HEAT BALANCE SHEET

A heat balance sheet is an account of heat supplied and heat utilised during engine trial.

1. Heat supplied to the engine,Q_s = ṁ_f × LCVwhere ṁ_f = mass of fuel supplied per hour.LCV lower calorific value of fuel, kJ/kg
2. Heat utilised in various ways:
   1. Heat equivalent of BP,Q₁ = 3600 × BP in kW kJ/h
   2. Heat carried away by cooling water,Q₂ = ṁ_w ⋅ c_pw (T_w0 − T_wi) kJ/h
   3. Heat carried away by exhaust gases,Q₃ = ṁ_g ⋅ c_pg (T_ge − T_a) kJ/h
   4. Heat unaccounted for,Q₄ = Q_s − (Q₁ + Q₂ + Q₃)