Radiation heating and drying include infrared ray, ultraviolet ray, microwave/radio frequency, electron beam and laser, etc. Infrared ray heating and drying is to use the principle of electromagnetic radiation heat transfer in a direct way to achieve the purpose of heating and drying objects, so as to avoid heat transfer media。
Radiation heating and drying of infrared, ultraviolet, microwave/rf, electron beam and laser, etc., the principle of infrared heating drying is the use of electromagnetic radiation heat transfer, heat transfer indirect way and achieve the purpose of heating drying object, avoiding energy loss caused by heat transfer media, infrared due to produce easily at the same time, good controllability fund and other characteristics, heat quickly, short drying time and improve productivity, product quality improvement and equipment space saving, etc Infrared wavelength range is roughly 0.75 nm to 1000 nm, It gets its name from the fact that its wavelength is outside the red light wavelength (about 0.6nm to 0.75nm).In less than 2000 ℃, within the limits of conventional industrial thermal infrared is the main thermal radiation. So, how does infrared heating work? What are the advantages?
People sometimes divide infrared ray into "near infrared", "medium infrared", "far infrared" and so on a number of small areas, the so-called far, medium, near, it is to point to its relative distance from the red light in the electromagnetic spectrum. Whether the infrared heating is effective depends on the absorption degree of the heated object. The higher the absorption rate, the better the infrared radiation effect. The absorption rate depends on the type of material being heated, the surface state, the wavelength of the infrared radiation source, etc. The ratio of radiant energy reflected by the matter of incident energy is called reflectance. The ratio of radiation energy of material to incident energy is called penetration rate, which varies with the properties and thickness of the material. The effective penetration range of different materials is also different. The penetration rate of non-transparent materials is usually regarded as zero. Generally, metal crystals are very dense, and electromagnetic radiation through the surface can decay rapidly within a very short distance, so the penetration depth of thermal radiation on metal is on the order of micrometers. And not very dense molecular structure of nonmetallic materials, non-metallic material at room temperature under different respectively has the characteristics of the vibration frequency, so when the incident electromagnetic wave arrived at interface, the electromagnetic wave is seldom reflection, through the interface more easily into the surface, some has resonance into heat, some can't arouse resonance by refraction, scattering and reflection. Because the actual object is not a simple material with a single structure, some radiation waves that are not absorbed by the surface layer will be absorbed to varying degrees by the resonance of other substances in the process of penetration. The unbroken portion of the radiation energy can only be transmitted through the entire thickness. Therefore, the penetration depth of non-metal is higher than that of metal.
Infrared heating advantages and efficiency. In recent years, infrared drying and heating methods have been accepted at an alarming rate and have been used at various levels. The main advantages of infrared drying methods are as follows: it has the penetration power and can be heated both inside and outside at the same time. No. heat transfer medium is required, thermal efficiency is good. Can be locally heated to save energy. Provide a comfortable working environment. Save the construction cost and space of the furnace body. Clean heating process. The temperature control is easy, and the temperature rises rapidly, and it is safe. Low thermal inertia, no need to warm up the machine, save manpower. Because infrared heating has the above advantages, it is possible to obtain high efficiency, high uniformity and high-quality products. Above are the infrared heating principle and its advantages related to the introduction.