The Monte Carlo Ray-Trace Method in Radiation Heat Transfer and Applied Optics

J. Robert Mahan

• Publisher: Wiley-ASME Press Series
• Year: 2018
• ISBN:
  9781119518501
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Thermodynamics

A groundbreaking guide dedicated exclusively to the MCRT method in radiation heat transfer and applied optics

The Monte Carlo Ray-Trace Method in Radiation Heat Transfer and Applied Optics offers the most modern and up-to-date approach to radiation heat transfer modelling and performance evaluation of optical instruments. The Monte Carlo ray-trace (MCRT) method is based on the statistically predictable behavior of entities, called rays, which describe the paths followed by energy bundles as they are emitted, reflected, scattered, refracted, diffracted and ultimately absorbed.

The author – a noted expert on the subject – covers a wide variety of topics including the mathematics and statistics of ray tracing, the physics of thermal radiation, basic principles of geometrical and physical optics, radiant heat exchange among surfaces and within participating media, and the statistical evaluation of uncertainty of results obtained using the method. The book is a guide to help formulate and solve models that accurately describe the distribution of radiant energy in thermal and optical systems of practical engineering interest. This important guide:

• Combines radiation heat transfer and applied optics into a single discipline
• Covers the MCRT method, which has emerged as the dominant tool for radiation heat transfer modelling
• Helps readers to formulate and solve models that describe the distribution of radiant energy
• Features pages of color images and a wealth of line drawings

Written for faculty and graduate students in mechanical and aerospace engineering and applied optics professionals, The Monte Carlo Ray-Trace Method in Radiation Heat Transfer and Applied Optics is the first book dedicated exclusively to the MCRT method.

1
Fundamentals of Ray Tracing

A ray is defined as the collection of straight‐line path segments followed by an energy bundle from its point of emission to its point of absorption. The definition includes the possibility of intermediate reflection, scattering, refraction, and even diffraction events. Ray tracing involves the application of basic mathematics to the process of identifying the intersection of ray segments with surfaces. Most engineering and science students acquire the required mathematical tools long before they enter university. The current chapter provides a review of the mathematical principles governing ray tracing and the related issues of meshing and indexing.

1.1 Rays and Ray Segments

A ray is defined here as the continuous sequence of straight‐line paths connecting a point on one surface, from which an energy bundle is emitted, to a point on a second surface – or perhaps even on the same surface – where it is ultimately absorbed. One or several reflections from intervening surfaces may occur between emission and absorption of the energy bundle. The path followed by the energy bundle between reflections is referred to as a ray segment. Two situations are normally considered: either (i) the power of the emitted energy bundle does not change as it is reflected from one surface to the next until it reaches the surface where all its power is ultimately absorbed; or (ii) a fraction of the emitted power is left behind with each reflection until the remaining power is deemed to have dropped below a threshold value, at which point the ray trace is terminated. Both approaches have their adherents and are in common use, and both are developed in detail in this book.

1.2 The Enclosure

The enclosure is an essential concept in all approaches to radiation heat transfer analysis. We define the enclosure as an ensemble of surfaces, both real and imaginary, arranged in such a manner that a ray emitted into the interior of the enclosure cannot escape. Energy is conserved within the enclosure under this definition. If a ray does leave the enclosure through an opening, represented by an imaginary surface, the energy it carries is deducted from the overall energy balance.

1.3 Mathematical Preliminaries

Consider two points, P₀ and P₁, in three‐dimensional space...

Table of contents

• Cover
• Table of Contents
• Series Preface
• Preface
• Acknowledgments
• About the Companion Website
• 1 Fundamentals of Ray Tracing
• 2 Fundamentals of Thermal Radiation
• 3 The Radiation Distribution Factor for Diffuse‐Specular Gray Surfaces
• 4 Extension of the MCRT Method to Non‐Diffuse, Non‐Gray Enclosures
• 5 The MCRT Method for Participating Media
• 6 Extension of the MCRT Method to Physical Optics
• 7 Statistical Estimation of Uncertainty in the MCRT Method
• A
• Index
• End User License Agreement