Effective temperature

Effective temperature - a complex parameter thermal sensations, uniting in a single numeric value of the temperature, humidity and movement of air and radiant heat (radiation temperature)Opredelyaetsya special temperature scale (according to nomograms). So, if the air temperature is 25 degrees, absolute humidity, equal to 15 mm RT. senior speed of 0.5 m/s and mean radiant temperature of 15 degrees effective temperature is equal to 19.5 degrees.
The term "effective temperature emerged after the inclusion in the concept of the effective temperature (taking into account the influence of temperature, humidity and speed of air movement) such an important factor of the radiation temperature. The effective temperature is determined with the help of special nomograms. So, when dry bulb temperature of 35 degrees and the temperature of the wet thermometer 28 degrees effective temperature of still air, will be equal to 30.5 degrees of air moving with a speed of 3 m/s,- 28 degrees.
In practice usually is determined by the so-called operational temperature specified by the index, showing the complex effect of air temperature, radiation, temperature and air flow. In the presence of significant sources of thermal radiation, where the temperature of the air and surfaces (walls) differ considerably, the operative temperature is a better indicator than the effective temperature.

Effective temperature (resulting temperature) - special temperature scale in which each indicator (in degrees) is the combined effect on a person's temperature, humidity, air movement and radiant heat (radiation temperature). The term effective temperature proposed by Masterom (A. Missenard); they have been included in the concept of the effective temperature of the fourth fundamental factor - radiation temperature. The doctrine of effective temperatures developed in the USA. Effective temperature scale teploobmenu created humans when exposed to heat, humidity and air movement. The scale of the effective temperature developed experimentally by defining teploobmena people in psychrometric of the cell wall and the air had the same temperature. Introduction in this scale mean radiant temperature led to the creation of the concepts of effective temperature. Walls ordinary buildings do not have a uniform temperature, so effective temperature locally modified; the effective temperature is more evenly distributed in the premises.
On Missionary, there are two scales effective temperature: R. I. transition and R. T. stay. The first is installed by subjective teploobmenu get observers, moving from one room to another and back. The second is determined by the group of persons who are experienced in the room long enough period of time (not less than 1 hour) to establish an equilibrium between the body and the thermal regime of the room. Physiological balance of the person is determined by the level of physiological reactions (the balance of heat, the temperature of the skin and body, changes of blood circulation, breathing, etc.).
Sometimes distinguish the scale of effective temperatures, consisting of a heat sensation in humans in calm air with the effect only temperature and humidity, and the scale equivalent-effective temperature, containing indicators of impact on teploobmena the same factors, but in the moving air. On Missionary, both scales can be attributed to the resulting temperature change; they are used to control thermal conditions in the premises with the same temperature of the walls and air.
Observations have shown that warm feeling of a person affected by painting the walls of the room, its size, mental suggestion, etc. So when setting the level of the resultant temperature should create conditions, when these side effects are eliminated.
The scale and the resulting effective temperatures are divided into thermal zones: comfort heating and cooling. These scales are installed properly dressed and naked people. First, the scale has been called normal, and the second core. The comfort zone are those values of resultant and effective temperatures, which in most people, provide normal and pleasant heat is a feeling that is confirmed by a number of physiological observations. Zone heating and cooling contain indicators in degrees Celsius, at which person are observed physiological phenomena increased cooling or overheating.
To find the individual values of effective temperatures necessary to determine the place of study the temperature, humidity, air movement and mean radiant temperature. The temperature and humidity is determined by the psychrometer of Assman (see Psychrometer), speed of air movement - the anemometer or Cattermole (see), and radiation temperature - ball thermometer. After that, according to the results of measurements are the corresponding values of the effective temperature using nomograms or tables.
In scales efficient and effective temperatures overestimated the value of air humidity at low temperatures and undervalued at very high temperatures. On Ahlu (S. P. Yaglou), under normal residential and other premises in calm air readings dry bulb temperature are the best in the environment than the effective temperature or other composite index. In the presence of the sources of radiant heat or where the air temperature and wall (radiation temperature) differ considerably, the best indicator is the operational temperature, i.e. the index, showing the complex influence on the person of air temperature, radiation, temperature and air flow.
Scale effective temperature and the effective temperature are used during testing of the installation for air conditioning and heating of residential, public and medical premises, in health research, practice, industrial-sanitary supervision, the study of microclimate in the resorts, etc.