A second harmonic generation system with two type II KDP crystals in quadrature is optimized for the nanosecond chirp pulse. The acceptance bandwidth of this optimizing scheme is close to 10 nm by using two crystals w...A second harmonic generation system with two type II KDP crystals in quadrature is optimized for the nanosecond chirp pulse. The acceptance bandwidth of this optimizing scheme is close to 10 nm by using two crystals with slightly opposite angular detuning from phase matching and the conversion efficiency can reach 70% for top-hat chirp pulse at -2 GW/cm^2 in theory. The preliminary experimental results are obtained on the 9th beam of Shen Guang Ⅱ SGⅡ laser system, and the performance of optimization is partially verified.展开更多
A floating type pendulum wave energy converter(FPWEC) with a rotary vane pump as the power take-off system was proposed by Watabe et al.in 1998.They showed that this device had high energy conversion efficiency.In the...A floating type pendulum wave energy converter(FPWEC) with a rotary vane pump as the power take-off system was proposed by Watabe et al.in 1998.They showed that this device had high energy conversion efficiency.In the previous research,the authors conducted 2D wave tank tests in regular waves to evaluate the generating efficiency of FPWEC with a power take-off system composed of pulleys,belts and a generator.As a result,the influence of the electrical load on the generating efficiency was shown.Continuously,the load characteristics of FPWEC are pursued experimentally by using the servo motors to change the damping coefficient in this paper.In a later part of this paper,the motions of the model with the servo motors are compared with that of the case with the same power take-off system as the previous research.From the above experiment,it may be concluded that the maximum primary conversion efficiency is achieved as high as 98%at the optimal load.展开更多
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China under Grant No.1229241A00
文摘A second harmonic generation system with two type II KDP crystals in quadrature is optimized for the nanosecond chirp pulse. The acceptance bandwidth of this optimizing scheme is close to 10 nm by using two crystals with slightly opposite angular detuning from phase matching and the conversion efficiency can reach 70% for top-hat chirp pulse at -2 GW/cm^2 in theory. The preliminary experimental results are obtained on the 9th beam of Shen Guang Ⅱ SGⅡ laser system, and the performance of optimization is partially verified.
文摘A floating type pendulum wave energy converter(FPWEC) with a rotary vane pump as the power take-off system was proposed by Watabe et al.in 1998.They showed that this device had high energy conversion efficiency.In the previous research,the authors conducted 2D wave tank tests in regular waves to evaluate the generating efficiency of FPWEC with a power take-off system composed of pulleys,belts and a generator.As a result,the influence of the electrical load on the generating efficiency was shown.Continuously,the load characteristics of FPWEC are pursued experimentally by using the servo motors to change the damping coefficient in this paper.In a later part of this paper,the motions of the model with the servo motors are compared with that of the case with the same power take-off system as the previous research.From the above experiment,it may be concluded that the maximum primary conversion efficiency is achieved as high as 98%at the optimal load.