The Effect of Insulation Thickness on Heat Transfer Characteristics and Flammability in Tube Mesoscale Combustors

Abstract

Micropower generator is a micro-scale energy source that has two main components, namely a micro/mesoscale combustor and thermophotovoltaics (TPV). The micro-scale combustor is one part that functions as a combustion chamber that produces heat in micropower plants. Heptane is used as fuel, while the combustor combustion chamber with a diameter of 3.5 mm is made from duraluminium-quart glass tube. Combustion stability in the combustion chamber is influenced by several factors, such as temperature, geometry, and combustion chamber design. In order to maintain flame stability, mesh is added to the combustion chamber. One way to minimize heat loss in the combustion chamber is to add an insulating layer to the combustion chamber. This research aims to prove the role of adding an insulating layer in flame stability in mesoscale burners. It is necessary to add an appropriate insulating layer to minimize heat loss so that it remains stable in the mesoscale burner. This experimental test shows that the temperature distribution when adding an insulation layer with a thickness of 3 mm has a higher temperature on the outside compared to a thickness of 6 mm. Meanwhile, the temperature inside the combustor chamber with a thickness of 6 mm is superior to that with a thickness of 3 mm. The flame limit of the combustor with a mesh distance of 5 mm for liquid heptane fuel was successfully stable at an equivalent ratio of ɸ0.97 – 1.5 with a maximum speed of 31.7.