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1

Experimental study of fuel combustion and emission characteristics of marine diesel engines using advanced fuels

Changxiong Li, Hu Yihuai, Yang Zy, Guo Hao

Polish Maritime Research

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2023

|

nr 3

48--58

EN

In order to explore the potential application of oxygenated fuels, polyoxymethylene dimethyl ethers (PODE), as an alternative fuel for marine diesel engines, the fuel combustion performance and gas emission characteristics of pure diesel oil, diesel-blended PODE, and pure PODE were tested on a marine diesel engine under different running conditions. The experimental results indicate that oxygen consumption can be reduced by diesel-blended PODE and pure PODE. The in-cylinder pressure and exothermic curve were consistent with the trend of diesel oil. Also, the ignition delay of diesel-blended PODE and pure PODE decreased, and the diffusion rate was accelerated, which helped to improve the combustion performance of diesel engines. Diesel blended PODE and pure PODE reduced the particulate matter (PM) emissions by up to 56.9% and 86.8%, respectively, and CO emissions by up to 51.1% and 56.3%, respectively. NOx emissions were gradually decreased with engine load. CO2 emissions were slightly increased, and the effective fuel consumption was increased up to 48% and 132%, respectively. It was shown that PODE could provide comparable power in a marine diesel engine and improve the fuel combustion and gas emission of the engine as a clean alternative fuel for marine diesel engines.

2

Effect of Coated Ammonium Dinitramide on the Properties of Nitrate-ester Plasticized Polyether Solid Rocket Propellants

Pang W. Q., Li J. Q., DeLuca L. T., Ke W., Fu X. L., Zhong F. X., Li H., Ji Y. P.

Central European Journal of Energetic Materials

|

2018

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Vol. 15, no. 4

590--609

EN

Several industrial and research types of nitrate-ester plasticized polyether (NEPE) solid propellants were experimentally analyzed. In general, their compositions differed in the mass fraction of ammonium dinitramide (ADN), which was used as a promising highly energetic filler, as an alternative to ammonium perchlorate (AP). ADN exhibits high performance, low signature and non-polluting characteristics. The propellant composition without ADN, but with AP, was used as the reference. The microstructure and granularity distribution of the uncoated and coated ADN particles were experimentally analyzed. It was found that uncoated ADN particles exhibited irregular shape, while the ADN particles after coating are spherical. Because of their irregular shape, uncoated ADN particles caused inferior processability of the propellant slurry when added to the propellant formulation. Consequently, the NEPE propellants with coated ADN were studied in further detail. The rheological properties, energetic properties, mechanical sensitivities and combustion properties (burning rate and pressure exponent) of the NEPE propellants with coated ADN were studied and compared with the reference NEPE propellant. The addition of ADN particles to the propellant formulations increased the standard theoretical specific impulse and heat of explosion of the propellants, while decreasing the density. The propellants containing ADN particles were much more sensitive to impact and friction compared to the reference sample. Moreover, increasing the ADN mass fraction in the propellant formulation can significantly affect the combustion behaviour and increase the burning rate and pressure exponent compared to of the reference formulation. However it appears that ADN is a very promising candidate as a new energetic material in compositions of NEPE propellants, although several important questions concerning ADN’s suitability, especially in the context of its sensitivity to friction and impact, remain to be answered.

3

The research of characteristics of combusting high-energy solid fuels and their fracturing ability to carbon cylinders

Hebda K., Habera Ł., Frodyma A., Wilk Z., Koślik P., Hadzik J.

Materiały Wysokoenergetyczne

|

2017

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T. 9

188--193

EN

The paper presents research results of combusting high-energy solid fuels (propellants) in laboratory rocket motor specifically modified to examine the rocks . The process of combusting highenergy fuel is characterized by fast chemical reaction, which causes creation of high pressure gaseous products. The rate of pressure rise from combusting propellants can be controlled in laboratory rocket motor by an appropriate selection of mass of the fuel and the diameter of the nozzle. By selecting fuel which has bigger mass we can obtain higher rate of pressure rise as compared to smaller mass of fuel. For testing purposes the nozzle from standard laboratory rocket motor was replaced by solid coal cylinder to determine the possibility of coal fracturing by gaseous products of propellant combustion. With the use of sensors there was registered a pressure inside the combustion chamber. The aim of the paper is presentation and comparison of the pressure change graphs which were created in result of combusting high-energy materials and macroscopic determination of carbon fracturing as a result of propellant interaction.

PL

Artykuł przedstawia wyniki badań ze spalania wysokoenergetycznych paliw (propelantów) w specjalnie zmodyfikowanym silniku rakietowym do badań skał. Proces spalania paliw wysokoenergetycznych jest to szybka reakcja chemiczna, w wyniku której powstają produkty gazowe pod wysokim ciśnieniem. Wzrost ciśnienia powstałego w wyniku spalania propelantów można kontrolować w laboratoryjnym silniku rakietowym poprzez właściwy dobór masy paliwa oraz średnicy dyszy. Wybierając paliwo o większej masie można się spodziewać większego wzrostu ciśnienia w porównaniu do ciśnienia wytworzonego z mniejszą ilością propelantu. Na potrzeby badania dysza ze standardowego laboratoryjnego silnika rakietowego została zastąpiona walcem węglowym, aby określić możliwość zeszczelinowania węgla przez gazowe produkty spalania propelantu. Za pomocą czujnika rejestrowane było ciśnienie wewnątrz komory spalania. Celem artykułu jest (1) prezentacja oraz porównanie wykresów zmiany ciśnienia w czasie, które zostały zarejestrowane podczas spalania paliw wysokoenergetycznych (2) określenia makroskopowo zeszczelinowania węgla w wyniku oddziaływania propelantów.

4

CFD modeling of syngas combustion and emissions for marine gas turbine applications

Ammar N. R., Farag A. I.

Polish Maritime Research

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2016

|

nr 3

39--49

EN

Strong restrictions on emissions from marine power plants will probably be adopted in the near future. One of the measures which can be considered to reduce exhaust gases emissions is the use of alternative fuels. Synthesis gases are considered competitive renewable gaseous fuels which can be used in marine gas turbines for both propulsion and electric power generation on ships. The paper analyses combustion and emission characteristics of syngas fuel in marine gas turbines. Syngas fuel is burned in a gas turbine can combustor. The gas turbine can combustor with swirl is designed to burn the fuel efficiently and reduce the emissions. The analysis is performed numerically using the computational fluid dynamics code ANSYS FLUENT. Different operating conditions are considered within the numerical runs. The obtained numerical results are compared with experimental data and satisfactory agreement is obtained. The effect of syngas fuel composition and the swirl number values on temperature contours, and exhaust gas species concentrations are presented in this paper. The results show an increase of peak flame temperature for the syngas compared to natural gas fuel combustion at the same operating conditions while the NO emission becomes lower. In addition, lower CO2 emissions and increased CO emissions at the combustor exit are obtained for the syngas, compared to the natural gas fuel.

5

Wzbogacanie utleniacza w tlen – analiza przypadku silnika ZI

Król Marcin

Archiwum Instytutu Techniki Cieplnej

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2016

|

Vol. 2

59--85

PL

W ostatnich latach obserwowany jest dynamiczny rozwój tzw. energetyki odnawialnej w tym energetyki wiatrowej. Cechą charakterystyczną tej formy energii jest niestabilność oraz mała przewidywalność warunków pogodowych. Powoduje to intensyfikację prac nad sposobami magazynowania energii. Jedną z możliwości jest produkcja wodoru poprzez elektrolizę wody. Oprócz wodoru, elektroliza wody produkuje znaczące ilości tlenu. Celem tej pracy jest przeanalizowanie efektów, jakie dałoby wzbogacenie utleniacza w tlen, w stacjonarnych silnikach tłokowych o zapłonie iskrowym. Prace naukowe innych autorów, biorące pod uwagę wszystkie rodzaje spalania w silnikach spalinowych, wykazały niejednoznaczność w wynikach. Wspólna płaszczyzna została znaleziona dla: jednostkowej pracy generowanej przez silnik, przyrostów ciśnienia oraz wskaźników emisji. Przy wszystkich założeniach podczas badań wraz ze wzrostem zawartości tlenu: praca jednostkowa, przyrosty ciśnienia oraz wskaźnik emisji NOx zwiększyły swoją wartość. Pozostałe wartości wskaźników emisji szkodliwych substancji CO i HC okazały się niższe niż w spalaniu w normalnej zawartości tlenu. W ramach pracy opracowano model obliczeniowy bazujący na obiegu Otto celem określenia wpływu zawartości tlenu w utleniaczu na parametry termodynamiczne obiegu. Ponadto, wykonano badania eksperymentalne na silniku o zapłonie iskrowym zasilanym gazem ziemnym Gz50. Jako wynik badań otrzymano przebieg ciśnienia w cylindrze podczas jednego cyklu, strumień wykorzystanego paliwa, udziały molowe gazów toksycznych zawartych w spalinach oraz strumień dodatkowego tlenu.

EN

By the growing importance of unstable wind energy, efforts to creating energy storage system should be considered. One of the possibilities to achieving this goal would be the hydrogen production through water electrolysis process. Besides hydrogen water electrolysis produce significant amounts of oxygen. Aim of this work was the examine effect of oxygen enrichment in the SI engine. Previous research taking into account all the ways of combustion in internal combustion engines (SI, CI, and DF) showed ambiguity in the results. Common ground in the results was found with the case of specific work done by cycle, pressure rises and emissions. They have been found that in every conditions, with the increment of oxygen concentration, specific work done by engine grow as well as the pressure and NOx emission. HC and CO emission found to be lower. Change in efficient wasn’t constant. Authors showed that efficiency is very dependent on the test conditions and assumptions. In this work theoretical engine model was created to examine different oxygen concentrations for various gaseous fuels. Through model maximum temperature in cycle, specific work done by cycle and cycle efficiency were analyzed. Besides theoretical analysis experimental research was carried out. Experiment was conducted on the three cylinder SI engine which was originally adapted to work on the gasoline. As a result achieved: pressure course in the cylinder, emissions, oxygen and fuel flow. Nonetheless through them energetic parameters, maximum temperature and combustion model were analyzed.

6

Comparative performance with different versions of low heat rejection combustion chambers with crude rice bran oil

Murali K. M. V. S., Rao N. D. P., Prasad B. A., Murthy P. V. K.

Archive of Mechanical Engineering

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2014

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Vol. LXI, nr 4

627--651

EN

It has been found that the vegetable oils are promising substitute, because of their properties are similar to those of diesel fuel and they are renewable and can be easily produced. However, drawbacks associated with crude vegetable oils are high viscosity, low volatility call for low heat rejection combustion chamber, with its significance characteristics of higher operating temperature, maximum heat release, and ability to handle lower calorific value (CV) fuel etc. Experiments were carried out to evaluate the performance of an engine consisting of different low heat rejection (LHR) combustion chambers such as ceramic coated cylinder head-LHR-1, air gap insulated piston with superni (an alloy of nickel) crown and air gap insulated liner with superni insert – LHR-2; and ceramic coated cylinder head, air gap insulated piston and air gap insulated liner – LHR-3 with normal temperature condition of crude rice bran oil (CRBO) with varied injector opening pressure. Performance parameters (brake thermal efficiency, brake specific energy consumption, exhaust gas temperature, coolant load, and volumetric efficiency) and exhaust emissions [smoke levels and oxides of nitrogen [NOx]] were determined at various values of brake mean effective pressure of the engine. Combustion characteristics [peak pressure, time of occurrence of peak pressure, maximum rate of pressure rise] were determined at full load operation of the engine. Conventional engine (CE) showed compatible performance and LHR combustion chambers showed improved performance at recommended injection timing of 27 degrees bTDC and recommend injector opening pressure of 190 bar with CRBO operation, when compared with CE with pure diesel operation. Peak brake thermal efficiency increased relatively by 7%, brake specific energy consumption at full load operation decreased relatively by 3.5%, smoke levels at full load decreased relatively by 11% and NOx levels increased relatively by 58% with LHR-3 combustion chamber with CRBO at an injector opening pressure of 190 bar when compared with pure diesel operation on CE.

PL

Jak wiadomo, oleje roślinne są obiecującym substytutem paliw ropopochodnych, ponieważ ich właściwości są podobne do oleju dieslowskiego, są odnawialne i łatwe do wyprodukowania. Niemniej, surowe oleje roślinne wykazują wady, takie jak wysoka lepkość i mała lotność, co wymaga komory spalania o małych stratach ciepła, której istotnymi cechami są m.in. wyższa temperatura robocza, maksymalne wydzielanie ciepła i zdolność do wykorzystania paliwa o mniejszej wartości kalorycznej (CV). Przeprowadzono eksperymenty mające na celu ocenę osiągów silnika z różnymi komorami spalania o małych stratach ciepła (LHR), takich jak głowica cylindra o pokryciu ceramicznym (LHR-1), tłok izolowany szczeliną powietrzną z denkiem ze stopu Superni (superstop niklu) i tuleją cylindra z wkładką z Superni izolowaną szczeliną powietrzną (LHR-2) oraz głowica cylindra z pokryciem ceramicznym, tłok i tuleja cylindra izolowane szczelinami powietrznymi (LHR-3). Badania prowadzono przy normalnej temperaturze oleju roślinnego (surowy olej z otrąb ryżowych, CRBO) i zmiennym ciśnieniu w otworze wtryskiwacza. Parametry osiagów silnika (użyteczna sprawność termiczna, użyteczny współczynnik zużycia energii, temperatura gazu wydychanego, obciążenie obiegiem chłodziwa i współczynnik napełnienia) oraz emisje wydechowe [poziomy dymu i tlenków azotu, NOx] zostały wyznaczone przy różnych wartościach średniego użytecznego ciśnienia w silniku. Charakterystyki spalania [ciśnienie szczytowe, czas występowania ciśnienia szczytowego, maksymalna szybkość wzrostu ciśnienia] zostały wyznaczone w warunkach pracy silnika z pełnym obciążeniem. W porównaniu z silnikiem napędzanym olejem diesla, silnik konwencjonalny (CE) wykazał podobne osiągi przy pracy z olejem roślinnym (CRBO), a w komorach spalania o małych stratach ciepła (LHR) uzyskano lepsze osiągi przy zalecanym kącie wtrysku 27b stopni TDC (przed górnym punktem zwrotnym) i zalecanym ciśnieniu w otworze wtryskiwacza równym 190 bar. Szczytowa użyteczna sprawność cieplna wzrosła relatywnie o 7%, użyteczny współczynnik zużycia energii zmalał o 3,5% przy pracy z pełnym obciążeniem, poziomy dymu przy pełnym obciążeniu zmalały o 11%, a poziom tlenków NOx wzrósł relatywnie o 58% w przypadku komory spalania typu LHR-3 napędzanej olejem roślinnym CBRO przy ciśnieniu w otworze wtryskiwacza 190 bar, w porównaniu z parametrami uzyskanymi przy pracy z czystym olejem diesla.

7

Effect of Different Binders on the Combustion Characteristics of Ba(NO3)2/Mg-containing Pyrotechnic Mixtures

Ouyang D.

Central European Journal of Energetic Materials

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2013

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Vol. 10, no. 2

209--215

EN

The combustion characteristics of Ba(NO3)2/Mg with binders such as phenolic resin (PR) and nitrocellulose were studied experimentally using an IGA-140 non contact, far-infrared thermometer and transient intensity testing instrument. The results revealed that the burn temperature, luminous intensity and burn rate of the pyrotechnic mixtures with PR (1594.5 °C, 47235.6 cd, 12.5 mm/s) were all larger than the NC system (1432.6 °C, 3242.9 cd, 9.0 mm/s), which is due to differences in the decomposition progress of the two binders that led to substantial differences in the loss of reaction energy and the exothermic reaction between the phenolic resin and the oxidizer before the Mg-oxidizer reaction.

8

A comparative study of the performance of a low heat rejection engine with three different levels of insulation with vegetable oil operation

Murali Krishna M.V.S., Janardhan N., Murthy P.V.K., Ushasri P., Sarada N.

Archive of Mechanical Engineering

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2012

|

Vol. LIX, nr 1

101-128

EN

Investigations were carried out to evaluate the performance of a low heat rejection (LHR) diesel engine consisting of different versions, such as ceramic coated cylinder head engine-LHR-1-Air gap insulated piston and air gap insulated liner-LHR-2- and Ceramic coated cylinder head, air gap insulated piston and air gap insulated liner -LHR-3 with degrees of insulation with normal temperature condition of linseed oil with varied injection pressure. Performance parameters were determined at various magnitudes of brake mean effective pressure. Pollution levels of smoke and oxides of nitrogen (NOx) were recorded at the peak load operation of the engine. Combustion characteristics of the engine were measured with TDC (top dead centre) encoder, pressure transducer, console and special pressure-crank angle software package. Conventional engine (CE) showed deteriorated performance, while LHR engine showed improved performance at recommended injection timing of 27 degrees bTDC and recommend injection pressure of 190 bar with vegetable oil operation, when compared with CE with pure diesel operation. Peak brake thermal efficiency increased by 14%, smoke levels decreased by 10% and NOx levels increased by 30% with LHR engine at an injection pressure of 270 bar when compared with pure diesel operation on CE at manufacturer's recommended injection timing.

PL

Wykonano badania mające na celu ocenę osiągów silnika wysokoprężnego o małych stratach ciepła (Low Heat Rejection, LHR). Badano różne wersje izolacji cieplnej, takie jak głowica cylindra z powłoką ceramiczną (LHR-1), tłok i tuleja cylindra izolowane szczelinami powietrznymi (LHT-2), głowica cylindra z powłoką ceramiczną oraz tłok i tuleja cylindra izolowane szczelinami powietrznymi (LHR-3). Badania wykonano dla różnego stopnia izolacji, w normalnych warunkach temperaturowych, przy różnych ciśnieniach wtrysku paliwa (oleju lnianego). Parametry robocze wyznaczono dla różnych wartości ciśnienia użytecznego. Poziomy zanieczyszczeń dymem i tlenkami azotu (NOx) były mierzone w warunkach szczytowego obciążenia silnika. Przy pomiarze charakterystyk spalania silnika wykorzystano koder TDC (górnego martwego punktu), przetwornik ciśnienia, konsolę i specjalny pakiet programowy do wyznaczania zależności ciśnienie - kąt obrotu wału korbowego. Silnik konwencjonalny (CE), napędzany czystym olejem dieslowskim, wykazywał gorsze działanie. W porównaniu z nim, sinik o małych stratach ciepła (LHR), napędzany olejem roślinnym, miał lepsze parametry robocze przy zalecanym kącie wyprzedzenia wtrysku 27 stopni przed GMP i zalecanym ciśnieniu wtrysku 190 bar. Dla silnika typu LHR z optymalnym kątem wyprzedzenia wtrysku i przy maksymalnym zasysaniu etanolu, szczytowa sprawność cieplna była większa o 18%, poziom zawartości dymu mniejszy o 48%, a zawartość tlenków azotu mniejsza o 38% w porównaniu z silnikiem konwencjonalnym (CE), z czystym paliwem dieslowskim, przy zalecanym przez producenta kącie wyprzedzenia wtrysku.

9

Combustion characteristics for small diesel engine by using emulsified blend fuels of vegetable oil and light oil

Kawakami T.

Journal of KONES

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2011

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Vol. 18, No. 4

185-190

EN

The paper is focusing on combustion characteristics for small diesel engine by using emulsified blend fuels of vegetable oil and light oil. Target is to achieve low emissions and low fuel consumption for internal combustion engines. The fuels used in this study are light oil, blend fuels [light oil + coconut oil, light oil + palm oil], and emulsified fuels [light oil + water, blend fuels + water]. Mean increasing rate of pressure is calculated from the value which subtracted initial pressure from maximum burning pressure divided by total burning time. The mean increasing ratio of pressure is calculated from the value which subtracted initial pressure from maximum burning pressure divided by the total burning time. The emissions in exhaust gas are measured with an analyzer of exhaust gas. The data of 30 tests for each engine revolutions were averaged arithmetically. Experimental approach and results have been presented by details. The main conclusions are as follows: it is possible to control the combustion behaviour by using blend fuels and emulsified blend fuels for small diesel engine; the maximum burning pressure of emulsified blend fuels increases at low engine speed; the CO emission of blend fuels is smaller than that of light oil; the NOX emission of emulsified coconut blend fuel and emulsified palm blend fuel is smaller than that of light oil; the CO emission of emulsified Coconut-Palm blend fuel is equal to that of light oil at low engine speed.

10

Effects of Water Vapor and CO2 Addition on Combustion Characteristics for Lean Hydrocarbon-Air Mixtures under Normal and Microgravity Conditions

Shibata Y., Kawakami T., Teodorczyk A.

Archivum Combustionis

|

2008

|

Vol. 28 nr 3-4

197-205

EN

Experiments on combustion of extremely lean mixtures in the vicinity of flammability limits have acquired importance from the viewpoint of development of new kinds of combustion systems having low fuel consumption and low emissions. Furthermore, the determination of combustion characteristics for vapor addition under normal gravity and microgravity is very important for control of safety engineering in the space. In this work, experiments have been carried out with extremely lean, quiescent hydrocarbon-air mixtures to examine the effects of water vapor and CO2 addition on combustion characteristics under normal gravity and microgravity conditions. The microgravity technique achieved in a freely falling chamber is employed because the realizations of symmetrical flame propagations in a tube are impossible. Experimental condition for the initial mixtures corresponds to room temperature and 0.1MPa and the fuels used are methane and propane of 99.9% purity, respectively. The experimental results in this study are as follows. : 1) The water vapor addition for low oxygen concentration of propane-air mixtures effectively increases the flame speed; 2) Effects of water vapor addition on flame speed depend on a fuel property; 3) It is possible to control the combustion behavior by water vapor addition in the mixtures under low oxygen concentration.

11

Influence of oxygen concentration on combustion characteristics of hydrocarbon-air mixtures under high temperature and pressure

Kanno A., Kawakami T., Sutkowski M., Teodorczyk A.

Journal of KONES

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2006

|

Vol. 13, No. 2

197-203

EN

The emission of NOx, SOx, HC and CO2 from internal combustion engines is still a major issue in the development of modern engines. Especially for new concepts, like EGR (Exhaust gas recirculation), developed, detailed information about the pollutant formation is required. However, the experiments of actual standard engines are generally very complicated processes including the residual gas from the last cycle and the flow in an engine cylinder. Thus, experimental data measured using actual engines become unreliable. To obtain the essential data on combustion of hydrocarbon-CO2-N2-O2 mixtures, the experiments have been performed under conditions of high temperature and pressure, which are achieved by a spark ignited opposed rapid compression machine. The main conclusions are as follows: (1) The maximum burning pressure decreases with decreasing oxygen concentration at same EGR ratio. (2) The total burning time decreases with decreasing the concentration of O2 in methane-COx-N2-O2 and propane-CO2-N2-O2 mixtures. (3) The reduction ratio of flame speed is relatively larger on the fuel rich side than that on the lean side. Numerical modeling was focused on the influence of EGR ratio on exhaust emission. Methane fuel was used in the modeling

12

Experimental investigation of combustion characteristics for spray combustion by impinging injection in a closed vessel

Morioka K., Kawakami T., Teodorczyk A.

Journal of KONES

|

2006

|

Vol. 13, No. 2

335-339

EN

Internal combustion engines are the major source of air pollution. Especially, compression ignition engines in today’s automobiles contribute the most to particulate emission and soot, and it is recognized that these emissions have a detrimental effect on human and earth environment. So, an improvement of spray combustion for diesel engines is of urgent necessity. Experiments have been conducted to obtain essential data on spray combustion influenced by impinging injection in a closed vessel. The effect of the impinging injection on maximum burning pressure, total burning time and flame speed is investigated at the condition of 300 K of initial temperature and 0.1 MPa of initial pressure. The travel time of flame front is measured by ionization probes located at two different positions from the center of combustion chamber. The experimental investigations pointed out that the maximum burning pressure for impinging injection is larger than that of the single injection at the same overall equivalence ratio, the total burning time increases with increasing the overall equivalence ratio (after injection) at same equivalence ratio (before injection), the combustion of impinging injection is very effective for increasing the flame speed.