Face Ventilation System Analysis and Design with help of CFD simulations

NIOSH Ventilation Meeting

Todor Petrov, Graduate Student, Mining Department, University of Kentucky

NIOSH Grant 2000 - 2009

Outline• About myself• Objectives• Classes completed• Research performed• Results of the conducted research study

– Validation of SC/Tetra CFD code using PIV measurements of 1:15 scaled physical model

– Validation of SC/Tetra CFD code using airflow and methane measurements collected during experiments conducted in NIOSH Ventilation Gallery with equipment free face area

– Validation of SC/Tetra CFD code using airflow and methane measurements collected during benchmark experiments conducted in NIOSH Ventilation Gallery with a continuous miner equipped with a scrubber

– CFD simulations of face ventilation applying original geometry of JOY14CM15 continuous miner

• Future work

About myselfEDUCATION

• University of Kentucky– PHD Student

• University of Mining and Geology, Sofia, Bulgaria– MSc in Mining Engineering, specialization Underground Mining– Postgraduate: Computer Technologies, Information and Control

Systems

EXPERIENCE• University of Mining and Geology, Sofia, Bulgaria

– Assistant Professor in Mine Ventilation and Safety– R&D Engineer at UMG Research Institute

Classes completed

• Advanced Mine Ventilation (MNG 641)• Topics in Mining Engineering - Blasting (MNG 699)• Seminar in Mining Engineering (MNG 771)• Advanced Control System Analysis (ME 645)• Scale Modeling (ME 565)• Combustion Phenomena (ME 536)• Numerical Analysis (CS 537)• Preparing Future Faculty (GS 650)

Total credit hours: 21

Objectives

To provide the mining industry an effective CFD simulation package for analysis and design of face ventilation systems during deep cut mining.

Research Performed

• CFD code validation using data obtained from previously conducted experiments on small scale and full size physical models.

• CFD code optimization for best performance

• Preliminary CFD simulations of face ventilation scenarios for blowing and exhausting line-brattice.

Results of the conducted research study

Validation of SC/Tetra CFD code using PIV measurements of 1:15 scaled physical model

B. Simulated results

Experimental SetupEquipment free face area; Tide-rib distance 2 ft; Setback 35 ft; Height 7 ft; Flow rate 2700 cfm

3,6 m 4,3 m 4,9 m 6.1 m

(12 ft) (14 ft) (16 ft) (20 ft)

3,6 m 4,3 m 4,9 m 6.1 m

(12 ft) (14 ft) (16 ft) (20 ft)

A. PIV Data (Wala et. al. 2000-2004)

Results of SC/Tetra CFD simulations for free of equipment face area

(a) Curtain distance from the rib of 0.3 m (1 ft)

(b) Curtain distance from the rib of 0.6 m (2 ft)

(c) Curtain distance from the rib of 1.2 m (4 ft)

Results of the simulation study for flow rate• 1.3 m3/s (2700 cfm)

The results for • 1.7 m3/s (3500 cfm), • and 2.6 m3/s (5500 cfm) are similar

3,6 4,3 m 4,9 m 6.1 m

(12‘ (14') (16') (20’)

3,6 4,3 m 4,9 m 6.1 m

(12‘ (14') (16') (20’)

3,6 4,3 m 4,9 m 6.1 m

(12‘ (14') (16') (20’)

Line brattice distanced', (ft)

Entry width, w (ft)

12 13 14 15 16 20

1 A* A A* A A A

2 B* B B* C* A* A*

3 B B B B B B

4 B* B* B* B B B*

Stages of the flow behavior

A A A A

A AB B

B B B B

The asterisks mark the validated scenarios

Validation of Cradle SC/Tetra CFD code using airflow and methane measurements collected during experiments

conducted in NIOSH Research Gallery for equipment free face area

• Simulation results

Experimental setup

• 30 feet deep Box cut (35 ft setback distance)

• 6000 cfm air flow rate• 5.27 cfm methane flow rate

The results of this experimental studies were presented during 2005 SME Annual Meeting at Salt Lake City (Taylor et. al., 2005).

• Experimental results

X

Y

0 10 20 300

10

20

30

Ch4

0.60.50.40.30.20.10

Measured and simulated methane distribution

• Experimental data v/s simulation results for the mid-plane• Correlation coefficient = 0.72

0 5 10 15 20 25 30 35 400.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

3.5’

Measurement point number

CH4

Section in X-Z plane

X-Y Plan view above the miner

Section in X-Y middle plane

X-Y Plan view below the miner

The results of the experimental study were presented during 12th U.S./North American Mine ventilation Symposium (Wala et. al. 2008)

Simulated scenario:• Box cut• Box cut width 13 ft• Total entry width 16.5 ft• Tide rib distance 2 ft• Air flow 4000 cfm• Scrubber flow 4000 cfm• Methane flow 13.4 cfm

Validation of SC\Tetra CFD code using airflow and methane measurements collected during benchmark experiments conducted in NIOSH Research Gallery

with a continuous miner equipped with a scrubber

Measured and simulated methane distribution

• Correlation coefficient = 0.65

0 5 10 15 20 25 30 35 400.00

0.10

0.20

0.30

0.40

0.50

0.60

Measurement point number

CH4

Parallel position

Simulated methane concentration for different position of the miner

Miner turnedleft on 1.5 deg

Miner turnedRight on 1.5 deg

• Same scenario as previews for 3 different positions of the miner

Parallel position

Simulated methane Concentration

• 3D view with isosurface of methane concentration = 1%

Miner turnedleft on 1.5 deg Miner turned

Right on 1.5 deg

CFD simulation of face ventilation applying original geometry of JOY14CM15 continuous miner

Geometry provided by Joy Mining Machinery Inc

Blowing line brattice

Scrubber effect on methane concentration.

Simulated scenario:

• Blowing line brattice• Box cut• Box cut width 13 ft• Total entry width 16.5 ft• Tide rib distance 2 ft• Air flow 6000 cfm• Scrubber 4000 cfm• Methane flow 13.4 cfm

Blowing line bratticeMethane concentrations above the miner

(plane z=5.6 ft)

Scrubber off Scrubber 4000 cfm Scrubber 5000 cfm

Blowing line brattice

• Methane concentration profiles

Exhausting line brattice

Scrubber OFF

Isosurface of methane concentration of 5%

Exhausting line bratticeScrubber ON

4000 cfm

Isosurface of methane concentration 1%

Exhausting line bratticeMethane concentrations above the miner

(plane z=5.6 ft)

Scrubber off Scrubber 4000 cfm

Simulated scenario:

• Exhausting line brattice• Box cut• Box cut width 13 ft• Total entry width 16.5 ft• Tide rib distance 2 ft• Air flow 6000 cfm• Scrubber 4000 cfm• Methane flow 13.4 cfm

Future work

• Design and development of CFD models database for different face ventilation systems.

• Design and development of specialized software engine for automation of Face Ventilation Simulation process based on Microsoft VB interface supported by Cradle to handle SC/Tetra built-in functions as methods and variables.

• Testing and validation study of the developed design package

Concept for automation of Face Ventilation Simulation process Todor Petrov, University of Kentucky

FVSdatabase

SCT prime

Specify model

Specify conditions

CADfiles

CADfiles

Modelfile

Conditionsfile

Modelfiles

Modelfiles

Conditionfiles

Conditionfiles

SCT pre

SCT solver SCT preSCT post

START

Face Vent. Sym.