stimulus temperature and. To submit a request for quote rfq for multistage steam jet ejectors, adobe pdf or submit an online interactive rfq form for steam jet vacuum systems. Steam jet ejectors are often used to pull vacuum on surface condensers, evaporators, etc.
Ejector configuration for designing a simple and high. Graham corporation brings more than 70 years of proven experience to the application, design, and operation of ejector systems. Steam ejectors provide vacuum in many process industries and utility companies. If the liquid is a waterbased slurry or solution, these. The process vapours are entrained by this steam jet and carry into a venturi shape diffuser, which convert the velocity energy of the steam into pressure energy enabling discharge ultimately to atmosphere.
Vacuum products steam jet ejectors by graham corporation. Steam jet ejectors for the process industries mcgrawhill. These power systems have found wide acceptance in modern plants because of the small space requirements, simplicity, reliability, low maintenance and quick starting. The primary advantages of steam jet ejector are simplicity of operation, no mechanical drive and has no moving parts. Steam jet ejectors are a simple alternative to mechanical pumps for vacuum raising applications. Condensing of motive steam greatly improves ejector set efficiency. The steem jet ejector has been manufactured in complete compliance with the industrial quality norms using superior grade metals and components. Ejectors will handle highly corrosive vapours and fluids. These ratios are computer calculated and are the key parameters in ejector design. Please provide us with some information about your vacuum application needs and we will provide you with a free quote to meet your specific requirements. Performance optimization of steam jet ejector using cfd. These are more indicative of the response of a specific ejector to changes in inputs. The function depends, above all, on the design of the motive nozzle 2 and of the. Featuring proven, unique internal geometries and tightly tolerancecontrolled steam nozzle configurations, graham ejectors produce very low steam.
Therefore ejector curves at fixed ejector geometry are calculated at the design discharge pressure and an increased discharge pressure see 3. Dear art montemayor hi i am currently working on existing vacuum system in my plant. 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. An ejector consists of a nozzle, a diffuser and a body, or mixing chamber, see fig. Increasing the steam pressure above the design pressure will not increase the capacity of the ejector. Steam jet ejector nozzle steam free 30day trial scribd. Steam jet ejector we are counted amongst the prestigious manufacturers and supplier of steam jet ejector in ankleshwar, gujarat, india. On the design and corresponding performance of steam jet. Thermodynamic analysis of steam ejector refrigeration cycle. Very often, the motive fluid is steam and the device is called a steam jet ejector. Steam jet ejectors are based on the ejectorventuri principle. Other types of injector may use other pressurised motive fluids such as air.
The first tsme international conference on mechanical engineering 2022 october, 2010, ubon ratchathanidesign of a steam ejector by co operating the esdu design method and cfd simulationchayarnon saengmanee1 and kulachate pianthong11 department of mechanical engineering, faculty of engineering, ubon ratchathani university, ubonratchathani, thailand 34190 corresponding. These power systems have found wide acceptance in modern plants because of the small space requirements, simplicity, reliability, low maintenance and quick starting characteristics. Retubeco will inspect and repair every component of your steam jet air ejector, detecting erosion, steam impingement, and tube failures. The motive gas mach no is provided for information.
Feasibility study of replacing steam ejector with liquid. The suction flow is compressed to a higher pressure. This system have problem of droping vacuum and the tempearture of water circulation for ejector incraseaese rapidly desite the cooling. Vacuum steam jet cooling systems jet pumps, mixers, preheaters multistage steam jet pumps are employed in the edible oil industry where the product is refined and freed of unwanted aromas by distillation under vacuum 15 mbar. In practice, for suction pressure below 100 mbar absolute, more than one ejector will be used, usually with condensers between the ejector stages. Hi, i need a help for expert in this process engineering side. Previous 1d analytical models can be derived from this new. Oct 22, 2016 ejector design very simply, an ejector is a pumping device. The design conditions for the ejector, determined in an earlier analysis of a meetvc multieffect evaporation with thermal vapour compression desalination system, are the following. How to size liquid motive eductors for pumping liquids. The best way to adjust for the specific gravity or temperature effects of the suction fluid is to do the calculation for npsh see page 5 of this manual. Design of a steam ejector by co operating the esdu.
The attached figures illustrate the two types of steam jet air ejector sjae systems used in the industry to remove noncondensables and water vapor from main condensers. The nozzle is designed to produce a jet at high velocity by expanding the motive fluid from inlet to suction pressure. Ejector design calculation, ejector dimensions, generate. Because an ejector itself is a key component in this cycle to get higher performance by. The first tsme international conference on mechanical engineering 2022 october, 2010, ubon ratchathanidesign of a steam ejector by co operating the esdu design method and cfd simulationchayarnon saengmanee1 and kulachate pianthong11 department of mechanical engineering, faculty of engineering, ubon ratchathani university, ubonratchathani, thailand 34190 corresponding author. The motive steam and the entrained vapour have the same molecular weight and specific heat ratio. A typical steam jet ejector system consistence of one or more steam ejector assemblies with associated ejector condensers arranged to condense vapor discharged from previous ejector stage assemblies. The nozzle discharges a high velocity steam ejector across a suction chamber that is connected to the equipment to be evacuated. How can i calculate the motive steam pressure of a steam.
A steam jet ejector is illustrated below as example steam serves as motive fluid to create vacuum. Nash has been designing, manufacturing and troubleshooting steam jet air ejector systems since 1986. Understand realworld problems of vacuum ejector performance. The ejector formed part of an experimental ejector cycle designed to be installed in a small motor vehicle to provide air. Review on ejector efficiencies in various ejector systems. I realize there are some existing ejector ratios that require only a throat diameter, with all other proportions of the ejector being determined from this value, such as the langhaar ejector.
Steam jet air ejectors are some of the most reliable vacuum creators, but they require proper tube maintenance and replacement of corroded or eroded tubes in order to function efficiently. Steam jetejectors educt process gases into the steam chest and then through a specially understand realworld problems of vacuum ejector performance use these guidelines and case histories to evaluate and troubleshoot. The steam ejector utilizes high pressure steam to compress low pressure vapors or gases. Graham corporation ejector efficient operation youtube. Jet ejectors the term jet ejector describes a device in which a pumping effect is achieved using a. Steam jet air ejectors air ejectors retubeco ooltewah, tn. Liquid jet mixers for food applicationsorbitally welded design. Jet ejectors, adobe pdf or submit an online interactive rfq form for steam jet. Threestage condensing steam jet ejectors consist of a booster ejector, a booster condenser, and a twostage ejector consisting of a highvacuum ejector, intercondenser, and low vacuum ejector. Steam ejector calculation posted in industrial professionals. The ejector flow is onedimensional and at steady state conditions. Introduction suction nozzle ejector has been widely used in different cycles for refrigeration purposes, such as recovery of expansion work, utilization of lowgrade energy solar energy, geothermal energy and waste heat. 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.
This paper describes the design of a steam jet ejector and its validation. The increased velocity causes reduced pressure, which sucks in and entrains gas from. They always helped me calculate steam ejector applications. It is one of the types of air ejector which is used in the steam like near the condenser to remove the noncondensable gases and some vapour entering into main condenser by an air ejector and it is cooled by the main condensate and released in the ejector condenser. You just might have to do conversions in the formulations to your application.
Based on the cfd results, it is observed that there is a room to perform design optimization of the ejector without affecting outlet conditions. The design of the nozzle varies depending upon expansion ratio, state of fluid and type of the ejector. The main goal of the simulation of ejector is calculation of driving steam consumption rate. Evaluation of steam jet ejectors linkedin slideshare. Mar 26, 2012 steam ejector calculation posted in industrial professionals. Air andor water vapor are sucked from the process into the mixing chamber at. You have to work with a manufacturer because heshe holds all the knowhow and empirical experience. Measure and calculate ejector entrainment ratio as a function of boiler. Such a vacuum system has to fulfil the following requirements. The steam jet ejector utilizes high pressure steam to compress low pressure vapours or gases. I have fabricated the eductor and it is a big success. Technology and applications gea engineering for a better world. The high velocity primary stream is produced by expanding a high.
Steam jet ejectors are an essential part in refrigeration and air conditioning. Relative suction flow of steam jet vacuum ejectors the result of calculation will be identical with the download fulltext pdf. 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. Ejector design very simply, an ejector is a pumping device.
Basic ejector components are the steam chest, nozzle, suction, throat, diffuser and they discharge fig. A steam jet ejector is a simple device that uses pressurized steam to create a partial vacuum inside an enclosed system by pumping gases and vapors out of the system. Ejector design software ejector sizing calculation. The major advantage of ejectors over vacuum pumps is the fact that they have no moving parts and are thus require little maintenance. For design of an ejector and calculating performance of the ejector, we use some basic mathematical model equations. 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. Steam jet ejector is a device for producing vacuum which is achieved by using a high pressure motive steam. Steam jet vacuum ejectors remove gases andor vapours from process operations thereby generating a vacuum in the reactor. In some applications another condenser aftercondenser can be used at the low vacuum ejector discharge. To determine vapor pressure for water, go to a set of steam tables.