Researches in Thermal Laser for a System of Cascading Energy Conversion into Light, Motive Energy and Thermal Energy

热激光器光、动能、热能级联能量转换系统的研究

• 批准号: 14205111
• 负责人: HASATANI Masanobu
• 金额: $ 32.53万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14205111/
• 关键词: Thermal laser; Cascading energy conversion; Population inversion; Super sonic fluid; O_2-enriched combustion; 熱レーザー; 酸素富化燃焼

A cascading energy-conversion-system which transforms a high-temperature and high-pressure energy generated by a combustion into three modes energy is proposed. These energy modes are laser amplification, motive energy and thermal one. In this research, the required conditions are extracted to establish the three modes energy-conversion-system and preliminary works in the amplification of the thermal laser have been investigated. The problems in the system are focused into two points. Because of installation of a gas turbine behind the laser equipment, requirements of the combustion temperature and the pressure for an amplification of the infrared laser caused by a population inversion of CO_2 are completely dissimilar with the conditions of general gas dynamic laser. Other one is decrease of CO_2 molecule in population inversion. This is why an increase of H_2O fraction in a laser medium causes deactivation of exited CO_2 molecules although mixtures of CO_2, N_2, H_2O are generated co … More ntinuously with a combustion reaction of hydrocarbons. Experimental and theoretical researches in an identification of CO_2 population inversion required for the infrared laser amplification were investigated. Results achieved are shown as follows. The gas flows quickly through a nozzle at supersonic speed, which forces the translational temperature to drop to a lower value. In the results, the vibrational temperature of the lower level being close to the translational temperature, while the vibrational temperature of the upper level is close to pre-expansion temperature. An amplification of 10.6 μm infrared light is investigated experimentally with the laser medium which is produced from combustion of CH_4 in O_2-enriched field. O_2-enriched combustion is adopted as a method that produces high temperature-high pressure gas easily. Plus gains are identified under adequate combustion conditions. It is considered that the deactivation of the upper level CO_2 is reduced because vibration energy level of O_2 (=1556 cm^<-1>) is close to that of H_2O (1595 cm^<-1>). Less

提出了一种串联式能量转换系统，将燃烧产生的高温高压能量转化为三种模式的能量。这些能量模式是激光放大、动能和热能。在本研究中，提取了建立三模能量转换系统所需的条件，并对热激光放大进行了初步的研究。制度中的问题集中在两点上。由于在激光装置后面安装了燃气轮机，由CO_2布居反转引起的红外激光的燃烧温度和放大压力的要求与一般气体动力学激光器的条件完全不同。二是反转过程中CO_2分子的减少。这就是为什么激光介质中H_2O含量的增加会导致激发的CO_2分子失活，尽管CO_2、N_2、H_2O的混合物会在…中产生更多的是碳氢化合物的燃烧反应。对红外激光放大所需的CO_2布居反转识别进行了实验和理论研究。取得的成果如下。气体以超音速快速通过喷嘴，迫使平移温度降至较低的值。结果表明，下能级的振动温度接近平移温度，而上能级的振动温度接近预膨胀温度。利用甲烷在富氧场中燃烧产生的激光介质，实验研究了10.6μm红外光的放大。富氧燃烧是一种容易产生高温高压气体的方法。在适当的燃烧条件下，确定了正收益。认为O_2的振动能级(=1556 cm~(-1))与H_2O(=1595 cm^~(-1)~(-1))的振动能级接近，从而降低了上层CO_2的失活。较少