Temperature measurement of axisymmetric flames under the influence of magnetic field using Talbot interferometry (original) (raw)
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Optics and Lasers in Engineering, 2015
The effect of magnetic field on temperature and temperature profile of diffusion flame is investigated by using circular grating Talbot interferometer. Talbot interferometric fringes are recorded for diffusion flame generated by butane torch burner, in the absence of magnetic field, in the presence of uniform magnetic field, upward-decreasing and upward-increasing magnetic field. Analysis of recorded interferogram reveals that the temperature of the flame is increased under the influence of the upwarddecreasing magnetic field and flame temperature is decreased under the influence of upward-increasing magnetic field. Uniform magnetic field has a negligible effect on temperature of the flame.
Optics and Lasers in Engineering, 2018
This paper presents the effect of magnetic field (upward decreasing, uniform and upward increasing) on wick stabilized micro diffusion flame by using digital holographic interferometry (DHI). The investigations reveal that under the influence of upward decreasing and uniform magnetic field temperature inside the micro flame increases in comparison to temperature inside micro flame without magnetic field. This is in contrary to normal diffusion flame, where uniform magnetic field has a little or no effect on the temperature. DHI is inherently more accurate more precise and is having better spatial resolution. DHI is ideally suited to study micro flame.
Optik, 2018
In this paper an application of circular grating Talbot interferometer is investigated for measurement of temperature and temperature profile of micro flame under the influence of gradient and uniform magnetic field. Hilbert transform is used for phase extraction from a single Talbot interferometric fringe pattern. In addition to this a numerical study is undertaken to established the effect of magnetic field on flame flow characteristics such as flame length, fuel mass flow rate, magnetic susceptibility and mass fractions of oxygen which is the main oxidizer and products of combustion in candle flame is demonstrated. Experimental investigation reveals that the temperature of the flame is increased under the influence of the upward-decreasing magnetic field and decreased in upward-increasing magnetic field. In a uniform magnetic field the flame temperature is also increased, which is in contrast to the normal diffusion (large size) flame. The system is cost effective, easy to align, less prone to environmental perturbation and capable of measuring temperature of a large size (centimeter) flame to micro size (millimeter) flame.
Digital holographic interferometry for measurement of temperature in axisymmetric flames
Applied Optics, 2012
In this paper, experimental investigations and analysis is presented to measure the temperature and temperature profile of gaseous flames using lensless Fourier transform digital holographic interferometry. The evaluations of the experimental results give the accuracy, sensitivity, spatial resolution, and range of measurements to be well within the experimental limits. Details of the experimental results and analysis are presented.
SAE Technical Papers, 2004
Temperature distribution as the flame propagated and contacted to the wall of the combustion chamber was measured by real-time holographic interference method, which mainly consisted of an argon-ion laser and a highspeed video camera. The experiment was done with a constant volume chamber and propane-air mixture with several kinds of quivalence ratios. From the experimental results, it can be found that the temperature distribution outside the zone from the surface of the combustion chamber to 0.1mm distance could be measured by counting the number of the interference fringes, but couldn’t within this zone because of lacking in the resolution of the used optical system. The experimental results show that the temperature distribution when the heat flux on the wall increases rapidly and when the heat flux shows the maximum value are quite different by the equivalence ratio. Therefore, the temperature distribution when the heat flux shows the maximum is related with the lower temperature of ignition temperature.
Temperature measurement by holographic interferometry in liquids for transient flame spread
1994
This investigation developed a systematic method to measure the temperatures and the mass concentrations of local species in a nonpremixed ethylene-air flame using the holographic interferometry (HI) technique. A nearly linear state relationship between the Gladstone-Dale constant and the mixture fraction was deduced. Normalized state relationships between the refractive index and the mixture fraction were established from detailed combustion simulations for the NPFs. The maximum error of temperature caused by the assumption of composition of air was reduced from 48.84% to under 1.6% for the NPFs using the systematic method. The method can overcome the difficulty that the concentrations of local species must be known when measuring the temperature by HI for NPFs.
Fuel, 2007
This investigation developed a systematic method to measure the temperatures and the mass concentrations of local species in a nonpremixed ethylene-air flame using the holographic interferometry (HI) technique. A nearly linear state relationship between the Gladstone-Dale constant and the mixture fraction was deduced. Normalized state relationships between the refractive index and the mixture fraction were established from detailed combustion simulations for the NPFs. The maximum error of temperature caused by the assumption of composition of air was reduced from 48.84% to under 1.6% for the NPFs using the systematic method. The method can overcome the difficulty that the concentrations of local species must be known when measuring the temperature by HI for NPFs.
Applied Optics, 1994
A detailed study for measuring the temperature distribution in axisymmetric flames by using a Talbot interferometer with circular gratings is presented. We increased the sensitivity of the interferometer by optimizing the pitch of the grating and the Talbot plane. We compare the experimental results with the values that were measured with a thermocouple to an accuracy of ±0.2% of full scale ±4 digits. Good agreement is seen between the temperatures measured by use of a thermocouple and those measured by use of Talbot interferometry.