The paper presents a theoretical study about turbulent film boiling on a horizontal tube with external flowing liquid. The high velocity flowing liquid is determined by potential flow theory. By using Colburn analogy,...The paper presents a theoretical study about turbulent film boiling on a horizontal tube with external flowing liquid. The high velocity flowing liquid is determined by potential flow theory. By using Colburn analogy, the present paper successfully addresses a new model to predict the vapor-liquid interfacial shear, applies the interfacial shear into the forced balance equation and then combines the forced balance equation, the energy equation and thermal energy balance equation. At last, both the film thickness and Nusselt number can be obtained. Besides, the present analysis also includes radiation effects, temperature ratio and eddy diffusivity. Finally, a comparison between the results of the present study and those reported in previous theoretical and experimental studies is provided.展开更多
In the investigation, the complex geometric domain is a concave geometrical pattern. Due to the symmetric character, the left side of the geometric pattern,?i.e.?the L-shaped region is calculated in the study. The gov...In the investigation, the complex geometric domain is a concave geometrical pattern. Due to the symmetric character, the left side of the geometric pattern,?i.e.?the L-shaped region is calculated in the study. The governing equation is expressed with?Laplace?equations. And the analysis is solved by eigenfunction expansion and point-match method. Besides, visual?C++?helps obtain the results of numerical calculation. The local values and the mean values of the function are also discussed in this study.展开更多
Film boiling on a horizontal elliptical tube immersed in external flowing nitrogen liquid is investigated in the present paper. The isothermal wall temperature is high enough to induce turbulent film boiling, and then...Film boiling on a horizontal elliptical tube immersed in external flowing nitrogen liquid is investigated in the present paper. The isothermal wall temperature is high enough to induce turbulent film boiling, and then a continuous vapor film runs upward over the surface. The high velocity of the flowing saturated liquid at the boundary layer is determined by potential flow theory. In addition, the present paper addresses a new model to predict the vapor-liquid interfacial shear on an elliptical tube under forced convection turbulent film boiling. In the results, film thickness and Nusselt number can be obtained under different eccentricity and Froude number. And a comparison between the results of the present study and those reported in previous experimental studies is provided. The results show that there is a good agreement between the present paper and the experimental data.展开更多
文摘The paper presents a theoretical study about turbulent film boiling on a horizontal tube with external flowing liquid. The high velocity flowing liquid is determined by potential flow theory. By using Colburn analogy, the present paper successfully addresses a new model to predict the vapor-liquid interfacial shear, applies the interfacial shear into the forced balance equation and then combines the forced balance equation, the energy equation and thermal energy balance equation. At last, both the film thickness and Nusselt number can be obtained. Besides, the present analysis also includes radiation effects, temperature ratio and eddy diffusivity. Finally, a comparison between the results of the present study and those reported in previous theoretical and experimental studies is provided.
文摘In the investigation, the complex geometric domain is a concave geometrical pattern. Due to the symmetric character, the left side of the geometric pattern,?i.e.?the L-shaped region is calculated in the study. The governing equation is expressed with?Laplace?equations. And the analysis is solved by eigenfunction expansion and point-match method. Besides, visual?C++?helps obtain the results of numerical calculation. The local values and the mean values of the function are also discussed in this study.
文摘Film boiling on a horizontal elliptical tube immersed in external flowing nitrogen liquid is investigated in the present paper. The isothermal wall temperature is high enough to induce turbulent film boiling, and then a continuous vapor film runs upward over the surface. The high velocity of the flowing saturated liquid at the boundary layer is determined by potential flow theory. In addition, the present paper addresses a new model to predict the vapor-liquid interfacial shear on an elliptical tube under forced convection turbulent film boiling. In the results, film thickness and Nusselt number can be obtained under different eccentricity and Froude number. And a comparison between the results of the present study and those reported in previous experimental studies is provided. The results show that there is a good agreement between the present paper and the experimental data.
