Idea Transcript
INTERNATIONAL JOURNAL OF PROFESSIONAL ENGINEERING STUDIES
Volume 9 /Issue 2 / SEP 2017
DESIGN AND CFD ANALYSIS OF CONVERGENT AND DIVERGENT NOZZLE 1 1
P.VINOD KUMAR,2B.KISHORE KUMAR
PG Scholar, Department ofMECH,NALANDA INSTITUTION OF ENGINEERING AND TECHNOLOGY KantepudiSattenapalli, GUNTUR,A.P, India, Pin: 522438 2
Assistant Professor, Department of MECH,NALANDA INSTITUTION OF ENGINEERING AND TECHNOLOGY,Kantepudi,Sattenapalli, GUNTUR,A.P, India, Pin: 522438 narrowed, increasing the speed of the jet to the speed
Abstract Nozzle is a device designed to control the
of sound, and then expanded again. Above the speed
rate of flow, speed, direction, mass, shape, and/or the
of sound (but not below it) this expansion caused a
pressure of the Fluid that exhaust from them.
further increase in the speed of the jet and led to a
Convergent-divergent nozzle is the most commonly
very efficient conversion of heat energy to motion.
used nozzle since in using it the propellant can be
The theory of air resistance was first proposed by Sir
heated incombustion chamber. In this project we
Isaac Newton in 1726. According to him, an
designed a new Tri-nozzle to increase the velocity of
aerodynamic force depends on the density and
fluids flowing through it. It is designed based on
velocity of the fluid, and the shape and the size of the
basic convergent-Divergent nozzle to have same
displacing object. Newton’s theory was soon
throat area, length, convergent angle and divergent
followed by other theoretical solution of fluid motion
angle as single nozzle. But the design of Tri-nozzle is
problems. All these were restricted to flow under
optimized to have high expansion co-efficient than
idealized conditions, i.e. air was assumed to posses
single nozzle without altering the divergent angle. In
constant density and to move in response to pressure
the present paper, flow through theTri-nozzle and
and inertia. Nowadays steam turbines are the
convergent divergent nozzle study is carried out by
preferredpower source of electric power stations and
using SOLID WORKS PREMIUM 2014.The nozzle
large ships, although they usually have a different
geometry modeling and mesh generation has been
design-to make best use of the fast steam jet, de
done
Software.
Laval’s turbine had to run at an impractically high
Computational results are in goodacceptance with the
speed. But for rockets the de Laval nozzle was just
experimental results taken from the literature.
what was needed.
1.
using
SOLID
WORKS
CFD
Introduction to nozzle
Swedish engineer of French descent who, in trying to develop a more efficient steam engine, designed a turbine that was turned by jets of steam. The critical component – the one in which heat energy of the hot high-pressure steam from the boiler was converted into kinetic energy – was the nozzle from which the jet blew onto the wheel. De Laval found that the most efficient conversion occurred when the nozzle first
A nozzle is a device designed to control the direction or characteristics of a fluid flow (especially to increase velocity) as it exits (or enters) an enclosed chamber. A nozzle is often a pipe or tube of varying cross sectional area and it can be used to direct or modify the flow of a fluid (liquid or gas). Nozzles are frequently used to control the rate of flow, speed, direction, mass, shape, and/or the pressure of the stream that emerges from them. A jet exhaust produces a net thrust from the energy obtained from
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combusting fuel which is added to the inducted air.
gases is directly backwards, as any sideways
This hot air is passed through a high speed nozzle, a
component would not contribute to thrust.
propelling nozzle which enormously increases its
2. Literature review
kinetic energy. The goal of nozzle is to increase the
CONVERGENT-DIVERGENT nozzle is
kinetic energy of the flowing medium at the expense
designed for attaining speeds that are greater than
of its pressure and internal energy. Nozzles can be
speed of sound. the design of this nozzle came from
described as convergent (narrowing down from a
the area-velocity relation (dA/dV)=-(A/V)(1-M^2) M
wide diameter to a smaller diameter in the direction
is the Mach number ( which means ratio of local
of the flow) or divergent (expanding from a smaller
speed of flow to the local speed of sound) A is area
diameter to a larger one). A de Laval nozzle has a
and V is velocity The following information can be
convergent section followed by a divergent section
derived from the area-velocity relation –
and is often called a convergent-divergent nozzle
1. For incompressible flow limit, i.e. for M tends to
("con-di nozzle"). Convergent nozzles accelerate
zero, AV = constant. This is the famous volume
subsonic fluids. If the nozzle pressure ratio is high
conservation equation or continuity equation for
enough the flow will reach sonic velocity at the
incompressible flow.
narrowest point (i.e. the nozzle throat). In this
2. For M < 1, a decrease in area results in increase of
situation, the nozzle is said to be choked.
velocity and vice vera. Therefore, the velocity
Increasing the nozzle pressure ratio further
increases in a convergent duct and decreases in a
will not increase the throat Mach number beyond
Divergent duct. This result for compressible subsonic
unity. Downstream (i.e. external to the nozzle) the
flows is the same as that for incompressible flow.
flow is free to expand to supersonic velocities. Note
3. For M > 1, an increase in area results in increases
that the Mach 1 can be a very high speed for a hot
of velocity and vice versa, i.e. the velocity increases
gas; since the speed of sound varies as the square root
in a divergent duct and decreases in a convergent
of absolute temperature. Thus the speed reached at a
duct. This is directly opposite to the behavior of
nozzle throat can be far higher than the speed of
subsonic flow in divergent and convergent ducts.
sound at sea level. This fact is used extensively in
4. For M = 1, dA/A = 0, which implies that the
rocketry where hypersonic flows are required, and
location where the Mach number is unity, the area of
where propellant mixtures are deliberately chosen to
the passage is either minimum or maximum. We can
further increase the sonic speed. Divergent nozzles
easily show that the minimum in area is the only
slow fluids, if the flow is subsonic, but accelerate
physically realistic solution.
sonic or supersonic fluids. Convergent-divergent
One important point is that to attain supersonic
nozzles can therefore accelerate fluids that have
speeds we have to maintain favorable pressure ratios
choked in the convergent section to supersonic
across the nozzle. One example is attain just sonic
speeds. This CD process is more efficient than
speeds at the throat, pressure ratio to e maintained is
allowing
(Pthroat / P inlet)=0.528.
a
convergent
nozzle
to
expand
supersonically externally. The shape of the divergent section also ensures that the direction of the escaping
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Table1: speeds vs mach number
3.1 Conical Nozzles
Reg
Subs
Trans
So
Super
Hyper
High-
ime
onic
onic
nic
sonic
sonic
hyper
Ma
10.0
ch
1.2
From table.1 at transonic speeds, the flow field around the object includes both sub- and supersonic
Fig3.1 conical nozzles
parts. The transonic period begins when first zones of
1. Used in early rocket applications because of
M>1 flow appear around the object. In case of an
simplicity and ease of construction.
airfoil (such as an aircraft's wing), this typically
2. Cone gets its name from the fact that the walls
happens above the wing. Supersonic flow can
diverge at a constant angle
decelerate back to subsonic only in a normal shock;
3. A small angle produces greater thrust, because it
this typically happens before the trailing edge. (Fig.a)
maximizes the axial component of exit velocity and
As the speed increases, the zone of M>1 flow
produces a high specific impulse
increases towards both leading and trailing edges. As
4. Penalty is longer and heavier nozzle that is more
M=1 is reached and passed, the normal shock reaches
complex to build
the trailing edge and becomes a weak oblique shock:
5. At the other extreme, size and weight are
the flow decelerates over the shock, but remains
minimized by a large nozzle wall angle – Large
supersonic. A normal shock is created ahead of the
angles reduce performance at low altitude because
object, and the only subsonic zone in the flow field is
high ambient pressure causes overexpansion and flow
a small area around the object's leading edge
separation
The governing continuity, momentum, and energy
6. Primary Metric of Characterization: Divergence
equations for this quasi one-dimensional, steady,
Loss
isentropic flow can be expressed, respectively
3.2 BELL and Dual Bell
3. Types of nozzles Types of nozzles are several types. They could be based on either speed or shape. a.
Based on speed The basic types of nozzles can be differentiated as • Spray nozzles • Ramjet nozzles
b.
Based on shape The basic types of nozzles can be differentiated as • Conical • Bell
Fig3.2 (1): BELL and Dual Bell This nozzle concept was studied at the Jet Propulsion Laboratory in 1949. In the late 1960s, Rocket dyne
• Annular IJPRES
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patented this nozzle concept, which has received
2. Match exit and atmospheric pressure as closely as
attention in recent years in the U.S. and Europe. The
desired.
design of this nozzle concept with its typical inner
3. Permit afterburner operation without affecting
base nozzle, the wall in section, and the outer nozzle
main engine operation—requires variable
extension can be seen. This nozzle concept offers an
area nozzle.
altitude adaptation achieved only by nozzle wall in
4. Allow for cooling of walls if necessary.
section. In flow altitudes, controlled and symmetrical
5. Mix core and bypass streams of turbofan if
flow separation occurs at this wall in section, which
necessary.
results in a lower effective area ratio. For higher
6. Allow for thrust reversing if desired.
altitudes, the nozzle flow is attached to the wall until
7. Suppress jet noise, radar reflection, and infrared
the exit plane, and the full geometrical area ratio is
radiation (IR) if desired.
used. Because of the higher area ratio, an improved
8. Two-dimensional and axisymmetric nozzles, thrust
vacuum
vector control if desired.
performance
is
achieved.
However,
throat
additional performance losses are induced in dual-
9. Do all of the above with minimal cost, weight, and
bell nozzles.
boat tail drag while meeting life and reliability goals. 10.4Introduction to convergent and divergent nozzle A de
Laval
nozzle (or convergent-divergent
nozzle, CD nozzle or con-di nozzle) is a tube that is pinched in the middle, making a carefully balanced, asymmetric hourglass shape. It is used to accelerate a Fig 3.2(2) performance losses are induced in dual-
hot, pressurized gas passing through it to a higher
bell nozzles.
speed in the axial (thrust) direction, by converting the
3.3 Functions of Nozzle
heat energy of the flow into kinetic energy. Because
The purpose of the exhaust nozzle is to increase the
of this, the nozzle is widely used in some types
velocity of the exhaust gas before discharge from the
of steam turbines and rocket engine nozzles. It also
nozzle and to collect and straighten the gas flow. For
sees use in supersonic jet engines.
large values of thrust, the kinetic energy of the
Similar flow properties have been applied to jet
exhaust gas must be high, which implies a high
streams within astrophysics.
exhaust velocity. The pressure ratio across the nozzle controls the expansion process and the maximum uninstalled thrust for a given engine is obtained when the exit pressure (Pe) equals the ambient pressure (P0).The functions of the nozzle may be summarized by the following list: 1. Accelerate the flow to a high velocity with
Fig4: convergent and divergent nozzle 5. Conditions for operation
minimum total pressure loss.
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A de Laval nozzle will only choke at the
rate is constant. The gas flowthrough a de Laval
throat if the pressure and mass flow through the
nozzle is isentropic (gas entropy is nearly constant).
nozzle is sufficient to reach sonic speeds, otherwise
In a subsonic flow the gas is compressible,
no supersonic flow is achieved, and it will act as
and sound will propagate through it. At the "throat",
a Venturi tube; this requires the entry pressure to the
where the cross-sectional area is at its minimum, the
nozzle to be significantly above ambient at all times
gas velocity locally becomes sonic (Mach number =
(equivalently, the stagnation pressure of the jet must
1.0), a condition called choked flow. As the nozzle
be above ambient).
cross-sectional area increases, the gas begins to
In addition, the pressure of the gas at the exit
expand, and the gas flow increases to supersonic
of the expansion portion of the exhaust of a nozzle
velocities, where a sound wave will not propagate
must not be too low. Because pressure cannot travel
backwards through the gas as viewed in the frame of
upstream through the supersonic flow, the exit
reference of the nozzle (Mach number > 1.0).
pressure can be significantly below the ambient pressure into which it exhausts, but if it is too far below ambient, then the flow will cease to
5.1 Fluid flow inside convergent and divergent nozzle A
be supersonic, or the flow will separate within the expansion portion of the nozzle, forming an unstable jet that may "flop" around within the nozzle, producing a lateral thrust and possibly damaging it. In practice, ambient pressure must be no higher than roughly 2–3 times the pressure in the supersonic gas at the exit for supersonic flow to leave
converging-diverging nozzle
('condi'
nozzle, or CD-nozzle) must have a smooth area law, with a smooth throat, dA/dx=0, for the flow to remain attached to the walls. The flow starts from rest and accelerates subsonically to a maximum speed at the throat, where it may arrive at Mp* because of the pressure recovery in the diverging part.
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However, if the flow is isentropic all along the
discharge pressure. That is the normal
nozzle, be it fully subsonic or supersonic from the
situation for a nozzle working at low
throat, the isentropic equations apply
altitudes (assuming it is adapted at higher
But if the flow gets sonic at the throat,
altitudes); it also occurs at short times after
several downstream conditions may appear. The
ignition, when chamber pressure is not high
control parameter is discharge pressure, p0. Let
enough.
consider a fix-geometry CD-nozzle, discharging a
Adapted nozzle, where exit pressure equals
given gas from a reservoir with constant conditions
discharge pressure (evolution f). Notice that,
(pt,Tt). When lowering the environmental pressure,
as exit pressure pe only depends on chamber
p0, from the no flow conditions, p0=pt, we may have
conditions for a choked nozzle, a fix-
the
geometry nozzle can only work adapted at a
following
flow
regimes
(a
plot
of
pressurevariation along the nozzle is sketched in Fig. 2):
certain altitude (such that p0(z)=pe). Expansion waves appear at the exit, to expand the exhaust to the lower back pressure (evolution e); this
•
Subsonic throat, implying subsonic flow all along to the exit (evolution a in Fig 2).
is the normal situation for nozzles working under vacuum. This type of flow is named 'under-expanded'
Sonic throat (no further increase in mass-flow-rate whatever low the discharge pressure let be).
because exit pressure is not low-enough, and additional expansion takes place after exhaust.
Flow becomes supersonic after the throat, but, before
5.2 Choked flow
exit, a normal shockwave causes a sudden transition to subsonic flow (evolution c). It may happen that the flow detaches from the wall (see the corresponding
Flow becomes supersonic after the throat, with the normal shockwave just at the exit
Flow becomes supersonic after the throat, and remains supersonic until de exit, but
Oblique shock-waves appear at the exit, to compress the exhaust to the higher back pressure (evolution e). The types of flow with shock-waves (c, d and e in Fig. 2) are named
'over-expanded'
when a subsonic flow reaches M=1, whereas in liquid
because
place
when
an
almost
incompressible flow reaches the vapour pressure (of the main liquid or of a solute), and bubbles appear, with the flow suddenly jumping to M>1
there, three cases may be distinguished:
move upstream; in gas flow, choking takes place
flow,chokingtakes
section (evolution d). o
the flow, setting a limit to fluid velocity because theflow becomes supersonic and perturbations cannot
sketch). o
Chokingisa compressible flow effect that obstructs
the
supersonic flow in the diverging part of the nozzle has lowered pressure so much that a
Going on with gas flow and leaving liquid flow aside, we may notice that M=1 can only occur in a nozzle neck, either in a smooth throat where dA=0, or in a singular throat with discontinuous area slope (a kink in nozzle profile, or the end of a nozzle). Naming with a '*' variables the stage where M=1 (i.e. the sonic section, which may be a real throat within
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the nozzle or at some extrapolated imaginary throat
expansion of steam in nozzle neither heat is supplied
downstream of a subsonic nozzle.
or rejected work. As steam passes through the nozzle
5.3 Area ratio
it loses its pressure as well as heat.
Nozzle area ratio ε (or nozzle expansion ratio) is defined as nozzle exit area divided by throat *
area, ε≡Ae/A , in converging-diverging nozzles, or
The work done is equal to the adiabatic heat drop which in turn is equal to Rankine area. 6.2 Velocity of Steam:
divided by entry area in converging nozzles. Notice
Steam Enters nozzle with high pressure and
that ε sodefined is ε>1, but sometimes the inverse is
very low velocity (velocity is generally neglected).
also named 'area ratio' (this contraction area ratio is
Leaves nozzle with high velocity & low pressure
bounded between 0 and 1); however, although no
All this is due to the reason that heat energy
confusion is possible when quoting a value (if it is >1
at steam is converted into K.E as it passes through
*
*
refers to Ae/A , and if it is 1).
follows,
To see the effect of area ratio on Mach
Let
number, (14) is plotted in Fig. 1 for ideal
C-Velocity of steam at section considered (m/sec)
monoatomic (γ=5/3), diatomic (γ=7/5=1.40), and
h - enthalpy at steam at inlet
low-gamma gases as those of hot rocket exhaust
h - enthalpy at steam at outlet
(γ=1.20); gases like CO2 and H2O have intermediate
h - heat drop during expansion at steam (h
values (γ=1.3). Notice that, to get the same high
(for 1 kg of steam)
Mach number, e.g. M=3, the area ratio needed is
Gain in K.E. = adiabatic heat drop
A*/A=0.33 for γ=1.67 and A*/A=0.15 for γ=1.20, i.e. more than double exit area for the same throat area (that is why supersonic wind tunnels often use a monoatomic working gas.
−h )
=h C=√(2 * 1000*h ) = 44.72√h In practice there is loss due to friction in the nozzle and its value from 10-15% at total heat drop. Due to this the total heat drop is minimized. Let heat drop after reducing friction loss be kh Velocity (C) = 44.72 √ kh
*
Ratio A /A (i.e. throat area divided by local area) vs.
6.3 Discharge Through The Nozzle And Condition
Mach number M, for γ=1.20 (beige), γ=1.40 (green),
For Its Maximum Value:
and γ=1.67] (red).
p - initial pressure at steam
6. THEORETICAL BACK GROUND 6.1 Flows through Nozzles: The steam flow through the nozzles may be assumed as adiabatic flow. Since during the
v - initial volume at 1 kg of steam at P (m ) p -steam pressure at throat v - volume at 1kg steam at P (m ) A-area at cross section at nozzle at throat (m ) C- velocity at steam (m/s)
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Steam passing through nozzle follows adiabatic process in which
If m is the mass of steam discharged in kg/sec
p
m=
= constant
n= 1.135 for saturated steam
by substituting value of c &v we get
n= 1.3 for super saturated steam for wet steam the value at ‘n’ can be calculated by (
)
n= 1.035 + 0.1x m=
x- dryness fraction at steam (initial)
p p v [1- ( p )
√( 2{
m=
Dr.Zenner’s equation
]})
p p p v [( p ) - ( p )
√ (2{
]})
workdone per 1 kg at steam during the cycle it is obvious form above equation that there is only p one value at the ratio (critical pressure ratio) p
(Rankine cycle) (p v - p v )
W=
which will produce max discharge Already we know Gain in K.E = adiabatic heat drop = workdone during Ranlinecycl Per 1 kg =
constant
(p v - p v )
p v (1-
=
p p [( p ) - ( p )
=>
p => [ ( p )
) ………….(1)
p =>( p )
Also p
and this can be obtained by differenciating m with p respect to p and equating to zero p and other quantities except p remains here
v = ( v ) => =>v = v (
p
p = ( p )
p )
………(2) ……..(3)
p )( p ) ]
- (
p ) ( p )
= (
p =>( p )
= p
] =0
= ( + 1 2)
p
+1 ) p = ( 2
p
2 p = (
+ 1)
equation 2 in 1 Hence discharge through the nozzle will be =
p v (1-
=
p v [1-
maximum when critical pressure ratio is
) p ( p ) ]
=
p v [1-
=
p p v [1- ( p )
=2{
(
p
=
By substituting
]
+ 1)
p
p value in mass equation we get
the maximum discharge
p p v [1- ( p ) [1- (
2 p = (
p ) ]
]} m=
C = √ (2{
p
)
√ (2{
p p p v [( p ) - ( p )
]})
]}
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√ (2{
= [(2
+ 1)
]
p v
[[ (2
Volume 9 /Issue 2 / SEP 2017
+ 1)
]
–
p
p =( ) =( )
p Specific volume v = v ( p )
]})
Apparent temperature
[(2
+ 1)
–
due to following reasons I.
p v [[ (2
+ 1)
–
II. III.
− 1]]}) p v [ (2
√ (2{
+ 1)
Internal friction of steam itself and The shock losses
Most of these frictional losses occur between the –
− 1)] })
throat and exit in convergent divergent nozzle. These frictional losses entail the following effects.
p v [ (2
√ (2{
+ 1)
1.
–
2. A √ n ( ) [(2
By substituting
p
The expansion is no more isentropic and enthalpy drop is reduced.
)]}) =
The friction between the nozzle surface and steam
= (
+ 1)
− 1]})
= [(
p v [[ (2
√ (2{
+ 1)
Nozzle efficiency:
velocity of steam for a given pressure drop is reduced
= [(2
–
p ( p )
When the steam flows through a nozzle the final √ (2{
+ 1)
+ 1)
]})
= [(2
p v [[ (2
√ (2{
=
=
The final dryness fraction at steam is increased as
+ 1)
the
kinetic
energy gets
converted into heat due to friction and is observed by steam.
2 p = (
+ 1)
in equation c
3.
we get
The specific volume of steam is increased as the steam becomes more dry due to this
= √ 2(
) p v [1- ((2
= √ 2(
) p v [1-
= √ 2(
)p v (
= √ 2(
)p v
+ 1)
frictional reheating
)
] )
From maximum equation, it is evident that the
1
K= =
=
3 2
1-2-2 - actual 1-2-3 -3 isentropic
maximum mass flow depends only on the inlet conditions ( p v ) and the throat area.and it is independent at final pressure at steam i.e., exit at the nozzle Note: p
= constant
= constant = constant
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Nozzle efficiency is the ratio of actual enthalpy drp to
It is an easy-to-learn tool which makes it
the isentropyenthalpy drop between the same
possible for mechanical designers to quickly sketch
pressure.
ideas, experiment with features and dimensions, and
Nozzle efficiency =
produce models and detailed drawings. A Solid Works model consists of parts, assemblies,
If actual velocity at exit from the nozzle is
and the
velocity at exit when the flow is isentropic is
then
and drawings.
using steady flow energy equation. In each case we
Typically, we begin with a sketch, create a base feature, and then add more features to
have
the model. (One can also begin with an
ℎ +
= ℎ +
ℎ +
= ℎ
=>ℎ - ℎ =
+
=>ℎ - ℎ
imported surface or solid geometry).
=
We are free to refine our design by adding, changing, or reordering features.
Nozzle efficiency = Inlet velocity
Associatively between parts, assemblies, and drawings assures that changes made to
is negligibly small
one view are automatically made to all
Nozzle efficiency =
other views. Sometimes velocity coefficient is defined as the ratio
of actual exit velocity to the exit velocity when the flow is isentropic between the same pressures.
any time in the design process.
i.e., velocity coefficient =
We can generate drawings or assemblies at
The Solid works software lets us customize functionality to suit our needs.
Velocity coefficient is the square root of the nozzle
8. Modeling of convergent divergent nozzle
efficiency when the inlet velocity is assumed to be
First select a new file and front plane
negligible.
Draw sketch as follows
Enthalpy drop = (( = (
p
])
p )
= √ {2( v =v ( =
p ) p v [1- ( p )
(
p
p
p ) p v [1- ( p )
]}
p ) p )
Then go to features and make revolve
= m = 7. SOLID WORKS Solid
Works
is
mechanical
design
automation software that takes advantage of the familiar Microsoft Windows graphical user interface.
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Table2: List of different general settings in SolidWorks Flow Simulation Now flow simulation Wizard
3d model of c & d nozzle 9. FLOW SIMULATION SolidWorks Flow Simulation 2010 is a fluid flow analysis
add-in
package
that
is
available
forSolidWorks in order to obtain solutions to the full Navier-Stokes equations that govem the motion of fluids. Other packages that can be added to SolidWorks
include
SolidWorks
Motion
Set units
and
SolidWorks Simulation. A fluid flow analysis using Flow Simulation involves a number of basic steps that are shown in the following flowchart in figure.
Flow type- internal in x-axis direction
Figure: Flowchart for fluid flow analysis using Solidworks Flow Simulation
General setting Next gases add air as fluid
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Computational domain
Mach number
9.1 For 5 bar inlet pressure
Goals result table
Boundary conditions Inlet mass flow rate 50 kg/sec, pressure 5 bar (select inside faces)
9.2 For pressure 10bars Boundary conditions Give mass flow rate 50kg/s and pressure 10bars Result
Pressure
Pressure
Velocity
Velocity
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Mach number
Goals tables
Volume 9 /Issue 2 / SEP 2017
Mach number
10.2 10 bar Pressure
Velocity
10. Graphs 10.1 5bar Pressure
Mach number
Velocity
Table: Results Given Pressure 5bars 10bars
Pressure
Velocity
22.14 22.42
661.617 740.168
Mach number 4.57 3.28
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11. Conclusion:
field thermal structural simulations in Micro
Modeling and analysis of Convergent and
Valves and Micro channels” CFD Research
divergent nozzle is done in Solidworks 2016
Corporation.
Modeling of single nozzle is done by using various commands in solid works and
Velocity of nozzle at 5 bar and 10 bar
“Navier-Stokes
structure
of
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