**6. Effect of H2 addition on the dynamic field and temperature**

#### **6.1 Longitudinal velocity field**

**Figure 9** shows the longitudinal velocity field for different percentages of hydrogen. By comparing the four fields, the potential cone for three configurations with the addition of hydrogen percentages (*α<sup>H</sup>*<sup>2</sup> ¼ 20%, 40% *and* 60%Þ are smaller than with pure methane. This indicates that the increase in velocity of the jet when adding hydrogen to the fuel reduces the size of the potential cone allowing the reactants to interact more effectively with oxygen and the ambient fluid. Note also that the addition of hydrogen reduces the height of the mixing area and consequently the flame height due to the high molecular diffusivity and low density of hydrogen promoting interaction between the jets more rapidly and the flow features to the behavior of a single jet.

methane with hydrogen promotes the increase of the flame temperature because the calorific value of this compound is much higher than that of methane. For example, the addition of 20% hydrogen increases the temperature 2500–3400 K (up to 900 K), and the addition of 60% hydrogen increases the temperature until

In this chapter, a new combustion technique in a burner with three separated jets is used. The idea of this burner consists of separating combustible and oxidant to dilute the reactants with combustion products before the mixing of the reactants. This type of burner has a great interest for the industry and the sizing of these burners requires a good understanding of the mechanisms controlling the stabiliza-

The Particle Image Velocimetry PIV is the technique used in experimental study in non-reacting flow and reacting flow inside the combustion chamber. The Reynolds Average Navier-Stokes (RANS) method is used in this numerical simulation

tion of the flame, the release of heat and the production of pollutants.

3700 K (1200 K more than in pure methane combustion).

*Radial profiles of the temperature for 0% H2, 20% H2, 40% H2 and 60% H2.*

*Longitudinal velocity field for 0% H2, 20% H2 and 40% H2.*

*A New Combustion Method in a Burner with Three Separate Jets*

*DOI: http://dx.doi.org/10.5772/intechopen.90571*

**7. Conclusion**

**27**

**Figure 10.**

**Figure 9.**

#### **6.2 Radial profiles of temperature**

**Figure 10** illustrates the radial temperature profiles for multiple hydrogen percentages in the fuel mixture. This figure shows that the substitution of a fraction of *A New Combustion Method in a Burner with Three Separate Jets DOI: http://dx.doi.org/10.5772/intechopen.90571*

**Figure 9.**

*Longitudinal velocity field for 0% H2, 20% H2 and 40% H2.*

**Figure 10.** *Radial profiles of the temperature for 0% H2, 20% H2, 40% H2 and 60% H2.*

methane with hydrogen promotes the increase of the flame temperature because the calorific value of this compound is much higher than that of methane. For example, the addition of 20% hydrogen increases the temperature 2500–3400 K (up to 900 K), and the addition of 60% hydrogen increases the temperature until 3700 K (1200 K more than in pure methane combustion).
