Acquisition of Time Parameters and Charges in the Streamer Discharge Simulation

2014 ◽  
Vol 986-987 ◽  
pp. 1906-1909
Author(s):  
Ze Zhang ◽  
Yu Jian Ding ◽  
Qing Xie
Keyword(s):  
Dynamic Characteristics ◽  
Air Gap ◽  
New Method ◽  
Discharge Process ◽  
Test Results ◽  
Streamer Discharge ◽  
Stream Discharge ◽  
Discharge Simulation ◽  
Time Parameters

Because of the dynamic characteristics of the streamer discharge, the acquisition of time parameters is very important to the streamer discharge simulation in the rod-plate air gap. This paper raises a new method to get the time parameters and charge development in the discharge of air gas, and the comparison of our results and the test results shows that the new method is very suitable and correctly to describe the stream discharge process.

The development characteristics of the discontinuous leader under the positive switching impulse with low rate of voltage rising

2018 ◽  
Vol 83 (2) ◽  
pp. 20802 ◽  
Author(s):  
Yaoheng Xie ◽  
Yue Yishi ◽  
Huisheng Ye ◽  
Liu Yun ◽  
Yongheng Zhong ◽  
...  
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Unit Length ◽  
Leader Development ◽  
Air Gap ◽  
Discharge Process ◽  
Temperature Changes ◽  
Channel Temperature ◽  
Impulse Voltage ◽  
Low Rate

Discontinuous leader development is the most important discharge process under the application of the switching impulse voltage with the low rate of voltage rising, which is of great significance to study the external insulation characteristics of ultra-high voltage (UHV) large scale air gap. Based on the CMOS high-speed camera, a discharge test with different operating impulse voltage is carried out by constructing a comprehensive observation platform of rod-plate air gap discharge, and a clear discontinuous leader development process picture is captured. Moreover, the leader current, injection charge and leader channel unit length charge, and their characteristics of the change trend are also obtained. Further analysis based on the experimental results shows that the discontinuous leader development under the action of the impulse voltage with low rate of voltage rising has two different laws. Finally, this paper uses the thermodynamic equation, combined with the test results, the channel temperature changes in the discontinuous leader development stagnation stage were calculated. The results show that the leader channel temperature is still greater than 1500 K in the hundreds of microsecond time scales in the leader stagnation stage, and the subsequent leader can continue to develop on the original leader channel.

New Method for Measuring Liquid Level in WFGD System

2011 ◽  
Vol 418-420 ◽  
pp. 1804-1807
Author(s):  
Li Li ◽  
Zheng Hui Tan ◽  
Jia Wen Liu
Keyword(s):  
Flue Gas ◽  
Traditional Method ◽  
Large Deviation ◽  
Flue Gas Desulfurization ◽  
New Method ◽  
Liquid Level ◽  
Test Results ◽  
Economic Operation ◽  
Local Test ◽  
Operation Cost

Traditional method for measuring liquid level of absorption tower in wet flue gas desulfurization (WFGD) system is introduced in this paper, and it's found that measuring accuracy of the method exists in large deviation. A new method is proposed to measure liquid level of absorption tower for this situation. The local test results show that not only measurement result of new method is more close to the actual liquid level than traditional method, but also using new method can save operation cost and ensure the safety, stability, and economic operation of WFGD system.

A New Method to Measure Prandtl Number and Thermal Conductivity of Fluids

1957 ◽  
Vol 24 (1) ◽  
pp. 25-28
Author(s):  
E. R. G. Eckert ◽  
T. F. Irvine
Keyword(s):  
Thermal Conductivity ◽  
Boundary Layer ◽  
Prandtl Number ◽  
High Velocity ◽  
Atmospheric Pressure ◽  
New Method ◽  
Test Results ◽  
Test Setup ◽  
Velocity Boundary Layer ◽  
Layer Flow

Abstract A new method is described by which the Prandtl number and indirectly the thermal conductivity of fluids can be measured. The method is based on the fact that a well-established, unique relation exists between the Prandtl number and the recovery factor for laminar high-velocity boundary-layer flow. The test setup is described which has been devised for such measurements, and test results are presented for air at atmospheric pressure and temperatures between 60 and 350 F.

scholarly journals Examination of combined ferry on the dynamic work

2019 ◽  
Vol 265 ◽  
pp. 02008
Author(s):  
Dmitry Tryapkin ◽  
Yuriy Tryapitsin
Keyword(s):  
Dynamic Characteristics ◽  
Dynamic Coefficient ◽  
Test Results ◽  
Dynamic Work ◽  
Calculation Results

The results of the dynamic characteristics experiments and calculation of combined crossing dynamic coefficient are given. The experiments were carried out by temporal automobile load with using measuring rated complex. Agreement of calculation results and test results is obtained.

Study on Dynamic Characteristics of the Hippocampal Neuron under Current Conductance's Changing

2012 ◽  
Vol 195-196 ◽  
pp. 868-873 ◽  
Author(s):  
Yue Ping Peng ◽  
Nan Zou ◽  
Hai Ying Wu
Keyword(s):  
Dynamic Characteristics ◽  
Formation Process ◽  
Hippocampal Neuron ◽  
Neuron Model ◽  
Discharge Process ◽  
Straight Line ◽  
Hippocampal Ca1 ◽  
Discharge Patterns ◽  
Neural Diseases ◽  
Maximum Conductance

The hippocampal CA1 pyramid neuron has plenty of discharge actions. In the thesis, the dynamic characteristics of the hippocampal neuron model are analyzed and discussed by the neurodynamic theory and methods. Under a certain amplitude currents stimulation, the change of (the maximum conductance of the transient sodium channel) and (the maximum conductance of the delay rectification potassium channel) can cause different dynamic characteristics of the neuron model. The transient Na+current () caused by is indispensable in the discharges formation process of the model. The model can generate the discharge process only when reaches a certain threshold. In the discharge process of the neuron model,s changing affects little and the ISIs approximate to a straight line. The delay rectification K+current () caused by isnt indispensable in the discharges formation process of the model. Buts changing affects much in the discharge process of the neuron model. Withs changing, the neuron model undergoes different dynamic bifurcation process, and has plenty of discharge patterns such as the chaos, period, and so on. This investigation is helpful to know and investigate deeply the dynamic characteristics and the bifurcation mechanism of the hippocampal neuron; and it provides a certain theory assist to investigate the neural diseases such as the Alzheimer disease by neurodynamics.

Characteristics of Films on the Surface of Sea Sand and Effects on the Dissolution of Chloride

2020 ◽  
Vol 842 ◽  
pp. 326-336
Author(s):  
Fei Long Sun ◽  
Shuai Wu ◽  
Quan Jiang ◽  
Huo Cheng Chen ◽  
Hong Yan Guan
Keyword(s):  
Chloride Content ◽  
Water Soluble ◽  
Hot Water ◽  
Water Extraction ◽  
New Method ◽  
Emission Spectrometry ◽  
Specimen Preparation ◽  
Test Results ◽  
Hot Water Extraction ◽  
Sea Sand

In this study, the effects of the specimen preparation method, temperature, and duration of the extraction step for the determination of the water-soluble chloride content of sea sand were investigated. The results demonstrated that increasing the heating temperature and duration promoted the dissolution of chloride, where the maximum value was obtained at 80°C and 60 min. Hot water extraction (80°C/60 min) could eliminate the effects of different specimen preparation methods on the final test results. Therefore, a new method was developed with drying at a temperature of 110 ± 5°C and hot water extraction at a temperature of 80°C for 60 min. The suitability of the new method for determining the water-soluble chloride content of sea sand was verified by testing the extracted specimens again. The results indicated that the chloride in sea sand dissolved fully with the new method, and thus it is suitable for testing the water-soluble chloride content of sea sand. Finally, the organic and inorganic compositions of the film adsorbed on the surface of sea sand were studied based on thermogravimetric analysis, inductively coupled plasma atomic emission spectrometry, ion chromatography, and total organic carbon measurements. The results indicated that a layer of substance (a multi-substance film) was adsorbed onto the surface of sea sand. This layer comprised inorganic salts (such as Cl–, Na+, Mg2+, SO42–, and Ca2+) and organic compounds, which were related to the composition of sea water. The multi-substance film greatly affected the dissolution and diffusion of chloride in the sea sand. Hot water extraction accelerated the dissolution of the film and increased the test results in terms of the water-soluble chloride contents.

Development of a snow-fraction meter based on the conductometric method

1993 ◽  
Vol 18 ◽  
pp. 60-64 ◽  
Author(s):  
Takuo Kitahara ◽  
Masataka Shirakashi ◽  
Yasuhiro Kajio
Keyword(s):  
New Technology ◽  
New Method ◽  
Pipeline System ◽  
Water Mixture ◽  
Test Results ◽  
Practical Application ◽  
Conductometric Method ◽  
Snow Properties ◽  
Snow Water

Hydraulic conveying of snow is one of the most promising techniques for snow removal from an urban area. The method for measuring the fraction of snow in a snow-water mixture flowing in a pipe is a key technique for its practical application. A new method based on the conductometric method has been developed in this study. The method was tested using a prototype snow-fraction meter in a testing apparatus and a closed pipeline system. This type of meter has the advantage of in situ measurement of a wide fraction range from zero up to packed value. The meter is capable of quick response, independent of flow velocity or snow properties and nonintrustive in flow. This paper describes the application of techniques for the development of the meter and the test results. This new method is expected to be useful for hydraulic conveying of ice particles or ice cubes, a new technology in the air-conditioning field.

scholarly journals Concept Map Technique as a New Method for Whole Text Translation

2017 ◽  
Vol 10 (4) ◽  
pp. 62
Author(s):  
Tamara Mohd Altabieri Krishan
Keyword(s):  
Traditional Method ◽  
English Language ◽  
Concept Map ◽  
Arabic Language ◽  
T Test ◽  
New Method ◽  
Test Results ◽  
Test Of Homogeneity ◽  
The Difference

This study discusses the use of concept map tool as a new method for teaching translation (from English language to Arabic language). This study comprised 80 students divided into two groups. The first group was taught the new vocabulary by using the concept tool method, whereas the second group was taught the new vocabulary by the traditional method. Pre-test and test of homogeneity was administered in order to ensure the equivalence of the students. During the training, the two groups were subjected to evaluation tests (first, second and final) in which the students were asked to summarize text into a paragraph by translation. The differences between the two methods were compared by using t-test. Results of pre-test indicated that the difference between the two groups was not significant and the scores were linearly distributed. Results of students’ scores between the two groups for the first exam was not significant, however, the difference between the two groups for second, final and total scores was significant. It was seen that the introduced method of text translation improves the student skills compared with the traditional method.

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