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1. Migration and fuel use in rural Zambia

   https://doi.org/10.1007/s11111-021-00385-7  

   Wu, Yu; Entwisle, Barbara; Sinai, Cyrus; Handa, Sudhanshu (December 2021, Population and Environment)

   Abstract What is the effect of migration on fuel use in rural Zambia? Opportunities to increase income can be scarce in this setting; in response, households may pursue a migration strategy to increase resources as well as to mitigate risk. Migrant remittances may make it possible for households to shift from primary reliance on firewood to charcoal, and the loss of productive labor through migration may reinforce this shift. This paper uses four waves of panel data collected as part of the Child Grant Programme in rural Zambia to examine the connection between migration and the choice of firewood or charcoal as cooking fuel and finds evidence for both mechanisms. Importantly, this paper considers migration as a process, including out as well as return migration, embedding it in the context of household dynamics generally. Empirical results suggest that while out-migration helps move households away from firewood as a fuel source, return migration moves them back, but because the former is more common, the overall effect of migration is to shift households away from primary reliance on firewood. 

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2. Transcritical and Supercritical Fuel Sprays in Subcritical Environments

   Kempin, Robert; Vinod, Kaushik N; Morris, Owen; Fang, Tiegang (June 2024, Proceedings of ICLASS 2024 the 16th Triennial International Conference on Liquid Atomization and Spray Systems)

   As fuel injection systems advance towards higher injection pressures and the combustor environment increases in both temperature and pressure in the pursuit of improved emissions and efficiency, advanced combustion strategies are required. Injecting fuel as a supercritical fluid has the potential to improve fuel/air mixing and eliminate steps in the spray vaporization process. Experiments are carried out on a heated fuel injector in an open-air test cell using Mie scattering, Schlieren imaging, and long-distance microscopy to investigate changes in spray characteristics with varying temperature and pressure. Spray angle, spray penetration length, and vapor-liquid ratio data are collected and evaluated. Near-nozzle imaging shows distinct changes in spray morphology during the initial microseconds of spray formation. Sprays injected under conditions further into the supercritical regime exhibit increased spray angle and vapor-to-liquid ratio. Spray penetration is found to decrease with increasing temperature. A jump in vapor-to-liquid ratio is observed in the vicinity of 568 K, indicating a transition in spray behaviour trending towards more rapid fuel/air mixing across the transcritical region. Changes in the micro-scale structure of the spray during the initial microseconds of spray formation exhibit this same narrow transition region. A significantly greater fraction of the spray plume is observed to be in a vapor or vapor-like state at a given time after injection initiation as the injection conditions are advanced into the supercritical state. These findings indicate that injection fuel as a supercritical fluid has the potential to improve the mixing of a fuel/air charge, and thus, improve combustion quality. 

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3. Noninvasive Fuel Flow Monitoring System for Vented Fuel Oil Heaters

   https://doi.org/10.3390/s23125664  

   Bond, Baxter; Vilagi, Alana; Pride, Dominique J. (June 2023, Sensors)

   In this work, we present hardware and firmware design and preliminary testing results for a noninvasive device for measuring fuel oil consumption in fuel oil vented heaters. Fuel oil vented heaters are a popular space heating method in northern climates. Monitoring fuel consumption is useful to understanding residential daily and seasonal heating patterns and understanding the thermal characteristics of buildings. The device is a pump monitoring apparatus (PuMA) that employs a magnetoresistive sensor to monitor the activity of solenoid driven positive displacement pumps, which are commonly used in fuel oil vented heaters. PuMA accuracy for calculating fuel oil consumption was evaluated in a lab setting and found to vary up to 7% from the measured consumption value during testing. This variance will be explored more in field testing. 

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4. Polymeric coatings for applications in electrocatalytic and photoelectrosynthetic fuel production

   https://doi.org/10.1039/C8TA05805A  

   Wadsworth, B. L.; Khusnutdinova, D.; Moore, G. F. (November 2018, Journal of Materials Chemistry A)

   Applications of polymeric coatings have emerged as a promising direction for preparing multilayered assemblies and controlling surface properties. In addition to providing a foundation for interfacing soft materials onto solid supports, polymers afford opportunities to develop hybrid constructs with properties difficult to achieve using monolayer-based chemical modification methods. In particular, the microenvironments of polymers are proposed to facilitate charge transfer to redox-active sites, manage delivery of chemical substrates, improve product specificity during catalytic transformations, and lend chemical protection to underpinning solid-state supports as well as embedded components. In this article, we highlight selected examples of polymeric materials utilized in electrocatalytic and photoelectrosynthetic fuel production. 

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5. Effects of Needle Lift and Fuel Type on Cavitation Formation and Heat Transfer Inside Diesel Fuel Injector Nozzle

   Zeidi, Javad SM; Dulikravich, George S; Reddy, Sohail R; Darvish, Shadi (May 2017, International Symposium on Advances in Computational Heat Transfer, paper CHT-17-102, Naples, Italy, May 28-June 1, 2017)

   In the present study, the flow inside a real size Diesel fuel injector nozzle was modeled and analyzed under different boundary conditions using ANSYS-Fluent software. A validation was performed by comparing our numerical results with previous experimental data for a rectangular shape nozzle. Schnerr-Sauer cavitation model, which was selected for this study, was also validated. Two-equation k-ε turbulence model was selected since it had good agreement with experimental data. To reduce the computing time, due to symmetry of this nozzle, only one-sixth of this nozzle was modeled. Our present six-hole Diesel injector nozzle was modeled with different needle lifts including 30 μm, 100 μm and 250 μm. Effects of different needle lifts on mass flow rate, discharge coefficient and length of cavitation were evaluated comprehensively. Three different fuels including one Diesel fuel and two bio-Diesel fuels were also included in these numerical simulations. Behavior of these fuels was investigated for different needle lifts and pressure differences. For comparing the results, discharge coefficient, mass flow rate and length of cavitation region were compared under different boundary conditions and for several fuel types. The extreme temperature spike at the center of an imploding cavitation bubble was also analyzed as a function of time and initial bubble size. 

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