Analytical Heat Transfer Analysis under Boundary Conditions of the Fourth Kind (Conjugate)

2016 ◽  
Vol 5 (2) ◽  
pp. 65-84
Author(s):  
Abram Dorfman
Keyword(s):  
Heat Transfer ◽  
Boundary Conditions ◽  
Heat Transfer Analysis ◽  
Fourth Kind

Heat Transfer Predictions of Film Cooled Stationary Turbine Airfoils

2007 ◽  
Author(s):  
Gregory M. Laskowski ◽  
Anil K. Tolpadi ◽  
Michael C. Ostrowski
Keyword(s):  
Heat Transfer ◽  
Boundary Conditions ◽  
Turbine Blade ◽  
Film Cooling ◽  
Internal Flow ◽  
External Flow ◽  
Heat Transfer Analysis ◽  
Hot Gas ◽  
Turbine Airfoils ◽  
Film Cooling Holes

Conventional heat transfer design methods for high temperature gas turbine airfoils decouple the internal and external flow. Thermal boundary conditions from these decoupled analyses are applied to the blade surfaces to predict turbine life. Typically, the domain for the external flow includes the hot gas path and the film cooling holes while the domain for the internal flow includes the internal flow passages and film cooling holes. The solid blade itself couples the external and internal flow and heat transfer. Since film cooling flow physics can play a significant role on the overall turbine blade heat transfer, there has been increased interest in capturing these effects by including the hole geometry in the solution procedure. Ideally, the complete turbine blade heat transfer analysis would be provided by efficient CFD simulations for the coupled problem including the internal passages, film cooling holes and hot gas path. By prescribing both the external flow and internal flow inflow/outflow boundary conditions, the hole physics can be included in the solution. The current paper presents results obtained for coupled simulations of the NASA C3X vane and VKI rotor which models the internal passages, hole geometries and hot gas path. In both cases, cooling is achieved by rows of pressure-side, leading-edge and suction-side film cooling holes. The rows are independently fed by span-wise, constant area plenums. The former has a total of 152 cylindrical cooling holes whereas the later has a total of 110 cylindrical/shaped holes. In addition, the C3X vane consists of 10 internal radial cooling passages of cylindrical cross-section. The simulations were conducted with the Shear Stress Transport (SST) model on a grid that extended into the viscous sub-layer along all surfaces. The computed surface pressure and external heat transfer coefficient distributions at mid-span are compared to experimental data for both cases. Internal heat transfer predictions are also presented and discussed.

Considerations in the Design and Analysis of an ASME Section VIII, Div. 2 Reactor Support Skirt

2007 ◽  
Vol 129 (2) ◽  
pp. 316-322
Author(s):  
Dennis K. Williams ◽  
Trevor G. Seipp
Keyword(s):  
Heat Transfer ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Series Representation ◽  
Base Plate ◽  
Reactor Vessel ◽  
Heat Transfer Analysis ◽  
Element Analysis ◽  
Section Viii

This paper describes the considerations employed in the finite element analysis of a relatively “short” support skirt on a hydrocarbon reactor vessel. The analysis is accomplished in accordance with ASME B&PV Code, Section VIII, Division 2 alternate rules in conjunction with the guidelines outlined in WRC Bulletin 429. This provides a sound basis for the classification of the calculated stress intensities. The support skirt is capable of sustaining the deadweight load in addition to resisting the effects of thermal displacements, wind loadings, overturning moments from external piping loads on the attached hydrocarbon reactor vessel, and friction between the skirt base plate and concrete foundation. The displacement and thermal boundary conditions are well defined and discussed in detail. The effects of multiple scenarios for the displacement boundary conditions are examined. The skirt design also employs a hot-box arrangement whereby the primary mode of heat transfer is by radiation. A discussion of the two-part analysis is included and details the interaction between the heat transfer analysis and the subsequent structural analysis. The heat transfer finite element analysis is utilized to determine the temperatures throughout the bottom of the vessel shell and head, as well as the integrally attached support skirt. Of prime importance during the analysis is the axial thermal gradient present in the skirt from the base plate up to and slightly beyond the skirt-to-shell junction. While the geometry of the subject vessel and skirt is best described as axisymmetric, the imposed loadings are a mixture of axisymmetric and non-axisymmetric. This combination lends itself to the judicious selection and utilization of the harmonic finite element and properly chosen Fourier series representation of the applied loads. Comparison of the thermally induced axial stress gradient results from the FEA to those obtained by the closed form beam-on-elastic-foundation are also tendered and discussed. Finally, recommendations are included for the design and analysis of critical support skirts for large, heavy-wall vessels.

Considerations in the Design and Analysis of an ASME Section VIII, Div. 2 Reactor Support Skirt

2003 ◽  
Author(s):  
Dennis K. Williams ◽  
Trevor G. Seipp
Keyword(s):  
Heat Transfer ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Series Representation ◽  
Base Plate ◽  
Reactor Vessel ◽  
Heat Transfer Analysis ◽  
Element Analysis ◽  
Section Viii

This paper describes the considerations employed in the finite element analysis of a relatively “short” support skirt on a hydrocarbon reactor vessel. The analysis is accomplished in accordance with ASME B&PV Code, Section VIII, Division 2 alternate rules in conjunction with the guidelines outlined in WRC Bulletin 429. This provides a sound basis for the classification of the calculated stress intensities. The support skirt is capable of sustaining the deadweight load in addition to resisting the effects of thermal displacements, wind loadings, overturning moments from external piping loads on the attached hydrocarbon reactor vessel, and friction between the skirt base plate and concrete foundation. The displacement and thermal boundary conditions are well defined and discussed in detail. The effects of multiple scenarios for the displacement boundary conditions are examined. The skirt design also employs a hot-box arrangement whereby the primary mode of heat transfer is by radiation. A discussion of the two-part analysis is included and details the interaction between the heat transfer analysis and the subsequent structural analysis. The heat transfer finite element analysis is utilized to determine the temperatures throughout the bottom of the vessel shell and head, as well as the integrally attached support skirt. Of prime importance during the analysis is the axial thermal gradient present in the skirt from the base plate up to and slightly beyond the skirt-to-shell junction. While the geometry of the subject vessel and skirt is best described as axisymmetric, the imposed loadings are a mixture of axisymmetric and non-axisymmetric. This combination lends itself to the judicious selection and utilization of the harmonic finite element and properly chosen Fourier series representation of the applied loads. Comparison of the thermally induced axial stress gradient results from the FEA to those obtained by the closed form beam-on-elastic-foundation are also tendered and discussed. Finally, recommendations are included for the design and analysis of critical support skirts for large, heavy-wall vessels.

scholarly journals Heat transfer analysis of a second grade fluid over a stretching sheet

1995 ◽  
Vol 18 (4) ◽  
pp. 765-772 ◽  
Author(s):  
C. E. Maneschy ◽  
M. Massoudi
Keyword(s):  
Heat Transfer ◽  
Boundary Conditions ◽  
Newtonian Fluid ◽  
Stretching Sheet ◽  
Heat Transfer Analysis ◽  
Second Grade ◽  
Temperature Profiles ◽  
Second Grade Fluid ◽  
Grade Fluid

The heat tranfer and flow of a non-Newtonian fluid past a stretching sheet is analyzed in this paper. Results in a non-dimensional form are presented here for the velocity and temperature profiles assuming different kind of boundary conditions.

Sign in / Sign up

Export Citation Format

Share Document