超空蝕效應

超空蝕效應（Supercavitation）利用空穴效應製造了含有氣體的泡沫膜，而這個泡沫膜大到足以包含物體本身，使其在泡沫膜中行駛減少摩擦力，來達到極高速度。除去移動方向的部分，物體因為不與水接觸，基本上不會與水摩擦，因此能在水中超高速前進。目前的應用主要限於自動推進武器（如火箭、魚雷、導彈等），但理論上，該技術可以擴展到包括車輛、飛機和潛艇等載具。

**物理原理**
在水中，如果水的壓力低於蒸氣壓時，就會產生空穴。當水流過一個移動金屬物件的尖銳轉角，被加到較高的速度時，壓強會迅速降至低於蒸氣壓的水平，此時超空蝕效應便會發生。
常見於輪船螺旋槳和泵槳葉的邊緣。水越深（水壓越高），外界壓強和蒸氣壓的差距越大，流體被加速時就越不容易產生超空蝕現象。

**參考資料**
Office of Naval Research (2004, June 14). Mechanics and energy conversion: high-speed (supercavitating) undersea weaponry (D&I). Retrieved April 12, 2006, from http://www.onr.navy.mil/ date=20210503074430 
*Savchenko Y. N. (n.d.). CAV 2001 - Forth Annual Symposium on Cavitation - California Institute of Technology Retrieved April 9, 2006, from https://web.archive.org/web/20060215234514/http://cav2001.library.caltech.edu/159/00/Savchenko.pdf
*Hargrove, J. (2003). Supercavitation and aerospace technology in the development of high-speed underwater vehicles. In 42nd AIAA Aerospace Sciences Meeting and Exhibit. Texas A&M University.
*Kirschner et al. (2001, October) Supercavitation research and development. Undersea Defense Technologies
*Ashley, S. (2001, May). Warp drive underwater. Scientific American
*Miller, D. (1995). Supercavitation: going to war in a bubble. Jane's Intelligence Review. Retrieved Apr 14, 2006, from http://www.janes.com/ date=20070228153854 
*Graham-Rowe, & Duncan. (2000). Faster than a speeding bullet. NewScientist, 167(2248), 26-30.
*Tulin, M. P. (1963). Supercavitating flows - small perturbation theory. Laurel, Md, Hydronautics Inc.

**參考書目**
Gertz, Bill (August 23, 2001). "Russian book sheds light on missile". Washington Times: p. A.4.  
*Office of Naval Research (2004, June 14). Mechanics and energy conversion: high-speed (supercavitating) undersea weaponry (D&I). Retrieved April 12, 2006, from http://www.onr.navy.mil/ date=20210503074430 
*Savchenko Y. N. (n.d.). CAV 2001 - Forth Annual Symposium on Cavitation - California Institute of Technology Retrieved April 9, 2006, from https://web.archive.org/web/20060215234514/http://cav2001.library.caltech.edu/159/00/Savchenko.pdf
*Hargrove, J. (2003). Supercavitation and aerospace technology in the development of high-speed underwater vehicles. In 42nd AIAA Aerospace Sciences Meeting and Exhibit. Texas A&M University.
*Kirschner et al. (2001, October) Supercavitation research and development. Undersea Defense Technologies
*Ashley, S. (2001, May). Warp drive underwater. Scientific American
*Miller, D. (1995). Supercavitation: going to war in a bubble. Jane's Intelligence Review. Retrieved Apr 14, 2006, from http://www.janes.com/ date=20070228153854 
*Graham-Rowe, & Duncan. (2000). Faster than a speeding bullet. NewScientist, 167(2248), 26-30.
*Tulin, M. P. (1963). Supercavitating flows - small perturbation theory. Laurel, Md, Hydronautics Inc.

**外部鏈接**
 Empiredate=20081121175136  — Science fiction website centered around envisaged supercavitation technology- Diehl BGT Defence's "Barracuda" - a german supercavitating Torpedo- DARPA Underwater Express Program- Global Security.org on Supercavitation date=20170420125335 - Supercavitation Research Group at the University of Minnesota date=20190618132153 - How to Build a Supercavitating Weapon, Scientific American