Trihalomethanes (THMs) are one of the most common classes of disinfection by-products. In this study. the temporo-spatial trends and health risks due to exposure to THMs in the Tabriz water distribution network were investigated. THMs series were analysed using gas chromatography equipped with electron capture detector. The non-carcinogenic and carcinogenic risks due to exposure to THMs were calculated using Monte Carlo simulations.Mean concentrations of THMs in January (winter) and June (summer) were 10.2 ± 9.3 µg/l and 252 ± 185.9 µg/l, respectively. More than 80% of THMs identified were bromodichloromethan.The mean values of lifetime cancer risks (LTCR) from THMs were calculated as 4.23E-06 and 2.38E-04 for winter and summer, respectively. This study showed that there were noticeable levels of THMs in Tabriz's distribution network water, especially in the centre of the city. Although non-carcinogenic risks from THMs were below permissible recommended levels, carcinogenic risks likely remain due to high levels of THMs in some locations.

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The automotive industry is under obligation to meet regulations for emission control that has resulted in further use of turbochargers in passenger cars to enable downsizing and increase engine power density. In this study, a set of numerical simulations are conducted along two turbocharger compressor speed lines of 150,000 rpm and 80,000 rpm to analyse and validate the results against experimental data. The domain includes the full compressor stage comprising intake, impeller as a Multiple Reference Frame, diffuser and outlet. The k-omega SST turbulence model with three different mesh sizes is used tosolve the compressible flow using ANSYS Fluent software. Three points on each speed-line are selected:one point each in regions close to surge and choke and a point in the stable zone of the compressor map. The simulations predict compressor performance in terms of the total–to–total pressure ratioand total–to–total efficiency. Results reveal the predicted pressure ratio error is in the range of 1-6%. At 150,000 rpm the pressure ratio is underpredicted for the point close to the surgebut overpredicted for the point close to the choke. However, the pressure ratio results are within 1% difference for 80,000 rpm. In all cases, the predicted efficiency increased when a finer mesh is used.While results are close to the experimental data in both the surge and stable areas of the map, the efficiency wasoverpredicted up to 20% in the region close to the choke. In conclusion, the finer mesh leads to higher pressure ratio and efficiency values that overpredict the performance, especially for the pointclose to choke.