scholarly journals Experimental study of the working process in the combustion chamber of a mobile heat and gas generator

2019 ◽  
Author(s):  
A.V. Novikov ◽  
E.A. Andreev
Keyword(s):  
Combustion Chamber ◽  
Building Materials ◽  
Fuel Mixture ◽  
Combustion Products ◽  
Gas Generator ◽  
Working Process ◽  
Chamber Volume ◽  
Air Jet ◽  
Gas Generators ◽  
Fuel Components

Heat generators producing hot fuel mixture combustion products for further heat treatment of different materials by these products are widely used in various industries. They are used, for example, in the operation of drying plants, disposal of hazardous waste, and production of building materials. Currently, there is a need to create mobile heat and gas generators suitable for transportation and rapid deployment in the field. The purpose of the work carried out in BMSTU was the development of all-metal heat and gas generators for use in drying units. In the course of the development the accumulated experience in working out the combustion chambers of rocket and air-jet engines was realized. Methodology was developed to calculate distribution of key parameters of working process occurring in the combustion chamber of the mobile heat generator on the fuel components of the air–natural gas: optimal scheme of mixing was selected by numerical simulation, the calculated fields of combustion product temperatures and concentrations of fuel components in combustion chamber volume were obtained. To implement practically the working process and to confirm the correctness of the calculations a heat and gas generator was designed and experimentally tested. Comparison of calculated and experimental data showed satisfactory agreement of the results.

Effect of Chemical Hythane Composition on Pressure in Combustion Chamber of Engine

2019 ◽  
pp. 36-42
Author(s):  
A. P. Shaikin ◽  
I. R. Galiev
Keyword(s):  
Natural Gas ◽  
Combustion Chamber ◽  
Power Plants ◽  
Engine Speed ◽  
Combustion Engine ◽  
Fuel Mixture ◽  
Maximum Pressure ◽  
Chamber Volume ◽  
Excess Air ◽  
Scientific Papers

The article analyzes the influence of chemical composition of hythane (a mixture of natural gas with hydrogen) on pressure in an engine combustion chamber. A review of the literature has showed the relevance of using hythane in transport energy industry, and also revealed a number of scientific papers devoted to studying the effect of hythane on environmental and traction-dynamic characteristics of the engine. We have studied a single-cylinder spark-ignited internal combustion engine. In the experiments, the varying factors are: engine speed (600 and 900 min-1), excess air ratio and hydrogen concentration in natural gas which are 29, 47 and 58% (volume).The article shows that at idling engine speed maximum pressure in combustion chamber depends on excess air ratio and proportion hydrogen in the air-fuel mixture – the poorer air-fuel mixture and greater addition of hydrogen is, the more intense pressure increases. The positive effect of hydrogen on pressure is explained by the fact that addition of hydrogen contributes to increase in heat of combustion fuel and rate propagation of the flame. As a result, during combustion, more heat is released, and the fuel itself burns in a smaller volume. Thus, the addition of hydrogen can ensure stable combustion of a lean air-fuel mixture without loss of engine power. Moreover, the article shows that, despite the change in engine speed, addition of hydrogen, excess air ratio, type of fuel (natural gas and gasoline), there is a power-law dependence of the maximum pressure in engine cylinder on combustion chamber volume. Processing and analysis of the results of the foreign and domestic researchers have showed that patterns we discovered are applicable to engines of different designs, operating at different speeds and using different hydrocarbon fuels. The results research presented allow us to reduce the time and material costs when creating new power plants using hythane and meeting modern requirements for power, economy and toxicity.

MULTIFOCAL IGNITION OF COMBUSTION CHAMBER BY SUBCRITICAL STREAMER MICROWAVE DISCHARGE

2020 ◽  
Author(s):  
P. V. Bulat ◽  
◽  
M. P. Bulat ◽  
P. V. Denissenko ◽  
V. V. Upyrev ◽  
...  
Keyword(s):  
Combustion Chamber ◽  
Gas Turbines ◽  
Internal Combustion Engines ◽  
Microwave Discharge ◽  
Fuel Mixture ◽  
Combustion Products ◽  
Combustion Chambers ◽  
Entire Volume ◽  
Gas Pumping ◽  
Pumping Units

The challenges facing engine developers, aimed at improving the technical and operational characteristics, more stringent environmental standards, make the work aimed at increasing the efficiency of ignition, systems highly relevant. Technologies of prechamber, arc ignition, and ignition by corona discharge known to date require significant energy costs. In addition, ignition of a fuel mixture by such systems is local which leads to the limitation in the burning rate, incomplete combustion of fuel, and formation of harmful impurities in combustion products. Volumetric or multipoint ignition may significantly increase the effectiveness of the use of ignition systems. The use of a subcritical streamer microwave discharge, which is a network of thin hot channels propagating in the volume of the combustion chamber, seems promising because it provides virtually instantaneous ignition of the mixture in the entire volume. In this paper, the results of experiments using a subcritical streamer microwave discharge are presented. The possibility of volumetric ignition and a substantial increase in the completeness of fuel combustion is demonstrated. A number of indirect evidences indicate the absence of nitrogen oxides in combustion products. The results can be applied to the development of multivolumetric ignition systems in internal combustion engines, gas pumping units, power gas turbines, low-emission combustion chambers, etc.

scholarly journals ENERGY EFFICIENCY OF BIOMASS GAS GENERATOR STOVES WITH PERIPHERICAL AND CENTRAL GASES BURNING

2020 ◽  
pp. 27-33
Author(s):  
V.P. Klius ◽  
M.M. Zhovmir ◽  
S.V. Klius
Keyword(s):  
Energy Efficiency ◽  
Combustion Chamber ◽  
Combustion Products ◽  
Efficiency Coefficient ◽  
Water Heating ◽  
Wood Pellets ◽  
Gas Generator ◽  
Combustible Gas ◽  
Air Mixing ◽  
Generator Gas

This paper is devoted to research and improvement of biomass gas generator stoves. Experience in outdoors application of the gas generator stoves showed a need to stabilize the burning of the generator gas. In previous works, investigations in operation of the gas generator stoves were carried out analogically to that of gas-fired household stoves in the mode of water heating in pot. Stoves operation in the mode of food cooking, which characterized byy other conditions of heat exchange, was not examined. The purpose of work is to investigate the influence of the organization of generator gas and air reaction with protection against atmospheric impacts on the energy efficiency of the gas generator stove in modes, which consistent with the stove usage for water heating for household needs and food boiling. To stabilize the gas generator stove operation, it was proposed to perform the mixing of generator gas with air and their reaction in the combustion chamber with the release of combustion products through the narrowed central opening. Comparison of two stove modifications was made — the first without combustion chamber, named as stove with peripheral burning, in which burning of combustible gas occurs near the air nozzles evenly spaced on the top of reactor; the second stove modification — with a combustion chamber, named as a stove with central burning, in which the combustible gas is more uniformly blended with the air, and burning occurs at center of the combustion chamber. Such an approach protects the combustion zone from atmospheric influences. The methodology of the research consisted in determining the energy efficiency coefficient of the gas generator stove with wood pellets burning at different approaches to the organization of generator gas and air mixing and reacting, as well as clarification of influence of stove application for water heating and water heating with prolonged boiling on stove’s energy efficiency. Experimentally find out, what stove with combustion chamber having central combustion and protection of flame from atmospheric influences in water heating mode had increased efficiency up to 29.6 % compared to 25.1 % for the stove with peripheral burning. The average useful heat productivity of stoves both with the peripheral and central combustion was near the same 1.2 kW. Application of gas generator stove for water heating with its prolonged boiling (cooking mode) led to a decrease in efficiency, for the stove with central burning efficiency decreased from 29.6 % to 21.9 %. Ref. 9, Fig. 1, Tab. 3.

ANALYSIS OF TECHNOLOGICAL POSSIBILITIES OF TWO-CHAMBER IMPULSE DEVICES FOR SHEET STAMPING

2022 ◽  
pp. 111-117
Author(s):  
А.Ю. Боташев ◽  
А.А. Мусаев
Keyword(s):  
Combustion Chamber ◽  
Fuel Mixture ◽  
Combustion Products ◽  
Small Scale ◽  
Scale Production ◽  
Technological Capabilities ◽  
Combustion Chambers ◽  
Ferrous Alloys ◽  
Stamping Process ◽  
Sheet Stamping

Проведен анализ технологических возможностей двухкамерных устройств для листовой штамповки с одной и двумя камерами сгорания. В устройствах с одной камерой сгорания штамповка детали происходит в холодном состоянии заготовки под действием на нее гибкой среды за счет кинетической энергии поршня, ускоряемого продуктами сгорания газообразной топливной смеси. В устройствах с двумя камерами сгорания процесс штамповки совершается с нагревом заготовки воздействием на нее горячего газа, образованного при сгорании в верхней камере предварительно сжатой топливной смеси. При этом сжатие смеси осуществляется за счет энергии продуктов сгорания, образованных в нижней камере сгорания. Доказано, что устройства с одной камерой сгорания целесообразно использовать для штамповки из пластичных сортов сталей деталей разнообразной формы толщиной до 4 мм и из пластичных цветных сплавов толщиной до 8 мм. Устройства с двумя камерами сгорания целесообразно использовать для штамповки деталей из малопластичных сортов алюминиевых, титановых сплавов и других труднодеформируемых сплавов. Двухкамерные устройства для листовой штамповки обладают широкими технологическими возможностями и могут быть эффективно использованы в мелкосерийных производствах для штамповки деталей различной формы We carried out the analysis of technological capabilities of two-chamber devices for sheet stamping with one and two combustion chambers. In devices with one combustion chamber, the stamping process is carried out in the cold state of the workpiece by the action of an elastic medium on it, using the kinetic energy of the piston accelerated by the combustion products of the gaseous fuel mixture. In devices with two combustion chambers, the stamping process is carried out with the heating of the workpiece by the action of the hot gas formed during combustion in the upper chamber of the pre-compressed fuel mixture. In this case, the mixture is compressed due to the energy of the combustion products formed in the lower chamber. We established that devices with one combustion chamber are expedient to be used for stamping parts of various shapes with a thickness of up to 4 mm and from plastic non-ferrous alloys with a thickness of up to 8 mm from ductile steels. Devices with two combustion chambers are advisable to be used for stamping parts from low-plastic grades of aluminum, titanium alloys and other hard-to-deform alloys. Two-chamber devices for sheet stamping have wide technological capabilities and can be effectively used in small-scale production for stamping parts of various shapes

DEVELOPMENT OF THE COMBUSTION CHAMBER OF GAS ENGINE, CONVERTED ON THE BASIS OF DIESELS D-120 OR D-144 ENGINES TO WORK FOR ON LIQUEFIED PETROLEUM GAS

2019 ◽  
pp. 2-8
Author(s):  
Serhii Kovalov
Keyword(s):  
Combustion Chamber ◽  
Compression Ratio ◽  
Diesel Engines ◽  
Combustion Engine ◽  
Motor Fuel ◽  
Liquefied Petroleum Gas ◽  
Gas Engine ◽  
Chamber Volume ◽  
Motor Fuels ◽  
Dynamic Cycle

The expediency of using vehicles of liquefied petroleum gas as a motor fuel, as com-pared with traditional liquid motor fuels, in particular with diesel fuel, is shown. The advantages of converting diesel engines into gas ICEs with forced ignition with respect to conversion into gas diesel engines are substantiated. The analysis of methods for reducing the compression ratio in diesel engines when converting them into gas ICEs with forced ignition has been carried out. It is shown that for converting diesel engines into gas ICEs with forced ignition, it is advisable to use the Otto thermo-dynamic cycle with a decrease in the geometric degree of compression. The choice is grounded and an open combustion chamber in the form of an inverted axisymmetric “truncated cone” is developed. The proposed shape of the combustion chamber of a gas internal combustion engine for operation in the LPG reduces the geometric compression ratio of D-120 and D-144 diesel engines with an unseparated spherical combustion chamber, which reduces the geometric compression ratio from ε = 16,5 to ε = 9,4. The developed form of the combustion chamber allows the new diesel pistons or diesel pistons which are in operation to be in operation to be refined, instead of making special new gas pistons and to reduce the geometric compression ratio of diesel engines only by increasing the combustion chamber volume in the piston. This method of reducing the geometric degree of compression using conventional lathes is the most technologically advanced and cheap, as well as the least time consuming. Keywords: self-propelled chassis SSh-2540, wheeled tractors, diesel engines D-120 and D-144, gas engine with forced ignition, liquefied petroleum gas (LPG), compression ratio of the internal com-bustion engine, vehicles operating in the LPG.

IMPROVING THE EFFICIENCY OF HOT GAS GENERATORS FOR HEATING AUTOMOTIVE EQUIPMENT

2021 ◽  
Vol 2 (143) ◽  
pp. 46-53
Author(s):  
Andrey V. Negovora ◽  
◽  
Makhmut M. Razyapov ◽  
Arseniy A. Kozeyev
Keyword(s):  
Heat Pipe ◽  
Thermal Energy ◽  
Thermal Power ◽  
Research Purpose ◽  
Gas Generator ◽  
Thermoelectric Converter ◽  
Remote Monitoring System ◽  
Hot Gas ◽  
Safety Research ◽  
Gas Generators

Hot gas generators are used as a source of thermal energy for pre-start preparation of motor vehicles in cold climatic conditions. Their wide application is due to the high thermal power and safety. (Research purpose) The research purpose is in determining the possibilities of using thermoelectric modules to reduce the energy consumption of the battery by hot gas generators. (Materials and methods) Authors used research methods based on the application of standard techniques, while the object of research was the power supply system of a thermal energy source. (Results and discussion) Authors conducted research on ways and methods to reduce the electric consumption of a hot gas generator by recuperating thermal energy into electrical energy using thermoelectric generator modules. The thermoelectric converters installed on the heat pipe of the hot gas generator, due to the high temperature difference, will allow to obtain a high value of the electromotive force. Modeling of the nozzle in the software package of the Ansys three-dimensional modeling system showed that part of the heat energy goes through the surface of the heat pipe. The article proposes the use of a nozzle with a thermoelectric converter installed on the outer surface of the cylinder instead of a heat pipe. The article presents the mathematical model of an improved hot gas generator nozzle. (Conclusions) The use of a thermoelectric converter for the utilization of thermal energy and the replacement of energy losses of the battery, which feeds the hot gas generator, will reduce the internal power losses of the battery and increase the technical readiness of automotive equipment. The introduction of a comprehensive heat treatment system, which is intelligently and functionally linked to a remote monitoring system, will significantly increase the service life of the units most exposed to temperature influences.

STUDYING THE PROCESS OF HEATING OF A PIPE BILLET DURING GAS FORMING

2021 ◽  
pp. 156-161
Author(s):  
А.Ю. Боташев ◽  
Р.А. Байрамуков ◽  
Н.У. Бисилов ◽  
Р.С. Малсугенов
Keyword(s):  
Heat Transfer ◽  
Heat Balance ◽  
Heating Temperature ◽  
Fuel Mixture ◽  
Combustion Products ◽  
New Device ◽  
Combustible Gas ◽  
Ferrous Metals ◽  
Non Ferrous Metals ◽  
Propane Butane

Разработана и представлена схема нового устройства, осуществляющего штамповку деталей с нагревом трубной заготовки воздействием продуктов сгорания газообразной топливной смеси. В качестве топливной смеси может использоваться горючий газ - смесь воздуха с метаном или с пропан-бутаном. Представлены результаты исследования процесса нагрева трубной заготовки воздействием продуктов сгорания. Исследование проведено на базе уравнений конвективного теплообмена, теплового баланса и термодинамики. Получена зависимость для определения температуры нагрева трубной заготовки. Установлено, что температура заготовки зависит от материала и геометрических размеров заготовки, а также давления топливной смеси. Данное устройство обеспечивает нагрев до интервала горячей обработки стальных трубных заготовок диаметром более 150 мм при толщине стенки до 1,2…1,5 мм, а при диаметре более 300 мм - толщиной до 2,0…2,5 мм. Для нагрева трубных заготовок из цветных металлов и сплавов (например, алюминия и меди) требуется меньшее давление топливной смеси, чем для стали, благодаря этому обеспечивается нагрев заготовок значительно большей толщины, в частности, заготовок из алюминия толщиной до 6 мм We developed a diagram of a new device for stamping parts by heating a pipe billet by the action of combustion products of a gaseous fuel mixture. A combustible gas can be used as a fuel mixture - a mixture of air with methane or with propane-butane. We present the results of a study of the process of heating a pipe billet by the action of combustion products. We carried out the study on the basis of the equations of convective heat transfer, heat balance and thermodynamics. We obtained the dependence for determining the heating temperature of the pipe billet. We found that the temperature of the workpiece depends on the material and geometric dimensions of the workpiece, as well as the pressure of the fuel mixture. This device provides heating to the hot working interval of steel pipe billets with a diameter of more than 150 mm with a wall thickness of up to 1.2 ... 1.5 mm, and with a diameter of more than 300 mm - with a thickness of up to 2.0 ... 2.5 mm. To heat tubular billets made of non-ferrous metals and alloys (for example, aluminum and copper), a lower pressure of the fuel mixture is required than for steel, due to this, billets of a much greater thickness are heated, in particular, billets made of aluminum with a thickness of up to 6 mm

Local Heat Exchange in the Combustion Chamber of a Hydrogen Engine Running on a Lean Fuel Mixture

2021 ◽  
Vol 50 (1) ◽  
pp. 79-87
Author(s):  
R. Z. Kavtaradze ◽  
A. M. Kondratev ◽  
Ch. Rongrong ◽  
Ch. Citian ◽  
S. Baigang ◽  
...  
Keyword(s):  
Heat Exchange ◽  
Combustion Chamber ◽  
Fuel Mixture ◽  
Local Heat ◽  
Lean Fuel

Numerical Investigation of the Influence of Flow Parameters Nonuniformity at the Diffuser Inlet on Characteristics of the GTE Annular Combustion Chamber

2015 ◽  
Author(s):  
Sergey S. Matveev ◽  
Ivan A. Zubrilin ◽  
Mikhail Yu. Orlov ◽  
Sergey G. Matveev
Keyword(s):  
Combustion Chamber ◽  
Dynamic Pressure ◽  
Air Distribution ◽  
Gas Generator ◽  
Air Velocity ◽  
Degree Polynomial ◽  
Flow Dynamic ◽  
Ansys Fluent ◽  
Flow Parameters ◽  
Mode Of Operation

Parameters at a combustion chamber’s inlet significantly vary in an aircraft engine’s transient states of operation. At the same time, there is a significant spatial heterogeneity of flow parameters at a diffuser inlet of a combustion chamber, which is defined by nature of flow in a compressor and an individual for each mode of operation of a specific gas generator. In this paper presented a study of an influence of radial and circumferential nonuniformities of flow parameters on characteristics of a combustion chamber. Multi spray for annular combustion chamber with two rows of burner is considered. Z-shaped sector, which contains two nozzles of outer and two nozzles of inner row, was selected as the calculated domain. Calculations were carried out in ANSYS Fluent 14.5 software package with an implementation of cluster analysis. Nonuniformity at a diffuser inlet was set as fifth degree polynomial, which was derived from a numerical simulation of a compressor. As a result it was established, that radial nonuniformity of flow parameters at an inlet of a combustion chamber influences on characteristics of a combustion chamber. A stretched shape of velocity profile contributes to higher air flow dynamic pressure on dome than using uniform profile air velocity. At that, local equivalents ratio excess are changing, and consequently, sizes and location NOx production zones are changing as well. The residual rotation of flow from the compressor leads to a lesser effect on total pressure drop and air distribution in flame tube. The obtained results showed that, during a design of a combustion chamber, it is necessary to take into account nonuniformity of parameters’ distribution at its inlet.

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