Study of transient heating using an in situ combustion system

In this work, we evaluated the transient heating of a liquid using an in situ laboratory-scale combustion system, and the sensible and latent heat transfer efficiencies were determined through experimental evaluation of the heating of water volume and psychrometric parameters of combustion gases. Tests were performed using natural gas with a composition of 97% (by volume) of methane, and the liquid level was varied to study the effects on efficiency. Experimentation was carried out at atmospheric conditions of 298 K and 850 mbar with combustion gases at 446°C and equivalence ratio φ=0.83. It was found that sensible and latent heat transfer efficiencies decrease with time and with increasing liquid temperature; moreover, condensation efficiency increases with increasing liquid level.