Hascon's Model Ling Canopy-Fumes Simulation.pdf.PDF

Hascon Engineering S.p.A. Page 1

Thermal-fluid dynamic analysis of an environment containing a furnace by

HASCON ENGINEERING S.p.A.

DATE OF FIRST ISSUE : 25 Ottobre 2012


List of page issue

Page FR TO AND FRO TO

Rev.0 1 25


Rev.1 1 24


Rev. 2

REVISIONI

Rev. DATE DESCRIPTION SIGNATURE 0 03/11/2011 Thermal-fluid dynamic analysis of an

environment containing a furnace by HASCON ENGINEERING S.p.A.

1 25/10/2012 Modify the previous report to

consider the new solution hood


TABLE OF CONTENTS-TOPICS

TITLE Pag.

List of Issues 2

Revisions 2

Distribution list 2

Table of contents 3

Introduction 4

Preparation of the geometric and fluidynamic model 4

Presentation of the results 13

Chart of summarized results 20

Conclusions 24


INTODUCTION

This thermal-fluidynamic analysis report has been done to check the sizing of the suction system of a steel production plant that include an EAF, furnace,(that produces fume), in two different lay-out condition qualified “CHARGING e TAPPING”. CHARGING: charging operation of the furnace with basket carried by the crane TAPPING: casting operation from the furnace to the ladle below The numerical analyses have been carried out by using a fluidynamic module of the SIMULATION calculation code, in its FLOW SIMULATION 2012. The model was prepared in a SOLIDWORKS 2012.

Product Flow Simulation 2012 5.0

Computer name EXPENG

User name EXPENG

Processors Intel(R) Core(TM) i7-2930QM CPU @

2.80GHz

Memory 8139 MB / 8388607 MB

Operating system Service Pack 1 (Build 7601)

CAD version SolidWorks 2012 SP5.0

CPU speed 2801 MHz

PREPARATION OF THE GEOMETRIC AND FLUIDYNAMIC MODEL The geometric models have been generated from the three-dimensional models in neutral “step” format supplied from “HASCON ENGINEERING SPA” and by eliminating and simplifying the outer components that do not concern the phenomenon. Current configuration of the hood and of the suction ducts is the result of an evolution of intermediate models optimized analysis

Fig. 1 – Hascon model


The THERMAL-FLUIDYNAMIC analysis carried out with the FLOW SIMULATION calculation program allows to determine the distribution of the temperatures, the velocity, the pressures, and the densities (in addition to all the other characteristic dimensions) of both a sealed and open system, given stationary or transitory surrounding conditions. The analysis wants to simulate and compare an open and re-sealed furnace condition and the subsequent conditions of the surrounding environment, determined by the suction system of the production plant that hosts the furnace. Given the same outer geometries, the furnace will be opened and sealed again in 30 seconds, and the exhaust smoke first will be captured outside the hood and than eliminated by two parallel ducts positioned at about half the height of the hood and having 12 nozzles lower and 2 upper each.

The suction flow capacity of the pipelines is 1.005.128 m3/h for all the solutions analyzed. (Charging and Tapping). Suction will be steady over the entire length of the transitory analysis. The plant has different openings, and wind effect has been considered on the outside.

The analytical check thus proves to have an open domain limited by the BOX shown in figures 1, 2, and 3. CHARGING:. On the upper surface of the oven have been applied the conditions of the incoming

stream of smoke. The temporal law that governs smoke outflow has been imposed with a trapezoidal progress, such that the maximum production of smoke is reached in 2 seconds (5m/s in outlet from the furnace surface) in the following 26 seconds, the maximum smoke production is maintained steady, and in the 2 seconds that follow, smoke production is zeroed. The analysis will be protracted for a total 90 seconds, even if the instant time of


greatest interest for the engineering and solution comparison purposes will be 28s. The following chart displays the conditions of "smoke" production: Dependencies

Table #1

Velocity normal to face

Boundary Conditions/Inlet Velocity 1/Flow parameters/Velocity normal to face

Table #2

Temperature

Boundary Conditions/Inlet Velocity 1/Thermodynamic parameters/Temperature

Curve of the smoke production

. TAPPING: the same conditions imposed for the CHARGING have been imposed on the bottom

surface of the ladle and on the surfaces of the "beak" of the furnace. Being fixed speeds, ranges depend on the extent of surfaces. The condition of Tapping is thus produce a mass of smoke significantly lower compared to the condition of Charging


Fig. 2 – sorrounding conditions

The temperature of the smoke has been set at 780°c during the time in which the furnace is open. This temperature was obtained in an empirical manner by seeking the convergence of the outlet temperature of the fumes than reported by the report of smoke analysis. The use of a new type of Hascon’s canopy model and "smoke-Hascon" fluid has allowed to follow its evolution of the "fume" dimension generated, during and after furnace opening. The total analysis time has been set at 90 seconds, and the characteristic fluodynamic values have been memorized at 6, 28, and 44 second for the condition of CHARGING and TAPPING. The initial temperature of the plant and of the outer environment have been set at 20.1°C.


The following surrounding conditions have been applied for all three models:

Initial Conditions

Thermodynamic parameters Static Pressure: 101325 Pa

Temperature: 20.1 °C

Velocity parameters Velocity vector

Velocity in X direction: -1.4 m/s

Velocity in Y direction: 1.4 m/s

Velocity in Z direction: 0 m/s

Concentrations Substance fraction by mass

Air

1.00

Fumo-Hascon

0

Turbulence parameters Turbulence intensity and length

Intensity: 0.100 %

Length: 0.638 m

Physical Features

Heat conduction in solids: Off

Time dependent: On

Gravitational effects: On

Flow type: Laminar and turbulent

High Mach number flow: Off

Humidity: Off

Default roughness: 0 micrometer

Gravitational Settings

X component 0 m/s^2

Y component 0 m/s^2

Z component -9.8 m/s^2

Computational Domain

Size

X min -40000.000 mm

X max 105000.000 mm

Y min -120000.000 mm

Y max 55000.000 mm

Z min -10000.000 mm

Z max 56000.000 mm

The discretization used for the fluodynamic analysis (MESH) is the one defined as "with finished volumes" of Cartesian type. With an automatic algorithm, the program determines the most critical areas and volumes (geometric or fluidynamic variations) and intervenes by densifying the mesh elements.


Calculation Mesh

Basic Mesh Dimensions (all models)

Number of cells in X 38

Number of cells in Y 43

Number of cells in Z 17

Number Of Cells

Total cells 1458725

Fluid cells 930716

Solid cells 112034

Partial cells 415975

Irregular cells 0

Trimmed cells 55781

Fig. 3-mesh

The convergence parameters are defined as Goals and have been set so as to make the program search an optimal stability of the results. Increasing the value of the convergence analysis will be faster and less precise, conversely, decreasing these parameters will increase precision and resolution times.

Goals

Surface Goals

SG Mass Flow Rate of Fumo-Hascon 1

Type Surface Goal

Goal type Mass Flow Rate of HASCON Fumes

Faces Fumes Exit

Coordinate system Global coordinate system

Use in convergence On: convergence value 0.2kg/s

SG Av Temperature of Fluid 1


Type Surface Goal

Goal type Temperature of Fluid

Calculate Average value

Faces Fumes Exit

Coordinate system Global coordinate system

Use in convergence On: convergence value 1°C

It is therefore based on the precision of the analysis parameters of mass of smoke output by the aspiration and the corresponding temperature of the smoke

Gases

Air

Path: Gases Pre-Defined

Specific heat ratio (Cp/Cv): 1.399

Molecular mass: 0.0290 kg/mol

Dynamic viscosity

0

0.00002

0.00004

0.00006

0.00008

0.0001

0.00012

-500 0 500 1000 1500 2000 2500 3000

Temperature[°C]

Dyn

am

ic v

isco

sit

y[P

a*s

]

Specific heat (Cp)

0

500

1000

1500

2000

2500

3000

3500

-500 0 500 1000 1500 2000 2500 3000

Temperature[°C]

Sp

ecif

ic h

eat

(Cp

)[J/(

kg

*K)]


Thermal conductivity

0

0.1

0.2

0.3

0.4

0.5

0.6

-500 0 500 1000 1500 2000 2500 3000

Temperature[°C]

Th

erm

al co

nd

ucti

vit

y[W

/(m

*K)]

Hascon Fumes

Path: Gases User Defined

Specific heat ratio (Cp/Cv): 1.34

Molecular mass: 0.03 kg/mol

Dynamic viscosity

0

0.00002

0.00004

0.00006

0.00008

0.0001

0.00012

-500 0 500 1000 1500 2000 2500 3000

Dyn

amic

vis

cosi

ty[P

a*s]

Temperature[°C]

Specific heat (Cp)

0

500

1000

1500

2000

2500

3000

3500

-500 0 500 1000 1500 2000 2500 3000

Spe

cifi

c h

eat

(C

p)[

J/(k

g*K

)]

Temperature[°C]


Thermal conductivity

0

0.1

0.2

0.3

0.4

0.5

0.6

-500 0 500 1000 1500 2000 2500 3000

The

rmal

co

nd

uct

ivit

y[W

/(m

*K)]

Temperature[°C]


PRESENTATION OF THE RESULTS

The following images will be presented on the values of the variables obtained agreed as significant. The images show the "Mass Fraction of Fumes-Hascon" according to two perpendicular planes, one passing through the axis of the main intake duct and one passing through the axis of the furnace. In the condition of CHARGING and TAPPING images will show the state of distribution of smoke in the instants of 6, 28.44 seconds. The tests are performed, however, in all the moments of time 0s 90s at the time. NOTE The "Mass Fraction of Fumes-Hascon" represents the gas fraction created as FUMES-HASCON compared to the air. Value 1 of this dimension implies the presence of 100% of the fume mass in the point considered Pay attention to the scales applied to show the development of the smoke and evidential its evolution. CORRECTED VALUES are expressed by the numerical summary tables.


Fig. 4 – CHARGING Model - Seconds 6 NOTE: scale set to maximum to 0.2


Fig. 5 - CHARGING Model - Seconds 28


NOTE: : scale set to maximum to 0.2

Fig. 6 - CHARGING Model - Seconds 44

NOTA: scale set to maximum a 0.2



Fig. 7 - TAPPING Model- Seconds 6

Fig. 8 - TAPPING Model- Seconds 28

NOTE: scale set to maximum to 0.2


Fig. 9 - TAPPING Model- Seconds 44 NOTA: scale set to maximum a 0.01


Numerical comparison of the performance

CHARGING

Charging

Time [s]

in Mass Fraction of Fumes-Hascon [kg]

out Mass Fraction of Fumes-Hascon [kg]

0 0 0

2 302.8956197 -2.80031E-28

4 478.8846446 -1.81006E-14

6 644.9719212 -1.472964373

8 810.3403266 -4.140315499

10 975.616582 -20.91474611

12 1140.873574 -56.57622721

14 1306.118094 -105.5372092

16 1471.357464 -161.3843563

18 1636.601438 -225.4785004

20 1801.848574 -296.2682727

22 1967.10468 -372.3675928

24 2132.391278 -453.0923381

26 2297.687098 -537.9065122

28 2462.976431 -626.1221916

30 2467.85 -717.5075987

32 2467.85 -811.20488

34 2467.85 -905.7946303

36 2467.85 -998.7068811

38 2467.85 -1090.351481

40 2467.85 -1180.858627

42 2467.85 -1267.593347

44 2467.85 -1351.006245

46 2467.85 -1430.77321

48 2467.85 -1506.807782

50 2467.85 -1579.677494

52 2467.85 -1648.826663

54 2467.85 -1713.869867

56 2467.85 -1775.305969

58 2467.85 -1833.567961

60 2467.85 -1888.14024

62 2467.85 -1938.92007

64 2467.85 -1986.049735

66 2467.85 -2029.529234

68 2467.85 -2069.358567

70 2467.85 -2105.537735

72 2467.85 -2138.066737

74 2467.85 -2166.945574

76 2467.85 -2192.174245

78 2467.85 -2213.75275

80 2467.85 -2231.68109

82 2467.85 -2245.959264

84 2467.85 -2256.587273

86 2467.85 -2263.565116

88 2467.85 -2266.892793

90 2467.85 -2266.570305


TAPPING: BEHAVIOR DIFFERENCES BETWEEN PRODUCT AND USED PRODUCT FUMP


Numerical comparison of the performance TAPPING

Taping

Time [s]

in Mass Fraction of Fumes-Hascon

[kg]

out Mass Fraction of Fumes-Hascon [kg]

0 0 0

2 63.74006304 7.69982E-51

4 113.6729707 1.07476E-33

6 159.5523823 2.29012E-15

8 204.2380931 -9.63058E-05

10 248.5420411 -1.095403768

12 292.7379832 -4.685587111

14 336.8698468 -14.69646191

16 380.9530981 -28.68645341

18 425.0226934 -45.46300524

20 469.0828394 -67.05883679

22 513.1446389 -93.45574464

24 557.2133221 -123.014501

26 601.2786524 -154.9780314

28 603.44 -188.8528112

30 603.44 -224.5638972

32 603.44 -262.043472

34 603.44 -301.0799451

36 603.44 -341.0805808

38 603.44 -381.2812806

40 603.44 -420.904401

42 603.44 -458.8430676

44 603.44 -494.1141241

46 603.44 -526.1856225

48 603.44 -555.0961325

50 603.44 -581.6713861

52 603.44 -602.3276464

54 603.44 -602.3276464

56 603.44 -602.3276464

58 603.44 -602.3276464

60 603.44 -602.3276464

62 603.44 -602.3276464

64 603.44 -602.3276464

66 603.44 -602.3276464

68 603.44 -602.3276464

70 603.44 -602.3276464

72 603.44 -602.3276464

74 603.44 -602.3276464

76 603.44 -602.3276464

78 603.44 -602.3276464

80 603.44 -602.3276464

82 603.44 -602.3276464

84 603.44 -602.3276464

86 603.44 -602.3276464

88 603.44 -602.3276464

90 603.44 -602.3276464


TAPPING-BEHAVIOR DIFFERENCES BETWEEN PRODUCT AND USED PRODUCT PUMP


CONCLUSIONS

The fluid dynamic analysis show that the current solution of hood able to pick up 92% of the smoke generated in a time of 90 seconds for the phenomenon of charging and 99.8% for that of Tapping. The performance of the vacuum curves during Charging show a trend still positive values interrupted 90s at the time and this implies that to proceed for a longer time, the values of mass aspirated smoke would have increased the value of improving the efficiency of the proposed solution . The graphic images instead show that there is no smoke that escapes to the suction hood and its ducts.

Documents

Hascon's Model Ling Canopy-Fumes Simulation.pdf.PDF