Measurements of three-dimensional mean flame surface area ratio in turbulent premixed Bunsen flames

2009 ◽  
Vol 32 (2) ◽  
pp. 1771-1777 ◽  
Author(s):  
Yung-Cheng Chen
Keyword(s):  
Surface Area ◽  
Three Dimensional ◽  
Area Ratio ◽  
Flame Surface ◽  
Surface Area Ratio ◽  
Bunsen Flames ◽  
Turbulent Premixed

Palatal Surface Area of Maxillary Plaster Casts—A Comparison between Two-Dimensional and Three-Dimensional Measurements

2007 ◽  
Vol 44 (4) ◽  
pp. 381-390 ◽  
Author(s):  
Tron A. Darvann ◽  
Nuno V. Hermann ◽  
Bjarne K. Ersbøll ◽  
Sven Kreiborg ◽  
Samuel Berkowitz
Keyword(s):  
Surface Area ◽  
Three Dimensional ◽  
Area Ratio ◽  
Two Dimensional ◽  
Surface Area Ratio ◽  
Dimensional Measurement ◽  
Interobserver Error ◽  
Dimensional Measurements ◽  
The Relationship ◽  
Plaster Casts

Objective: To investigate the relationship between corresponding two-dimensional and three-dimensional measurements on maxillary plaster casts taken from photographs and three-dimensional surface scans, respectively. Materials and Methods: Corresponding two-dimensional and three-dimensional measurements of selected linear distances, curve lengths, and (surface) areas were carried out on maxillary plaster casts from individuals with unilateral or bilateral cleft lip and palate. The relationship between two-dimensional and three-dimensional measurements was investigated using linear regression. Results and Conclusions: Error sources in the measurement of three-dimensional palatal segment surface area from a two-dimensional photograph were identified as photographic distortion (2.7%), interobserver error (3.3%), variability in the orientation of the plaster cast (3.2%), and natural shape variation (4.6%). The total error of determining the cleft area/palate surface area ratio was 15%. In population studies, the effect of using two-dimensional measurements is a decrease of discriminating power. In well-calibrated setups, a two-dimensional measurement of the cleft area/palate surface area ratio may be converted to a three-dimensional measurement by use of a multiplication factor of 0.75.

Clinical implication of renal allograft volume to recipient body surface area ratio in pediatric renal transplant

2018 ◽  
Vol 22 (8) ◽  
pp. e13295
Author(s):  
Michael E. Chua ◽  
Jin Kyu Kim ◽  
Michele Gnech ◽  
Jessica M. Ming ◽  
Bisma Amir ◽  
...  
Keyword(s):  
Renal Transplant ◽  
Surface Area ◽  
Body Surface Area ◽  
Body Surface ◽  
Clinical Implication ◽  
Renal Allograft ◽  
Area Ratio ◽  
Surface Area Ratio ◽  
Pediatric Renal Transplant

scholarly journals Effects of Turbulent Reynolds Number on the Displacement Speed Statistics in the Thin Reaction Zones Regime of Turbulent Premixed Combustion

2011 ◽  
Vol 2011 ◽  
pp. 1-19 ◽  
Author(s):  
Nilanjan Chakraborty ◽  
Markus Klein ◽  
R. S. Cant
Keyword(s):  
Reynolds Number ◽  
Strain Rate ◽  
Surface Density ◽  
Three Dimensional ◽  
Flame Surface ◽  
Tangential Strain ◽  
Turbulent Reynolds Number ◽  
Qualitative Nature ◽  
Displacement Speed ◽  
Turbulent Premixed

The effects of turbulent Reynolds number on the statistical behaviour of the displacement speed have been studied using three-dimensional Direct Numerical Simulation of statistically planar turbulent premixed flames. The probability of finding negative values of the displacement speed is found to increase with increasing turbulent Reynolds number when the Damköhler number is held constant. It has been shown that the statistical behaviour of the Surface Density Function, and its strain rate and curvature dependence, plays a key role in determining the response of the different components of displacement speed. Increasing the turbulent Reynolds number is shown to reduce the strength of the correlations between tangential strain rate and dilatation rate with curvature, although the qualitative nature of the correlations remains unaffected. The dependence of displacement speed on strain rate and curvature is found to weaken with increasing turbulent Reynolds number when either Damköhler or Karlovitz number is held constant, but the qualitative nature of the correlation remains unaltered. The implications of turbulent Reynolds number effects in the context of Flame Surface Density (FSD) modelling have also been addressed, with emphasis on the influence of displacement speed on the curvature and propagation terms in the FSD balance equation.

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