Tunnel Ventilation / Construction & Operation
Tunnel Ventilation Fans
Tunnel ventilation fan solutions for two different project stages: SDF duct-connected fans for construction-stage fresh-air supply and SDS jet fans for longitudinal ventilation in completed road tunnels.
The first selection decision is the project stage. Construction ventilation and completed-tunnel operation use different airflow methods, different installation arrangements and different fan-selection parameters.
Construction Stage
SDF Tunnel Fan
Ducted fresh-air supply
Operation Stage
SDS Jet Fan
Longitudinal ventilation
Selection Logic
Stage First
Then airflow / pressure / thrust
Engineering Review
Tunnel + Ventilation Route
Project data before model selection
01 · Project Overview
Tunnel Ventilation Starts with the Project Stage
Tunnel ventilation fan selection should begin with one question: is the tunnel still under construction, or is it already in normal operation?
During construction, ventilation normally relies on duct-based fresh-air supply to deliver air to the advancing tunnel face. After completion, road-tunnel ventilation commonly uses jet fans to generate longitudinal airflow for vehicle exhaust control and smoke-control support.
QIYUE FAN therefore uses two main product directions on this page: SDF tunnel ventilation fans for construction-stage duct air supply and SDS tunnel jet fans for completed road-tunnel operation.
Selection boundary: SDF and SDS serve different project stages. Confirm the ventilation method first, then review airflow, pressure, thrust, fan diameter, motor power and detailed model selection.
For complete construction-stage system engineering, including duct resistance, maximum ventilation distance and working-face airflow, see Tunnel Construction Ventilation System →
02 · Project Stage Comparison
Construction Duct Ventilation vs Road Tunnel Jet Ventilation
SDF and SDS tunnel fans serve different project stages. The core difference is the ventilation method, installation position and selection parameter.
ITEM
CONSTRUCTION STAGE
OPERATION STAGE
Ventilation Method
Forced fresh-air supply through flexible or rigid ventilation ducting
Longitudinal airflow generated by tunnel jet fans
Main Purpose
Fresh-air delivery, tunnel-face ventilation and dilution of construction dust, blasting fumes and equipment exhaust
Traffic ventilation, vehicle-exhaust control and smoke-control support
Selection Focus
Tunnel length, duct diameter, maximum duct length, working-face airflow and system pressure loss
Required thrust, tunnel section, fan spacing, mounting clearance, noise and smoke-control strategy
Installation Method
Connected to the ventilation duct and installed according to the construction ventilation route
Usually suspended from the tunnel ceiling or installed in the upper side area according to the tunnel design
Primary Performance Parameter
Airflow + pressure
Jet thrust + tunnel airflow effect
Routing rule: construction-stage duct ventilation → review SDF first. Completed road-tunnel longitudinal ventilation → review SDS first.
03 · Main Fan Directions
Two Fan Directions for Tunnel Ventilation
These two product families should not be compared as direct substitutes. Their project stage and aerodynamic duty are different.
Construction Stage
SDF Tunnel Ventilation Fan
SDF tunnel ventilation fans are used for long-distance duct air supply, tunnel-face ventilation, construction dust dilution and underground working-area airflow support.
Selection focus: required working-face airflow, duct length, duct diameter, system pressure loss, leakage, installation position and maximum ventilation distance.
Operation Stage
SDS Tunnel Jet Fan
SDS tunnel jet fans are used for completed road-tunnel longitudinal ventilation, vehicle-exhaust control and smoke-control support during normal operation or emergency conditions.
Selection focus: required thrust, tunnel cross-section, fan spacing, mounting clearance, operating strategy, noise and smoke-control requirements.
Do not select by appearance: SDF and SDS are both axial-type fan directions, but their aerodynamic duty, installation method and project role are different.
04 · Tunnel Fan Selection
Confirm the Ventilation Route Before Selecting the Fan
Tunnel fan selection should first confirm the project stage, then review the airflow method, tunnel dimensions, duct or jet-ventilation arrangement and operating conditions.
01
Project Stage
Confirm whether the tunnel is under construction or already completed for road-tunnel operation.
02
Airflow Method
Construction projects normally use duct air supply. Completed road tunnels normally use longitudinal jet ventilation.
03
Tunnel Length
Tunnel length affects construction-stage duct resistance and completed-tunnel jet-fan spacing.
04
Airflow or Thrust
SDF selection focuses on airflow and pressure. SDS selection focuses on jet thrust and tunnel airflow control.
05
Dust and Smoke
Construction dust, blasting fumes, vehicle exhaust and emergency smoke-control duty should be reviewed separately.
06
Installation Method
SDF connects with the ventilation duct. SDS is normally suspended from the tunnel ceiling or installed in the upper side area.
Construction-stage SDF: review maximum tunnel length, duct diameter, maximum duct length, airflow, system pressure loss and leakage.
Operation-stage SDS: review required thrust, fan spacing, mounting location, tunnel section, normal ventilation and smoke-control requirements.
Operation-stage SDS: review required thrust, fan spacing, mounting location, tunnel section, normal ventilation and smoke-control requirements.
05 · Typical Applications
Tunnel and Underground Ventilation Projects
Construction
Road Tunnel Construction
Duct-based fresh-air supply for road-tunnel excavation, working-face ventilation and construction-dust dilution.
Construction
Railway Tunnel Construction
Long-distance duct ventilation for railway tunnel excavation and underground working zones.
Construction
Mine Tunnel Excavation
Fresh-air support for mine tunnel excavation, underground roadway construction and local working areas.
Operation
Completed Road Tunnel
Jet-fan ventilation for completed highway tunnels, mountain tunnels and urban road tunnels.
Operation
Smoke-Control Support
Longitudinal airflow and emergency smoke-control support according to the completed tunnel ventilation design.
Existing Tunnel
Tunnel Renovation
Fan review for airflow upgrades, replacement, ventilation improvement and smoke-control retrofit projects.
06 · Related Tunnel Ventilation Resources
Continue from Project Stage to System Design and Fan Selection
Buyer FAQ
Tunnel Ventilation Fan Questions
01
What Is the Difference Between SDF and SDS Tunnel Fans?
SDF tunnel fans are used during construction with ventilation ducting for forced fresh-air supply. SDS tunnel jet fans are used in completed road tunnels for longitudinal ventilation and smoke-control support.
02
When Should a Tunnel Duct Ventilation Fan Be Selected?
A tunnel duct ventilation fan should be reviewed when the tunnel is under construction and fresh air must be delivered through ducting to the tunnel face or underground working area.
03
When Should a Tunnel Jet Fan Be Selected?
A tunnel jet fan is reviewed for completed road tunnels requiring longitudinal airflow, vehicle-exhaust control and smoke-control support during operation.
04
What Information Is Needed for SDF Tunnel Fan Selection?
Provide the tunnel length, tunnel section, required working-face airflow, duct diameter, current and maximum duct length, pressure or resistance data, power supply and installation position.
05
What Information Is Needed for SDS Jet Fan Selection?
Provide the tunnel section, tunnel length, required thrust or project fan schedule, installation spacing, mounting clearance, power supply, noise requirement and smoke-control duty.
06
Can QIYUE FAN Review a Tunnel Fan from Project Data?
Yes. Send the project stage, tunnel dimensions, ventilation route, airflow or thrust requirement, duct or mounting conditions, power supply, installation method and quantity for preliminary fan-direction review before quotation.
Routing Rule
Construction = SDF
Operation = SDS
Stage first.
Construction = SDF
Operation = SDS
Stage first.
Tunnel Ventilation Fan Selection
Send the Tunnel Stage and Ventilation Requirements
Project Stage · Tunnel Length · Tunnel Section · Duct Diameter · Duct Length · Airflow · Pressure or Thrust · Power Supply · Installation Method · Smoke / Dust Conditions
01
Project Stage
02
Tunnel Size
03
Duct / Spacing
04
Airflow / Thrust
05
Voltage / Quantity
Project Contact
Manager Zhao
Tunnel Ventilation Fan Selection