Cryogenic containers for sample storage use have their refrigeration principle, laboratory refrigerator refrigeration principle lies in the cooperation of electricity and refrigerant, liquid phase liquid nitrogen tank refrigeration principle is the perfect combination of liquid nitrogen and aerospace aluminum materials, vacuum adiabatic structure, directly immersed samples in -196 ℃ liquid nitrogen to achieve the purpose of refrigeration. What is the refrigeration principle of liquid nitrogen freezer in vapor phase?
The samples in a vapor phase liquid nitrogen freezer are neither immersed in liquid nitrogen nor electrically cooled, so how does it stay cold?
Actually, it’s still with the help of liquid nitrogen!
Cooling with a vacuum adiabatic structure consistent with a liquid phase liquid nitrogen container + liquid nitrogen!
However, vapor phase liquid nitrogen freezers use liquid nitrogen in an “indirect” manner, rather than directly “soaking” the sample with liquid nitrogen!
This is easier to understand from the point of view of its structure, liquid nitrogen freezers are not like conventional liquid nitrogen containers inside a single liner, its internal rotating tray with the help of the liner is divided into the upper and lower parts of the two parts of the upper part of the sample storage area, the lower part of the liquid nitrogen storage area, in the liquid nitrogen area is equipped with an evaporator, pay attention to the design of this is very important.
In the vapor phase liquid nitrogen freezer needs refrigeration, as a “refrigerant” exists in the liquid nitrogen, will be vaporized under the action of the evaporator part of the gasification, gasification and expansion of the volume of light, this part of the nitrogen will automatically rise to the sample of the storage area, rise to the top of the adiabatic cover plug cover, nitrogen will obediently stationed in the sample area, to play its refrigeration role.
“Indirectly with liquid nitrogen, directly with nitrogen, plus vacuum adiabatic structure escort”, this is the refrigeration principle of vapor phase liquid nitrogen freezers!