Biodiverse is a tool for the spatial analysis of diversity using indices based on taxonomic, phylogenetic and matrix (e.g. genetic dissimilarity) relationships. The explosion in georeferenced biological specimen and survey data means there is an increasing need for such tools. Biodiverse supports four processes: 1) linked visualisation of data distributions in geographic, taxonomic, phylogenetic and matrix spaces; 2) spatial moving window analyses including richness, endemism, phylogenetic diversity and beta diversity; 3) spatially constrained agglomerative cluster analyses; and 4) randomisations for hypothesis testing. Biodiverse is open-source and supports user developed extensions. It can be used both through a graphical user interface and scripts. Biodiverse can be downloaded from .

The optical emissions from a turbulent, nonpremixed, liquid fueled (n-heptane) combustor were investigated using two optical imaging systems: a high spectral resolution (~0.3 nm), single wavelength system; and a low resolution (~5 nm), multi-wavelength system intended to mimic the response of a practical sensor. The goal was to develop signal interpretation strategies that would allow an optical sensor system to monitor needed properties in liquid-fueled combustors and engines. The research focused on the chemiluminescent emissions from OH*, CH*, and C 2 *. Data were acquired for a range of fuel and air flow rates (equivalence ratios 0.6-1.3), and for radial slices through the nominally axisymmetric combustor over the complete combustor length. Without correction, both OH* and CH* emission were found to be good indicators of heat release rate only over a narrow band of lean equivalence ratios. In addition, OH* provides information on the postcombustion zone conditions. A nearly linear relationship was found between the overall equivalence ratio of the combustor and the ratio of the emission integrated over the combustor volume from two radical species, with the ratio C 2 */OH* exhibiting the greatest sensitivity. The correlation was also applied to estimate the radially averaged equivalence ratio of the reaction zone along the length of the combustor. With the multiwavelength sensor set to simultaneously monitor the broadband background from the flame, its background corrected output agreed well with the high spectral resolution results, suggesting that a properly designed optical sensor system would be capable of determining local combustor conditions such as reaction zone equivalence ratio and heat release rate.

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This paper describes an experimental investigation of the spray created by Jet A fuel injection from a plate containing sharp edged orifice 0.018in.(457μm) in diameter and L∕D ratio of 10 into the crossflow of preheated air (555K) at elevated pressure in the test section (4atm) and liquid to air momentum flux ratio of 40. A two component phase Doppler particle analyzer was used for measuring the characteristics of the spray. The Weber number of the spray in crossflow was varied between 33 and 2020 and the effect of Weber number on spray properties was investigated. It was seen that the shear breakup mechanism dominates at Weber number greater than about 300. Droplets’ diameters were found to be in the range of 15–30μm for higher values of Weber numbers, while larger droplets (100–200μm) were observed at Weber number of 33. Larger droplets were observed at the periphery of the spray. The droplet velocities and diameters were measured in a plane 30mm downstream of the orifice along the centerline of the spray at an incoming airflow Mach number of 0.2. The droplets reach a maximum of 90% of the flow velocity at this location. The velocity of the droplets in the directions perpendicular to the airflow direction is higher at the periphery of the spray possibly due to the presence of larger droplets there. The rms values of the droplet velocities are highest slightly off the centerline of the spray due to the presence of vortices and shear layers around the liquid jet. The data presented here improve the understanding of spray formation processes, and provide benchmark data for computational fluid dynamics (CFD) code validation.

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