Turbulent axial flame temperatures

Finite Fire Sources Dimensionless Temperature, P x Continuous heat source, r0 = 9.,9 cm o Discontinuous heat source, r0 = 20 cm 

Note that the maximum flame temperature appears to be 800-900 °C for these scale fires. For larger scale fires, this flame temperature can increase with diameter e.g. for D 2m, 

This is consistent with the temperature measurements reported by Baum and McCaffrey [14], 

Application of Equation (10.37) gives a maximum value of the flame temperature rise corresponding to Xr = 0 as 

Maximum time averaged centerline temperature (°C) Fuel Ahc/s (kJ/g air) D (m) Q (kW) xr Source Cf,f 

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From these probability distributions, the mean temperature and the rms temperature are easily generated. They are displayed in Figures 3 and 4, respectively. The symmetry of the data is a result of reflecting the data through the axial centerline, i.e., data were collected on one side of the flame only. The main point of this paper is to illustrate the feasibility of obtaining temperature data in a turbulent diffusion flame. 

Several studies [23-25] have shown the effect of the combustor inlet conditions on the predicted flame structure, liner temperature, and emissions. These boundary conditions include the axial, tangential, and radial velocities the turbulent kinetic energy and associated length scale. To characterize the flow field at the exit of the TARS, two approaches were adopted. First, advanced diagnostic, such as LDV (discussed above), was used to measure the flow field distribution at the exit of the swirler. The data collected are used for inlet boundary conditions for the LES and database for numerical model validation. Second, a RANS model was used to study mixing and turbulence parameters in the TARS swirler [6]. 

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