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The intent of our undertaking is to plan an fumes system for a 800cc engine vehicle that is being made by the pupils of our college for FSAE event. This auto has a rear mounted engine, hence we our fumes system has to be designed consequently. Besides we have to maintain in head that the system provides maximal interpolation loss and minimal power loss.

An fumes system consists of an fumes manifold, a forepart pipe, a accelerator convertor, a chief silencer or silencer, and a tail pipe with an exhaust tip.The public presentation silencer must hold an recess and an mercantile establishment pipe that is the same size as your forepart pipe and your tail pipe. Your front pipe and your tail pipe should besides hold the same diameter. We have to considerA back force per unit area, engine ‘s power and engine’sA maximal RPM.

A rational design procedure depends on the acceptance of a design methodological analysis based on prognostic mold of acoustic behaviour. We used some empirical expression ‘s to find the length of the primary pipe of our fumes system and the speed of the fumes gases, and so we verified these consequences utilizing the bernaullies equation sing the frictional losingss and the crook losingss. We used the same equation for the designing of silencers besides. Once we got the values such as length of primary pipe, length of silencer, diameter of pipe and the silencer, speed of exhaust gases in the primary pipe and the silencer and besides the force per unit area at assorted points in the fumes system. We so analyze the fumes gas flows utilizing these parametric quantities in GAMBIT and FLUENT.

We have gone in inside informations about two types of silencer, one is the brooding type and the other is absorbent type. The brooding type of silencer can be normally found in the autos used for domestic intent whereas the absorbent type of silencer is used in the public presentation vehicles. This is because of the fact that in brooding type of silencer, baffles are used or in laymen linguistic communication the fumes gases have to go through through many obstructors before it comes out of the fumes system hence the engine have to make some work to force the fumes gases out of the system, but the interpolations loss in this silencer is really high although we have to compromise with some power loss. Whereas in instance of absorbent silencer, there are no obstructors in the manner of the fumes gases hence there is no power loss in this type of silencer although we have to compromise a small with the sound produced. Since we are planing a silencer for a public presentation auto where we have to do certain that maximal power of the engine is being utilised, hence we have opted to travel for absorbent type of a silencer for our auto.

Engine Specification

Chapter 1

Introduction

Major beginning of noise pollution is Engine. These engines are used for assorted intents such as, in power workss, cars, engines, and in assorted fabricating machineries. Noise pollution created by engines becomes a critical concern when used in residential countries or countries where noise creates hazard.

The chief beginnings of noise in an engine are the exhaust noise and the noise produced due to clash of assorted parts of the engine. The exhaust noise is the most dominant. To cut down this noise, assorted sort of silencers are normally used. The degree of exhaust noise decrease depends upon the building and the on the job process of silencers.

The primary intent of the silencer is to cut down or smother the noise emitted by the internal burning engine. The fumes is passed through a series of Chamberss in reactive type silencers or straight through a pierced pipe wrapped with sound dampening stuff in an absorbent type silencer. Both types have strengths and failings. The reactive type silencer is normally restrictive and prevents even the good engine sounds from coming through, but does a good occupation of cut downing noise. On the other manus, most absorbent type silencers are less restrictive, but let excessively much engine noise to come through. Regardless of the packing stuff, absorbent type silencers tend to acquire noisier with age.

1.1 EXHAUST SYSTEM

Automobile fumes system consist of assorted devices, which are used for dispatching burned gases. Exhaust systems consists of tube, which are for breathing out exhaust gases. All the burnt gases are exhaled from an engine utilizing one or moreA exhaustA pipes. These gases are expelled out through several devices like, catalytic convertor, A mufflerA /silencer, cylinderA caput, exhaust manifold, turbocharger

Since our undertaking is based on UAV application, hence emanation control is non the chief concern hence catalytic convertor is non being used in our fumes system.

1.1.1 Exhaust Pipe

Exhaust Pipes are used to convey assorted toxic gases. Temperature of exhaust gases is really hot, so the stuff must be lasting and heat resistant. The exhaust pipes joins exhaust manifold, A mufflerA and catalytic convertors together.

1.1.2 Exhaust Manifold Gaskets

Exhaust Manifold Gaskets consists of strong web of pipes that are used for roll uping the gases from cylinders, passes them straight to the fumes. Manifold gaskets are largely made of dramatis personae Fe, embossed steel, high temperature fiber stuff, black lead and other ceramic complexs. The chief map of gasket is to seal the connexion between the manifold and cylinder caput. Escape of gas is prevented by gas manifold.

1.1.3 Exhaust Flange

Exhaust Flange is a type of projecting rim used for attaching, fall ining or fixing tightly assorted exhaust pipes with the aid of nuts and bolts. Largely unstained steel Al, Alloy steel, C steel, hardened steel are used for fabrication of these rims.

CH 2 TYPES OF Muffler/Silencer

The most common component used to hush generator fumess are reactive silencers. Reactive silencers are available in a broad scope of cost and public presentation. The noise is reduced by coercing the fumes air to go through through a series of tubings and Chamberss. Each component in the silencer has sound decrease belongingss that vary greatly with acoustic frequence, and it is the commixture and matching of these elements that constitutes muffler design.

2.5.1 Reactive silencer

2, 3 or 4-chamber designs

All metal building with no sound absorbent stuffs

Maximize ratio of organic structure diameter to shriek diameter & A ; volume

Over the old ages a series of silencer classs have evolved to depict the approximative interpolation loss public presentation for engine fumes silencers. The words do non needfully connote where the silencers should be used. Note that better quality ( e.g. higher interpolation loss ) silencers will be physically larger than lower quality units. Although size is non the lone factor, you can non acquire good acoustical public presentation without it.

Exhaust Muffler Grades

Industrial/Commercial: IL = 15 to 25 assumed name

Body/Pipe = 2 to 2.5 Length/Pipe = 5 to 6.5

Residential Class: IL = 20 to 30 assumed name

Body/Pipe = 2 to 2.5 Length/Pipe = 6 to 10

Critical Class: IL = 25 to 35 assumed name

Body/Pipe = 3 Length/Pipe = 8 to 10

Super Critical Grade: IL = 35 to 45 assumed name

Body/Pipe = 3 Length/Pipe = 10 to 16

2.5.2 Absorptive ( secondary ) silencers

Absorbent silencers use fibreglass or other acoustic fill stuff to absorb noise without any reactive elements ( tubes & amp ; Chamberss ) . Absorbent silencers provide really small noise decrease at low frequences, so they should ne’er be used as the lone silencer in an engine fumes system. The straight-through design shown here is really utile for absorbing high frequence spontaneous noise created by reactive silencers.

Reactive/Absorptive Silencers

Some makers offer combination reactive/absorptive silencers in a individual bundle unit. Although this sounds like a good thought, you by and large will acquire better overall acoustical public presentation by utilizing a reactive silencer followed by a separate absorbent silencer. Of class, a combination silencer may be appropriate for installings where there is non adequate length in the fumes system to suit two separate units.

These devices contain fibreglass shielded from the exhaust watercourse by pierced sheet metal

Provides broad-band noise control

Reactive silencers work best at 125 Hz and 250 Hz ( IL is reduced at high frequences by self-noise )

Absorbent silencers work best at 1000Hz and 2000 Hz

Ch. 3 Exhaust system Design

Choice parametric quantities – The usage of an exhaust silencer is prompted by the demand to cut down the engine fumes noise. Acoustical, aerodynamic, mechanical, Structure public presentation, Shape are the basic choice factors for the silencer

Acoustic public presentation – The acoustical public presentation standard specifies the minimal interpolation loss ( IL ) of the silencer, and is normally presented in IL values for each octave set every bit good as an overall expected noise decrease value. The interpolation loss is determined from the free-field sound force per unit area degrees measured at the same comparative locations with regard to the mercantile establishment of the unsilenced and silenced systems. The IL of a silencer is basically determined by mensurating the noise degrees of a shrieking systems before and after the interpolation of a silencer in the exhaust watercourse. IL informations presented by most makers will typically be based upon interpolation of the silencer into a standard piping system dwelling of specified consecutive tallies of shrieking before and after the silencer. Exhaust system constellations every bit good as mechanical design can hold a significant impact on the public presentation of and exhaust silencer and should be considered at the clip of specification. Raw exhaust noise degrees should be obtained from the engine maker to find the necessary noise decrease demands of the proposed silencer. Specific installing conditions and exhaust noise degrees will help the maker in finding the right silencer to run into the needed noise decrease

Mechanical public presentation – The Mechanical public presentation standard specifies the stuff belongingss of the fumes system to guarantee that it is lasting and requires small care when incorporated into service. Material choice is particularly of import in instances affecting high temperature or caustic gases. Traditional C steels will typically be sufficient for the bulk of applications utilizing Diesel fueled generators. Natural Gas engines will traditionally run at an elevated temperature above their Diesel opposite number, and may necessitate a ranked C or chromium steel steel that can keep an component of structural public presentation at elevated temperatures.

Aluminized steel is available from many silencer makers and is frequently preferred for general applications. Aluminized steel is somewhat more heat immune than C steel and offers an increased resilience to corrosion and is frequently selected as an economical option to stipulating a chromium steel steel system. Regular periodic testing of a standby generator will subject the fumes system to thermal rhythms that can lend to the premature corrosion of C steel

Aerodynamic performance- The Aerodynamic public presentation standard specifies the

maximal acceptable force per unit area bead through the silencer ( backpressure of the silencer ) . The exhaust flow rate and temperature from the engine maker are required to accurately foretell the backpressure of a silencer and piping system. Choice of an exhaust silencer based entirely on the diameter of the linking piping can frequently take to improperly selected merchandises that may show installing issues. Traditional caput loss computations using standardised coefficients for sudden contraction and enlargement of fluids can be used to come close the force per unit area bead through a silencer and combined with the values obtained for the balance of the piping system. More complex silencer internal constructions should be analyzed utilizing Computational Fluid Dynamics ( CFD ) where traditional empirical computations or premises may take to inaccurate consequences. The force per unit area bead through silencers should be obtained from the maker of the merchandise upon entry of the needed flow information.

Structural performance- The Structural public presentation standard can stipulate the geometric limitations and/or maximal allowable volume/weight of the silencer that can well act upon the silencer design procedure. Secondary lading exterior of the weight of the silencer can besides impact the design and cost of the fumes system. A standard engine silencer is non traditionally designed to absorb significant tonss due seismal activity, air current or thermic growing of next piping. Silencers that are specifically incorporated as an component of an exhaust “ stack ” should be designed to suit the tonss that will be absorbed due to potentially high air current tonss every bit good as seismal activity. A trade good purchased silencer should be isolated from significant piping tallies through the usage of flexible enlargement articulations to cut down or extinguish the transportation of tonss and engine quiver. Customized silencers can easy be designed when the force and minute values that can be placed on a connexion are indicated at the clip of citation.

Ch.5 DESIGN PARAMETERS

Adequate Insertion Loss – The chief map of a silencer is to smother sound. An effectual silencer will cut down the sound force per unit area of the noise beginning to the needed degree. In the instance of an automotive silencer the noise in the fumes system generated by the engine is to be reduced. A silencers public presentation or rarefying capableness is by and large defined in footings of interpolation loss or transmittal loss. Insertion loss is defined as the difference between the acoustic power radiated with out and with a silencer fitted. The transmittal loss Is defined as the between the sound force per unit area incident at the entry to the silencer to that transmitted by the silencer.

Desired sound Generally, a silencer is used to cut down sound of a burning engine to a desired degree that provides comfort for the driver and riders of the vehicle every bit good as minimising sound pollution to the environment. Muffler designs by and large aim to cut down any raging features of the untreated exhaust noise such as low frequence rumble.There has nevertheless been a turning tendency in Australia in recent old ages for immature drivers desiring to “ hot-up ” their vehicles and this includes muffler alteration. Muffler alteration of a stock vehicle is by and large done for two grounds being public presentation and sound. Vehicles leave the mill floor with silencers by and large designed for noise control non optimum public presentation. The standard reactive silencer is by and large replaced with a consecutive through soaking up silencer for aesthetics and to minimise backpressure and hence better vehicle public presentation.

Backpressure – Backpressure represents the excess inactive force per unit area exerted by the silencer on the engine through the limitation in flow of exhaust gasses By and large the better a silencer is at rarefying sound the more backpressure is generated. In a reactive silencer where good fading is achieved the fumes gasses are forced to go through through legion geometry alterations and a just sum of backpressure may be generated, which reduces the power end product of the engine. Backpressure should be kept to a lower limit to avoid power losingss particularly for public presentation vehicles where public presentation is paramount.

Every clip the fumes gasses are forced to alter way extra backpressure is created. Therefore to restrict backpressure geometric alterations are to be kept to a lower limit, a typical illustration of this is a “ consecutive through ” soaking up silencer. Exhaust gasses are allowed to go through virtually unimpeded through the consecutive perforated pipe.

Size -The available infinite has a great influence on the size and hence type of silencer that may be used. A silencer may hold its geometry designed for optimal fading nevertheless if it does non run into the infinite restraints, it is useless.Generally the larger a silencer is, the more it weighs and the more it costs to fabricate. For a public presentation vehicle every gm saved is important to its performance/acceleration, particularly when covering with light unfastened wheeled race vehicles. Therefore a little lightweight silencer is desirable. Efficaciously back uping a silencer is ever a design issue and the larger a silencer is the more hard it is to back up. A silencer ‘s mounting system non merely needs to back up the silencers weight but it besides needs to supply quiver isolation so that the quiver of the fumes system is non transferred to the human body and so to the rider cabin. This quiver isolation is normally achieved with the usage of difficult gum elastic inserts and brackets that isolate or dampen quiver from the silencer to the human body.

Durability The life anticipation of a silencer is another of import functional demand particularly when covering with hot fumes gasses and absorbent silencers that are found in public presentation vehicles. Overtime, hot fumes gasses tend to choke off the absorbent stuff with unburnt C atoms or fire the absorbent stuff in the silencer. This causes the interpolation loss to deteriorate. There are nevertheless, good merchandises such as mineral wool, fibreglass, sintered metal complexs and white wool that resist such unwanted effects. Reactive type silencers with no absorbent stuff are really lasting and their public presentation does non decrease with clip. Generally silencers are made from corrosion resistive stuffs such as unstained steel or aluminum. Mild steel or aluminised steel is by and large used for temperatures up to 500A°C, type 409 chromium steel steel up to 700 A°C and type 321 chromium steel steel for even higher temperatures. Automotive fumes gas temperatures are normally around 750 A°C.

Shape Automotive silencers come in all different forms, manners and sizes depending on the coveted application. By and large automotive silencers consist of an recess and mercantile establishment tubing separated by a larger chamber that is egg-shaped or unit of ammunition in geometry. The inside item of this larger chamber may be one of legion buildings. The terminal user of the silencer normally does non care what is indoors this chamber so long as the silencer produces the desired sound and is aesthetically delighting. It is hence the undertaking of the silencer interior decorator to guarantee that the silencer is functional every bit good as marketable.

Ch 5. Determination of primary pipe length

The informations used as a footing for pipe length are the length of gap of the exhaust valve in grades and the gas speed through the valve port ; as the latter can merely be calculated as an mean figure based on Piston velocity, a invariable is included to convey this nearer the awaited initial speed of gas at the minute of exhaust valve gap, when the cylinder force per unit area is high, as this starts the initial haste of gas down the pipe, after which there is some decelerating down.

Length of primary pipe ( pess ) =ASD2/2000d2

Where A = fumes valve opening period in grades of crankshaft rotary motion.

S = stroke length in inches

D = cylinder dullard in inches

vitamin D = exhaust valve port diameter in inches

2000 feet/min is the awaited initial speed of gas.

This expression should guarantee that the pipe, is sufficiently long to give a good moving ridge action, though it should `be borne in head that this will likely be most apparent at higher engine velocities in its consequence of torsion.

Primary Pipe length

A

A

A

A

A

A

A

A

assumed

calculated

A

EVO in grades

shot length ( inches )

cylinder dullard ( inches )

Exhaust valve Defense Intelligence Agency. In inches

Primary length ( pess )

P ( centimeter )

320

2.8

2.56

1.2

2.04

62.19

330

2.8

2.56

1.2

2.10

64.13

340

2.8

2.56

1.2

2.17

66.07

350

2.8

2.56

1.2

2.23

68.02

Pipe Diameter

The diameter of the primary pipes should be based on the dimensions of the valve expressway. However, it is obvious that the rim of the pipe has to fit up nicely with the exhaust-port face of the cylinder caput, it is usual for the external port to be instead larger in country than the existent valve pharynx, and it is non ever round in form but sometimes square or rectangular. Some interior decorators say that the somewhat increased country at this point is of benefit in cut downing force per unit area, peculiarly as there is frequently a crisp crook in the dramatis personae manifold bolted thereto. Three are reasonably simple methods of fiting up a unit of ammunition pipe subdivision to a square port, which will be detailed subsequently, but is desirable for the pipe proper to get down as close to the port as possible.

The valve pharynx diameter should be measured from the engine, unless it is included in the tabulated informations ; dimensions such as valve diameter are of small usage, as they can non be related to the former unless several other measurings are besides known. To let for boundary clash in the pipe, its internal diameter should be somewhat greater than the valve pharynx diameter, to the extent of A? inch lower limit. However, all these justnesss of dimensioning will hold to suit in with what is commercially available in the manner of tubing 6s. The appendix gives specifics of ordinary cold- drawn seamless steel tube of 15SWG holding a wall thickness of 0.072 inch. Extra high quality, aircraft type tube can be obtained, but is of course more expensive. Eighteen gage is likely the minimal thickness that should be used, if sensible life is to be obtained.

Tail pipe design

Exhaust tail pipe will hold resonances that can magnify engine tones and bring forth unwanted noise, to avoid elaboration of tones we use short tail pipe or size L to 1/4 wavelength ( l/4 )

Tail Pipe Resonances

fn = nc/ ( 2L )

where:

fn is resonance frequence of pipe

n = 1, 2, 3, aˆ¦

degree Celsius is speed of sound

L is length of pipe ( foot )

resonance occurs if L = nI»/2

preffered tail pipe length L = I»/4

Ch 6.Design Proposed

interior diameter of 36mm ; outer shell diameter of 112 millimeters ;

length of 100mm ( approx ) ; Perforated tubing running from the recess to the issue pipe with 120 perforations that are 1.2 millimeters in diameter. A bed of absorbent stuff is sandwiched between the perforated tubing and the outer shell.

Outer Dia of pipe is 3.8mm Inner Dia 3.6mm

P1 = 1.2bar

hafnium = FLV2 / 2gd ( head loss )

Section A-B. – Taking Pressure invariable At point A & A ; point B

A hafnium = 0.6 * 12 *17.222/ 2*9.8*3.6 = 30.25m

Bend Loss = V2/ 2g = 0.5 * 17.222/ 2*9.8 = 7.56

P1/??g + v12/??g = P2/??g + V22/2g + hafnium + Bend Loss

A

( 1.2 * 105/1.2 *9.8 ) + ( 17.222 / 2*9.8 ) = ( 1.2 * 105/1.2 *9.8 ) + V22/2*9.8 + 30.25 +7.56

A

V2 = 16.09 m/s

A Section B-C – Pressure is Drop is considered.

hafnium = 0.6 * 32 *16.092/ 2*9.8*3.6 = 70.44 m

P1/??g + v12/??g = P2/??g + V22/2g + hafnium

( 1.2 * 105/1.2 * 9.8 ) + ( 16.092 / 2*9.8 ) = ( 1.17 * 105/1.2 *9.8 ) + V22/2*9.8 + 70.44

V2 = 62.45 m/s

Section C-D

hafnium = 0.6 * 10 *62.452/ 2*9.8*3.6 = 329.51 m

P1/??g + v12/??g = P2/??g + V22/2g + hafnium

( 1.2 * 105/1.2 * 9.8 ) + ( 62.252 / 2*9.8 ) = ( 1.14 * 105/1.2 *9.8 ) + V22/2*9.8 + 329.51

A V2 = 81.50 m/s

Using the undermentioned relation*

0.5 ( 49.03a?sA°R ) /2Iˆfa‰¤La‰¤2.6 ( 49.03a?sA°R ) /2Iˆf

Temp of exhaust = 700 A°C or 700 * 0.8 = 560 R

Frequency = 270 Hz

e 0.5 ( 49.03a?sA°560 ) /2Iˆ*270a‰¤La‰¤2.6 ( 49.03a?sA°560 ) /2Iˆ*270

0.3 ft a‰¤ L a‰¤ 1.3Ft

Length of Mufller we have proposed = 42cm

Ch7. Observation & A ; Findingss

Piston Speed = stroke length x revolutions per minute / 6

Gas velocity = ( piston velocity ten ( Cyl. Dia ) 2 ) / ( larboard Defense Intelligence Agency ) 2

Gas Speed at assorted engine velocity

A

A

A

A

A

A

A

A

calculated

A

assumed

calculated

A

shot length in inches

Revolutions per minute

Piston velocity ( feet/min )

cyl. Dia

port Defense Intelligence Agency.

gas velocity ( feet/min )

gas velocity ( m/s )

2.4

1400

560

3.1

1.26

3389.77

17.22

2.4

1500

600

3.1

1.26

3631.90

18.45

2.4

1600

640

3.1

1.26

3874.02

19.68

2.4

1700

680

3.1

1.26

4116.15

20.91

2.4

1800

720

3.1

1.26

4358.28

22.14

2.4

1900

760

3.1

1.26

4600.40

23.37

2.4

2000

800

3.1

1.26

4842.53

24.60

2.4

2100

840

3.1

1.26

5084.66

25.83

2.4

2200

880

3.1

1.26

5326.78

27.06

2.4

2300

920

3.1

1.26

5568.91

28.29

2.4

2400

960

3.1

1.26

5811.04

29.52

2.4

2500

1000

3.1

1.26

6053.16

30.75

2.4

2600

1040

3.1

1.26

6295.29

31.98

2.4

2700

1080

3.1

1.26

6537.41

33.21

2.4

2800

1120

3.1

1.26

6779.54

34.44

2.4

2900

1160

3.1

1.26

7021.67

35.67

2.4

3000

1200

3.1

1.26

7263.79

36.90

2.4

4000

1600

3.1

1.26

9685.06

49.20

2.4

4100

1640

3.1

1.26

9927.19

50.43

2.4

4200

1680

3.1

1.26

10169.31

51.66

2.4

4300

1720

3.1

1.26

10411.44

52.89

2.4

4400

1760

3.1

1.26

10653.57

54.12

2.4

4500

1800

3.1

1.26

10895.69

55.35

2.4

4600

1840

3.1

1.26

11137.82

56.58

2.4

4700

1880

3.1

1.26

11379.94

57.81

2.4

4800

1920

3.1

1.26

11622.07

59.04

2.4

4900

1960

3.1

1.26

11864.20

60.27

2.4

5000

2000

3.1

1.26

12106.32

61.50

2.4

5100

2040

3.1

1.26

12348.45

62.73

2.4

5200

2080

3.1

1.26

12590.58

63.96

2.4

5300

2120

3.1

1.26

12832.70

65.19

2.4

5400

2160

3.1

1.26

13074.83

66.42

2.4

5500

2200

3.1

1.26

13316.96

67.65

2.4

5600

2240

3.1

1.26

13559.08

68.88

2.4

5700

2280

3.1

1.26

13801.21

70.11

2.4

5800

2320

3.1

1.26

14043.34

71.34

A

A

A

A

A

A

A

A

A

A

A

A

A

A

shot length in inches

Revolutions per minute

Piston velocity ( feet/min )

cyl. Dia

port Defense Intelligence Agency.

gas velocity ( feet/min )

gas velocity ( m/s )

2.4

1400

560

3.1

1.3

3184.38

16.18

2.4

1500

600

3.1

1.3

3411.83

17.33

2.4

1600

640

3.1

1.3

3639.29

18.49

2.4

1700

680

3.1

1.3

3866.75

19.64

2.4

1800

720

3.1

1.3

4094.20

20.80

2.4

1900

760

3.1

1.3

4321.66

21.95

2.4

2000

800

3.1

1.3

4549.11

23.11

2.4

2100

840

3.1

1.3

4776.57

24.26

2.4

2200

880

3.1

1.3

5004.02

25.42

2.4

2300

920

3.1

1.3

5231.48

26.58

2.4

2400

960

3.1

1.3

5458.93

27.73

2.4

2500

1000

3.1

1.3

5686.39

28.89

2.4

2600

1040

3.1

1.3

5913.85

30.04

2.4

2700

1080

3.1

1.3

6141.30

31.20

2.4

2800

1120

3.1

1.3

6368.76

32.35

2.4

2900

1160

3.1

1.3

6596.21

33.51

2.4

3000

1200

3.1

1.3

6823.67

34.66

2.4

4000

1600

3.1

1.3

9098.22

46.22

2.4

4100

1640

3.1

1.3

9325.68

47.37

2.4

4200

1680

3.1

1.3

9553.14

48.53

2.4

4300

1720

3.1

1.3

9780.59

49.69

2.4

4400

1760

3.1

1.3

10008.05

50.84

2.4

4500

1800

3.1

1.3

10235.50

52.00

2.4

4600

1840

3.1

1.3

10462.96

53.15

2.4

4700

1880

3.1

1.3

10690.41

54.31

2.4

4800

1920

3.1

1.3

10917.87

55.46

2.4

4900

1960

3.1

1.3

11145.33

56.62

2.4

5000

2000

3.1

1.3

11372.78

57.77

2.4

5100

2040

3.1

1.3

11600.24

58.93

2.4

5200

2080

3.1

1.3

11827.69

60.08

2.4

5300

2120

3.1

1.3

12055.15

61.24

2.4

5400

2160

3.1

1.3

12282.60

62.40

2.4

5500

2200

3.1

1.3

12510.06

63.55

2.4

5600

2240

3.1

1.3

12737.51

64.71

2.4

5700

2280

3.1

1.3

12964.97

65.86

2.4

5800

2320

3.1

1.3

13192.43

67.02

Intake airflow = ( Engine size x RPM x 3456 ) / volumetric efficiency

Exhaust Flow rate = ( ( Exhaust temperature + 460 ) / 540 ) x Intake air flow

consumption air flow

A

A

A

A

A

A

A

A

A

assumed

calculated

A

A

calculated

A

engine size ( CID )

Revolutions per minute

volumetric efficiency

consumption air flow ( CFM )

consumption air flow ( m^3/hour )

exhaust temprature ( degree F )

exhaust flow rate ( CFM )

exhaust flow rate ( m^3/hour )

43.2

3000

0.8

30.00

50.87

1740

122.22

206.56

43.2

3100

0.8

31.00

52.56

1740

126.30

213.44

43.2

3200

0.8

32.00

54.26

1740

130.37

220.33

43.2

3300

0.8

33.00

55.95

1740

134.44

227.21

43.2

3400

0.8

34.00

57.65

1740

138.52

234.10

43.2

3500

0.8

35.00

59.35

1740

142.59

240.98

43.2

3600

0.8

36.00

61.04

1740

146.67

247.87

43.2

3700

0.8

37.00

62.74

1740

150.74

254.75

43.2

3800

0.8

38.00

64.43

1740

154.81

261.64

43.2

3900

0.8

39.00

66.13

1740

158.89

268.52

43.2

4000

0.8

40.00

67.82

1740

162.96

275.41

43.2

4100

0.8

41.00

69.52

1740

167.04

282.29

43.2

4200

0.8

42.00

71.22

1740

171.11

289.18

43.2

4300

0.8

43.00

72.91

1740

175.19

296.06

43.2

4400

0.8

44.00

74.61

1740

179.26

302.95

43.2

4500

0.8

45.00

76.30

1740

183.33

309.83

43.2

4600

0.8

46.00

78.00

1740

187.41

316.72

43.2

4700

0.8

47.00

79.69

1740

191.48

323.60

43.2

4800

0.8

48.00

81.39

1740

195.56

330.49

43.2

4900

0.8

49.00

83.08

1740

199.63

337.37

43.2

5000

0.8

50.00

84.78

1740

203.70

344.26

43.2

5100

0.8

51.00

86.48

1740

207.78

351.14

43.2

5200

0.8

52.00

88.17

1740

211.85

358.03

43.2

5300

0.8

53.00

89.87

1740

215.93

364.91

43.2

5400

0.8

54.00

91.56

1740

220.00

371.80

43.2

5500

0.8

55.00

93.26

1740

224.07

378.69

43.2

5600

0.8

56.00

94.95

1740

228.15

385.57

43.2

5700

0.8

57.00

96.65

1740

232.22

392.46

43.2

5800

0.8

58.00

98.34

1740

236.30

399.34

43.2

5900

0.8

59.00

100.04

1740

240.37

406.23

43.2

6000

0.8

60.00

101.74

1740

244.44

413.11

43.2

6100

0.8

61.00

103.43

1740

248.52

420.00

43.2

6200

0.8

62.00

105.13

1740

252.59

426.88

43.2

6300

0.8

63.00

106.82

1740

256.67

433.77

43.2

6400

0.8

64.00

108.52

1740

260.74

440.65

43.2

6500

0.8

65.00

110.21

1740

264.81

447.54

43.2

6600

0.8

66.00

111.91

1740

268.89

454.42

43.2

6700

0.8

67.00

113.61

1740

272.96

461.31

43.2

6800

0.8

68.00

115.30

1740

277.04

468.19

43.2

6900

0.8

69.00

117.00

1740

281.11

475.08

43.2

7000

0.8

70.00

118.69

1740

285.19

481.96

43.2

7100

0.8

71.00

120.39

1740

289.26

488.85

43.2

7200

0.8

72.00

122.08

1740

293.33

495.73

43.2

7300

0.8

73.00

123.78

1740

297.41

502.62

43.2

7400

0.8

74.00

125.47

1740

301.48

509.50

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

engine size ( CID )

A

assumed

calculated

A

A

calculated

A

43.3

Revolutions per minute

volumetric efficiency

consumption air flow ( CFM )

consumption air flow ( m^3/hour )

exhaust temprature ( degree F )

exhaust flow rate ( CFM )

exhaust flow rate ( m^3/hour )

43.3

3000

0.83

31.20

52.90

1740

127.10

214.80

43.3

3100

0.83

32.24

54.66

1740

131.34

221.96

43.3

3200

0.83

33.28

56.42

1740

135.57

229.12

43.3

3300

0.83

34.32

58.19

1740

139.81

236.28

43.3

3400

0.83

35.36

59.95

1740

144.05

243.44

43.3

3500

0.83

36.40

61.71

1740

148.28

250.60

43.3

3600

0.83

37.44

63.48

1740

152.52

257.76

43.3

3700

0.83

38.48

65.24

1740

156.76

264.92

43.3

3800

0.83

39.52

67.00

1740

160.99

272.08

43.3

3900

0.83

40.56

68.77

1740

165.23

279.24

43.3

4000

0.83

41.60

70.53

1740

169.47

286.40

43.3

4100

0.83

42.64

72.29

1740

173.70

293.56

43.3

4200

0.83

43.68

74.06

1740

177.94

300.72

43.3

4300

0.83

44.72

75.82

1740

182.18

307.88

43.3

4400

0.83

45.76

77.58

1740

186.41

315.04

43.3

4500

0.83

46.80

79.35

1740

190.65

322.20

43.3

4600

0.83

47.84

81.11

1740

194.89

329.36

43.3

4700

0.83

48.88

82.87

1740

199.12

336.52

43.3

4800

0.83

49.92

84.64

1740

203.36

343.68

43.3

4900

0.83

50.96

86.40

1740

207.60

350.84

43.3

5000

0.83

52.00

88.16

1740

211.83

358.00

43.3

5100

0.83

53.03

89.93

1740

216.07

365.16

43.3

5200

0.83

54.07

91.69

1740

220.31

372.32

43.3

5300

0.83

55.11

93.45

1740

224.54

379.48

43.3

5400

0.83

56.15

95.22

1740

228.78

386.64

43.3

5500

0.83

57.19

96.98

1740

233.01

393.80

43.3

5600

0.83

58.23

98.74

1740

237.25

400.96

43.3

5700

0.83

59.27

100.51

1740

241.49

408.12

43.3

5800

0.83

60.31

102.27

1740

245.72

415.28

43.3

5900

0.83

61.35

104.03

1740

249.96

422.43

43.3

6000

0.83

62.39

105.80

1740

254.20

429.59

43.3

6100

0.83

63.43

107.56

1740

258.43

436.75

43.3

6200

0.83

64.47

109.32

1740

262.67

443.91

43.3

6300

0.83

65.51

111.09

1740

266.91

451.07

43.3

6400

0.83

66.55

112.85

1740

271.14

458.23

43.3

6500

0.83

67.59

114.61

1740

275.38

465.39

43.3

6600

0.83

68.63

116.37

1740

279.62

472.55

43.3

6700

0.83

69.67

118.14

1740

283.85

479.71

43.3

6800

0.83

70.71

119.90

1740

288.09

486.87

43.3

6900

0.83

71.75

121.66

1740

292.33

494.03

43.3

7000

0.83

72.79

123.43

1740

296.56

501.19

43.3

7100

0.83

73.83

125.19

1740

300.80

508.35

43.3

7200

0.83

74.87

126.95

1740

305.04

515.51

43.3

7300

0.83

75.91

128.72

1740

309.27

522.67

A

7400

0.83

76.95

130.48

1740

313.51

529.83

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

A

engine size ( CID )

A

assumed

calculated

A

A

calculated

A

43.3

Revolutions per minute

volumetric efficiency

consumption air flow ( CFM )

consumption air flow ( m^3/hour )

exhaust temprature ( degree F )

exhaust flow rate ( CFM )

exhaust flow rate ( m^3/hour )

43.3

3000

0.85

31.95

54.17

1740

130.16

219.97

43.3

3100

0.85

33.01

55.98

1740

134.50

227.31

43.3

3200

0.85

34.08

57.78

1740

138.84

234.64

43.3

3300

0.85

35.14

59.59

1740

143.18

241.97

43.3

3400

0.85

36.21

61.40

1740

147.52

249.30

43.3

3500

0.85

37.27

63.20

1740

151.86

256.64

43.3

3600

0.85

38.34

65.01

1740

156.19

263.97

43.3

3700

0.85

39.40

66.81

1740

160.53

271.30

43.3

3800

0.85

40.47

68.62

1740

164.87

278.63

43.3

3900

0.85

41.53

70.42

1740

169.21

285.97

43.3

4000

0.85

42.60

72.23

1740

173.55

293.30

43.3

4100

0.85

43.66

74.04

1740

177.89

300.63

43.3

4200

0.85

44.73

75.84

1740

182.23

307.96

43.3

4300

0.85

45.79

77.65

1740

186.57

315.30

43.3

4400

0.85

46.86

79.45

1740

190.90

322.63

43.3

4500

0.85

47.92

81.26

1740

195.24

329.96

43.3

4600

0.85

48.99

83.06

1740

199.58

337.29

43.3

4700

0.85

50.05

84.87

1740

203.92

344.62

43.3

4800

0.85

51.12

86.68

1740

208.26

351.96

43.3

4900

0.85

52.18

88.48

1740

212.60

359.29

43.3

5000

0.85

53.25

90.29

1740

216.94

366.62

43.3

5100

0.85

54.31

92.09

1740

221.27

373.95

43.3

5200

0.85

55.38

93.90

1740

225.61

381.29

43.3

5300

0.85

56.44

95.70

1740

229.95

388.62

43.3

5400

0.85

57.51

97.51

1740

234.29

395.95

43.3

5500

0.85

58.57

99.32

1740

238.63

403.28

43.3

5600

0.85

59.64

101.12

1740

242.97

410.62

43.3

5700

0.85

60.70

102.93

1740

247.31

417.95

43.3

5800

0.85

61.77

104.73

1740

251.65

425.28

43.3

5900

0.85

62.83

106.54

1740

255.98

432.61

43.3

6000

0.85

63.90

108.34

1740

260.32

439.95

43.3

6100

0.85

64.96

110.15

1740

264.66

447.28

43.3

6200

0.85

66.03

111.96

1740

269.00

454.61

43.3

6300

0.85

67.09

113.76

1740

273.34

461.94

43.3

6400

0.85

68.16

115.57

1740

277.68

469.28

43.3

6500

0.85

69.22

117.37

1740

282.02

476.61

43.3

6600

0.85

70.29

119.18

1740

286.36

483.94

43.3

6700

0.85

71.35

120.98

1740

290.69

491.27

43.3

6800

0.85

72.42

122.79

1740

295.03

498.61

43.3

6900

0.85

73.48

124.60

1740

299.37

505.94

43.3

7000

0.85

74.55

126.40

1740

303.71

513.27

43.3

7100

0.85

75.61

128.21

1740

308.05

520.60

43.3

7200

0.85

76.68

130.01

1740

312.39

527.94

43.3

7300

0.85

77.74

131.82

1740

316.73

535.27

7400

0.85

78.81

133.63

1740

321.07

542.60

Ch 8. Approach utilizing CFD & A ; Gambit

Making geometry in Gambit

Open Gambit and choose the Working Directory.

Travel to Operation Toolbar -Geometry Command Button -Vertex bid – Enter all the Vertex separately.

For pipe Structure.

A ( 0,0,0 ) ; B ( 0,0.12,0 ) ; C ( .036, .12,0 ) ; D ( 0.36,0.36,0 ) ; E ( 0.32,0.36,0 ) ; F ( 0.32,0,0 ) ; G ( .3907, .1067,0 ) ; H ( .3907, .0707,0 )

For Muffler

A ( 0,0,0 ) , B ( 0.06,0,0 ) , C ( 0,0.036,0 ) , D ( .06, .036,0 ) , E ( .06,0.56,0 ) , F ( 0.06, -0.56,0 ) , G ( 0.46,0.56,0 ) , H ( 0,0.46,0 ) , I ( 0.46, 0.036,0 ) , J ( 0.52,0,0 ) , K ( 0.52,0.036,0 )

( *We are making individually for Pipe individually for Muffler )

Travel to Operation Toolbar – Geometry Command Button -Vertex bid – Edge Command button- Join all the borders in the coveted form for both pipe & A ; silencer.

Travel to Operation Toolbar -Geometry Command Button -Face bid -Create Face.

Operation toolbar- Mesh Command button- Edge Command button- Select the edges- give the interval count- chink apply

Operation toolbar- Mesh Command button- Face bid button- Mesh face- select the face- chink apply

Operation toolbar-Zone bid button- Specify boundary types command button

For pipe

Pipe left recess

Velocity recess

Pipe right mercantile establishment

Pressure Mercantile establishment

Rest all borders

Wall

File – save

File- export- Check export to 2D mesh

Exit

Set up job in fluent

Open the Fluent – Select 2ddp – chink tally

fig.4

Travel to file- read instance – Read the.msh file

Travel to Grid- Check

Grid – Info- Size

Define- stuff – Problem solver

Solver- Pressure Based and infinite – 2D

Define- Model- uncheck the Energy

Define- theoretical account – Viscous- K- epsilon

Click apply

Define boundary status

Define runing status

In operating status

Set the recess speed and besides look into all the boundary status are same as ploy or non

Solve – Control – Solution- alteration Momentum, Turbulent Kinetics Energy & A ; Turbulent Dissipation to Second Order Upwind- Click use

Solve – initialize – Initialize

Select in compute the Inlet

Click init so use so near

Solve- Monitor- remainder

Check secret plan

Change the absolute Criteria to 1e-6 for Residual

Click Oklahoma

Solve Iterate

No of loop 500

Display Vectors

Display Contour

Select Contour of force per unit area, speed, turbulency, Wall shear emphasis

For Pipe

Velocity vectors Of Velocity magnitude

Contours of Turbulent Kinetic Energy

Contours of Inactive Pressure

Iteration Curve

Contours of speed magnitude

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