High Pressure Centrifugal Fans or High Pressure Centrifugal Blowers are fluid and move particles that expel the flow from it at a 90 degree angle to the intake axis during operation. They are sometimes interchangeably called fans or blowers but are known more as the latter. What is the difference between a fan and a blower? A fan is an air movement device used for ventilation, fluid movement, heat and cool air delivery or drying. Blowers are mostly particle movement devices which use compressed air to blow or overcome strong resistances in flow, or to displace solids. Basically, fans generate air movement, while blowers generate air movement and high pressures.
High Pressure Centrifugal Design
Regular to moderate pressure Centrifugals consist of an open impeller with specifically designed ribs or blades. The ribs can be seen at the inlet of the impeller which is located at the eye of the wheel. The housings are fairly thick and the impellers are fat in size. These centrifugals create good pressures during operation and are sometimes constructed out of sheet metal and not so strong housings. They are relatively open and the moving parts can be easily seen. Some very efficient and sturdy designs consist of backward inclined blades to keep particles from building up on the inside and directly on the impeller’s contact area. Particle build up can cause unwanted turbulences and hence contribute to lowered efficiency and function.
High pressure Centrifugals are very thin and the impeller is closed off except at the eye and the circumference. These centrifugals are very efficient and are built for extremely high static pressures. They are constructed from stainless steel and strong alloys. Good designs of High Pressure Centrifugals are split in the middle and allow the housing to be de-assembled to access the impeller for cleaning without messing with connections to the inlet or outlet such as ducting or dampers. High Pressure Centrifugals are good for up to 20,000 pascals. Due to the high heat generated by operation, the shaft can be cooled to ensure longevity and continuation of operation. These centrifugals tend to be very noisy, so a silencer can be fitted to assist with acoustic treatment and lower operating decibels. The exposure to corrosive gases, liquids or solids can be handled with special coatings that will protect the materials and metals from corroding or breaking down.
A High Pressure Centrifugal as a Ventilator?
High Pressure Centrifugals are rarely used as ventilators or man coolers. This is due to the fact that high pressures that are created after being processed by the impeller wheel create unfavorable breathing environments exactly at the outlet.
By carefully managing and expanding the volume, High Pressure Centrifugals can be used as ventilation devices however. A careful selection of strong and tough materials should be considered when attaching ducting or connections at the inlet and outlet so that they don’t succumb to the high pressures or vacuums. Industrial ventilation systems for factories and human occupied spaces have to receive careful pressures and conditions. A High Pressure Centrifugal can be used in the case where the fan is located at a far distance from the required space for ventilation, or if there are many spaces to ventilate with a single fan. The fan would have to overcome many resistances such as corners in the ducting, dampers and pressures from each room. By expanding the duct and increasing the supply area, the pressure can be significantly lowered by the time the air arrives at its destination. For applications such as this, it is important that Custom built Centrifugals be chosen to create precise and careful conditions.
High Pressure Centrifugal fans, like the type that Custom Fans design, are great for applications such as pressure testing, dust removal and solid aeration. Dust collectors or bins can be connected at the outlet of a centrifugal to pull air from the inside of a room. The inlet of the fan would be attached to a duct which does the extraction through a round duct. Consult the relevant professionals that have years of experience designing these systems. The correct balancing and proper pre-engineering design ensures that High Pressure Centrifugal Fans operate at their best.