The heat transfer in the Principles of Chemical Engineering course is about mastering process analysis and engineering methods for each process. Convective heat transfer does not have to be understood narrowly as circulation;Convection is also present when the fluid flows laminar in a circular tube. The existence of convection causes the problem of two-dimensional heat transfer in the radial and axial directions, but in engineering treatment, it is still expressed as one-dimensional heat transfer, that is, the convection in the axial direction is artificially superimposed on the radial direction. It is necessary to prevent this formal treatment from obscuring the actual mechanism. The analysis of the heat transfer process is to understand the controlling factors of heat transfer in each process, so as to clarify the intention of various enhanced heat transfer methodsBy linking process analysis to the empirical formulas of each process, the empirical formulas do not become boring and irrational, but rather a test of the degree of understanding of the mechanism. In the teaching of the heat transfer chapter, we can make full use of various heat transfer processes and different research and treatment methods selected in different situations. Clarify the approach to the study**. For radiative heat transfer between solids, a direct theoretical derivation method is adoptedFor the heat transfer of condensation, the model method is adopted;The convective heat transfer without phase change is treated by similarity theory or factor analysisFor boiling heat transfer, only pure empirical treatment can be used.
The device function device can observe the flow state of fluid water in the rising film evaporator (bubble flow, elastic flow, stirred flow and annular flow). Measure the convective heat transfer coefficient and the dryness of steam under different flow patterns. Turn the page in 2023