PRODUCTS OF COMBUSTION OF GASEOUS FUELS AND CALCULATED FLAME TEMPERATURE

PRODUCTS OF COMBUSTION OF GASEOUS FUELS
AND CALCULATED FLAME TEMPERATURE
Gheorghe CAUNEI FLORESCU1, Lt. Eng. Constantin NISTOR, PhD. Student2,
Associate Professor Amado George STEFAN2
1

GENERAL DIRECTORATE NATIONAL SYSTEM HAIL - MINISTRY
OF AGRICULTURE AND RURAL DEVELOPMENT, 2 MILITARY TECHNICAL ACADEMY

Abstract. The work contains elements of combustion stoichiometry. It defines the ratio of the mass of the fuel mc and air mass ma, called fuel-air dose, d. Commercial liquid fuels for engines of petroleum origin, as natural gas is generally complex mixtures of hydrocarbons and other organic substances. For the calculation of combustion air and combustion products is consider a pure substance considered as representative of a particular class of commercial fuels. Can be represented by octane gasoline (C8H18), diesel with cetane (C16H34), or dodecanese (C12H26), natural gas by methane
(CH4). Corresponding quantities of products are  νCO2 , νCO  ν H O ,  ν H , mol/mol fuel. T fa adiabatic flame
2

2

temperature is determined by solving the equation vp  [hp(Tp)  hp(Ts) vr  [hr (Tr )  hr (Ts)  Qps  0.
Keywords: Stoichiometric combustion, Thermodynamics.

1. INTRODUCTION

Air needed for combustion, as the composition of the combustion products are determined by the equation expressing global fuel oxidation reactions, respecting the principle of conservation of mass for each of the elements of reactants.
If the fuel composition is a hydrocarbon Cm H n generated global full oxidation reaction has the form

Cm Hn  a  O2  b  CO2  c  H2O ,

(1)

where: stoichiometric ratios (1, a, b, c) are expressed in moles.
Conservation of mass of carbon is expressed by the condition b = m, and hydrogen in the condition c = n/2. Conservation of mass requires oxygen provided a = m + n / 4. Equation (1) takes the form

Cm Hn + (m  n /4)  O2 = m  CO2 + (n /2)  H2O .
(2)
Dry atmospheric air contains 20.95% (volume)
oxygen,

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