Answer to Question #326119 in Mechanical Engineering for ni12

Question

A boiler uses 18 kg air per kg of fuel. Determine the minimum height of

chimney required to produce a draught of 25 mm of water. The mean

temperature of chimney gases is 335° C and that of outside air 22° C.

Answer 1

T₂ = 335°C = 335 + 273 = 608 K; 

T₁ = 22°C = 22 +273 = 295 K; m = 18 kg;

h = 25 mm

Solution

h = 353 H ( 1/T₁ - (m+1/mT₂)

25 = 353 H ( 1/295 - (18+1)/18*608)

H = 42.83 mm minimum height of chimney