Result and Conclusion

A detailed review of various bio-inspired designs of fan blades is thoroughly analyzed in the current study, with serrated edges, half perforated edges and slightly tilted edges being some of the designs that were inspired by the owl wings morphology that has been associated with silent flight. It was aimed at studying the aerodynamic performance (airflow, velocity, pressure) and the acoustic behavior (noise levels) with the highest level of CFD computations and with the help of acoustic modeling.

Results of Reference Modal

Result Table

Noise Performance:

There was great heterogeneity in the design of noise generation. The highest level of noise (63.5 dB) was registered in the serrated edge design, and this could be attributed to the fact that serrations increase the turbulence due to the sub-division of the airflow into smaller vortices. This implies that the serrations in nature used to mitigate noise can be applied in fan blades easily without causing any negative impact; however, this does not necessarily apply to any optimization done on serrations.

The design of half-perforated edges presented less noise (55 dB) than the serrated one, which proved its ability to flatten the airflow and reduce pressure variability due to controlled airflow flow in the perforations. There is still some turbulent noise though, which shows that a tradeoff between noise and aerodynamic.performance.exists.
The lowest noise value (49.5 dB) was obtained with the tilted edge design, which highlights its effectiveness in the control of vortex formation and tremendous reduction of aerodynamic sound. Figure 15 shows the analysis results of the same. This renders the tilted edge design the most promising in the situation where noise pollution is a serious issue of concern.

Airflow and Velocity:

The serrated edge design produced high turbulence; however, this also produced the lowest airflow (2.52 kg/s) which can be attributed to the low overall flow caused by dissipative turbulence in the blades. Contrarily, the half-perforated design recorded the maximum airflow (4.14 kg/s). It is indicated that more air moves as the velocity is moderate, though due to the perforations, more air moves in and out through the blade structure because it is perforated. The edge design with a tilted edge was also very accommodating (3.59 kg/s) of significant airflow indicating that it had a maintained aerodynamic efficiencydespitethel.owervelocity.
Blades with serrations and half-perforations were near the baseline fan (22.5 m/s and 23 m/s, respectively) and the tilted edges design was significantly less (15.4 m/s) suggesting trade-offs between noise suppression and flow velocity.

Pressure Distribution:

Velocity trends were accompanied by pressure caused by the blades. Tilted edge design showed the minimum pressure (53.3 Pa) which is in line with the fact that the design had low velocity SHOWN IN Figure 16. Serrated and half-perforated designs were intermediate pressures (~91-93 Pa), which were lower than standard blades as they caused more disturbance of flow or partial flow pass-through.

Comparative Insights

The trade-offs of each design are different: Serrated edges enhance the noise and decrease the flow of air that means that direct biological modeling must be adapted attentively. Half-perforated edges are much more efficient in airflow and are applicable in cases where high ventilation is needed at moderate noise and complexity of manufactures. Tilted edges have excellent noise-reduction capabilities, and they are not accompanied by poor airflow, so they can be used in noise-sensitive locations.

Comparison Table

The combination of biomimetic principles makes it possible to adjust the properties of tuning fan blades to the requirements of the application. Optimized geometry based on nature, as well as engineering, is needed in noise reduction, airflow improvement, and pressure balancing. Alternative acoustic simulation models in ANSYS Fluent were effective in capturing noise characteristics which proved design decisions. This research is a solid basis to be further tested experimentally, enhanced materials to be included and a combination of several features of biomimetic design to make next generation fan blades that balance between energy efficiency and acoustics comfort. This summary is a summary of observed results characterizing aerodynamic and acoustic performance to features of bio-inspired blade designs and results of the simulations performed.

Coclusion

The paper is a comparative study of three promotional designs of fan blades based on the morphology of an owl wing: serrated edges, half-perforated edges, and tilted edges. Among them, the design with the tilted edges proved to be the most effective in terms of noise reduction without the loss of good airflow because of this, it was particularly applicable in a noise-sensitive environment. The half-perforated design was superior in airflow maximization, but with average noise and increased complexity and cost of manufacture. The serrated edge design, although a biological inspiration, led to a noisier and resistance-to-airflow design, suggesting that bio-inspiration needs careful consideration to the engineering implementation. Reduction of material and manufacturability also played a critical role; the perforated design, though having its advantages in a performance, is more difficult to fabricate and more expensive than the other designs. Generally, this study also points out key trade-offs that exist between acoustic comfort, aerodynamic performance, and economic feasibility that need balancing depending on the needs of a particular application. Even though the outcomes are encouraging, more experimental verifications, material advancements, and optimization that integrates various biomimetic characteristics in a single design are some of the main steps to be taken in the future. This will open the door to the creation of next-generation ceiling fans that will integrate efficient airflow, less noise and a sustainable production process, which will be beneficial to thermal comfort and energy efficiency of indoor environment.