New Concepts, Insights, and Methods in Aerodynamic Design of Shell-Less Centrifugal Fans.

With the advancement of modern aerodynamic design methods for shell-less centrifugal fans, we have encountered new challenges during the development of high-performance fans, particularly in our interactions with frontline production management technicians. Simultaneously, the process of addressing these challenges often sparks fresh ideas and approaches, continuously driving the evolution of contemporary design methodologies. Next, we will briefly introduce the selection of aerodynamic design methods for airflow, hoping to deepen our understanding. The aerodynamic design of shell-less centrifugal fan equipment is primarily based on the design flow rate requirements provided by the user. Moreover, the default operating condition is set to achieve high efficiency under such conditions. However, analysis of actual applications reveals that the operating point for many shell-less centrifugal fan units does not align with the aerodynamic design flow rate. The deviation in direction and magnitude is related to the specific speed. Typically, fans with specific speeds below 27—commonly termed low-specific-speed fans—often exhibit flow rates exceeding the original design conditions. Moreover, the deviation becomes more pronounced as the specific speed of the shell-less centrifugal fan decreases. Fans with medium specific speeds generally operate close to their original design conditions. When the specific speed exceeds 55, the operating flow rate falls below the original design flow rate. For such scenarios, we can initially adopt aerodynamic design methods when selecting start-up design approaches. Specifically, when designing shell-less centrifugal fans, flow rate design and total pressure aerodynamic design should be conducted reasonably based on different user requirements. While optimizing design performance, the non-design performance of shell-less centrifugal fan equipment should also be considered. Are you aware of the five major performance advantages of backward-curved double-inlet centrifugal fan equipment? The application of backward-curved double-inlet centrifugal fans should be understood, as this type of fan equipment offers numerous advantages. Precisely for this reason, it is increasingly attracting attention from a wide range of manufacturing enterprises. So, do you know the primary superior performance characteristics of this equipment in practical applications? Let's analyze this issue to help everyone better understand backward-curved double-inlet centrifugal fans. Advantage 1: High Productivity Compared to alternatives, backward-curved double-inlet centrifugal fans demonstrate exceptional productivity. This stems from their specialized design: utilizing high-speed rotational force for self-suspension and employing high-pressure forming with chromium-nickel alloy materials. This achieves high operational efficiency with speeds reaching 100,000 RPM, accommodating diverse working environments. Second advantage: Low noise This high-speed centrifugal fan not only ensures high efficiency but also operates with minimal noise. This is achieved by directly connecting the high-efficiency impeller and ultra-high-speed motor via air bearings, eliminating the need for gearboxes and lubrication systems. The absence of mechanical contact and vibration results in low operational noise, eliminating the requirement for soundproof enclosures. Third advantage of backward-curved double-inlet centrifugal fans: Zero wear. This stems from the high-speed shaft operating without contact friction during normal operation, preventing component wear and eliminating power loss over extended use. Fourth advantage of backward-curved double-inlet centrifugal fans: Zero contamination. These high-speed centrifugal fans require no lubricating oil during operation, achieving true contamination-free performance. Fifth advantage of backward-curved double-inlet centrifugal fans: Extended service life. These fans feature ultra-high-strength impellers and utilize air-suspension bearings that eliminate wear and lubrication requirements. Consequently, they require minimal maintenance during prolonged operation, ensuring significantly extended service life.