Tunnel Jet Fans
Longitudinal tunnel-ventilation fans engineered around required jet thrust, air velocity, tunnel geometry and operating strategy. RAFAVENT tunnel jet-fan construction is available from Ø560 to a maximum family size of Ø1400.
Selection basis
Primary duty
Required installed thrust in newtons, traffic direction, tunnel cross-section, spacing and permissible air velocity.
Installation losses
Ceiling clearance, wall proximity, silencers, mounting cradle, obstructions and cross-flow can reduce effective installed thrust.
Operating mode
Unidirectional or reversible airflow, normal ventilation, emergency strategy, VFD control and redundancy philosophy.
Preliminary model selection
Nominal thrust is calculated from air momentum at standard-density air (approximately 1.2 kg/m³). Use installed-thrust correction factors during detailed design.
| Model | Impeller | Nominal airflow (m³/h) | Outlet velocity (m/s) | Nominal thrust (N) | Preliminary motor selection (kW) | Speed (rpm) | Preliminary estimated LpA at 3 m dB(A) |
|---|---|---|---|---|---|---|---|
| TJF-560 | Ø560 | 20,000 | 22.6 | 151 | 5.5 | 1450 | 78 |
| TJF-630 | Ø630 | 28,000 | 24.9 | 232 | 7.5 | 1450 | 80 |
| TJF-710 | Ø710 | 40,000 | 28.0 | 373 | 11 | 1450 | 83 |
| TJF-800 | Ø800 | 55,000 | 30.4 | 557 | 18.5 | 1450 | 86 |
| TJF-900 | Ø900 | 72,000 | 31.4 | 754 | 22 | 980 | 88 |
| TJF-1000 | Ø1000 | 90,000 | 31.8 | 954 | 30 | 980 | 90 |
| TJF-1120 | Ø1120 | 110,000 | 31.0 | 1,137 | 37 | 980 | 92 |
| TJF-1250 | Ø1250 | 135,000 | 30.6 | 1,377 | 55 | 980 | 94 |
| TJF-1400 | Ø1400 | 160,000 | 28.9 | 1,540 | 75–110 | 740–1200 | 95 |
Calculated performance curves
Six-point speed-law presentation at 0%, 25%, 50%, 75%, 90% and 100%: airflow varies approximately with speed, thrust with speed² and absorbed power with speed³. Displayed thrust is rounded to the nearest newton and power to 0.1 kW. Values are preliminary and exclude installation corrections.
TJF-560 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 5,000 | 9 | 0.1 |
| 50% | 10,000 | 38 | 0.7 |
| 75% | 15,000 | 85 | 2.3 |
| 90% | 18,000 | 122 | 4.0 |
| 100% | 20,000 | 151 | 5.5 |
TJF-630 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 7,000 | 15 | 0.1 |
| 50% | 14,000 | 58 | 0.9 |
| 75% | 21,000 | 131 | 3.2 |
| 90% | 25,200 | 188 | 5.5 |
| 100% | 28,000 | 232 | 7.5 |
TJF-710 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 10,000 | 23 | 0.2 |
| 50% | 20,000 | 93 | 1.4 |
| 75% | 30,000 | 210 | 4.6 |
| 90% | 36,000 | 302 | 8.0 |
| 100% | 40,000 | 373 | 11.0 |
TJF-800 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 13,750 | 35 | 0.3 |
| 50% | 27,500 | 139 | 2.3 |
| 75% | 41,250 | 313 | 7.8 |
| 90% | 49,500 | 451 | 13.5 |
| 100% | 55,000 | 557 | 18.5 |
TJF-900 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 18,000 | 47 | 0.3 |
| 50% | 36,000 | 189 | 2.8 |
| 75% | 54,000 | 424 | 9.3 |
| 90% | 64,800 | 611 | 16.0 |
| 100% | 72,000 | 754 | 22.0 |
TJF-1000 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 22,500 | 60 | 0.5 |
| 50% | 45,000 | 239 | 3.8 |
| 75% | 67,500 | 537 | 12.7 |
| 90% | 81,000 | 773 | 21.9 |
| 100% | 90,000 | 954 | 30.0 |
TJF-1120 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 27,500 | 71 | 0.6 |
| 50% | 55,000 | 284 | 4.6 |
| 75% | 82,500 | 640 | 15.6 |
| 90% | 99,000 | 921 | 27.0 |
| 100% | 110,000 | 1,137 | 37.0 |
TJF-1250 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 33,750 | 86 | 0.9 |
| 50% | 67,500 | 344 | 6.9 |
| 75% | 101,250 | 775 | 23.2 |
| 90% | 121,500 | 1,115 | 40.1 |
| 100% | 135,000 | 1,377 | 55.0 |
TJF-1400 — calculated speed/thrust curve
| Speed setting | Airflow (m³/h) | Nominal thrust (N) | Absorbed power estimate (kW) |
|---|---|---|---|
| 0% | 0 | 0 | 0.0 |
| 25% | 40,000 | 96 | 1.2 |
| 50% | 80,000 | 385 | 9.4 |
| 75% | 120,000 | 866 | 31.6 |
| 90% | 144,000 | 1,247 | 54.7 |
| 100% | 160,000 | 1,540 | 75.0 |
Ø1400 project-engineered reference duty
RAFAVENT has developed a pressure-loaded Ø1400 tunnel axial arrangement with inlet/outlet silencers and downstream guide vanes. This reference is distinct from the generic free-jet thrust ratings above.
| Impeller | Speed | Calculated reference motor | Airflow | Static pressure | Arrangement | Data status |
|---|---|---|---|---|---|---|
| Ø1400 mm | 1200 rpm | 110 kW | ≈116,000 m³/h | ≈1270 Pa | Silencers both sides, downstream guide vanes, VFD-ready | Calculated project design; non-certified |
Construction and installation options
- Rolled, flanged heavy-gauge steel casing
- Project-specific corrosion-protection coating
- Aerodynamic impeller with adjustable design pitch
- External terminal box and protected cable routing
- Inlet and outlet attenuators sized to the duty
- Mounting cradle, feet or ceiling suspension arrangement
- Anti-vibration mounts and flexible connections where required
- Protective guards and inspection access
- Reversible impeller/motor arrangement where specified
- VFD suitability subject to motor and cable selection
Installed-thrust engineering checks
Geometry
Confirm tunnel area, hydraulic diameter, fan spacing, mounting elevation and clearance from soffit and walls.
Aerodynamics
Apply corrections for silencers, inlet distortion, cross-wind, traffic blockage and interaction between adjacent fans.
Electrical & controls
Confirm start method, VFD range, emergency sequence, motor protection, IP class and project power supply.
Information required for final selection
Provide required installed thrust, tunnel dimensions, ambient and emergency temperatures, reversible duty, permissible sound level, available electrical supply, control philosophy, mounting limits, coating environment and applicable project certification requirements.
Technical documents, dimensions and service
Technical documents and dimensions
Final dimensions, mounting details, silencer arrangement, materials, motor data and project drawings are issued for the selected tunnel and duty after engineering review.
Installation and maintenance
Confirm structural supports, installation clearances, access, cable routing, guards, vibration control and the approved project-specific O&M requirements.
Selection tables and calculated thrust curves are preliminary engineering guidance, not certified RAFAVENT test ratings or F300/F400 evidence. Confirm the installed thrust, operating duty and controlled documents before order.
Request an engineering selection
Send the duty point, installation arrangement, operating conditions and available drawings for a project-specific selection.
Send project requirements