本論文主要探討二維合成噴流致動器於薄膜及腔體共振下的基本特性、再運用合成噴流的特性於低雷諾數下探討NACA633018機翼的空氣動力特性，本論文所使用的實驗設備有風洞、熱線測速儀、六力平衡儀與雷射位移計等四項。
為了探討二維合成噴流的基本特性，實驗參數採用多種波形激擾、電壓激擾及頻率激擾，為找出有效控制參數，發現有兩個共振頻率發生於40Hz和160Hz，分別為薄膜共振頻率與腔體共振頻率，薄膜共振頻率不受不同波形、不同輸出電壓和出口面積變化而改變，腔體共振頻率也不受波形、電壓變化的改變，但僅受出口面積變化而改變，薄膜共振下，無因次化史脫克長度(dimensionless stroke length)與雷諾數(Reynolds number)的一次方成正比，就腔體共振而言，無因次化史脫克長度(dimensionless stroke length)與雷諾數(Reynolds number)的1.5次方成正比，有效頸口長度(the effective neck length, )，它並非是一個固定不變的常數，它與出口面積的三分之二次方成正比，值得注意的是，隨著四種不同的電壓激擾，其最大噴出速度和平均噴出速度均與腔體共振頻率的-1.5成正比。希望這些實驗結果對設計合成噴流運用其他領域的控制是有幫助的。
運用合成噴流的特性，運用控制NACA633018機翼上表面流場，研究其空氣動力特性，實驗安排主要使用一系列壓電片驅動的合成噴流致動器，埋入翼弦線的12%位置的NACA633018機翼並沿著翼展激擾來向流，以實驗研究其流場分離與空氣動力特性，本次實驗使用低速開放式風洞，當合成噴流致動器尚未開啟前，NACA633018機翼於雷諾數80000有遲滯現象，空氣動力特性很不穩定，而雷諾數120000無發現任何遲滯現象，故實驗所採用的雷諾數分別為80000和120000。雷諾數8×104時自由流流過NACA633018機翼時，流場於層流開始分離前，啟動合成噴流致動器擾動上表面機翼周圍流場，其擾動能量會影響機翼上表面的下游邊界層發展，消弭或減少機翼上表面的分離泡，其升力、阻力有明顯增加和減少，阻力效應隨雷諾數增加有明顯減少，但升力隨雷諾數增加有減少效應。

The dissertation major studies the fundamental characteristics of an isolated two-dimensional synthetic jet actuator ( SJA ) under both resonances of diaphragm and cavity. Then it is to explore the aerodynamic performance of NACA633018 wing with these characteristics of synthetic jet. The experimental facilities include an open-type low speed wind tunnel, hot-wire anemometer, six-component external force balance and laser displacement sensor etc.
In order to investigate the fundamental characteristics of two-dimensional SJA, the various excitation waveforms, excitation voltages and excitation frequencies are used as experimental parameters. It has to find out the effective parameters of control for the synthetic jet actuator. The experiment are found that the fundamental characteristics of two-dimensional synthetic jet actuator (SJA) and two resonance frequencies are found at 40 Hz and 160 Hz, which are resonance of diaphragm and cavity resonance, respectively. The former is independent of various excitation waveforms, excitation voltages and the exit area of an orifice. The latter is only associated with the exit area of an orifice. The dimensionless stroke length is proportional to the Reynolds number for resonance of diaphragm at various excitation voltages. For the cavity resonance, the important result here is that the dimensionless stroke length ( ) is proportional to at all four different voltages of excitation and the effective neck length ( ) doesn’t keep constant with the varying exit area of orifice. That is, the increases linear with the increasing . It is worthy to note that the relation between the maximum ejection velocity ( ) and the resonance frequency of cavity ( ) is at various voltages of excitation. Both and are inversely proportional to the in our research. These experimental results are expected to be useful for designing a synthetic jet actuator to do other applications.
Second part in the experiment, it experimentally studies that the flow separation and aerodynamic performance of a NACA633018 wing using a series of piezoelectric-driven disks, which are located at 12％ chord length from the leading edge to generate a spanwise-distributed synthetic jets to excite the passing flow. There is a hysteresis loop for the lift coefficient of the NACA633018 wing without excitation of the SJAs for a Reynolds number of 80000. On the contrast, it is not found any hysteresis loop on the surface of the NACA633018 wing at a Reynolds number of 120000. The experiment is conducted in an open-type wind tunnel with Reynolds numbers (Re) of 80000 and 120000, respectively, based on the wing chord. The oscillations of the synthetic jet actuators (SJAs) disturb the neighboring passage flow on the upper surface of the wing before the laminar separation takes place. The disturbances of energy influence the downstream development of boundary layers to eliminate or reduce the separation bubble on the upper surface of the wing. Significant lift increase and drag decrease are found at the tested Reynolds number of 80000 due to the actuators excitation. Furthermore, the effect of drag also reduces significantly with increasing Reynolds number, but the increase on lift is reduced with the Reynolds number increased.

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