Boyer, L
1994
Temperature Dissipation Measurements in a Lifted Turbulent Diffusion Flame
Boyer, L. and Queiroz, M.
Combustion Science and Technology, 79:1-34, 1991. Funded by ACERC.
Temperature dissipation measurements have been completed in a lifted turbulent non-premixed propane flame issuing from a converging nozzle at several axial stations and along the centerline. The radial and axial components of the temperature dissipation were measured directly. The assumption of log normality is shown to be a good approximation of the temperature dissipation character in the core of the flame out to ro, the radius where the mean temperature is at a maximum. Significant deviations from the lognormal distribution are observed on the outer side of the shear layer. The radial and axial components of the dissipation are reasonably isotropic in the region close to the jet's centerline. However, in direct contrast to the results found in nonreacting flows, detailed comparisons of the radial and axial temperature dissipation profiles in the off-axis region of 0.1 < r/ro < 1.3 indicate that there are definite anisotropic and non self-similar characteristics in the temperature dissipation. Furthermore, joint probability density functions between temperature and its dissipation components have shown that they are uncorrelated on axis, yet both negative and positive correlation existed further outward from ro at all the axial stations measured.
A Dual Thermocouple Probe for Measuring Temperature Dissipation Statistics in Reacting Flows
Dawson, R.W.; Boyer, L. and Queiroz, M.
Heat Transfer in Combustion Systems, 166:59-67, (R.J. Santoro and J.D. Felske, eds.), The American Society of Mechanical Engineers, 1991. Funded by ACERC.
This paper discusses the design of a dual thermocouple probe to measure temperature dissipation statistics in turbulent reacting flows. The probe is described in detail and an analysis is made of its advantages and accuracy, including a parametric study on the effect of wire spacing, sampling frequency, time constant, and cutoff frequency on the calculations of temperature dissipation statistics. Also, measurements performed with the probe in a partially premixed, lifted propane flame are briefly discussed to demonstrate the probe's capability. The measurements reported include mean and rms profiles and normalized probability density function of the lognormal radial component of temperature dissipation, as well as joint statistics between the temperature and its dissipation, represented by joint probability density functions.
Boyer, L
1994
Temperature Dissipation Measurements in a Lifted Turbulent Diffusion Flame
Boyer, L. and Queiroz, M.
Combustion Science and Technology, 79:1-34, 1991. Funded by ACERC.
Temperature dissipation measurements have been completed in a lifted turbulent non-premixed propane flame issuing from a converging nozzle at several axial stations and along the centerline. The radial and axial components of the temperature dissipation were measured directly. The assumption of log normality is shown to be a good approximation of the temperature dissipation character in the core of the flame out to ro, the radius where the mean temperature is at a maximum. Significant deviations from the lognormal distribution are observed on the outer side of the shear layer. The radial and axial components of the dissipation are reasonably isotropic in the region close to the jet's centerline. However, in direct contrast to the results found in nonreacting flows, detailed comparisons of the radial and axial temperature dissipation profiles in the off-axis region of 0.1 < r/ro < 1.3 indicate that there are definite anisotropic and non self-similar characteristics in the temperature dissipation. Furthermore, joint probability density functions between temperature and its dissipation components have shown that they are uncorrelated on axis, yet both negative and positive correlation existed further outward from ro at all the axial stations measured.
A Dual Thermocouple Probe for Measuring Temperature Dissipation Statistics in Reacting Flows
Dawson, R.W.; Boyer, L. and Queiroz, M.
Heat Transfer in Combustion Systems, 166:59-67, (R.J. Santoro and J.D. Felske, eds.), The American Society of Mechanical Engineers, 1991. Funded by ACERC.
This paper discusses the design of a dual thermocouple probe to measure temperature dissipation statistics in turbulent reacting flows. The probe is described in detail and an analysis is made of its advantages and accuracy, including a parametric study on the effect of wire spacing, sampling frequency, time constant, and cutoff frequency on the calculations of temperature dissipation statistics. Also, measurements performed with the probe in a partially premixed, lifted propane flame are briefly discussed to demonstrate the probe's capability. The measurements reported include mean and rms profiles and normalized probability density function of the lognormal radial component of temperature dissipation, as well as joint statistics between the temperature and its dissipation, represented by joint probability density functions.