In daily life, fans are common household appliances, and their design details are often overlooked by us. However, one of the eye-catching features is that most fans have an odd number of blades, especially three- or five-blade designs. relatively common. Behind this phenomenon, there are actually profound physical principles, engineering practices and user experience considerations. This article will explore the reasons why most fan blades are of odd-numbered design.
- Optimization of aerodynamics
Reduce resonance and vibration: The working principle of the fan is to promote the flow of air through the rotation of the fan blades, thereby generating wind. During the rotation process, the fan blades will periodically cut the air and generate aerodynamic force. If the number of fan blades is an even number and arranged in such a way that the aerodynamic forces generated by each pair of fan blades are superimposed on each other, resonance may occur. Resonance will not only cause the fan to vibrate more and produce noise, but may also damage the motor and other mechanical components. The odd-number fan blade design can effectively avoid this symmetrical resonance, make the aerodynamic force distribution more even, and reduce vibration and noise.
Improved aerodynamic efficiency: Odd-number fan blade designs tend to be more aerodynamically efficient. They can guide air flow more effectively, reducing mutual interference and eddy losses between air flows. For example, a three-blade fan can form a relatively stable airflow field when rotating, making the wind force more concentrated and uniform, thus improving the overall aerodynamic efficiency.
- Considerations of engineering manufacturing
Simplified manufacturing process: The design of odd-numbered fan blades is simpler and more straightforward during the manufacturing process. It reduces the complexity of mold design and reduces production costs. At the same time, an odd number of fan blades makes it easier to achieve dynamic balance, reducing the difficulty and time cost of debugging during the manufacturing process. In addition, the assembly and maintenance of odd-numbered fan blades are also more convenient, reducing overall operating costs.
Enhanced structural stability: The layout of the odd blades helps enhance the structural stability of the fan. Each fan blade experiences unique forces and moments during rotation, which prompts designers to pay more attention to the material selection, thickness distribution, and connection methods of the fan blades. Through reasonable structural design and material selection, it can be ensured that the fan still maintains stability and durability even when rotating at high speed.
- Improvement of user experience
Reduced Noise: As mentioned earlier, the odd-numbered fan blade design helps reduce resonance and vibration, thereby reducing the noise when the fan is running. This is especially important for users who pursue a quiet living environment.
Improve comfort: In addition to reducing noise, the odd-number fan blade design can also improve the comfort of the fan’s air supply. By optimizing the airflow distribution and wind intensity, the wind blown by the fan can be made softer and more uniform, reducing the discomfort when blowing directly to the human body.
- Market and design trends
Market Acceptance: For a long time, the odd-number fan blade design has gained wide acceptance and recognition in the market. Consumers have gradually developed a preference and trust for three-blade or five-blade fans. This market trend has also prompted manufacturers to prefer odd-numbered fan blade designs when designing new products.
Design aesthetics: Although beauty is not the decisive factor, the odd-numbered fan blade design often gives people a simple and harmonious aesthetic. They are arranged in an asymmetrical but orderly manner, in line with the aesthetic trends of modern design.
Fan blades of various shapes and materials of UnitedStar
1) Horn shaped fan blade: it has larger air supply range, larger air volume and softer air supply than other fans, because the horn shape has small area, large angle and small resistance.
- PP fan blade is produced by injection molding with (polypropylene) new material, with good quality, low noise, high safety, not easy to deform, light weight and power saving.
1) Low noise.
The metal blades are generally thin, because the whole load will increase when they are heavy, while the plastic blades are generally thicker than the blades, and they are easy to break when they are light. The sound of cutting air by metal sheet is much louder than that of thick plastic blade, and the sound is even louder when there is slight shaking.
2) High safety
Metal blades are easy to scratch hands during maintenance. When it is not installed properly or suddenly falls off during use, or something is accidentally involved during rotation, the blade is easy to break and fly out, so it is dangerous for the metal blade to fly out.
3) Not easy to deform
The plastic blades are all cast by fixed molds without deformation. Unless baked by fire, the metal blades are easy to deform due to their good flexibility, wind resistance, weather change and other factors.
- ABS fan blade: hard, easy to color, with 90% high gloss, non-toxic, tasteless, low water absorption
- Aluminum alloy fan blade: the material is harder than plastic, and the air outlet is stable and strong. More durable than plastic, aging resistant, long-term use without deformation.
If it is not a high-power fan, the advantages of plastic are higher than the cost performance ratio; If the power is large, the performance advantages of aluminum alloy will be clearly reflected.
For example, this self-designed fan blade of UnitedStar has large air volume, low noise, energy saving and power saving, and is not easy to deform. At present, it has been recognized by many overseas customers.
Fan blade manufacturer UnitedStar have launched a new multi-blade, which can be placed in any fans, if you like we can customized the fan you need.
To sum up, the reason why most fan blades choose odd-number designs is mainly due to the optimization of aerodynamics, engineering manufacturing considerations, improvement of user experience, and market and design trends. This design choice not only reflects the engineers’ deep understanding of physical laws and strict control of product performance, but also satisfies consumers’ pursuit of comfort, quietness and beauty. In the future, with the continuous advancement of technology and the continuous innovation of design concepts, there may be more new breakthroughs and changes in the design of fan blades, but the advantages of odd-numbered designs will still be reflected and applied in many aspects.
