Thermal radiation is part of the broader phenomenon of the propagation of electromagnetic radiation emitted by bodies and is transmitted from a warmer body to a colder body at the speed of light without heating the air.
The electromagnetic radiation, which corresponds to the transmission of heat, is called thermal radiation: it is emitted due to the vibratory and rotational motions of the molecules and atoms of a substance and is extended in a range of wavelengths from 10-2? m (in Ultra Violet: UV) to 102? m (Infrared).
The property of electromagnetic radiation is that it propagates in all directions, it is not absorbed by the air, but only by solid bodies which immediately transform it into thermal energy. If we consider a hot body placed in an environment whose walls are at a uniform temperature and lower than that of the body after some time, it will be possible to see that the body has cooled down and has reached thermal equilibrium with the walls .
A body at a certain temperature T emits and receives electromagnetic radiation with a certain intensity that can be variable over time, regardless of the medium in which it is located, therefore also in a vacuum.
Irradiation is characterized, compared to the other two heat transmission mechanisms, precisely by being able to take place even in the absence of matter between the systems affected by the heat exchange. Often in practical applications the three transmission mechanisms of thermal energy take place simultaneously with different intensity. In a vacuum, on the other hand, the transmission of heat can only take place by radiation. A total absorber or black body can therefore be defined as a body that has an absorption coefficient a = 1 relative to each wavelength.
An object of this kind absorbs the radiation of any body without reflecting it, despite being a large emitter and at high temperatures it can be colored by emission. A gray body, on the other hand, is a body that has the coefficient a <1, but constant at all wavelengths. Finally, the white body has a = 0 for all frequencies and therefore zero absorption.
As is known, the human being produces heat on its own and partially disperses it in the environment by conduction, convection, radiation and evaporation through sweating. When the body ends up losing too much heat, there is a sensation of cold; on the other hand, when it disperses too little of it, there is a sensation of heat. The difficulty of those who deal with heating lies in keeping humans within a specific climatic zone indicated by a graph known as the Bedford-Bachman Optimal Living Comfort Curve. By following this need, analyzing the optimal Comfort curve, it is highlighted that it is linked to an interaction between the air temperature and the average radiant temperature of the walls. For example, Thermal Comfort can be achieved by having:
A wall temperature of 28 ° C and an air temperature of 11 ° C (1);
A wall temperature of 20 ° C and an air temperature of 15 ° C (2);
A wall temperature of 11 ° C and an air temperature of 22 ° C (3).
As can be seen from the diagram, all three possibilities place the man in the area of maximum comfort. The perception of Comfort and Wellbeing in an environment is in fact linked not only to the air temperature (ta), but also to the temperatures of the surfaces surrounding the body (average radiant temperature - tmr), or to the so-called Operating Temperature, which derives by the combined effect of both temperatures. This type of heat propagation which consists in the transmission of infrared radiation is called RADIATION.
Traditional heating systems that work mainly by convection, not being able to effectively raise the temperature of the walls, create the comfort zone by raising the air temperature.
This system has the disadvantage of not being energy efficient, as the air does not have the ability to store large amounts of energy and therefore needs to be continuously heated. Heating the air also increases the circulation of dust, the dryness of the air itself and an important thermal gradient is established between the different areas.
The most energy efficient and also the most effective system for keeping the human being in the comfort zone is to raise the temperature of the walls. They accumulate heat and transfer it to the human body that perceives it. The best demonstration of this can be deduced from the fact that, on a beautiful winter day, passing from a shady area to one in full sun, we experience an immediate sensation of warmth.
Traditional heating systems with natural convection (radiators) or forced convection (fan coils) use air as a vector for transporting the energy necessary to heat the environment, thus favoring the phenomenon of thermal stratification with a thermal gradient of about 1.8 ° C for each meter of room height.
This means that, in a room three meters high, there will be a temperature difference between the floor and the ceiling of about 5.5 ° C. With CARISMA ORIGINAL® radiant plates this phenomenon is considerably reduced up to about 0.5 ° C per meter, with the result that in the same environment there would be only 1.5 ° C degrees of difference between the temperature of the floor and that of the ceiling.
In homes with irradiation systems, the consistent reduction of the thermal gradient favors a substantial decrease in the thermal load necessary for heating the rooms as well as the well-being and comfort that is obtained in an environment where the temperature is more uniform.
Because their particularities can be summarized as follows:
Being powered at low temperatures, they can be used not only with normal boilers but also with the most advanced and efficient hot water production systems: condensing boilers, heat pumps, solar thermal, geothermal, wood stoves, pellet stoves. .
Unique in their ease of installation, they are ideal for both new homes and for replacing radiators in existing ones.
Thanks to a maximum depth of 50 mm, they do not steal space and pose no danger due to the total absence of sharp edges.
By exchanging heat by radiation, they allow less dehumidification of the air, improving living comfort and well-being.
Using radiant technology, they heat the walls which in turn reflect the energy and drastically reduce the formation of mold.
By limiting the convective effect, they do not dirty the wall.
Their design makes cleaning easy, just wipe them with a damp cloth to eliminate mites and dust.
By limiting thermal stratification, they reduce the maximum temperature difference between floor and ceiling.
The supply temperature at 45-50 ° C does not involve any risk of burns by contact.
Thanks to their ductility, the temperature regulation is concealed. Compared to conventional radiators, CARISMA ORIGINAL® radiant plates are also able to raise the temperature of the walls more effectively.
The air conditioning with CARISMA ORIGINAL® radiant plates, radiant technology heating elements, allows to comply with the provisions concerning Energy Saving, Reduction of Emissions into the atmosphere and to guarantee better Thermal and Environmental Comfort.
Technical characteristics of the heating body
CARISMA ORIGINAL® is an emissive body exposed on the walls, totally closed at the sides, with a flat front surface.
Energy transmission occurs through radiation, with a maximum thermal stratification effect not exceeding 0.65 ° C / m.
Construction features of the heating body
CARISMA ORIGINAL® is made with steel profiles obtained from cold drawn strip, with a specific section to maximize heat exchange.
The painting is with epoxy powder polymerized in the oven at 180 °.
The pressure resistance is 8 bar.
The water content of 8.4 l / m2.
The 1/2 ”connections are located behind the heating body, accessible only with a screwdriver or Allen key.
The air vent valve is located on the top manifold.
The 100% recyclability of the product.
CARISMA ORIGINAL® is anchored to the wall with a system that allows it to be quickly removed in the event of ordinary and / or extraordinary maintenance of the walls.
The maximum projection from the wall, i.e. the depth is 50 mm.
Accident prevention is due to the absence of sharp edges.
The sides are rounded to have a lower angle of incidence in the event of collisions with flat surfaces and without roughness or cracks.
There is the total absence of valves and / or external holders
The prevention of injuries caused by burns is due to a temperature of use not exceeding 55 ° C;
The air bleed valves and the water drain plugs cannot be opened except by means of a special key.
The average operating temperature in standard installation is 50 ± 5 ° C.
The radiators are equipped with:
wall fixing brackets joined according to a template to facilitate installation
n ° 1 air vent valve with 1/2 "connection
n ° 1 water drain plug with 1/2 "connection
Use and maintenance
For the installation, operation and maintenance of heating systems with bodies
radiant heaters, it is advisable to comply with the regulations in force for any other type of steel heating body.
In particular, for installation, keep in mind that:
radiant technology heating elements can be used in hot water and steam systems (maximum temperature of 120 ° C); the maximum operating pressure is 6 bar. radiant technology heating elements must be installed in such a way as to adhere perfectly to the rear wall. if the rear wall is not sufficiently insulated, proceed with additional insulation in order to minimize heat loss to the outside;
the pH value of the water must be basic and must not have corrosive characteristics towards metals. When using the radiant technology heating body, remember never to use abrasive products other than to clean the surfaces.