5 inch gauge Boiler Combustion

1. Boiler Combustion (Simplified) Coal Fired MODEL LOCOMOTIVES

3. Solid Fuel (Coal)

9. Primary Air Secondary Air Primary Air Fire Box Air intake in fire box Blast nozzle blower ring

14. Hydrocarbons 1200 º Carbon Dioxide Carbon Monoxide Damper Lever Front damper Rear damper Ash Air Oxygen and Nitrogen At 60 º F Carbon Dioxide Water Vapour Nitrogen 2000 ºF Ash pan Air Oxygen and Nitrogen 700 ºF Blast Nozzle Blower Ring Coal - Carbon - Hydrogen + Ash Complete combustion of the coal at high temperatures upwards of 2000 ºF Gasses cool down on passage through tubes EXOTHERMIC REACTION Fire hole door partially open Incandescent fire bed

15. Incomplete combustion showing miss management of the fire Air- Oxygen and Nitrogen at 60 ºF Fire hole door fully open Holes in the fire bed Drop in fire box temperature Uneven thick fire bed Heat losses up to 70 % Clinker grate area reduced impeding draft

16. Deflector plate Stainless steel arch Promotes combustion absorbs the heat from the volatile gasses before being discharged reduces temperature drop Directs the path of air Other uses' of absorbing heat Volatile gasses

17. Combustion chamber Shortened tube length improved heat transfer Volatile gases Combustion chamber Larger heating service