Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic acc...Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic accelerometer, where the test mass is suspended by a fiber to compensate for its weight, and this scheme demonstrates an advantage, compared with the high-voltage levitation scheme, in which the effect of the seismic noise can be suppressed for a few orders of magnitude in low frequencies. In this work, the capacitive electrode cage is proposed to be suspended by another pendulum, and theoretical analysis shows that the effects of the seismic noise can be further suppressed for more than one order by suspending the electrode cage.展开更多
This paper is a final report of the experimental investigation of the cavitation noise.In the paper is described the basic characteristics of the cavitation noise and the significant experiment results for the similar...This paper is a final report of the experimental investigation of the cavitation noise.In the paper is described the basic characteristics of the cavitation noise and the significant experiment results for the similarity the limiting value and the control of the cavitation noise展开更多
After about 10 years' runing of the LCC (DTRC, USA) and the HYKAT( HSVA,Germany) , another new large cavitation channel with low background noise is to be in operation inChina Ship Scientific Research Center(CSS-R...After about 10 years' runing of the LCC (DTRC, USA) and the HYKAT( HSVA,Germany) , another new large cavitation channel with low background noise is to be in operation inChina Ship Scientific Research Center(CSS-RC), Wuxi, China. The important specific properties of thechannel are the large test section (2. 0 m in height, 2. 2 m in width and 10. 5 m in length) , themaximum speed of more than 15 m/s, the low turbulence level, the low background noise of the wholefacility, together with the new noise measurement system. So large scale models can be tested withonly minor wall effects and at high Renolds numbers, and the pretentious acoustical measurements canbe performed. This paper describes the features of the new channel and the first test resultsobtained during extensive calibration and validation.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11235004
文摘Performance test of a high precise accelerometer or an inertial sensor on the ground is inevitably limited by the seismic noise. A torsion pendulum has been used to investigate the performances of an electrostatic accelerometer, where the test mass is suspended by a fiber to compensate for its weight, and this scheme demonstrates an advantage, compared with the high-voltage levitation scheme, in which the effect of the seismic noise can be suppressed for a few orders of magnitude in low frequencies. In this work, the capacitive electrode cage is proposed to be suspended by another pendulum, and theoretical analysis shows that the effects of the seismic noise can be further suppressed for more than one order by suspending the electrode cage.
文摘This paper is a final report of the experimental investigation of the cavitation noise.In the paper is described the basic characteristics of the cavitation noise and the significant experiment results for the similarity the limiting value and the control of the cavitation noise
文摘After about 10 years' runing of the LCC (DTRC, USA) and the HYKAT( HSVA,Germany) , another new large cavitation channel with low background noise is to be in operation inChina Ship Scientific Research Center(CSS-RC), Wuxi, China. The important specific properties of thechannel are the large test section (2. 0 m in height, 2. 2 m in width and 10. 5 m in length) , themaximum speed of more than 15 m/s, the low turbulence level, the low background noise of the wholefacility, together with the new noise measurement system. So large scale models can be tested withonly minor wall effects and at high Renolds numbers, and the pretentious acoustical measurements canbe performed. This paper describes the features of the new channel and the first test resultsobtained during extensive calibration and validation.
