1. The “Lumburnator” a Next Generation Wood Stove
Student Team:
Jake Lindberg, JinYing Lin, Kevin J. Lee, Yunxiao Jiang, Jason Peng
Advisors:
Dr. Devinder Mahajan, Dr. Tom Butcher, Dr. Jon Longtin, *Dr. Vladimir Zaitsev
AirflowAfterburner
Divider
Future Work
The next phases of this project are to evaluate the emissions control devices
seen here and to incorporate these concepts into a standalone wood stove of
our own design. However given the recent market trend towards pellets
stoves over wood stoves, consideration will be given to making a transition
to a standalone pellet stove featuring our emission control devices.
Acknowledgements
Funding for the “The Lumburnator, a Next Generation Woodstove” project
has been provided by the New York State Energy Research and Development
Authority (NYSERDA award № 63043).
Additional thank you to Dr. Sotirios Mamalis and Dr. Benjamin Lawler for
sharing their lab space with us for our on-site testing at SBU.
Our forced secondary
combustion system, the
afterburner, is unique in that it
is propane fired. The use of
propane allows us to start on
demand, eliminating any warm-
up period and allowing it to
begin cleaning in the startup
phase. Using propane in the
afterburner will also help us
troubleshoot a propane fired
igniter system which will
improve the divider technique.
The Venturi Draft Inducer
introduces forced air into the flue
stack to affect airflow through the
stove, and therefore, gas velocity
in combustion chamber can be
regulated to achieve a cleaner
burn.
With the inducer and fan
combination shown above we
can induce airflow 5x greater
than typical exhaust flow
rates. High dilution ratio is a
good basis to say we can raise
and lower draft.
Baffles increase
turbulence and
residence time in the
firebox. Dual chambers
separate fuel slowing
combustion, adds
turbulence and creates
potential for staged
combustion.
The latest tests shows
percentage of excess air
increases as tests progress
resulting in decreased
efficiency. With the draft
inducer we will be able to
introduce more air in the initial
phase and cut draft at the end
phase.
Where Chamber #1 temperature is higher that chamber is
undergoes primary combustion, while Chamber #2 dries.
Ignition in Chamber #2 results in gasification in Chamber #1
The result is a longer peak temperature than un-divided tests
and a longer burn overall.
Abstract
Our goal is to design an exceedingly efficient wood burning stove. We have identified air intake control and an afterburner as the most promising systems to reduce carbon monoxide (CO), Volatile Organic
Compounds (VOCs), and particulate matter (PM) in wood stove exhaust. It is known that a good wood burning stove must operate near the stoichiometric air ratio. Deficit of air leads to high concentration
of CO, VOC, and PM in exhaust gases. Excess air leads to unreasonably high burn rates and reduced residence time and thus poor combustion of secondary products and lower energy efficiency due to heat
loss with exhaust gases.
In order to evaluate the effect of our
emission control devices we need to
test our exhaust gases, but ultimately
our testing station will be incorporated
into the stove to measure process
control variables to optimize stove
operations in real time via our airflow
control systems.
Our portable test stand gives us the
capability to continuously measure:
• 4 stove temperatures
• burn rate
• draft and dilution ratio.
And take “snapshot” measurements of:
• CO
• O2
• PM.
Shown to the right is our
afterburner in action.
While this version is
durable it shown signs of
rich combustion, i.e.
yellow flames, which may
be a problem in the low
oxygen flue gases. As of
now we are modifying the
assembly seen in Figure D
to improve the air/fuel
ratio.
Methods
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Temperature(̊C)
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Flue
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