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S. M. Kalinovi´ c et al.
times lower for walls with the plant cover. That means that the ability of the outside
wall surface to accumulate thermal energy is four times lower during the periodic
variation of the outside temperature, i.e. a small amount of the heat will accumulate
on the outside surface of the wall, while a larger amount will be transferred through
other layers to the interior.
The heat capacity of the outside wall surface has approximately the same value
for all the three types of walls with a plant cover, which is almost four times lower
than in the case of walls without it. The heat capacity on the inside has the same
value as for walls without the plant cover.
The factor of the external temperature oscillation amplitude decrease, i.e. the
decrement factor, is the highest on wall 6 and the lowest on wall 4. The decrement
factor is 30% lower for living walls than for the same walls without the plant cover.
The delay factor for changing the outside temperature on wall 4 is slightly different
from the same quantity for wall 6, while for wall 5 the delay factor is slightly higher. A
comparison of values, shown in Figs. 2 and 3, shows that the delay factor in variation
of the outside temperature is 11% higher for the living walls. Based on this, it can
be concluded that the walls with the plant cover are walls with greater possibility of
absorption of the thermal energy; the thermal mass of the walls is greater and the
longer they emit the heat towards the interior, the more stable the change of thermal
comfort (the change will be more moderate, with little chance for appearance of
peaks and sudden changes of the interior temperatures).
4 Conclusions
The paper analyzes the ability to temporarily delay the external thermal effect,
together with the factors of reducing the extreme external temperatures on the inside
of the wall in the living walls. It is shown that the achievement of the corresponding
values of the wall heat transfer coefficient is related to its structure.
In order to find the optimal solution for the wall structure, with the highest energy
saving potential, three types of walls, with different structure and the same total
thickness, with and without the plant cover, were analyzed.
Based on results presented in this paper, it can be concluded that the phase delay
on the outside of the wall, i.e. the outer admittance, is equal for all the walls and that
the phase delay on the outside of the wall is almost four times lower for walls with
the vegetation cover. The heat capacity on the inside has the same value for walls
with and without the plant cover, while the heat capacity of the wall surface on the
outside for living walls has approximately four times lower value than in the case of
walls without the plant cover. The decrement factor is 30% lower for the living walls
than for the same walls without the vegetation cover, while the delay factor is 11%
higher for the living walls.
Due to of all these, more attention must be paid to studying the dynamic characteristics of certain types of walls and to trying to find the best solutions that would
meet the prescribed regulations and requirements should be an objective, as well.
S. M. Kalinovi´ c et al.
times lower for walls with the plant cover. That means that the ability of the outside
wall surface to accumulate thermal energy is four times lower during the periodic
variation of the outside temperature, i.e. a small amount of the heat will accumulate
on the outside surface of the wall, while a larger amount will be transferred through
other layers to the interior.
The heat capacity of the outside wall surface has approximately the same value
for all the three types of walls with a plant cover, which is almost four times lower
than in the case of walls without it. The heat capacity on the inside has the same
value as for walls without the plant cover.
The factor of the external temperature oscillation amplitude decrease, i.e. the
decrement factor, is the highest on wall 6 and the lowest on wall 4. The decrement
factor is 30% lower for living walls than for the same walls without the plant cover.
The delay factor for changing the outside temperature on wall 4 is slightly different
from the same quantity for wall 6, while for wall 5 the delay factor is slightly higher. A
comparison of values, shown in Figs. 2 and 3, shows that the delay factor in variation
of the outside temperature is 11% higher for the living walls. Based on this, it can
be concluded that the walls with the plant cover are walls with greater possibility of
absorption of the thermal energy; the thermal mass of the walls is greater and the
longer they emit the heat towards the interior, the more stable the change of thermal
comfort (the change will be more moderate, with little chance for appearance of
peaks and sudden changes of the interior temperatures).
4 Conclusions
The paper analyzes the ability to temporarily delay the external thermal effect,
together with the factors of reducing the extreme external temperatures on the inside
of the wall in the living walls. It is shown that the achievement of the corresponding
values of the wall heat transfer coefficient is related to its structure.
In order to find the optimal solution for the wall structure, with the highest energy
saving potential, three types of walls, with different structure and the same total
thickness, with and without the plant cover, were analyzed.
Based on results presented in this paper, it can be concluded that the phase delay
on the outside of the wall, i.e. the outer admittance, is equal for all the walls and that
the phase delay on the outside of the wall is almost four times lower for walls with
the vegetation cover. The heat capacity on the inside has the same value for walls
with and without the plant cover, while the heat capacity of the wall surface on the
outside for living walls has approximately four times lower value than in the case of
walls without the plant cover. The decrement factor is 30% lower for the living walls
than for the same walls without the vegetation cover, while the delay factor is 11%
higher for the living walls.
Due to of all these, more attention must be paid to studying the dynamic characteristics of certain types of walls and to trying to find the best solutions that would
meet the prescribed regulations and requirements should be an objective, as well.