Chapter hvac engineering Fundamentals: Part 1 Introduction

10.5.1
The combustion process
The combustion process follows basic principles called the
three T’s of
combustion.
The first one is
time
—the time required for the air to
properly mix with the fuel and for the combustion process to be com-
pleted. It is critical when waste materials are being combusted in con-
junction with standard fuels. The second is
temperature
—the temper-
ature at which the fuel will ignite, oxidation is accelerated, and the
process of combustion begins. Ignition temperatures are well estab-
lished for standard fossil fuels but must be carefully considered when
waste or other organic-type materials are being burned. The third is
turbulence
—the process of thoroughly mixing the air and fuel so that
each particle of fuel is in contact with the right amount of oxygen and
combustion can continue to completion. The turbulence must be vio-
lent enough to ensure good contact between the fuel and the oxygen.
Assuming there is enough combustion air to work with, inadequate
turbulence is the most common cause of incomplete combustion. In-
adequate turbulence can result in the generation of excessive amounts
Equipment: Part 2
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