Mechanical Engineering Department, Khalifa University of Science and Technology, Abu Dhabi, UAE.
Mechanical Engineering Department, University of Engineering and Technology, Lahore, Pakistan.
PLoS One. 2024 Jun 10;19(6):e0304489. doi: 10.1371/journal.pone.0304489. eCollection 2024.
Flow-induced vibrations (FIV) were considered as unwanted vibrations analogous to noise. However, in a recent trend, the energy of these vibrations can be harvested and converted to electrical power. In this study, the potential of FIV as a source of renewable energy is highlighted through experimental and numerical analyses. The experimental study was conducted on an elastically mounted circular cylinder using helical and leaf springs in the wind tunnel. The Reynolds number (Re) varied between 2300-16000. The motion of the cylinder was restricted in all directions except the transverse direction. The micro-electromechanical system (MEMS) was mounted on the leaf spring to harvest the mechanical energy. Numerical simulations were also performed with SST k-ω turbulence model to supplement the experiments and were found to be in good agreement with the experimental results. The flow separation and vortex shedding induce aerodynamic forces in the cylinder causing it to vibrate. 2S vortex shedding pattern was observed in all of the cases in this study. The maximum dimensionless amplitude of vibration (A/D) obtained was 0.084 and 0.068 experimentally and numerically, respectively. The results showed that the region of interest is the lock-in region where maximum amplitude of vibration is observed and, therefore, the maximum power output. The piezoelectric voltage and power output were recorded for different reduced velocities (Ur = 1-10) at different resistance values in the circuit. It was observed that as the amplitude of oscillation of the cylinder increases, the voltage and power output of the MEMS increases due to high strain in piezoelectric transducer. The maximum output voltage of 0.6V was observed at Ur = 4.95 for an open circuit, i.e., for a circuit with the resistance value of infinity. As the resistance value reduced, a drop in voltage output was observed. Maximum power of 10.5μW was recorded at Ur = 4.95 for a circuit resistance of 100Ω.
流致振动（FIV）被认为是类似于噪声的不期望的振动。然而，在最近的趋势中，可以利用这些振动的能量并将其转换为电能。在这项研究中，通过实验和数值分析强调了 FIV 作为可再生能源的潜力。实验研究是在风洞中使用螺旋弹簧和叶片弹簧对弹性安装的圆形圆柱体进行的。雷诺数（Re）在 2300-16000 之间变化。圆柱体的运动在除横向以外的所有方向上都受到限制。微机电系统（MEMS）安装在叶片弹簧上以收集机械能。还使用 SST k-ω 湍流模型进行了数值模拟，以补充实验，并发现与实验结果吻合良好。流动分离和涡旋脱落会在圆柱体中引起空气动力，从而导致其振动。在本研究中的所有情况下都观察到 2S 涡旋脱落模式。实验和数值上分别获得的最大无量纲振动幅度（A/D）为 0.084 和 0.068。结果表明，感兴趣的区域是锁定区域，在该区域中观察到最大振动幅度，因此输出最大功率。记录了不同电路电阻值下不同缩尺速度（Ur = 1-10）下的压电电压和功率输出。观察到随着圆柱体振动幅度的增加，由于压电换能器中的高应变，MEMS 的电压和功率输出增加。在开路（即电阻值无穷大的电路）下，观察到最大输出电压为 0.6V，Ur = 4.95。随着电阻值的降低，观察到电压输出下降。在 Ur = 4.95 时，记录到电路电阻为 100Ω 时的最大功率为 10.5μW。
