Unit iii unit iii steam nozzles and turbines flow of steam through nozzles, shapes of nozzles, effect of friction, critical pressure ratio,supersaturated flow. Ratio of actual exit velocity to the exit velocity when the flow is isentropic between the same pressure. Twodimensional kinetics tdk computer program, which has been combined with a boundary layer module blm, is the industry standard jannaf joint. Both the conventional conventional bell and unconventional aerospike and expansiondeflection nozzles can be the subject of consideration of the moc. It does not cover the use of nozzles and venturi nozzles in pipe sizes less than 50 mm or more than 630 mm, or for pipe reynolds numbers below 0.
In this nozzle the cross sectional area gradually decreases from the entrance area to the minimum area which is the exit. Steam nozzles free download as powerpoint presentation. Herewith we have shared the steam boilers, engines, nozzle, turbines mechanical mcqs pdf mechanical engineering multiple choice questions and answers pdf. It is not applicable to the measurement of pulsating flow. Introduction, intake efficiency, nozzle efficiency duration. Automated nozzle design through axissymmetric method of. The adiabatic flow process of gas or steam in a nozzle is not only widely used in steam turbines or other power equipment, but also applied to ejectors, impellertype compressors, burners and other thermal devices in air conditioning, ventilation and gas engineering.
The second step is that ligaments collapse and break up further into very small pieces as fine water droplets. Hunter offers an assortment of nozzle options for any lawn sprinkler system adjustable, fixed, specialty nozzles, and. Many of the owner specifications for refinery equipment do not allow setons, so this is another consideration. Steam nozzles ppt steam nozzles a nozzle is a duct of. Nozzle loads are defined as the net forces and moments exerted on equipment nozzles from the weight and thermal expansion of connected piping and other equipment. Fluid mechanics phenomena in rocket nozzles some features.
Nozzles are frequently used to control the rate of flow, speed, direction, mass, shape, andor the pressure of the stream that emerges from them. The flow nozzle is a type of differential pressure drop device in a differential pressure drop device the flow is calculated by measuring the pressure drop over an obstructions inserted in the flow. Hydraulic turbines pelton wheel, francis turbine and kaplan turbine. The kinetic energies at the inlets and outlet of ejector are neglected, because. Steam nozzles nozzle statistical mechanics free 30day. The picture to the left shows spiral nozzles being used to extinguish a fire. Mechanical power engineering department faculty of engineering. Pressure downstream of nozzle industrial professionals. Spiral nozzles can also be used for dust suppression applications, as shown on the right. Aerospace engineering jet aircraft propulsion nptel. The following is a general guideline to help select the proper nozzles for the job. Nozzle is defined as a device intended to control the speed and direction, or alteration of a liquid stream particularly to expand speed as it exits or enters an encased chamber or pipe. The main use of steam nozzle in steam turbines is to produce a jet of steam with a high velocity.
Lecture series on steam and gas power systems by prof. Supersonic flow separation with application to rocket engine nozzles department of mechanics, royal institute of technology se100 44 stockholm, sweden abstract the increasing demand for higher performance in rocket launchers promotes the development of nozzles with higher performance, which basically is achieved by increasing the expansion ratio. Steam enters nozzle at 10bar, 500c and leaves at 6 bar. The subject of sprinkle large droplet formation from the nozzles is also examined in detail and is shown to be nonsignificant. This development allows the process for designing rocket nozzles to be automated, fa. The smallest section of the nozzle is called throat. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Storing liquids in tanks is essential for many process industry applications, for example chemicals for finishing and surface treatment applications, as is the need to agitate the contents to avoid separation and sedimentation.
You will have many different nozzles on vessels and tanks. Unit 4 flow through nozzles velocity and heat drop, mass discharge through a nozzle, critical pressure ratio and its significance, effect of friction, nozzle efficiency, supersaturated flow, design pressure ratio. The air friction tears the ligaments from the main flow of water. In the step of admission of steam turbines reation there are several nozzles that distribute the steam to the blades. Nozzles have a threaded base which screws directly into the manifold. If you want to simplify ship management, analyze data, improve data security, facilitate information access and raise business efficiency, then nozzle ship. You will have inlet and outlet nozzles on exchangers. Sprinkler nozzles, also referred to as spray nozzles, are an important, but often overlooked component of welldesigned irrigation systems. All nozzles are available in three spigot sizes, to fit 916, 22 or 16 14 mm, 17 mm and 19 mm diameter holes in the riser. Lec10 steam power cycle, steam nozzle lecture series on applied thermodynamics for marine systems by prof.
The process in nozzles, mixing and diffuser is assumed to be ideal and then isentropic. The effect, on evaporation rate, of ambient climatic. Steam boilers, engines, nozzle, turbines mechanical mcqs pdf. Flow of gases and steam through nozzles example, the required pressure in the combustion chamber of the space shuttle ssme engine was 20. In other words, this discussion about pressure wave patterns suggests the following.
Mach number and speed of sound the mach number is defined as the ratio of the value of the local flow velocity, v, to the local speed of sound, c. In the last lecture we saw how the throat area of the nozzle controls the mass flow rate. Fluids can be recirculated through tanks to achieve separation which helps to optimise chemical action in dip tanks, although the process can. Nozzles are positioned onto the manifold mold back and retainer plates secure the entire system in place. Steam flow in nozzle and the nozzle calculation scientific. Eductor nozzles for chemical finishing and surface treaments. A quantitative approach to selecting nozzle flow rate and. The contour formed allows for a smooth throat, shock free nozzle. The thrust optimised parabolic nozzle introduction in the early 1950s, rocketeers attempted to devise the perfect nozzle. Even the smallest flow rate nozzle, regardless of stream type, if operated long enough, can suppress any fire in a confined compartment.
Steam nozzles and turbines mechanical engineering questions. The variation of steam pressure in the nozzle depends upon the velocity, specific volume and dryness fraction of steam. The convergent nozzle is a spout that begins large and gets smaller, an abatement in crosssectional region. This ensures a secure, leak proof connection to the manifold and facilitates construction of our unitized systems. Converging nozzle in a subsonic flow will have decreasing area along the flow direction. When the sugar cane is offloaded from the truck it produces a lot of dust that can be hazardous to the workers, so spiral nozzles are used to suppress the dust.
Convergentdivergent type of nozzles are mostly used for supersonic flows because it is impossible to create supersonic flows mach number more than one in convergent type of nozzle and therefore it restricts us to a limited amount of mass flow through a. For the love of physics walter lewin may 16, 2011 duration. For pumps, nozzle loads are specified in api 610 or other pump codes and standards such as ansi, etc. If the flow nozzle in the system in the attached drawing has an inlet pressure, p2, of 165 psig, what will be the pressure after exiting the nozzle at p3 after pressure recovery, downstream of the vc if the vessel downstream is at atmospheric pressure p4. Explanation of nozzles a white paper from assmann polyethylene tanks come with a variety of nozzles. The method allows for the nozzle boundary to be formed through a full method of characteristics solution. Applied thermodynamics videos, lectures, classes, courses, books, tutorials nptel thermodynamics videos, thermodynamics video lectures, thermodynamics video classes. It is very useful for all kind of gate, ssc, ese and other competitive examinations. Assuming an adiabatic expansion in the nozzle, the mass flow is calculated as follows. Nozzles visual encyclopedia of chemical engineering.
As mcje says, the reinforcement calculations are slightly. Critical flow nozzles are also called sonic chokes. How to calculate the steam flow through each nozzle. The project on development of remaining three quadrants to nptel phasei under grant in aid nmeict, mhrd, new delhi. The steamhas a very high velocity at the end of the expansion, and the enthalpy decreases as expansion takes place. Unit 4 flow through nozzles velocity and heat drop, mass discharge through a nozzle, critical pressure ratio and its significance, effect of friction, nozzle efficiency, supersaturated flow. It covers the important area of the fog plume pattern of impaction pin nozzles and examines fogplume uniformity. Cobusvanj, it is pretty much a matter of shop preference. Only these nozzles will be considered in the following. Due to friction between the fluid and the walls of the nozzle within the fluid itself the expansion process is irreversible although still approximately adiabatic. The proper nozzle ensures accurate, even delivery of water in the pattern you need.
Sirik physicaltechnical group dobrolubova street, 2, 29, pavlograd, dnepropetrovsk region, 51400 ukraine the results of computing experiments are presented for the steam and gas stream motion in convergingdiverging flow element called laval nozzle and applied in. We denote outlet of the driving and the suction nozzle and mixing section as 4, 9 and 5, respectively. Seton versus setin nozzles boiler and pressure vessel. All nozzles are available with a singlespring or an optional doublespring configuration for pressures over 60 psi 4. Steam nozzles and turbines mechanical engineering questions set 27 mcq steam boilers edit practice test. For the process plant engineering and design this more commonly relates to an equipment connection you will have suction and discharge nozzles on pumps. Now we will explore the effects of the shape of the nozzle downstream of the throat.
The ratio between critical pressure and initial pressure for a. Vanita thakkar bit 51 factors affecting nozzle effeciency nozzle type velocity coefficient roughly cast nozzles 0. Vtunptelnmeict project progress report the project on. Mix play all mix steam and gas power systems youtube lec 47. Numerical study on condensation process of steam flow in. Mar 07, 2015 vanita thakkar bit 51 factors affecting nozzle effeciency nozzle type velocity coefficient roughly cast nozzles 0. A sonic choke may provide a simple way to regulate a gas flow.
The flow of steam through nozzles may be regarded as adiabatic expansion. If you want to simplify ship management, analyze data, improve data security, facilitate information access and raise business efficiency, then nozzle ship management system software is the right solution for you. This is known as critical pressure ratio and different for different fluids. Setin nozzles pretty much can always be double welded, where this is not usually possible for setons. Impulse and reaction principles, compounding, velocity diagrams for simple and multistage turbines, speed regulationsgovernors and nozzle governors. Pipe flow measurement flow nozzles iso 51673, bs 10421. Supersonic nozzle flow in the twophase ejector as water. How to determine the steam flow in the nozzles of the stage. By establishing a shock wave the sonic choke establish a fixed flow rate unaffected by the differential pressure, any fluctuations or changes in downstream pressure. Pressure downstream of nozzle posted in industrial professionals. Steam ejector is an important component in engineering applications, which require high. Bellshape nozzles or parabolic nozzles, which are as efficiency as the simplest conical nozzle, but shorter and lighter, though more expensive to manufacture. However, ligament can only be lasted for a very short period, say, 1.
Most of the analysis we considered so far neglected density variations. They used the semialgebraic method of characteristics of supersonic flow to devise such a nozzle, for whatever nozzle expansion ratio. Impulse and reaction stage, degree of reaction, velocity triangle, week 6. Isentropic flow through convergingdiverging nozzles nptel. Often the nozzles are misapplied and can cause problems shortly after installation. Oxidizer and fuel pumps are powered by combustion turbines that use fuel and engine oxidant as fuel or have other fuel 16, s. The area of crosssection should therefore, be constant at all points. Unispray systems providing nozzles, pipe systems, quick. Nozzles are actually used to modify the flow of a fluid i. A quantitative approach to selecting nozzle flow rate and stream, part 2 by jason n.
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