longitudinal heat conduction is an important parameter in the cryogenic field, especially in cryogenic heat exchangers. in the present work, the parasitic effect of tube wall longitudinal heat conduction on temperature measurement has been studied in cryogenic laminar hydrogen flow. the effects of various parameters such as wall cold end temperature, wall thermal conductivity, gas volumetric fl...

A spatiotemporal study of neutral gas temperature during the first 100 s of operation for a radio-frequency electrothermal plasma micro-thruster operating on nitrogen at 60 W and 1.5 Torr is performed to identify the heating mechanisms involved. Neutral gas temperature is estimated from rovibrational band fitting of the nitrogen second positive system. A set of baffles are used to restrict the ...

Abstract The results of experimental studies direct current electric discharge in the gas-liquid medium an electrolyte with bubbles for various interelectrode distances (l=50-150 mm) inside a dielectric tube are presented. presence bubble structure microdischarges affects nature and voltage ripples. frequency spectrum oscillations was established using fast Fourier transform. Based on analysis ...

The model of a DC glow discharge with metastable argon atoms and dust particles based on the Boltzmann equation for electron energy distribution function (EEDF), particle charging, balance is presented. processes direct stepwise impact ionization, metastable-metastable collisions, recombination electrons ions surface tube wall are taken into account. results show that densities in strong correl...

A 1D corona discharge model coupled to a 2D-axisymmetric particle charging model are proposed in this paper to simulate nanoparticle charging process within a wire-tube air corona discharge subjected to an applied positive or negative dc voltage. This 1D discharge model provides the distribution of the electric field, the air ion and free electron concentrations for the 2D charging model which ...

The chemical dry etching of silicon nitride (Si3N4)and silicon nitride (SiO2) in a downstream plasma reactor using CF4, O2, and N2 has been investigated. A comparison of the Si3N4 and SiO2 etch rates with that of polycrystalline silicon shows that the etch rates of Si3N4 and SiO2 are not limited by the amount of fluorine arriving on the surface only. Adding N2 in small amounts to a CF4 /O2 micr...

We have established a simple method for assaying the quantity of soluble bromine in the discharge tubes of an extra-high-pressure mercury discharge lamp. Each discharge tube is destroyed in 5 ml of 10 mM sodium hydroxide, and the recovered sodium hydroxide solution is analyzed by suppressed-ion chromatography using gradient elution. We have clarified that this method can assay less than 1 micro...

Hydrogen radio frequency (RF) discharge was studied by optical emission spectroscopy and actinometry. The main aim of this work was the comparison of RF discharges at 2 frequencies – 13.56 MHz and 27 MHz as sources of atomic hydrogen. The power delivered to discharge was 30 W. The concentration of atomic hydrogen was determined by actinometric method in the 200 – 600 Pa pressure range with 5% a...

Longitudinal heat conduction is an important parameter in the cryogenic field, especially in cryogenic heat exchangers. In the present work, the parasitic effect of tube wall longitudinal heat conduction on temperature measurement has been studied in cryogenic laminar hydrogen flow. The effects of various parameters such as wall cold end temperature, wall thermal conductivity, gas volumetric fl...