震波交互作用與能量聚焦之數值研究

Numerical Studies of Shock Waves Interaction and Energy Focusing

林永洲(Yong-Jhou Lin)

指導教授 ： 戴昌賢 ； 徐子圭

國立屏東科技大學/工學院/車輛工程系所/碩士(2012年)

https://doi.org/10.6346/NPUST.2012.00202

摘要

目前的儲存設備，無論是儲存電能、熱能、機械能、氫能都有其瓶頸亟待突破。在這些技術尚未成熟之前，直接將再生能源轉換成這些種能量並不恰當。高壓空氣能由於其大小可隨意調整，且容易保存，故是一種較易儲能的方式。前提是如何便宜的將再生能源轉換成高壓氣體能，以及如何地有效率地從高壓氣體能轉換成其他形式能量。
本研究主要透過數值模擬方式，探討震波反射、交互作用、聚焦等特性，將能量集中以方便使用及增加效率。為驗證程式的正確性，將數值模擬和理論計算結果做比對。本文針對震波反射、聚焦、共振等不同的案例作探討。由震波共振現象研究中發現，在連續震波生成後，可於某時間週期下，形成連續脈衝式震波，並提升其強度約一倍；於高壓空氣能推動壓板案例中，壓板重量除了造成的推進速度差異，推進移動伴隨著前方區域受壓形成震波，重量重者震波強度高、質量流率大，而震波產生的膨脹波會導致壓板移動方向的改變。透過本研究可了解高壓氣體能應用時所面臨的複雜現象，此結果可作為後續實驗及未來系統設計之參考。

關鍵字

再生能源 ； 高壓空氣能 ； 震波共振現象 ； 震波集中能量

並列摘要

Recently Storage devices, whether it is to store electrical energy, thermal energy, mechanical energy, hydrogen energy has its own bottlenecks need to overcome. Before these technologies are not yet mature, the direct conversion of renewable energy into these kinds of energy is not appropriate. High-pressure air because of its size can be adjusted freely and easily save, it is easier to storage. The premise is how changing the renewable energy into the high-pressure gas cheaply, and how efficiently from high-pressure gas can be converted into other forms of energy. This study carried out a technology applied the shock wave can be converted into the mechanical or the high-temperature thermal energy. Using the characteristics of shock wave reflection, interaction, and focusing concentrate energy to use easily and increase efficiency.
These studies mainly use the numerical method to investigate the shock wave interaction, reflection, and focusing in order to collect and concentrate the energy easily to use and improve the efficiency. For scheme validation, the numerical results of a shock tube compared with the theoretical value. There are lots of studied cases about the shock wave reflection, concentrating and resonance. In shock wave resonance study, the series pulse shock waves were occurred and concentrated by the trigger of the shock wave in a period time, and enhance its strength about twice. Through these studies to understand the complex phenomenon of high-pressure gas can be applied, they can be used as a reference for experiments and system design.

並列關鍵字

renewable energy ； high-pressure gas ； the resonance of shock wave ； shock wave concentrated energy

參考文獻

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