Condensation heat transfer transient measurement device and method based on thermochromic liquid crystals

Abstract

The invention discloses a condensation heat transfer transient measurement device and method based on thermochromic liquid crystals, which belong to the field of condensation experiment measurement. The measurement device comprises an environment cavity, a heat transfer measurement module and a data acquisition system, wherein the environment cavity provides a stable and visual steam condensationenvironment; the heat transfer measurement module is used for realizing transient non-intrusive measurement of condensation heat transfer and comprises a test surface, a back thermochromic liquid crystal coating, a side thermochromic liquid crystal coating, a transparent cold conduction block, a transparent water cooling plate, a transparent heat insulation layer and a cooling water heat insulation layer; and the data acquisition system is used for acquiring, recording and analyzing images and data. According to the device, the transient temperature distribution of the transparent cold conduction block and the test surface is obtained through the color development change of the thermochromic liquid crystal coatings in the condensation process, then the condensation heat flux density and the supercooling degree are calculated, and quantitative analysis and visualization can be conducted on the average or local condensation heat transfer transient characteristics on the surfaces of different working conditions and different characteristics.

Description

technical field [0001] The invention relates to a condensation heat transfer transient measurement device and method based on thermochromic liquid crystals, belonging to the field of condensation experiment measurement. Background technique [0002] Condensation heat transfer of steam is a common phase change heat transfer process in industry. Enhancing steam condensation heat transfer can realize energy saving and emission reduction, and reduce resource consumption. Regulating the physical and chemical properties of the condensation surface is an important way to enhance condensation heat transfer. In order to study the condensation heat transfer performance (condensation heat transfer coefficient or heat flux) of different surfaces under different working conditions, it is necessary to build a stable and reliable condensation heat transfer system. Thermal testing device. [0003] The common condensation heat transfer test devices in the current research are mainly aimed ...

AI Technical Summary

Problems solved by technology

Different from the traditional hydrophobic surface, the condensed droplets on the superhydrophobic surface have the characteristics of small detachment radius, high detachment frequency, variable growth mode, and complex dynamic behavior. Study on the Influence of Condensation Heat Transfer Performance

In addition, the above two test devices generally have the problem of large errors in calculating the condensation heat transfer coefficient for low heat flux conditions (such as low-pressure steam condensation, steam condensation with non-condensable gas, etc.)

Images