Primary Breakup of Turbulent Round Liquid Jets in Uniform Crossflows

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77302/1/AIAA-19397-547.pd

Laminar Soot Processes (LSP) Experiment: Findings From Space Flight Measurements

The present experimental study of soot processes in hydrocarbon-fueled laminar nonbuoyant and nonpremixed (diffusion) flames at microgravity within a spacecraft was motivated by the relevance of soot to the performance of power and propulsion systems, to the hazards of unwanted fires, and to the emission of combustion-generated pollutants. Soot processes in turbulent flames are of greatest practical interest, however, direct study of turbulent flames is not tractable because the unsteadiness and distortion of turbulent flames limit available residence times and spatial resolution within regions where soot processes are important. Thus, laminar diffusion flames are generally used to provide more tractable model flame systems to study processes relevant to turbulent diffusion flames, justified by the known similarities of gas-phase processes in laminar and turbulent diffusion flames, based on the widely-accepted laminar flamelet concept of turbulent flames. Unfortunately, laminar diffusion flames at normal gravity are affected by buoyancy due to their relatively small flow velocities and, as discussed next, they do not have the same utility for simulating the soot processes as they do for simulating the gas phase processes of turbulent flames

Could targeted food taxes improve health?

OBJECTIVE: To examine the effects on nutrition, health and expenditure of extending value added tax (VAT) to a wider range of foods in the UK. METHOD: A model based on consumption data and elasticity values was constructed to predict the effects of extending VAT to certain categories of food. The resulting changes in demand, expenditure, nutrition and health were estimated. Three different tax regimens were examined: (1) taxing the principal sources of dietary saturated fat; (2) taxing foods defined as unhealthy by the SSCg3d nutrient scoring system; and (3) taxing foods in order to obtain the best health outcome. DATA: Consumption patterns and elasticity data were taken from the National Food Survey of Great Britain. The health effects of changing salt and fat intake were from previous meta-analyses. RESULTS: (1) Taxing only the principal sources of dietary saturated fat is unlikely to reduce the incidence of cardiovascular disease because the reduction in saturated fat is offset by a rise in salt consumption. (2) Taxing unhealthy foods, defined by SSCg3d score, might avert around 2,300 deaths per annum, primarily by reducing salt intake. (3) Taxing a wider range of foods could avert up to 3,200 cardiovascular deaths in the UK per annum (a 1.7% reduction). CONCLUSIONS: Taxing foodstuffs can have unpredictable health effects if cross-elasticities of demand are ignored. A carefully targeted fat tax could produce modest but meaningful changes in food consumption and a reduction in cardiovascular disease