在石油能源日趨枯竭及環保意識上升的情況下，再生能源的開發已經受到相當的重視。在眾多再生能源之中，蘊藏量豐富的海洋波浪能被視為一項極具潛力的替代能源，然而其現階段在經濟上的競爭力受限於目前波浪能採集技術而不如其他已成熟發展的再生能源，如風能。因此，各沿岸大國正極力投資研發波浪能轉換裝置，以期在未來能善用這龐大的能源。
根據其工作原理，波浪能轉換裝置可分為三類，其中一類被稱為水柱震盪式。它是利用海洋週期的波浪來反覆壓縮／膨脹其腔室內空氣，從而驅動空氣壓縮機來產生電能。一般來說，目前最為廣泛被使用在水柱震盪式的空氣壓縮機為Wells壓縮機，但它現在依然還有許多在空氣動力方面的缺點尚未被解決，因此我們在概念上設計了一套非空氣動力的能量採集裝置試圖解決目前的困境。這個系統的概念是由上方週期驅動的空氣壓力來激發下方水槽液面產生水波，而水波造成鉸鏈側壁的擺盪，以致連接的發電機將其動能輸出為電能供人使用。
為了探討這個獵能系統，我們建立了一套物理及數學模型，利用數學方法來分析此系統，進而探討幾項系統特性：（1）在自然響應下的系統自然頻率與模態，（2）在受壓情況下，引發頻率共振區與停滯區的機制。具體而言，我們發現當驅動頻率接近其系統同型態之自然頻率時，側壁擺盪與發電機輸出電力會大幅上升，產生共振的現象。此外，在最佳化設計當中，我們發現了一條最佳直線，當我們將系統參數設計在這條線上時，將可以產生最大的電能。
此篇論文中，對於系統效能及特性求解所推導的一系列線性解析方法，不僅是為了分析此新設計的系統，同時也可望將這套數學解析方法應用在其它類似的波浪能轉換裝置。

In order to supply for ever-increasing energy demands of human and simultaneously preserve natural environment, it is of topmost priority to develop renewable energy resources. Among several renewable energy option, ocean-wave energy is regarded as a promising alternative on account of its abundant storage in the ocean. Accordingly, many coastal countries devote substantial financial support to the improvement of wave energy convertors (WECs).
Based on their working principle, the oscillating water column (OWC) is one type of WECs, which is mostly installed on shorelines. Moreover, the Wells turbine is the most frequently utilized power take-off component for OWC plants. However, there are a few challenges on aerodynamic problems which shall be conquered. We thus wish to explore the possibility of exploiting a non-aerodynamic power take-off device. Particularly, in this study, a model system incorporates a wave tank with two hinged side walls and electrical generators The basic idea is to specify a periodically varying pressure to excite surface waves in a water tank, which sequentially drive the hinged side walls into periodic oscillation, then being converted into electricity through electrical generators.
For investigation into this wave energy system, we construct a physical and mathematical model; then proceed to analyze this problem by analytical means. Several significant results reveal the characteristics of the model system: (a) two types of natural frequencies and mode shapes in natural response; (b) the mechanism of resonant regions and dead zones in its forced response. As the forcing frequency approaches the same type of natural frequencies, the oscillation of side walls and output power will be amplified tremendously. Furthermore, we discover an optimal line guiding us to design system with particular parameters so as to maximize the output power.
In this thesis, we construct a complete set of linearized analytical methods to evaluate performance and characteristics of our model system. It is not only worth analyzing this new conceptual design of wave energy system, but also expected to be applicable to the analysis of other similar WECs.

[1] Clément A, McCullen P, Falcão A, Fiorentino A, Gardner F, Hammarlund K, Lemonis G, Lewis T, Nielsen K, Petroncini S, Pontes MT, Schild P, Sjöström BO, Sørensen HC, Thorpe T (2002) Wave energy in Europe: current status and perspectives. Renew Sustain Energy Rev 6:405−431
[2] Dent CM (2013) Wind energy development in East Asia and Europe. Asia Eur J 11:211−230
[3] Thorpe TW (2000) The wave energy programme in the UK and the European wave energy network. In: Proceedings of the 4th European Wave Energy Conference, Aalborg, Denmark, pp 19−27
[4] Falcão AF de O (2010) Wave energy utilization: A review of the technologies. Renew Sustain Energy Rev 14:899−918
[5] Heath TV (2012) A review of oscillating water columns. Phil Trans R Soc A 370:235−245
[6] The Queen's University of Belfast (2002) Islay LIMPET wave power plant. Report of a research funded in part by the European Commission in the framework of the Non Nuclear Energy Program Joule III. Retrieved on 22 April 2015 from http://cordis.europa.eu/documents/documentlibrary/66628981EN6.pdf
[7] Folley M, Curran R, Whittaker T (2006) Comparison of LIMPET contra-rotating wells turbine with theoretical and model test predictions. Ocean Eng 33:1056−1069
[8] Count BM, Evans DV (1984) The influence of projecting sidewalls on the hydrodynamic performance of wave-energy devices. J Fluid Mech 145:361−376
[9] Torre-Enciso Y, Ortubia I, López de Aguileta LI, Marqués J (2009) Mutriku wave power plant: from the thinking out to the reality. In: Proceedings of the 8th European Wave and Tidal Energy Conference, Uppsala, Sweden, pp 319−329
[10] Chen Z, Yu H, Hu M, Meng G, Wen C (2013) A review of offshore wave energy extraction system. Adv Mech Eng 2013:623020, 9pp
[11] Falnes J (1999) Wave-energy conversion through relative motion between two single-mode oscillating bodies. ASME J Offshore Mech Arct Eng 121:32−38
[12] Yemm R, Pizer D, Retzler C, Henderson R (2012) Pelamis: experience from concept to connection. Phil Trans R Soc A 370:365−380
[13] He H, Qu Q, Li J (2013) Numerical simulation of section systems in the Pelamis wave energy converter. Adv Mech Eng 2013:186056, 8pp
[14] Hazra S, Bhattacharya S, Uppalapati KK, Bird J (2012) Ocean energy power take-off using oscillating paddle. In: Proceedings of the 2012 IEEE Energy Conversion Congress and Exposition, Raleigh, NC, USA, pp 407−413
[15] Gu Y, Zhao L, Huang J, Wang B (2012) The principle, review and prospect of wave energy converter. Adv Mat Res 347−353:3744−3749
[16] Hald T, Friis-Madsen E, Kofoed JP (2002) Hydraulic behaviour of the floating wave energy converter Wave Dragon. In: Proceedings of the 10th Congress of International Maritime Association of the Mediterranean (IMAM 2002), Crete, Greece, paper no 103
[17] Kofoed JP, Frigaard P, Friis-Madsen E, Sørensen HC (2006) Prototype testing of the wave energy converter wave dragon. Renew Energy 31:181−189
[18] Malara G, Arena F (2013) Analytical modelling of an U-oscillating water column and performance in random waves. Renew Energy 60:116−126
[19] Rezanejad K, Bhattacharjee J, Soares CG (2013) Stepped sea bottom effects on the efficiency of nearshore oscillating water column device. Ocean Eng 70:25−38
[20] Teixeira PRF, Davyt DP, Didier E, Ramalhais R (2013) Numerical simulation of an oscillating water column device using a code based on Navier-Stokes equations. Energy 61:513−530
[21] Ketabdari MJ, Khorasani F, Boreyri S, Karami V (2014) Numerical performance analysis of oscillating water column device using sea waves. Int J Environ Stud 71:840−849
[22] Rezanejad K, Bhattacharjee J, Soares CG (2015) Analytical and numerical study of dual-chamber oscillating water columns on stepped bottom. Renew Energy 75:272−282
[23] Havelock TH (1929) Forced surface-waves on water. Phil Magazine 8:569−576
[24] Hyun JM (1976) Theory for hinged wavemakers of finite draft in water of constant depth. J Hydronautics 10:2−7
[25] Hyun JM (1976) Simplified analysis of a plunger-type wavemaker performance. J Hydronautics 10:89−94
[26] Wu YC (1991) Waves generated by a plunger-type wavemaker. J Hydraulic Research 29:851−860
[27] Billingham J, King AC (2001) Wave motion. Cambridge University Press.
[28] The Queen's University of Belfast (2002) Islay LIMPET wave power plant. Report of a research funded in part by the European Commission in the framework of the Non Nuclear Energy Program Joule III. Retrieved on 22 April 2015 from
http://cordis.europa.eu/documents/documentlibrary/66628981EN6.pdf