Question

Meaning of Cavity Wall
What is cavity wall?

Answer 1

Cavity walls consist of two 'skins' separated by a hollow space (cavity).The skins are commonly masonry such as brick or concrete block. Masonry is an absorbent material, and therefore will slowly draw rainwater or even humidity into the wall, as well as from the inside of the house as from outside. The cavity serves as a way to drain water back out through weep holes at the base of the wall system or above windows. 

Answer 2

Answer:

(1) A cavity radiator is a block of material with intermal

cavity. The inner and outer surtaces of the block are

connected by a small hole. Most of the radiant

energy entering the block through the hole cannot

escape from the hole. The block, therefore, acts

almost like a blackbody.

(i) When the cavity radiator is heated to high tempera-

ture, radiation coming out from the hole resembles

blackbody radiation. It is called cavity radiation.

It depends only on the temperature of the radiator

and not on the shape and size of the cavity as well

as the material of the walls of the cavity