Low noise fans engineered to meet your specific sound requirements

Multi-Wing America specializes in custom engineered low noise fans for a spectrum of engine cooling, radiator, HVAC and refrigeration applications. The need for low noise fans has become vital for any hearing conservation program in accordance with the Occupational Safety & Health Administration’s (OSHA) Noise and Hearing Conservation Standards for workplace noise. Overseas, the European Parliament and Council adopted Directive 2000/14/EC on environmental noise on May 8, 2000, setting stringent guidelines for sound-power limits on 22 of the 57 types of equipment used outdoors. These legislative measures outline provisions for noise mapping, protection against the effects of noise exposure, action plans for reduction, and set new noise emission standards for industries in America and around the world. Compliance is mandatory, and Multi-Wing is an unsurpassed resource for low noise fans.

Although the current international focus on sound reduction programs can be intimidating, Multi-Wing America’s low noise fans have significantly cut decibel levels in a variety of industrial applications. Our low noise sickle and airfoil profiles are a vital component in sound reduction because their twisted design reduces turbulence across the blade’s surface, and the blades’ thin trailing edge reduces the vortex created as air leaves the surface. Blade design is vital in engineering a low noise fan, but it doesn’t stop there. Air turbulence causes fan noise, so Multi-Wing engineers also recommend examining several other variables to reduce decibel levels.

First, ensure an aerodynamic cooling system by minimizing the number of upstream obstructions and creating as much distance as possible between any obstructions and the fan. Second, create the most efficient possible inlet geometry to reduce turbulence and improve the fan’s operating efficiency, because operating at peak efficiency is vital for low noise fans. Third, keep a tight tip clearance to reduce vortex shedding – air leaving the blade – at the tips, which also reduces low wake turbulence and decibel levels. And finally, decrease the fan speed whenever possible, because higher rotational speeds generally create greater noise. Larger fans can run at slower speeds and generate the same airflow while reducing the pure tonal noise caused by blade pass frequency. Focusing on these variables and using blade profiles designed for sound reduction is key in engineering optimized low noise fans.