View Factor - View Factors of Differential Areas

View Factors of Differential Areas

Taking the limit of a small flat surface gives differential areas, the view factor of two differential areas of areas and at a distance S is given by:

F_{1 \rarr 2} = \frac{\cos\theta_1 \cos\theta_2}{\pi S^2}\hbox{d}A_2

where and are the angle between the surface normals and a ray between the two differential areas.

The view factor from a general surface to another general surface is given by:

F_{1 \rarr 2} = \frac{1}{A_1} \int_{A_1} \int_{A_2} \frac{\cos\theta_1 \cos\theta_2}{\pi S^2}\, \hbox{d}A_2\, \hbox{d}A_1


The view factor is related to the etendue.

Read more about this topic:  View Factor

Famous quotes containing the words view, factors, differential and/or areas:

    “Thy fair virtue’s force perforce doth move me
    On the first view to say, to swear, I love thee.”
    —William Shakespeare (1564–1616)

    “Language makes it possible for a child to incorporate his parents’ verbal prohibitions, to make them part of himself....We don’t speak of a conscience yet in the child who is just acquiring language, but we can see very clearly how language plays an indispensable role in the formation of conscience. In fact, the moral achievement of man, the whole complex of factors that go into the organization of conscience is very largely based upon language.”
    —Selma H. Fraiberg (20th century)

    “But how is one to make a scientist understand that there is something unalterably deranged about differential calculus, quantum theory, or the obscene and so inanely liturgical ordeals of the precession of the equinoxes.”
    —Antonin Artaud (1896–1948)

    “Adults understandably assume that the level of verbal proficiency a five-year-old displays represents his level of proficiency in all areas of functioning—if he talks like an adult, he must think and feel like one. However, five-year-olds,... belie the promise of adult-like behavior with their child-like, impulsive actions.”
    —Dorothy H. Cohen (20th century)