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Hi guys! I am mechanical engineer and I make an article about the subject of my thesis. I have designed two pumps for LH2 and LO2 in my thesis and I want to design the turbine in order to add it in the article. I have calculated the power (Kw) of the turbine including the hydraulic losses of the pumps, the turbine and the mechanical losses of the gearbox. General, I can adjust all variables automatically by excel in case of false . But I face a problem about the way of calculating enthalpy(h), temperature(T), specific heat capacity (Cp,Cv), pressure(P), kinematic viscosity(v), thermal conductivity(λ), the ration γ and density (ρ) of exhaust gases in pre-burner. The cycle of rocket engine is open cycle with gas generator (pre-burner). I have set a small amount of fuel to burn with excess oxygen. The amount of hydrogen is adjusted based on the power of the tourbine and the amount of oxygen is adjusted manually. Below is the chemical equation for pre-burner combustion: xH2 +((x/2)+y)O2 -> xH2O + yO2. What formulas and parameters should I put in excel to automatically calculate the sizes (h,Cp,v,T,P....) after combustion in pre-burner? I have found some formulas of NASA for combustion LH2/LO2 but for burner LRE , not pre-burner. Also I don't know if I should put and others parametres for examble production of other products (Η2Ο2). I haven't designed the pre-burner yet. I am just designing the turbopump system and I want to start the design of the turbine with a predetermined mixture of exhaust gases at the inlet. A solution I found recently are some NASA curves that calculate the Cp/R ratio for a certain temperature. This way I can also calculate the rest of the quantities with sums and averages. But I don't know if this approach is correct because I will start with an inlet temperature and make calculations assuming ideal combustion. Should I do it with an energy balance? Can anyone guide me or help me find additional formulas? Can any experienced researcher or professional on this field help me? The fluids are cryogenic state. Βelow the table with the properties of the fluids : properties LH2 LO2 ν(mm2/s) 0,22917 0,27 ρ(m3/kg) 73,723 1223 Τ(Κ) 18 73 Pv (Pa) (vapor pressure) 49204 10810 Cp (J/(kgK) 8514 1678 λ(W/mK) 0,10319 0,1753 CFD analysis results showed that I have a total pressure of 198bar for LH2 and 124,6bar for LO2 at the pump outlet.