No. Each fan blade has an effective sweeping area. When two blades are too close together, the next blade will be affected by the wake of the previous one. In addition, each blade is very long and has a certain mass. If there are multiple blades, the stress on the tower will increase. Your design was used in early experiments with fans, and it was later proven that the current design is the most effective.
Why do wind turbines only have three blades? Isn’t it better to have more?
No matter the number of blades, the maximum efficiency of the blades in absorbing wind energy cannot exceed 59.3%. This can be calculated from aerodynamics. The design of three blades should consider material economy and stability. There are also many fans with two blades. It is thin and long to enlarge the wind sweeping surface. In fact, the blades are very thickhips and appear thin compared to their length.
With the changing times, the functions of these machines and equipment have been continuously improved, such as grain grinding. , water transport, electricity production, etc. Traditional wind turbines come in various shapes and designs, but they are all currently being replaced by the same design. Wind power, as a new clean and renewable energy source, has become a popular energy source in recent years. When you walk near the wind turbine and admire the view of the wind leaves spinning quietly under the blue sky and white clouds, are you also curious to know the difference between the 3 leaves and the 5 leaves of the wind turbine? wind turbine ?
As a new clean and renewable energy, wind energy has received great attention in recent years. When you walk near the wind turbine and admire theSeeing the wind leaves spinning quietly under the blue sky and white clouds, are you also curious to know the difference between the 3 leaves and the 5 leaves of the wind turbine?
To put it simply, three sheets are easy to balance, but if there are too many sheets, it will be difficult to balance and the cost will be high.
At the rated wind speed, the power generated is proportional to the swept area of the wind rotor, i.e. a wind rotor with 200 blades and a wind rotor with 1 blade can produce the same power.
The above figure shows that as the number of blades increases, the wind power utilization coefficient also increases, but in the process from 3 blades to 4 blades to 5 blades , the wind power utilization coefficient increases significantly, compared with the increase from 1 leaf to 2 leaves to 3 leaves, the increase is much smaller from the point of view ofcosts, the gain exceeds the loss.
So, the fewer blades a wind turbine has, the better?
First of all, the advantage of multi-blade fans is the higher torque conversion rate, but in terms of energy conversion rate, the efficiency of 4-blade and 5-blade fans is lower than that of 3-blade fans. blade fans.
The main reason is that the high resistance of multi-blade fans causes a considerable amount of turbulence which interferes with the rotation of the blades, thereby reducing the energy conversion rate.
It is therefore much better to choose 3 sheets than 4 or 5 sheets. (Well, the same goes for electric fans); Second, an insufficient number of blades will affect the efficiency of power generation.
In fact, there is currently a patent in Europe that has two leaves, placed vertically, which can double the effectiveness! However, the wheel hub2-blade has a special structure with a rocker structure, and the fatigue problem is worse than that of the 3-blade impeller.
In addition, the fewer blades, the higher the rated speed. When the speed reaches a certain level, the roundness of the blade tip becomes. The peripheral speed is very high, resulting in large wind resistance, and the drag torque limits the further increase in power production. energy and rotation speed. Therefore, it is not good to have too few blades. Three blades are mainly for good balance and low cost. After a long period of verification, they have become a common form of fan today.