Convergent divergent nozzle shock wave cfd results youtube. There is a school of thought that contends that the convergent nozzle is an inefficient version of the convergent divergent nozzle. A nozzle of a variable length from the inlet to exit has been used for the purpose of the. To get a basic feel for the behavior of the nozzle imagine performing the simple experiment shown in figure 2. The cd nozzle exhausts this air into cylinder b, which takes the place of the tank. Ramjets and rockets typically use a fixed convergent section followed by a fixed divergent section for the design of the nozzle. A propelling nozzle is a nozzle that converts the internal energy of a working gas into propulsive force. Part 2 of the work is on prediction of optimal axial gap convergent divergent nozzle study is carried out by. It will be assumed that the flow can be adequately modeled by assuming it to be. Divergent nozzle article about divergent nozzle by the. With the convergent divergent shrouds the main variable studied was the ratio shroud throat areashroud exit area. Aiaa 20010078 experimental investigation of transonic.
Combine multiple pdf files into one pdf, try foxit pdf merge tool online free and easy to use. In the divergent parts, the friction loss may be taken as 0. The convergingdiverging verification cdv nozzle is a verfication case involving the flow of inviscid, nonheatconducting air through a convergingdiverging nozzle. This nozzle configuration is called a convergent divergent, or cd, nozzle. As a liquid enters the smaller crossarea, it needs to accelerate because of the production of mass. To maintain a constant amount of fluid moving through the restricted portion of the nozzle, the fluid must move faster. 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. Isentropic nozzles apply equations for isentropic flow with area change to nozzles nozzles increases velocity of fluid no work converts thermal energy to ke tu for conventional wallbounded nozzles, two types. This lab experiment was based on determining the various kinds of shock waves produced in a convergentdivergent nozzle by altering the effect of the pressure ratio respectively.
The throat of the nozzle is dimensioned such that its inside diameter is equal to the. Tech cadcam smbs, vit university, india abstract the effects of mach number and nozzle pressure ratios npr on mass flow rate, maximum pressure. Cfd analysis of convergent divergent supersonic nozzle. The influence of design pressure ratio and divergence angle. Aiaa 20010078 experimental investigation of transonic resonance with convergentdivergent nozzles k. The present paper is concerned with the study of compressible flow in a convergingdiverging nozzle. Volume 4 flow analysis in a convergentdivergent nozzle using cfd.
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. Combines pdf files, views them in a browser and downloads. Merge pdf online combine pdf files for free foxit software. Lakshman flow analysis in a convergentdivergent nozzle using cfd international journal of research in mechanical engineering volume 1, issue 2, octoberdecember. The objective of this paper is to computationally analyse shock waves in the convergent divergent cd nozzle. Pdf computational modeling of a typical supersonic. As static pressure inside the nozzle is lower than the ambient pressure there is a moment relative to the hinge at the throat plane which tends to close the divergent part of the. Steam expands in a set of nozzle from 10 bar, 300 0c to 1 bar. A convergent divergent gas nozzle atomizes a liquid provided through a lid delivery tube having an aperture which is centered within a central gas conduit of an upstream mixing block connected to the nozzle. This also can represent convergent nozzle for a fluid whose peculiarity is that while both velocity and specific volume increase, the rate of specific volume increase is less than that of the velocity, thus resulting in increasing value of v 200 elements of heat engines vol.
Depending on the exit mach number a suitable nozzle is designed. A convergent nozzle is a nozzle that starts big and gets smallera decrease in crosssectional area. Isentropic nozzles georgia institute of technology. Values of the index n and the critical pressure ratio r, for different fluids are given in the table below. Pdf cfd analysis of convergentdivergent and contour nozzle.
In this paper, a nozzle is a device designed to control the direction or characteristics of a fluid flow especially to increase velocity as it exits or enter an enclosed chamber or pipe via orifice. The aperture of the liquid delivery tube is located just upstream of a narrowed throat of the nozzle. The experiment was conducted using computational fluid dynamics and the results produced were compared with the theoretical results to present the accuracy of the. Use the anemometer to measure the maximum possible air velocity at the exit of the discharge tube when the inlet valve is fully opened. The jet velocity will rise to a maxima at the throat of the nozzle smallest area and then exit the nozzle and expand again against atmospheric pressure. For subsonic flows, convergent nozzle is used and for supersonic flows a convergentdivergent cd nozzle is employed.
A small convergent divergent nozzle throat diameter 6. Madhu b p, syed sameer, kalyana kumar m and mahendra mani g, cfd analysis of convergentdivergent and contour nozzle, international journal of mechanical engineering and technology, 88, 2017, pp. Flow in a convergentdivergent nozzle is studied for pressure ratios npr of 111 and exittothroat area ratios of 1. Convergent divergent nozzle flow velocity and area equation. A method to alleviate the mentioned effect is to leave the divergent part of the nozzle floating. Cfd results for shock wave inside the divergent part of the convergent divergent nozzle. Convergent divergent nozzle flow velocity and area equation and calculator throat velocity equation. Media in category convergent divergent nozzles the following 27 files are in this category, out of 27 total. Numerical investigation of transonic resonance with a convergentdivergent nozzle chingy. An arrangement in which the forward portion of the. In a convergent nozzle, there is an increase in velocity and. Alexandria university faculty of engineering mechanical engineering department under the supervision of dr. Influence of geometry on the efficiency of convergent. Additive manufacturing processes such as selective laser melting and electron beam melting require small particle sizes.
A convergingdiverging nozzle condi nozzle, or cdnozzle, is the only one to get supersonic flows with m 1 when chocked. Alexandria university faculty of engineering mechanical engineering department under the. Modeling and simulation of convergentdivergent nozzle. A convergingdiverging nozzle with reservoir pressure fixed. Determination of efficiency of converging diverging. Flow characteristic through convergentdivergent nozzle. It gives the profile for the divergent part of the cd nozzle. It transforms the thermal energy of highpressure liquid flow at the inlet to the kinetic energy of highspeed twophase flow at the outlet. How to merge pdfs and combine pdf files adobe acrobat dc. A nozzle is a relatively simple device, just a specially shaped tube through which hot gases flow. To keep up a consistent measure of liquid traveling through the confined bit of the spout, the liquid must move faster. The divergent section of the nozzle is downstream of this line. Our pdf merger allows you to quickly combine multiple pdf files into one single pdf document, in just a few clicks. Oct 10, 2015 this is a very simple program for designing convergent divergent cd nozzle.
To quantify variation in the minimum length of the. Arulmurugu 2 1,2department of mechanical engineering, anna university regional centre, coimbatore tamil nadu, india abstract the performance of a two phase flow nozzle, as an expander to generate is power. This free online tool allows to combine multiple pdf or image files into a single pdf document. Here we use a converging diverging nozzle to connect two air cylinders. Measurements have been made of nozzle base pressure, and thrust effxiencles derived with reference to.
A convergingdiverging nozzle condi nozzle, or cd nozzle, is the only one to get supersonic flows with m 1 when chocked. The nozzle is an essential component of the ejector. Part 2 of the work is on prediction of optimal axial gap convergent divergent nozzle study is carried out by using a finite volume commercial code, fluent 6. The performance of conical convergentdivergent nozzles of area. Determination of efficiency of converging diverging nozzles. The convergent parts of the nozzle are sharp and frictionless. 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. It is used to accelerate a hot, pressurized gas passing through it to a higher supersonic speed in the axial thrust direction, by converting the heat energy of the.
Nozzle geometry, expansion ratios, flow and boundary conditions have been drawn on the basis of the literature survey. Convergent divergent 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. Divergent nozzle using computational fluid dynamics published at. If the steam floe rate is 1 kgs and the initial velocity of steam is negligible, find the minimum area of the nozzle. Nozzles are actually used to modify the flow of a fluid i. This tube is fitted with a pointer which moves along a profile of the nozzle under test so as to. Problem 12 air flow isentropica lly through a convergent divergent nozzle with inlet area of 5.
Choose from a variety of file types multiple pdf files, microsoft word documents, microsoft excel spreadsheets, microsoft powerpoint. Apr 11, 2015 cfd results for shock wave inside the divergent part of the convergent divergent nozzle. Supersonic flow in cd nozzles presents a rich behaviour, with shock waves and expansion. The thrust of the best model was some 9% less than that of the convergent divergent reference nozzle. Simulation of expansion is carried on ansys fluent 14software using. Pdf computational analysis of shockwave in convergent. This paper aims to study the behavior of flow in convergent divergent nozzle by analyzing various parameters like pressure, temperature and velocity using computational fluid dynamics softwarec. An efficient nozzle provides high kinetic energy at the nozzle outlet for high pressure recovery in the ejector. The characteristics of a supersonic jet are characterized by the stagnation pressure ratio popa, exit mach number me and the nozzle configuration. The unsteady compressible navierstokes equations along with.
The flow will accelerate further only if the shape of the nozzle behind the throat is divergent. The influence of design pressure ratio and divergence. From a theoretical and experimental investigation of the flow in an illustrative channel with convergentdivergent area variation, the behavior of the flow along the channel was found to be generally similar in trend to the flow in a stationary convergentdivergent nozzle. Easily combine multiple files into one pdf document. Bencic nasa glenn research center cleveland, oh 445 this is a preprint or reprint of a paper intended for presentation at a conference. Convergentdivergent nozzle article about convergent. Cylinder a contains air at high pressure, and takes the place of the chamber.
Feb 15, 2014 how does a rocket engine and nozzle work. In a convergent nozzle, there is an increase in velocity. The present work focuses on the cfd simulation of a convergent divergent nozzle undergoing compressible. As a fluid enters the smaller crosssection, it has to speed up due to the conservation of mass. This is a classic onedimensional, steady, compressible flow problem discussed in most compressible flow textbooks, such as reference 1 by anderson. The thrust of the best model was some 9% less than that of the convergentdivergent reference nozzle. Marry engineering college, india 2associate professor, vitam engineering college, india 3m. The convergent divergent nozzle finds application in many areas of industry and technology. Determine 4 suitable flow velocities at which to take readings. Simulation of back pressure effect on behaviour of convergent divergent nozzle diyala journal of engineering sciences, vol. A convergingdiverging nozzle condi nozzle, or cdnozzle, is the only one to get supersonic flows with m1 when chocked. Supersonic flow in cdnozzles presents a rich behaviour, with shock waves and expansion. Optimization of actuation and cooling systems for advanced. A novel convergentdivergent annular nozzle design for close.
The convergent nozzle is a spout that begins large and gets smaller, an abatement in crosssectional region. Why a divergent nozzle is used in supersonic engines. The coding was done in matlab to obtain the contour of the divergent section for seven different exit mach numbers viz. May 05, 2015 a nozzle is a relatively simple device, just a specially shaped tube through which hot gases flow. Zaman national aeronautics and space administration glennresearchcenter cleveland,ohio445 abstract at pressure ratios lower than the design value, convergentdivergent cd nozzles often undergo a. This lab experiment was based on determining the various kinds of shock waves produced in a convergent divergent nozzle by altering the effect of the pressure ratio respectively.
The area ratio is accurate for mach number m up to 5. This is a very simple program for designing convergentdivergent cd nozzle. Choking criteria of a convergent nozzle flow are proposed from experiment and theory. Divergent nozzle article about divergent nozzle by the free. Convergent divergent nozzle cfd online discussion forums. Jul 16, 2008 the convergingdiverging verification cdv nozzle is a verfication case involving the flow of inviscid, nonheatconducting air through a convergingdiverging nozzle. The present study deals with the impingement characteristics of a supersonic jet issuing out of a convergent divergent nozzle over an axisymmetric jet deflector. Nozzle is used to convert pressure energy to kinetic energy in order to produce thrust. Numerical investigation of transonic resonance with a. Creation of twodimensional geometry of the nozzle and meshing is done on workbench of ansys 14.