This paper presents a method(F method)for determining the optical constants and the thicknesses of semi- transparent thin films.It has the following distinctive features:high precision;rapid determination of the measu...This paper presents a method(F method)for determining the optical constants and the thicknesses of semi- transparent thin films.It has the following distinctive features:high precision;rapid determination of the measured quantities;wide range of convergence of solutions;capable of judging whether or not the results are reasonable.In order to meet the needs of application and engineering design,a family of curves designated Fig.n-F was prepared.Using it n,k,d of the films can be conveniently and accurately determined.From the optical constants and the thicknesses of the films determined by the F method,all important thermal radiation properties of the semi-transparent films needed in application can be obtained.展开更多
A simplified technique is described for calculating the heat loss coefficient from the absorber of the solar flat-plate collector with a combined honeycomb.The problem is treated in two ways:the coupled mode and the d...A simplified technique is described for calculating the heat loss coefficient from the absorber of the solar flat-plate collector with a combined honeycomb.The problem is treated in two ways:the coupled mode and the decoupled mode.In the analysis,the cell wall and glass cover are assumed to be specularly reflecting and diffusely emitting surfaces,while the absorber is a diffusely reflecting and emitting surface.The influences of emissivities of the absorber and the cell wall as well as the aspect ratio on the heat loss coefficient are predicted.The theoretical results are compared with experimental data reported in the literature,and the agreement is good.展开更多
文摘This paper presents a method(F method)for determining the optical constants and the thicknesses of semi- transparent thin films.It has the following distinctive features:high precision;rapid determination of the measured quantities;wide range of convergence of solutions;capable of judging whether or not the results are reasonable.In order to meet the needs of application and engineering design,a family of curves designated Fig.n-F was prepared.Using it n,k,d of the films can be conveniently and accurately determined.From the optical constants and the thicknesses of the films determined by the F method,all important thermal radiation properties of the semi-transparent films needed in application can be obtained.
基金supported by the National Natural Science Foundation of China
文摘A simplified technique is described for calculating the heat loss coefficient from the absorber of the solar flat-plate collector with a combined honeycomb.The problem is treated in two ways:the coupled mode and the decoupled mode.In the analysis,the cell wall and glass cover are assumed to be specularly reflecting and diffusely emitting surfaces,while the absorber is a diffusely reflecting and emitting surface.The influences of emissivities of the absorber and the cell wall as well as the aspect ratio on the heat loss coefficient are predicted.The theoretical results are compared with experimental data reported in the literature,and the agreement is good.
