本研究首先設計一易受風致扭轉之單自由度氣彈結構，作為承受風力作用之主體，並於其內部配置多元壓電調諧振動能量擷取裝置(Piezoelectric Multiple Tuned Vibration Energy Harvesters， Piezo-mTVEHs)，整合形成壓電式扭轉型無扇葉風力發電機(Piezoelectric Torsional Bladeless Wind Turbine， Piezo-TBWT)。氣彈結構之上部以剛性鈍體作為受風結構；下部則由四根片狀柱支撐作為扭轉基座，藉由將各柱體之強軸朝向主結構幾何中心排列之特殊配置，確保結構第一振態為扭轉模態，且於任意風向下皆能產生振動。考量Piezo-mTVEHs僅能單向振動變形，故將各裝置環繞結構扭轉剛心對稱排列，並設計其與結構扭轉頻率相調諧，使其可與結構扭轉產生之切線方向基底加速度共振，進而擷取振動能量並轉換為電能。於數值模型方面，首先建立單顆Piezo-TVEH之數值模型，再以多顆配置組成Piezo-mTVEHs並結合於扭轉結構中，整合為Piezo-TBWT之運動方程式並改寫為狀態空間形式。於能量轉換效率指標上，推導電致阻尼比之解析式，探討其作為指標之可行性，並與特徵分析所得之壓電阻尼比比較，結果顯示，解析式可有效估計最佳外接電阻，可作為設計之初步依據。接著就外接質量比值、長度比值及基底層厚度等設計參數進行敏感度分析，探討各參數對壓電阻尼比之影響，據以選定Piezo-TVEH裝置尺寸。最後於扭轉結構中裝設三顆 Piezo-TVEH，並採相同參數配置，以避免反應集中於單顆裝置，使各裝置之作動能力得以充分發揮，再利用直接搜尋法以平均功率最大化為目標，求得最佳末端質量與外接電阻。於邊界層風洞中，首先利用特徵系統實現演算法(ERA)識別扭轉結構與Piezo-mTVE Hs之頻率及阻尼比，再據以推算結構與壓電材料參數，作為後續分析依據。考量剛性鈍體為方形斷面，其扭轉反應隨風向角而異，因此進行多風向受風實驗，選定結構扭轉反應最顯著之風向角，再裝設Piezo-mTVEHs進行能量擷取實驗。實驗結果顯示，各風速下之轉換電能比例穩定維持於約42–43%，與阻尼比推估能量分配比例所得之轉換比例41.56%相近；且於風速4.0 (m/s)時達最大平均擷取功率約 0.24(mW)，驗證本研究所建立Piezo-TBWT數值模型之準確性，並證實Piezo-TBWT於真實風力作用下確具擷取扭轉振動能量並轉換為電能之能力。;This study first develops a single-degree-of-freedom aeroelastic structure designed to undergo wind-induced torsional vibration and serve as the primary structure subjected to wind loading. Piezoelectric Multiple Tuned Vibration Energy Harvesters (Piezo-mTVEHs) are installed within the structure and integrated with it to form a Piezoelectric Torsional Bladeless Wind Turbine (Piezo-TBWT). The upper part of the aeroelastic structure consists of a rigid bluff body exposed to the wind， while the lower part is supported by four flat-plate columns that form the torsional base. By orienting the strong axis of each column toward the geometric center of the main structure， the structural configuration ensures that the fundamental mode is torsional while allowing the structure to develop a dynamic response to wind from any direction. Considering that the Piezo-mTVEHs are capable of vibration in a single direction only， they are arranged symmetrically arranged about the torsional center of rigidity. They are tuned to the structural torsional frequency to resonate with tangential base acceleration induced by structural torsion， thereby enabling vibration energy harvesting and conversion into electrical energy. For the numerical model， a single Piezo-TVEH model is first established， then multiple units are assembled into Piezo-mTVEHs and integrated into the torsional structure to formulate the Piezo-TBWT in state-space form. An analytical expression for the electrically induced damping ratio is derived and compared with the piezoelectric damping ratio obtained via eigenvalue analysis， serving as a preliminary tool for estimating the optimal resistance. A sensitivity analysis on three design parameters—external mass ratio， length ratio， and base-layer thickness—is then used to determine the Piezo-TVEH dimensions. Finally， three Piezo-TVEH units are installed in the torsional structure with identical parameter configurations to prevent uneven response distribution among the devices and to ensure full utilization of each device’s actuation capability. The direct search method is then employed， with average power maximization as the objective， to determine the optimal tip mass and external resistance. In the boundary layer wind tunnel， the Eigensystem Realization Algorithm (ERA) is first employed to identify the natural frequencies and damping ratios of the torsional structure and Piezo-mTVEHs， from which the structural and piezoelectric parameters are subsequently determined for further analysis. As the bluff body has a square cross-section and its torsional response varies with wind direction， wind tests under multiple angles are conducted to identify the wind direction that induces the most significant torsional response. The Piezo-mTVEHs are then installed for energy harvesting experiments under the selected wind direction. The energy conversion efficiency remains stable at approximately 42–43% across all wind speeds， which is close to the 41.56% estimated from the damping ratio. A maximum average harvested power of approximately 0.24 (mW) is achieved at a wind speed of 4.0 (m/sec)， thereby validating the Piezo-TBWT model and confirming its energy harvesting capability under real wind conditions.
