Please use this identifier to cite or link to this item: `http://hdl.handle.net/11455/2457`
 標題: 氣壓水箭飛行動力之數值分析Numerical Analysis of Flight Dynamics for Gas-Ptessurized Waterjet Rocket 作者: 邱智宏Chiu, Chih-Hong 關鍵字: waterjet rocket;氣壓水箭;generalized power equations;intergrated Energy Method;通化總動力功率;能量積分法 出版社: 機械工程學系 摘要: 摘 要 對水火箭而言，內流場變化，箭體加速度，或是箭體外殼質量及水量等參數，均會影響飛行高度。本文將聯立通化動量方程式及總動力公率公式，來分析水火箭之飛行動力，並利用電腦數值積分方式輪迴運算，以模擬整個飛行過程且預測其射高。此種能量整合方法，不但同時處理水火箭之內外流場，更巧妙的利用等熵過程計算水火箭之總動力功率。此外，更對水噴完後之氣體效應進行探討，使水箭高度之預測更加精確。數值計算結果亦和實驗數據大致相符。如此可任意變化參數，分析其對射高的影響，如水火箭的外殼質量，無論在極輕或極重時都飛不高，而在給定的條件下，有一特定的外殼質量可以達到較佳的飛行高度。水火箭包含了架構簡單、環保、有趣且便宜等諸多特點。本文利用富含物理參數之總動力功率公式，以進行水火箭之飛行動力數值分析，不但可作提昇傳統火箭推進效率之低成本實驗工具，其豐富可變之參數，更具有探討研究噴射理論之高度學術價值。未來可嘗試使用輕薄金屬為箭體材料，以發展短程無煙反坦克飛彈。總之，對充滿潛力與憧憬的水火箭，本文奠定了其飛行動力分析設計的良好基礎。Abstract For a waterjet rocket, many parameters, such as the internal pressure, the shell mass, the air/water proportion, the size and shape of nozzle, all can affect the flight apex. In this research, the flight dynamic of waterjet rocket is analyzed by solving the momentum and the generalized power equation simultaneously to predict its flight histogram, computationally, and convolutionally. This integrated energy approach synthesizes both internal and external dynamics analysis together and elegantly takes full advantage of predictable power supply of the pressurized air in a waterjet rocket. Moreover, for better prediction of flight apex, the effect of pure air expulsion post waterjet is generally considered, too. The analysis results are reasonably agreeable with experimental flight data. By this way, we can arbitrarily change parameters to analysze the corresponding effects on flight apexes. For example, waterjet rocket cannot attain an optimal apex if its shell mass is either too heavy, or too light. Comparatively, the waterjet rocket is characterized by simplicity, environmental friendliness, interest, and minimal cost. Herein, we make use of generalized total kinetic power equation, which involves more physical parameters and effects to be manipulated. Hence waterjet rocket is a good model for propulsion analysis, experiment and education, due to abundance of very easily adjustable key parameters. Incidentally, the waterjet may have the potential as the power source for short-rang missile, say, antitank missile with absolutely no smoke to be detected. In conclusion, for a waterjet rocket as a potential and versatile propulsion model this research establishes a gracefully analysis and design foundation for its flight dynamics. URI: http://hdl.handle.net/11455/2457 Appears in Collections: 機械工程學系所