本研究以實驗方法測試人工瓣膜流場性能，探討單葉人工瓣膜於不同葉瓣開口角度及不同流量下的壓力損失特性，以提供人工心臟系統動力模型建立與控制律設計之用。人工瓣膜流場特性圖的製作是在擬定常（Quasi-steady）假設下繪製而成，圖中每條特性曲線均為在定常流場（Steady flow）的情況下所量測到的流場參數。在本研究中採用兩個不同尺寸的Medtronic Hall valve（Model A7700）作為測試之用，分別為27AHK（孔徑直徑22mm）及29AHK（孔徑直徑24mm）。由所得之特性圖可知在同一葉瓣開口角度下的特性曲線其壓力損失隨著流量增加而增加，且在同一流量下，壓損隨著葉瓣開口角度的減少而增加。在本研究中主要以瓣膜孔徑有效面積（Effective Orifice Area, EOA）及Discharge Coefficient 作為分析人工瓣膜性能之依據。研究結果分別獲得MH-27AHK與MH-29AHK之EOA為2.90 cm2及3.55 cm2，及其Discharge Coefficient分別為0.76及0.78。

This research focuses on the performance evaluation of two monoleaflet prosthetic aortic heart valves. Flow characteristics in terms of pressure drop for these prosthetic heart valves at different opening angles and flow rates are studied. These results will be used to construct the dynamic model and to design the control law of an artificial heart system. The flow characteristics maps of the valves are constructed under the quasi-steady assumption. Each characteristic curve is obtained from a steady-state measurement. In this study, we use two Medtronic Hall valves (Model A7700) as the testing subjects, each with 22mm (27AHK) and 24mm (29AHK) in diameter, respectively. The results show that the pressure drop across the valve is in proportion to the flow rate, which increases with the increased flow rate for the same occluder opening angle. Under the same flow rate condition, however, the pressure drop increases as the opening angle decreases. Flow performance of the prosthetic valves is measured using the parameters of effective orifice area (EOA) and discharge coefficient . The results show that the EOAs of the MH-27AHK and MH-29AHK valves are 2.90 cm2 and 3.55 cm2, and the corresponding discharge coefficients are 0.76 and 0.78, respectively.

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