Abstract:
Contributions were made to the performance improvements of the Injera baking stove. A
strong understanding of heat transfer modes was established and used to evaluate design
enhancements, aided by software applications like Computational Fluid Dynamics (CFD)
and online tools like combustion toolbox. A new Injera baking stove was designed and
constructed to use biomass as fuel. The design aimed to increase thermal efficiency,
reduce specific fuel consumption, emissions, and cooking time compared to the Mirt
stove. In general, the new stove demonstrated significant improvements in thermal
efficiency, fuel consumption, cooking time, and Injera quality compared to the currently
servicing Mirt stove. Additionally, the reduction in fuel consumption could lead to a
significant reduction in greenhouse gas emissions. As the test result showed combustion
efficiency improved by 7.48% with an increase in fire power. The thermal efficiency of
the new stove was measured at 28.42%, compared to 23.47% for the Mirt stove. Fuel
consumption decreased by 7.21% (39.08 g/kg-food) while the fire power increased by
5.55% (1.99 KW). Cooking time reduced from 2.716 minutes to 2.386 minutes per Injera,
saving 12.15% time per baking activity. Average time to bake 1 kg of Injera reduced
from 4.41 minutes to 3.92 minutes. Injera quality analysis showed improvements in
moisture content (2.8%), consistency (4.89%), and taste preference. Fuel savings would
result in a greenhouse gas emissions reduction of 0.198 tCO2e/year