To understand and compute the behaviour of a BILS, a simplified model is developped. This model is considering the BILS as a homogeneously filled cylindre filled with water floating in a calm lake at a fixed temperature. The walls of the cylinder are made of up to six different layers of materials. The bottom and top are considered to be made of one single material.

The tool requires 

• T0-inside and T0-outside in [°C]. The intial temperatures inside and outside of the storage 

• h-inside and r-inside in [m], The inner height and radius of the storage

• d1 to d5 and dTop, dBottom in [m], The thickness of the insulation layers

• λ1 to λ5 and λTop, λBottom in [Wm-1K-1]. The heat conductivities

• αin and αext in [Wm-2K-1]. The heat transfer coefficients inside and outside

• Heating in [W[. Constant heating

• Timesteps in [s] used for calculation

• FillFactor [0-1]. Filling ratio