scholarly journals Application of high optical technologies to determine the temperature field, ingredient composition and microstructure of the dispersed phase of combustion products of energy fuels

2020 ◽  
Vol 216 ◽  
pp. 01031
Author(s):  
Nikolay Moskalenko ◽  
Azat Akhmetshin ◽  
Yana Safiullina
Keyword(s):  
Temperature Field ◽  
Power Plants ◽  
Radiation Heat Transfer ◽  
Combustion Products ◽  
Spectral Lines ◽  
High Spectral Resolution ◽  
Dispersed Phase ◽  
Combustion Chambers ◽  
Fixed Temperature ◽  
Ingredient Composition

Application of high optical technologies for determining the temperature field, ingredient composition and microstructure of the dispersed phase of combustion products of power fuels is considered. The temperature of the combustion products is determined by method of the self-reversal of spectral lines. To determine the ingredient composition, the methods of fine-structure spectroscopy are used, when the absorption spectra of flame radiation are measured with a high spectral resolution. Then the ingredients are identified by the position of the spectral lines, and their concentration – by the intensity of the spectral lines at a fixed temperature. The temperature field in the combustion chambers of power plants is reconstructed by the method of numerical simulation of radiation transfer in combustion products of an inhomogeneous radiation propagation medium. The obtained experimental data on optical characteristics are used to solve problems of radiation heat transfer in combustion chambers of power plants with multi-chamber furnaces. Prospects for the creation of high-temperature atlases of the parameters of spectral lines of the ingredients of the gas phase of combustion products and their application in promising developments of power plants and in rocket technology are considered.

scholarly journals Numerical modeling of radiation heat exchange in combustion chambers and heat exchangers of power installations

2020 ◽  
Vol 209 ◽  
pp. 03018
Author(s):  
Nikolay Moskalenko ◽  
Ibragim Dodov ◽  
Azat Akhmetshin
Keyword(s):  
Numerical Modeling ◽  
Heat Exchange ◽  
Radiation Heat Transfer ◽  
Combustion Products ◽  
Spectral Lines ◽  
Spectral Transmission ◽  
Radiation Heat ◽  
Combustion Chambers ◽  
Two Phase ◽  
Radiation Heat Exchange

The application of numerical modeling is considered to solve the problems of radiation heat exchange in structurally inhomogeneous two-phase media which are realized during the combustion of fuel in boiler units atmospheric emissions from air carriers when they move at supersonic speeds. The optically active ingredients of the gas phase of the combustion products have a sharp selection of spectral absorption lines (radiation) which causes a difference in the spectral transmission functions for selective radiation from the spectral transmission functions for non-selective radiation (gray body). In the presence of a dispersed phase of the combustion products acute selection is subjected to such a parameter of the radiation propagation medium as the probability of quantum survival. The number of spectral lines determining the spectral transmission functions increases with temperature and is determined by hundreds of thousands of lines at high temperatures. In this paper we consider a closed simulation of radiation heat transfer in combustion chambers when the temperature field in the combustion chambers is calculated first and then the flux of thermal radiation to the tube heat-receiving surfaces.

scholarly journals MODELATION OF THE RADIATION CHARACTERISTICS OF THE GAS PHASE COMBUSTION PRODUCTS BASED ON HIGH THEMPERATURE ATLASES OF SPECTRAL LINE PARAMETERS

2019 ◽  
Vol 20 (11-12) ◽  
pp. 65-80
Author(s):  
N. I. Moskalenko ◽  
I. R. Dodov ◽  
G. V. Kayumova ◽  
A. R. Khaertdinova ◽  
M. S. Khamidullina ◽  
...  
Keyword(s):  
Gas Phase ◽  
Radiation Heat Transfer ◽  
Experimental Studies ◽  
Direct Calculation ◽  
Combustion Products ◽  
Spectral Lines ◽  
Radiation Heat ◽  
Absorption Bands ◽  
Radiation Characteristics ◽  
Multicomponent Media

High temperature atlass of spectral lines parameters of the combustion production of energy fuels and their use for modeling the radiation characteristics of the optically active ingredients and radiation heat transfer in high structurally inhomogeneous multicomponent media are considering. The model of the absorption bands to determine the functions of spectral transmission and parameterization according to the results of numerical modelation performed by direct calculation of the fine structure of the emission (absorption) spectra, followed by their numerical integration. The results of the calculations are compared with the data of experimental studies.

scholarly journals Measuring complex for examination the combustion products’ composition and the soot particulate sol microstructure

2019 ◽  
Vol 124 ◽  
pp. 05014 ◽  
Author(s):  
N.I. Moskalenko ◽  
I.R. Dodov ◽  
M.S. Khamidullina ◽  
Ya.S. Safiullina
Keyword(s):  
Cross Sections ◽  
Electric Heating ◽  
Combustion Products ◽  
Dispersed Phase ◽  
Resolution Limit ◽  
Measuring Complex ◽  
Asbestos Cement ◽  
Light Filters ◽  
Industrial Energy ◽  
Ingredient Composition

A measuring complex of spectral instrumentation for examination of the ingredient composition, optical characteristics and microstructure of the dispersed phase of the combustion products of energy fuels and atmospheric anthropogenic emissions is discussed. The measuring complex includes a multi-pass cell with external and internal electric heating, which makes it possible to change the temperature of the radiation propagation medium in a multi-pass cell in the temperature range of 300–800 K, in the pressure range of 1*102 ≤ P ≤ 3*106 Pa with optical path L = 2, 4, 6, ... 30 m. Registration of spectra is performed by an upgraded spectrometer IKS-31 with interchangeable sources and radiation receivers, interchangeable diffraction gratings and cut-off light filters, interchangeable quartz windows, CaF2, LiF, MgF2, IKS-25, KRS-5, ensuring their operation in the spectral region of 0.2–100 μm with the spectral resolution limit Δν = 0.2 cm-1. The measuring complex has a complete metrological assurance. The obtained data on the spectral dependences of the effective cross sections for absorption, scattering, and attenuation of radiation are used to restore the microstructure of the dispersed phase of the combustion products. The atmospheric emissions of combustion products of wood, industrial energy, air carriers, decomposition products of asbestos-cement slabs during their calcinations were analyzed.

Direct detection of auroral and equatorial jets in the stratosphere of Jupiter with ALMA

2021 ◽  
Author(s):  
Thibault Cavalié ◽  
Bilal Benmahi ◽  
Vincent Hue ◽  
Raphael Moreno ◽  
Emmanuel Lellouch ◽  
...  
Keyword(s):  
Temperature Field ◽  
Direct Detection ◽  
Auroral Oval ◽  
Auroral Zone ◽  
Spectral Lines ◽  
High Spectral Resolution ◽  
Tropical Region ◽  
Polar Regions ◽  
Zonal Winds ◽  
Doppler Shifts

<p>The upper tropospheric zonal winds have been measured since decades using cloud tracking with maximum winds speeds of ∼ 100 m/s in the tropical region (Ingersoll et al. 1979). Juno measurements have shown that these winds extend in the deep layers of the planet (Kaspi et al. 2018). In the ionosphere, jets have been detected in the auroral zone with velocities of 1-2 km/s (Rego et al. 1999). In-between these atmospheric regions, in the stratosphere, there are no such tracers as clouds. Even if zonal winds can in principle be indirectly derived from temperature field by assuming the thermal wind balance (e.g. Flasar et al. 2004), this technique relies on a boundary condition often taken as the cloud-top structure which is located at levels that are separated from where the stratospheric temperature field is constrained. Also, this technique breaks down at equatorial latitudes.</p><p>Using the Atacama Large Millimeter/submillimeter Array, we mapped Jupiter’s stratospheric HCN emission in March 2017 to directly measure wind-induced Doppler shifts on the spectral lines. We imaged the HCN limb emission with an angular resolution of 1” and a very high spectral resolution. After subtracting the rapid rotation of the planet from the Doppler shifts measured on the spectral lines, we derived the wind speeds as a function of latitude on both limbs.</p><p>We find strong tropical jets at 1 mbar with velocities of 100-200 m/s lying atop the layers where the Quasi-Quadrennial Oscillation occurs. Most surprisingly, we find strong non-zonal winds in Jupiter’s polar regions at 0.1 mbar with counter-rotation velocities of 300-400 m/s. Their position coincides with the location of the main auroral oval.</p><p>In this paper, we will present our observations and results. We will also discuss their implications on the dynamics and chemistry of Jupiter’s stratosphere.</p>

Laser Beam Welding of Open-Porous Metallic Foams for Application in Cooling Structures of Combined Cycle Power Plants

2010 ◽  
Vol 132 (5) ◽  
Author(s):  
Uwe Reisgen ◽  
Simon Olschok ◽  
Stefan Longerich
Keyword(s):  
Laser Beam ◽  
Power Plants ◽  
Laser Beam Welding ◽  
Combined Cycle ◽  
Metallic Foam ◽  
Research Centre ◽  
Combustion Chambers ◽  
Multilayer Systems ◽  
Wall Area ◽  
Graded Structures

Within the Collaborative Research Centre 561, “Thermally highly loaded, porous and cooled multilayer systems for combined cycle power plants,” open-porous and high-temperature stable Ni-based structures are being developed for the requirements of effusion cooling. A two-dimensional cooling strategy for the walls of combustion chambers, which allows the outflow of the cooling medium over the complete wall area of the combustion chamber, could be realized by an open-porous metallic foam structure. The open-porous metallic foam is produced by the “slip reaction foam sintering” process, a powder metallurgical process. To join several foams to assemble structural elements, laser beam welding has been used. Different joining strategies have been examined to find out the most suitable method to join these foams. In this paper, the process setups, settings of the different strategies, and results of trials (seam geometry and strength tests) are discussed. The need for graded structures to combine the essential permeability and adequate weldability is also shown.

scholarly journals ОСОБЕННОСТИ ПРИМЕНЕНИЯ ПРОДУКТОВ КОНВЕРСИИ МЕТАНОЛА В СУДОВОЙ ГАЗОТУРБИННОЙ УСТАНОВКЕ С ТЕРМОХИМИЧЕСКОЙ РЕГЕНЕРАЦИЕЙ СБРОСНОГО ТЕПЛА

2019 ◽  
pp. 28-34 ◽  
Author(s):  
Александр Константинович Чередниченко
Keyword(s):  
Energy Efficiency ◽  
Gas Turbine ◽  
Heat Recovery ◽  
Power Plants ◽  
Low Carbon ◽  
Steam Conversion ◽  
Working Pressure ◽  
Fixed Temperature ◽  
Heat Potential ◽  
Thermochemical Heat Recovery

The research’s subject is the processes of energy transformation of fuel in the ship gas turbine plant with thermochemical regeneration. Modern approaches to assessing the energy efficiency of ship power plants were considered. The characteristics of traditional and alternative marine fuels were analyzed. The use of methanol as a low-carbon marine fuel is discussed. It is proposed to increase the efficiency of methanol use by using synthesis gas obtained through thermochemical heat recovery of secondary energy resources of ship engines. The main objective of the study is to analyze the effects on the energy efficiency of steam thermochemical transformation of methanol of the limitations associated with the system of supplying gaseous fuel to the engine. The influence of pressure in the thermochemical reactor on the steam’s efficiency of reforming of methanol was analyzed. The design schemes of two variants of the ship gas turbine installation with thermochemical heat recovery by steam conversion of methanol are presented. The methanol conversion efficiency was determined by the heat potential of the exhaust gases and was calculated based on the thermal balance of the thermochemical reactor. The reactor’s model is two- component. The mathematical model of the turbocompressor unit is based on an enlarged calculation taking into account the total pressure loss in all elements of the gas-air duct. The results of mathematical modeling of processes in plants based on gas turbine engines of simple and regenerative cycles under conditions of fixed methanol’s consumption, the fixed temperature of the gas in the turbine’s front for environmental parameters according to ISO 19859: 2016 are presented. The efficiency of the scheme which used steam conversion of methanol at pressures corresponding to the working pressure in the combustion chamber was revealed. The increase in the energy efficiency of the installation is 3 ... 5 % with basic parameters and 10 ... 11 % for higher conduction temperatures or for catalytic reactors. The research results can be used in the promising power plants designing.

scholarly journals INFLUENCE OF HEATING OF A GAS-AIR MIXTURE ON THE CHARACTERISTICS OF COMBUSTION OF FUEL GASES

2021 ◽  
pp. 83-90
Author(s):  
Alyona Shilova ◽  
◽  
Nikolay Bachev ◽  
Roman Bulbovich ◽  
◽  
...  
Keyword(s):  
Low Temperature ◽  
Flame Front ◽  
Power Plants ◽  
Combustion Products ◽  
Concentration Limit ◽  
Low Temperature Combustion ◽  
K Value ◽  
Stable Position ◽  
Excess Air ◽  
External Heating

For a stable position of the flame front in the combustion chambers of gas turbine power plants, the fresh gas-air mixture must be heated to the ignition temperature during the entire operation process. With air excess coefficients in the interval between the upper and lower concentration limits, reverse currents from the zone of developed combustion successfully cope with this task. When organizing low-temperature combustion near the lean limit, the contribution of reverse currents to heating the fresh gas-air mixture turns out to be insufficient and additional external heating of the components in special heaters with exhaust gases from the turbine is required. The temperature characteristics of the fresh gas-air mixture at the inlet to the chamber and in the zone of return currents, as well as combustion products in the developed flame zone, were obtained from the solution of the energy balance equations. The modes of low-temperature lean combustion with excess air coefficients exceeding the lower concentration limit α = 2 are considered. The calculations were carried out for two values of the ejection coefficient in the zone of reverse currents K = 0.14 and K = 0.30. A K value of 0.14 was obtained using empirical relationships. The value K = 0.30 was obtained from the condition that during stoichiometric combustion, the gas-air mixture is heated completely by reverse currents. It is shown that with an increase in the excess air ratio to ensure a stable position of the flame front, the role of external heating of components increases.

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