•  Viewfactor
  •  Introduction
    • 1.1 About the Viewfactor Program
    • 1.2 Features and Benefits
    • 1.3 About this Guide
    •  1.4 Using this Guide
      • Assumptions About the User
      • Other Pertinent Documents
    • 1.5 Guide Organization
    • 1.6 Overview of Viewfactor Analysis
    •  1.7 Nomenclature
      • Conventions
      • Units
  •  Overview
    • 2.1 Purpose
    •  2.2 Relationship of Viewfactor to Patran and Patran Thermal
      • Description
    •  2.3 Viewfactor Data and Program Flow
      • Description
    •  2.4 Summary of the Analysis Cycle for a Thermal Radiation Problem
      • Problem Definition
      • General Preprocessing
      • General Patran Thermal Preparation
      • Thermal Radiation Specific Preprocessing
      • Preparation for Viewfactor Analysis
      • Viewfactor Analysis
      • Post Viewfactor Analysis
      • Patran Thermal Analysis
      • Postprocessing
      • Refinements
  •  Model Creation for a Thermal Radiation Problem
    • 3.1 Purpose
    •  3.2 Radiation Enclosure Concept
      • Definition of Enclosure
      • The Enclosure ID
      • Wavebands and Enclosures
      • list2+s of the Use of Enclosures
    •  3.3 Surface Orientation in Patran
      • The Importance of Surface Orientation
      • Determining Surface Orientation
      • Correcting Improper Surface Orientations
      • Suggested Practices for Creating Properly Oriented Surfaces
    •  3.4 Specifying Radiation Boundary Conditions Using Patran Reference Manual (VFAC Boundary Condition)
      • Purpose of the Viewfactor Form
      • Form for the VFAC LBC
      • Requirement for Oriented 2-D Surfaces Related to the VFAC LBC
      • Neutral File Data Packet Created from the VFAC LBC
    •  3.5 Advanced Features of the VFAC Boundary Condition
      • Referencing Participating Media Radiation Nodes
      • Referencing Ambient or Space Radiation Nodes
      • Identifying a Surface as Being Convex
      • Identifying a Surface as Not Obstructing the View Between Other Surface Pairs
    • 3.6 Relationship of VFAC LBC Data to VFINDAT File Data
    •  3.7 Patran Thermal TEMPLATEDAT Files for Surface Property Description
      • Thermal Radiation Wavebands as Used in MSC Patran Thermal User’s Guide
      • Radiation Resistor Types Used in Patran Thermal
      • Patran Thermal MPIDs (Material Property IDs)
      • Patran Thermal Material Property Definition
      • VFAC Template Format
      • Examples of TEMPLATEDAT Files for Thermal Radiation
    •  3.8 Compatibility Requirements for Model and VFAC Templates
      • Origin of the Problem
      • Suggested Procedures to Avoid Compatibility Problems
    •  3.9 Symmetry as Applied to the Model and Viewfactor Radiation Exchange
      • The Purpose of Symmetry in Viewfactor
      • Caveats Concerning the Use of Symmetry in Thermal Radiation Modeling
      • Symmetry Operations Supported in Viewfactor
      • list2+ of the Use of Symmetry in Thermal Radiation Modeling
      • list2+ Which Appears Symmetric, But in Fact Is Not Symmetric
      • Entering Viewfactor Symmetry Operations in the Patran Model
  •  Preparation for Analysis
    • 4.1 Introduction
    • 4.2 Viewfactor Execution From Patran Thermal
    •  4.3 PATQ Translation from the Patran Neutral File to the VFINDAT File
      • Spawning From Patran vs. Stand-Alone Execution
      • Step-by-Step Procedure (Stand-Alone Execution)
    •  4.4 VFCTL, the Viewfactor Program Execution Control File
      • Philosophy and Structure of the VFCTL File
      • Keywords in the VFCTL File
  •  Analysis
    •  5.1 Submitting a Viewfactor Job for Analysis
      • Review the Viewfactor Control/Parameters
      • Review Directory for Required Files
      • The Viewfactor Command Line
    •  5.2 Output Created by a Viewfactor Execution
      • VFMSG
      • VFDIAG
      • VFRAWDAT
      • VFRESDAT
      • VFNODEDAT
    •  5.3 Reviewing the Viewfactor Output
      • VFMSG, the Viewfactor Message File
      • VFDIAG, the Viewfactor Diagnostic Data File
  •  Post-Analysis
    • 6.1 Introduction
    •  6.2 Interface From Viewfactor to Patran Thermal
      • Viewfactor VFRESDAT and VFNODEDAT Files as Input to Patran Thermal’s QTRAN
      • Translating Binary Resistor File VFRESDAT to a Text File, VFRESTXT
    • 6.3 noteplains on Resistor Values
    • 6.4 THERMAL Analysis
    • 6.5 THERMAL Results Postprocessing
  •  Changing the Surface Template Data After Viewfactors are Calculated
    • 7.1 Introduction
    • 7.2 Compatible VFAC LBC and Template Data
    •  7.3 New Resistors from Raw Viewfactor Data
      • Changing TEMPLATEDAT VFAC Templates
      • Changing Patran Thermal Material Definitions
      • Changing VFCTL
      • Submitting the New Viewfactor Job
  •  Theory and Computational Limitations
    • 8.1 Introduction
    • 8.2 Viewfactor
    • 8.3 Mean Beam Length
    • 8.4 Obstructions
    •  8.5 Computational Limitations
      • Grazing Incidence of the Intersurface Ray with the Surface
      • Spatial Resolution
      • Extreme Scales
  •  Data File Specifications
    • 9.1 Introduction
    •  9.2 VFINDAT (Input Data File)
      • Examples
      • Detailed Descriptions
    • 9.3 VFRAWDAT (Raw Viewfactor Data)
    • 9.4 VFRESDAT (Resistor Data)
    •  9.5 VFDIAG (Diagnostic Data)
      • Introduction
      • Examples
      • Detailed Descriptions
    • 9.6 TEMPLATEDAT (Surface Pointer Data)
    • 9.7 VFNODEDAT (Radiosity Node Lists)
  •  Rules for Radiation Resistors
    • 10.1 Introduction
    • 10.2 General Rules for Radiation Resistors
    • 10.3 Rules for Emissivity Resistors
    • 10.4 Rules for Radiosity Resistors
  •  Typical Errors and Probable Causes for Viewfactor Errors
    • A.1 Purpose
  •  Quick Reference Guide to Viewfactor
    • B.1 Purpose
  •  Memory Requirements for Viewfactor Execution
    • C.1 Purpose
  •  Machine-Specific File Names for Viewfactor
    • D.1 Purpose
  •  Example Thermal Radiation Problems
    • E.1 Purpose
    •  E.2 Problem 1 - Steady-State Radiative Boundary Conditions
      • Objectives
      • Model Description
      • Exercise Procedure
    • E.3 Problem 2 - Parallel Semi-Infinite Plates
    • E.4 Problem 3 - Heated Reaction Chamber

Viewfactor

Problem 3 - Heated Reaction Chamber