BNC Counter Flow Closed Circuit Cooling Tower ( Centrifugal fans）

BNC Counterflow Closed-Circuit Cooling Tower (Centrifugal Fans)

Product Overview

The BNC Counterflow Closed-Circuit Cooling Tower with centrifugal fans is specifically designed for installations where external air discharge is not possible or noise must be strictly controlled. Unlike axial fans, centrifugal fans can overcome higher static pressures, making the BNC ideal for indoor or ducted installations. This tower ensures efficient cooling performance while maintaining very low noise levels, even in enclosed spaces.

Working Principle

The process fluid circulates inside a closed coil, while spray water is pumped from the basin and distributed evenly across the coil surface. Centrifugal fans draw air from the surroundings and force it upward through the coil in a counterflow arrangement. The design allows for duct connections, so conditioned air can be guided directly to the tower. Heat is rejected via evaporative cooling, and the cooled water is collected and recirculated in the basin. The closed-loop design prevents contamination of the process fluid.

Applications

• Indoor Machine Rooms: Particularly suited for high-rise buildings and basements.
• Hospitals and Laboratories: Locations requiring ultra-low noise and clean operation.
• Data Centers: Reliable cooling with noise control and ducted air discharge.
• Urban Environments: Projects where external fan noise is unacceptable due to residential proximity.

Performance & Efficiency

The centrifugal fan system provides stable airflow regardless of duct pressure, allowing the tower to be placed in enclosed areas. Although centrifugal fans consume more energy compared to axial fans, the efficiency of the heat rejection system ensures reliable performance. Optional VFDs (variable frequency drives) help optimize fan speed, reducing unnecessary energy consumption while maintaining cooling capacity.

Key Advantages

• Low-noise centrifugal fans suitable for noise-sensitive applications.
• Compatible with duct systems for indoor installation.
• Closed-loop design eliminates contamination risk.
• Reliable cooling performance with stable airflow control.
• Optional silencers and vibration isolators further reduce sound levels.

Selection Guide

When selecting the BNC model, engineers must evaluate duct pressure losses, static pressure requirements, and noise restrictions. It is particularly recommended for basements or machine rooms with duct connections. For environments with high hygiene requirements, stainless steel coil construction is advisable. Where space is tight, modular configurations allow flexibility during installation.

Development Trend

Future centrifugal fan cooling towers are being designed with higher efficiency fan blades, advanced acoustic materials, and digital monitoring systems. Integration with smart building systems allows predictive maintenance and optimized fan control. The trend is toward quieter, more compact units that can be seamlessly installed in indoor environments.