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Among elements of an intelligent transportation system for autonomous vehicles are embedded sensors for vehicle-to-structure and vehicle-to-road communications. Continuous operation of these sensors requires local electric power supply, especially in remote areas. Electric power sources are also needed for the structural health monitoring system, that is, for detecting any structural damage, whether natural (i.e. earthquake) or manmade (i.e. accident). Here we are providing results of part I of our unsteady numerical investigations for a generic vehicle (Ahmed body) passing under a freeway overpass at different distances from the side bridge columns. The study aimed at understanding the wind load on the bridge columns and wind energy potential generated from the passing vehicles at different distances from these columns under a typical freeway overpass that could be used for generating electric power.

Analytical calculations along with computational fluid dynamic (CFD) simulation of a Boeing 737-600 cabin with a single infector (a passenger) has been performed using a passive scalar gas with particle sizes similar to the sizes of influenza virus laden particles which are assumed to be comparable to the sizes of the Coronavirus laden particles. CFD results of the virus transport and concentration were used in conjunction with the Wells-Riley (WR) quanta estimation from two well-documented cases of influenza infection on airplanes (with the assumption that the infections were primarily from the airborne route), to estimate the infectious rate. The risk of infection is estimated by the quanta of viruses inhaled assuming 0.3 CFM of passive scalar gas corresponds to 1267 viruses/minute released. Results indicate that with a 3-hour flight, the risk of infection is nearly 50% for those sitting in the vicinity of the infector which is equal to 2-3 infections for 131 passengers.

Numerical and experimental investigations of shedding frequency of rotating smooth and wire-wrapped cylinders, placed in steady flow have been performed. The freestream mean velocity was 10 m/sec. and for the numerical investigations, the smooth cylinder diameter was 5 cm, which corresponds to an approximate Reynolds number based on cylinder’s diameter of 3.2x104. The wire-wrapped cylinder had a wire diameter of 5 mm and the ratios of pitch spacing to the cylinder diameter, p/D, was 1.0. The cylinder length to diameter ratio was 20. The rotation rates (λ) were 0.5 and 2.0. To obtain the shedding frequency, numerical probes were placed at 3D downstream, 0.5 D above the centerline, and at 0.5D, spaced along the spanwise direction and the shedding frequencies were obtained from spectra of the axial velocity. Results indicate that the lift for the wire-wrapped cylinder is nearly 150% of that of the smooth cylinder, however, it has a higher drag force.

The investigation has been divided into two parts. In part one, numerical investigations of the effect of humid air with different levels of humidity on gaseous emissions of a non-premixed combustion have been investigated. This part of the investigation was a feasibility study, focused on how different levels of humidity in the intake air affects the exhaust NO emission. Part two of the investigation was verification of the numerical results with a naturally aspirated engine with natural gas as the fuel. Here, we also investigated the impact of humid air intake on engine’s particulate matter (PM) emission. For the numerical investigations, the non-premixed combustion in a single cylinder was simulated using the presumed probability density function combustion model. Simulations were performed for dry as well as humid intake air for 0%, 15%, and 30% relative humidity (RH).

The effects of humid air on the performance of a naturally aspired three-cylinder diesel engine with low sulfur diesel fuel have been investigated. The additions of the humidity to intake air were performed with a variable steam generator using distilled water, where the relative humidity levels of the intake air were changed from the ambient conditions of 65% to 75% and 95% levels. The tests were performed at two approximate engine output brake horse powers (BHP) of 5.9, and 8.9. Results showed approximately 3.7% and 22.5% reduction in NOx emissions when the relative humidity of the air was increased from 65% (the ambient relative humidity) to 75% and 95% respectively. The addition of the humidity results in increases in the CO, CO₂, and particulate matter (PM), by approximately 3.7, 3.55, 14.9 percents at 5.9 BHP and 22, 2.8, and 9.3 percents at 8.9 BHP. There was no change in the brake specific fuel consumption (BSFC) at 5.9 BHP and about 2.7 increase in the BSFC at 8.9 BHP.