It is very disturbing to read that you have only 223°C when considering the combustion at 1200°C. Please provide us the calculation note with all hypothesis and parameters and simulation results.It is understandable that RK has different temperature zones. According to my estimation/experiences, from 900°C to 1100°C, it could have about 50°C difference for the outers shell. It is very strange to have 100°C difference here. SUEZ should insist to get the calculation note.