What methods of measuring temperature thermometer?

First of all, what is the temperature? Temperature is representing the degree of cold and hot objects physical quantities, it is the most common in industrial production and scientific experiments, one of the final thermal parameter. Temperature measuring almost accounts for half of industrial thermal parameter measurement, considerably more than parameters such as pressure, flow, level measurement. Temperature cannot be directly measured, but only with the help of hot and cold heat exchange between different objects, and some physical properties of the object changes with different degree of cold and hot features, indirect measurement. Choose as a condition of temperature measuring material is: 1) Single value changes with temperature is continuous. 2) Is not affected by other factors. 3) Easy to more accurately. According to the temperature measurement method can be divided into contact measurement and non-contact temperature measuring two kinds big. 1. Non-contact temperature measuring any two objects of different degree of cold and hot contact, is bound to happen phenomenon of heat transfer, heat conduct by a high degree of heated objects to the low degree of heated objects, until the degree of hotness or coldness of two objects is consistent, namely reach thermal equilibrium state. Contact method of temperature measurement is to use the principle of choosing an object with the contact object to be tested, and heat exchange. When both reach thermal equilibrium state, select the object and the temperature of the object to be tested are equal, so, can choose by measuring the object of a physical quantity to get the temperature of the object to be tested. 2 non-contact measuring WenFei contact temperature measurement at present in industry is given priority to with radiant temperature measurement, it is the feature of any part of the temperature measuring element are not contact with that object to be tested, but through the measured object and thermal radiation effect between thermal element to realize temperature measuring, and therefore won't destroy the temperature field of the object under test, not only can measure the temperature of the moving or rotating objects, and can be measured by the method of scanning the temperature distribution on the surface of the object. Reflect the fast, temperature measuring range is very light, in principle is not limited by temperature limit, usually used to measure 1000 & deg; C more move, rotate or reaction temperature of high temperature object rapidly, but the influence of some factors, so the temperature measurement accuracy is generally not high.