THis presentation deals with Tunnel Ventilation concepts, with special reference to T80, India's longest transportation tunnel across Pir Panjal range, connecting Jammu region to Kashmir valley

1. TUNNEL VENTILATION AND
FIRE SAFETY
A case study of
Pirpanjal Tunnel T80
0f USBRL Project
-Hitesh Khanna & Sandesh Srivastva
Ircon International Limited

2. PIR PANJAL TUNNEL- AN OVERVIEW
• IRCON INTERNATIONAL LIMITED is the principle
execution agency for DHARAM-QAZIGUND-
BARAMULLAH section of USBRL project of
Northern Railway.
• Pir Panjal Tunnel, between Qazigund and
Banihal, is the landmark tunnel of the
project, connecting Kashmir Valley to Jammu
Region.
• At 11.215 Kms., it is the LONGEST transportation
tunnel in India.
2

3. T 80 ON USBRL PROJECT
3

4. T80 SECTION AND PLAN
4

5. • Max Over burden 1100
mts.
• B. G. Rly. S/L Track
• 3 mts. Road
• 48.5 m2 X-Sec Area
• Water Proof
5

6. Ventilation Requirement
• Normal Operation (Depends on Traction Mode):
– Maintain Sustainable Air Quality in side the Tunnel
• Pollutant Levels
• Oxygen Levels
• Temperature
• Emergency Rescue Management (Depends on
Fire Load):
– Fire and Smoke Management to Assist Emergency
Evacuation Strategy
– Fire Effect Mitigation
6

7. • Detailed Design
Consultants
– M/s Geoconsult-
RITES JV
– Overall Tunnel Design
and Top level
Supervision, observat
ions based On-site
design with NATM
approach
– Ventilation, Rescue, E
&M Design
7

8. • HBI Haerter
– Ventilation
Design
Proof
Check
8

9. STANDARD THRESHOLD POLLUTION LEVEL
(1) (2) (3)
CO 50 75 400
NO 25 37.5 35
NO2 5 5 5
American Conference of Governmental and Industrial Hygienists
and Continuous Limit for working environment. (Ref. DPR)
1) Long Term Sustainable Threshold Values for Industrial Working
Environment (8 hours working)
2) Non-Continuous Exposure, with intermittent Air Exchange
3) Limits up-to 15 minutes exposure
9

10. ADOPTED THRESHOLD ENVIRONMENT
PARAMETERS
Design
8 Hours
Element 15 Min. Exposure Limit
Exposure
Pir Panjal
CO 50 ppm 200 ppm 50 ppm
NO 25 ppm 35 ppm 90% of NOx
NO2 4 ppm 5 ppm 10% of NOx
Sum: NOx 29 ppm 40 ppm 25 ppm
CO2 5000 ppm 10000 ppm 5000ppm
SO2 5 ppm 5 ppm 5ppm
< 0,012m^-1
Particulates
Not defined Not defined (extinction
(PM)
coefficient)
Temperature 40°C 50°C for a train passing, max.65°C - 10

11. LOCO MOTIVE EXHAUST DATA
emission Standards measured emission data
US EPA
(line haul
locomotive, WDM2/ALCO WDM3A/AL WDM4/ALCO
g/kWh ORE UN UIC Tier 0) 2530HP CO 3073HP 4000HP
CO 3 6.7 3 6.71 0.52 0.72 0.56
NOX 12 12.7 10 10.73 13.56 12.42 7.62
Particle 0.5 0.8 0.25 0.30 ??? ??? 0.39
11

12. Ventilation For Fire and Smoke
Management
What happens if a tunnel fire occurs ?
the tunnel roof fills with smoke
even in the upstream direction against the
longitudinal velocity!!
12

13. Ventilation For Fire and Smoke
Management
• Smoke To Be
Directed, to
Permit Escape in
other direction
• Avoid
BACKLAYERING
" Backlayring
– Critical Velocity
of Airflow to be
Maintained
13

14. Stratification Of Smoke
• Smoke Rises to Top
– Permits Escape
Underneath in cooler
air
– Flashover Control
• Typically Stratification
lasts for 500-800mts
– 30-40 MW fire
– Tunnel Geomtry, Slope
– Air Flow Conditions
14

15. VENTILATION DESIGN INPUTS SMOKE
CONTROL
• Input Parameters
– What is the maximum size of any fire, which may
reasonably be expected to occur, given the use of
tunnel
• (Design Fire Curve- Fire/Smoke Vs. Time)
– What Corresponding Ventilation is required to
prevent smoke Backflow
• Critical Velocity to be attained
15

16. VENTILATION SYSTEMS
• Longitudinal
– Air Set in Motion along Tunnel Axis
• Portal to Portal, Same speed though out the Tunnel Length
• No Division into Aerodynamic Segments
• Low Cost, Does not need Transverse air Egress Points
• Time to Purge Foul Air depends on Air Flow Velocity, Tunnel
Length 16

17. VENTILATION SYSTEMS (contd.)
• Transverse
– Two Independent Ducts (Fresh Air Inflow and Exhaust
air exit)
• Can create Aero dynamic Sections (In case of Fire)
• May Need Transverse Exit Routes (Low Overburden
Ventilation Shafts, Stations in Metros
• Costlier to Install, and operate (More Aerodynamic Losses)
17

18. VENTILATION SYSTEMS (contd.)
• Semi-Transverse
– Combination of Longitudinal and Transversal System:
• Separation of Fresh and Exhaust air
• Reversible-
• Fire Case Fresh Air through Portal, Exhaust through
Ventilation Stack, Permitting Aerodynamic Separation
• Normally, Fresh air Through Ventilation Stacks
• Larger Tunnel X-Section 18

19. VENTILATION SYSTEMS (contd.)
• Considering the merits and demerits of each
ventilation system and since there is no
station and stop in pir-panjal tunnel;
longitudinal ventilation system has been
considered fit to apply in this tunnel &
worldwide also, only longitudinal ventilation
is applied to rail/road tunnel or underground
projects. Only in underground stations and
stops, transversal and semi transversal might
be applied.
19

20. Boundary Conditions (Geometric Data)
20

21. Boundary Condns. (Geometry)
Description Details
Tunnel length 11.215 m
Length from Banihal Station to South 1450 m
portal
Length from North Portal to 4774 m
Qazigund Section
Finished cross section 48.50 m2
Average elevation above sea level 1734.75 m 21

22. Thermo Dynamic Data
ITEM REFERENCE
Geothermal Heat Input Para 3.2.2
Depending on Parent Rock
Temperature and Temp. Gradient
to Tunnel Rock Surface
Temperature, Pressure and Density Para 3.2.2.1
Gradient of Air Inside the Tunnel
Portal Meteorological Data Para 3.2.3
Portal Temperature, Wind Pressure, Para 3.2.3.1, 3.2.3.2, 3.2.3.3, 3.2.3.4
Natural Buoyancy Pressure and Pressure
Differential between the Portals
22

23. Aero Dynamic Data
ITEM REFERENCE
Tunnel Characteristics: Para 3.4
Portal Losses, Tunnel Wall Friction,
Wind Velocity at Portals
Air Pressure and Temperature
Air Density
Critical Velocity Critical Velocity to prevent Back Layering
Critical Froude Number Constant Air flow to Blow the Smoke
Temperature Near The Fire Scene away from Passengers Exiting in Other
Direction,
Drive HC Vapours Away from Fire Source
to avoid Flash Over
Jet Fan Installation Factor & Para 3.5 & 3.6
Piston Effect Of The Train and
Train Data 23

24. THERMODYNAMICS
...buoyancy…
a thermodynamic effect
warm mass of rock
temperature rise leads to lower density of air
heat of train
…. and to longitudinal velocity - chimney effect
24

25. ...wind pressure and
meteorological effects...
wind pressure effect depends on:
Tunnel
- meteorological situation
- tunnel data wind pressure
25

26. AERODYNAMICS
...piston effect …
depends on:
for the Pir Panjal tunnel
the piston effect leads to:
Tunnel
- speed of train and aerodynamic drag
• longitudinal velocity of about 5.34 m/s
• fresh air of about 241 m3/s
- ratio between tunnel and train cross section area
- tunnel resistance: length of tunnel, wall friction and others
26

27. Calculation Of Fresh Air Flow
• Para 3.6.2
– Fresh Air Demand due to Gaseous Emissions
– Fresh Air Demand due to Particulate Emissions
– Fresh Air Demand oxygen Depletion (Diesel Engine)
– Normalization Of Temperature (Below 40 deg. C)
after passage of 5000T train Uphill
• Ventilation Design (Normal Case) Para 4.0
– Time to restore Safe Conditions Inside the Tunnel
– Waiting Time for Next Train to enter (after exit of
Uphill Loaded Train)
27

28. TRAIN SIMULATION TO ASSESS
VENTILATION NEED
longitudinal velocity
longitudinal velocity
5,00
4,00
3,00
2,00
1,00
[m/s]
0,00
0 60 120 180 240 300
-1,00
-2,00
-3,00
-4,00
-5,00
time [min]
For normal operatrion
No artificial ventilation is needed
Train with 40 km/h needs about 17 min to pass tunnel
28

29. Ventilation Design Approach
Natural velocity achieved inside tunnel :
29

30. Emergency Ventilation Design Fire
• Select Design Fire Load:
Investigations were
performed by Deutsche
Bahn AG
– Diesel Loco → Peak 20
MW
– Electric Loco → Peak 12
MW
– Passenger train → Peak
25 MW
– Freight train → Peak 8-
52 MW (depending on
load)
• Design Fire Adopted 40
MW (Two Dsl. Loco in
Tandem)
30

31. Emergency Ventilation Design Approach:
TEMPERATURE /
SMOKE PROGRESSION
ALONG THE LENGTH
HEIGHT
Computation fluid
dynamics (camatt)
– Design Fire
– Tunnel Geometry
– Fan design &
Configuration
– Thermo Dynamics
– Fluid Dynamics
31

32. Emergency Ventilation Design Approach:
TEMPERATURE / SMOKE
PROGRESSION ALONG THE
LENGTH HEIGHT BY NEAR FIRE
CONDITIONS BY 3DCFD
Objective:-
– To clarify condition d/s of
fire
– Influence of longitudinal
flow velocity on the
tenability d/s from fire
– Design Fire load 25 MW
– Smoke plum should remain
2.5m above rail level during
self evacuation time
– Use of Deutsche Bahn Fire
curve for smoke release rate
and critical velocity
32

33. Ventilation Requirement with Electric
Traction
No ventilation required for regular operation
Fire load for electric locomotives < Diesel powered ones
According to design procedure and UIC
→ fire load depends on type of train
→ typical criteria *:
* According to Deutsche Bahn AG
● Diesel → Peak 20 MW
● Electric → Peak 12 MW
● Passenger train → Peak 25 MW
● Freight train → Peak 8-52 MW (depending on load)
Chosen design criteria → 40 MW
Electric traction does not impact ventilation design Page 33

34. FINAL VENTILATION DESIGN
Jet Fan (Main Tunnel)
Jet Fan (Access Tunnel)
34

35. Proposed E&M System Outline
World
Standard
Pir Panjal UIC Comments
Redundant Power Supply   ~ I-67, I-65
I-68
CCTV System   
Emergency and Service Phone System    I-42
I-66, I-2
Tunnel Radio System   
Public Address System (Speaker
System)   ~
Fire Detection System   
Fire Fighting System (Water I-24, I-64
Line, Extinguishers)
  
Ventilation System    I-25
Emergency Lighting    I-41
Control Centre   ~
Page 35

36. FUNCTIONAL X-SECTION OF T80
36

37. E&M System
Consists of the following
433/250V – 50 Hz Power Supply
Emergency Power Supply
Earthing & Potential Equalisation
System
Tunnel Lighting
Tunnel Fittings
Fire Detection System
Building Power & Lighting Installations
Room Ventilation & Air Conditioning
37

38. Ventilation Control Eqpmnts
 Visibility detection
 Airflow measurement
 Automatic operation
 Basic ventilation
Visibility data
Airflow direction
Wind speed
 Fire Ventilation
Fire Alarm
Visibility data
Airflow direction
Wind Speed 38

39. VENTILATION CONTROL STRATEGY
REQUIREMENTS TO THE STAFF (NORMAL
OPERATION)
Train staff
►Report about type and direction of train
entering the tunnel
►Break down: Report the location of the break
down
Control center staff
►Know about train type and direction
►Monitor emission levels in the tunnel
►Monitor appropriate operation of ventilation
►Instruct the train driver to shut down engines (if
necessary) 39

40. Ventilation Control Strategy
Requirements to the staff (emergency operation)
Train staff
►Guide passengers in the right direction
►Communicate and Local Guidance for Passenger
Rescue
Control center staff
►Select and confirm the appropriate mode of
operation
►Monitor the appropriate mode of ventilation
►Support rescue operation (e.g. coordinate the
rescue train)
40

41. 41