Formation of detonation in a pulse combustion chamber with a porous obstacle

2012 ◽  
Vol 85 (5) ◽  
pp. 1052-1057
Author(s):  
Kh. Alhussan ◽  
M. S. Assad ◽  
O. G. Penyazkov ◽  
K. L. Sevruk
Keyword(s):  
Combustion Chamber ◽  
Pulse Combustion ◽  
Porous Obstacle

Performance and Operating Characteristics of Micro Gas Turbine Driven by Pulse, Pressure Gain Combustor

2020 ◽  
Author(s):  
Takashi Sakurai ◽  
Shunsuke Nakamura
Keyword(s):  
Combustion Chamber ◽  
Gas Turbine ◽  
Pulse Pressure ◽  
Constant Pressure ◽  
Engine Performance ◽  
Combustion Mode ◽  
Operating Characteristics ◽  
Combustion Chambers ◽  
Micro Gas Turbine ◽  
Pulse Combustion

Abstract This paper presents the experimental results of a micro gas turbine driven by pulse, pressure gain combustor. The aim of this study is to demonstrate the improvement of the engine performance by applying the pressure gain combustion. The micro gas turbine is composed of a combustor having two combustion chambers and an automotive turbocharger which is used as a compressor and a turbine. The outlets of two combustion chambers are joined by a confluence part to connect with the turbine. By changing the combustion methods of each combustion chamber, the gas turbine was operated in three modes; normal combustion mode, pulse combustion augmented mode, and fully pulse combustion mode. In the normal combustion mode, two combustion chambers were operated under continuous, constant-pressure combustion. In the pulse combustion augmented mode, one combustion chamber was operated under continuous, constant-pressure combustion and the other was operated under pulse combustion. In the fully pulse combustion mode, two combustion chambers were operated under pulse combustion. The pulse combustion applied in this study was the forced-ignition type, active pulse combustion. Although the pressure increase was attained by the pulse combustion comparing with the normal combustion, the mass-averaged pressure in the combustor showed that the net pressure gain in the combustor was not attained. The engine performance such as thermal efficiency and work and operating characteristics of gas turbine were investigated for two operation modes. In the pulse combustion augmented mode, the gas turbine could successfully sustain its operation as well as normal operation mode. The increase in the combustor pressure affected the air mass flow rate and the compressor performance, resulted in the decrease of performance comparing with the normal combustion mode.

Combustion Characteristics of a Helmholtz-Type Valveless Self-Excited Pulse Combustor

2013 ◽  
Vol 291-294 ◽  
pp. 1719-1722 ◽  
Author(s):  
Yu Fen Qian ◽  
Yan Ying Xu ◽  
Ti Hai Xu
Keyword(s):  
Combustion Chamber ◽  
Combustion Process ◽  
Acoustic Oscillation ◽  
Combustion Characteristics ◽  
Ignition Source ◽  
Pulse Combustor ◽  
Temperature Combustion ◽  
Pulse Combustion ◽  
Physical And Mathematical Models ◽  
High Temperature Combustion

Combustion characteristics of a Helmholtz-type valveless self-excited pulse combustor with continuous supply of gas and air were studied. The physical and mathematical models are established based on the actual pulse combustor, and the combustion characteristics are simulated with CFD. The results show that the possible re-ignition sources for the pulse combustion may be three. The first source may be the hot remnant gas near gas/air mixture. The second re-ignition source may be the high-temperature combustion chamber wall. The third ignition source is the unburned mixture. The pressure, temperature and mass fraction of propane in the combustion chamber have the phase relations and the combustion process stimulates the acoustic oscillation.

scholarly journals Improvements in the turbo-engine by replacement of conventional combustion chamber by a pulse combustion chamber

2013 ◽  
Vol 60 (4) ◽  
pp. 481-494
Author(s):  
Damian Łapinski ◽  
Janusz Piechna
Keyword(s):  
Combustion Chamber ◽  
Analytical Model ◽  
Combustion Process ◽  
Constant Volume ◽  
Wave Rotor ◽  
Additional Energy ◽  
Pulse Combustor ◽  
Calculation Results ◽  
Pulse Combustion ◽  
Turbo Engine

Abstract This paper comprises description of the turbo engine and evaluation of its analytical model. The analytical model was created to establish a benchmark for further evaluation of a wave rotor combustor (at constant volume). The wave rotor combustor concept was presented and discussed. Advantages of combustion at constant volume were described as well as the basic turbo engine updates required to reflect pulse combustor application. The calculation results for analytical model of a basic engine, and that equipped with pulse combustor are included in this paper. The paper describes the required changes in the engine structure and construction and the estimated thermodynamic improvements. Axial-type pulse multi-chamber combustion unit increasing the pressure and temperature of gases requires a special additional turbine utilizing additional energy and forming the interface between the standard compressor-turbine unit. Performance calculations done for an existing GTD-350 engine showed that constant-volume combustion process is valuable

DETERMINATION OF THE TYPE OF A SINGLE-USE GRENADE LAUNCHER BASED ON ITS COMPOSITE PARTS AND FRAGMENTS OF REACTIVE GRENADE FOUND AT THE PLACE OF ACCIDENT

2017 ◽  
Vol 17 ◽  
pp. 245-252
Author(s):  
V. V. Somov
Keyword(s):  
Combustion Chamber ◽  
Structural Features ◽  
Outlet Section ◽  
Technical Expertise ◽  
Jet Engine ◽  
Size Ofthe ◽  
Single Use ◽  
Nozzle Block ◽  
Considerable Damage

In carrying out an investigation into the explosion, among others, the investigative version of the use of a single-use reactive grenade launcher is being considered. The most common for criminal explosions are applied grenade launchers RPG-18, RPG-22, RPG-26. Their use is due to a number of such properties as small size and weight, which makes it possible to transfer them covertly, the range of the shot significantly exceeding the range of the hand grenade throw, the high detonating effect of the rocket grenade explosion. The single-use rocket launchers are generally of the same design. Their differences are in the features of the components construction and dimensional characteristics, which are given in the article. On the basis of expert practice, details ofgrenade launchers that remain at the site of the explosion and have the least damage are determined. These details are the objects of investigation of the explosion technical expertise. These objects include launchers of grenade launchers and rocket parts ofjet grenades. The design features of the launchers, their dimensional characteristics and marking symbols make it possible to determine their belonging to a specific type of jet grenade launchers. Missile parts of jet grenades differ in the form of the combustion chamber of the jet engine, nozzle, in the size ofthe outlet section of the nozzle, in the form and size of the stabilizerfeathers. To determine the belonging of the rocket part of the grenade to a specific type ofjet grenade launcher, it’s necessary to establish a set of structural features and dimensional characteristics. At considerable damage of the combustion chamber of the jet engine, as a rule, the nozzle block remains intact that allows to define diameter of critical section of a nozzle, and on it to establish type of the used single-use grenade launcher.

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.

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.

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