2.1. Heat Flow Meter
2.2. FEM Simulations
- System geometry;
- Layer configuration;
- Chemical/physical material properties;
- Thermal conductivity and global transmittance for comparing the obtained results.
- A geometry simplification for the reinforced concrete seats: the rounded shape of the corner has been replaced by an angular one;
- A simplification of the EPS seat: a straight line has been used, running in the middle of the original swallow-tail shape.
3.1. Heat Flow Meter Measurements
3.2. FEM Simulations
- Case 1: outside wall temperature Tout = 0 °C, inside wall temperature Tin = 20 °C;
- Case 2: outside wall temperature Tout = −5 °C, inside wall Tin = 20 °C;
3.2.1. FEM Simulation of a Single Block (SBC)
3.2.2. FEM Simulation of Nine Adjacent Blocks (9BC)
- Case 3: outside wall temperature Tout = 6.2 °C, inside wall temperature Tin = 18.4 °C;
- Case 4: outside wall temperature Tout = 6 °C, inside wall temperature Tin = 18.7 °C.
- Results did not vary with different wall temperatures, therefore they are not influenced by the imposed boundary conditions;
- Results did not vary with different block configurations. This means that relevant mutual exchanges between adjacent blocks do not occur, and that the study of this kind of material can be focused even on a single block;
- Results are coherent with the value provided by the manufacturer, this means that the fem simulations (in terms of modeled block and boundary conditions) well represent the conditions of the theoretical calculus;
- The models and geometries employed for the SBC ensure the numerical stability of the simulation;
- The geometrical simplifications adopted for the study of configuration 9BC, needed to reduce the computational effort of the simulations, guarantee a proper modeling of the wall behavior;
- Results obtained via fem simulation differ from the ones obtained via in field measurements, since the latter are affected by the dynamic thermal behavior of the wall;
4. Shape Optimization
- the manufacturer,
- on-site HFM measurement on a real building made of this kind of material, and
- FEM simulations.
- homogeneous, continuous and isotropic materials,
- steady-state condition,
- one-dimensional heat flow and absence of material discontinuities.
Conflicts of Interest
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