Volume 11 Issue 2 ( June )

This paper studies the thermal null offset of half-filled water tank left in ambient environment. The study was performed by analyzing multi-days reading from various sensors employed on the system. Repeated reading pattern produced by each sensor indicated that dynamics of ambient temperature affects the thermal null offset of the open and closed water tank. However, the sequential quasi steady state is different for open and closed tank. For the open tank, daily thermal equilibrium condition was achieved with significant temperature difference between the sensors located below the water surface. Yet, insignificant temperature difference was found in closed tank. Hence, it indicates that the lid-closing accelerates the thermal equilibrium inside the tank. The thermal null offset of water tank will be used as a basis for developing new model of heat transfer from hot fluid inside the tank to ambient air which commonly found in various industries.

Keywords: thermal null offset; dynamic environment; water tank