Abstract: An experimental study performed to investigate the effect of nanofluid forced convection heat transfer and fluid flow characteristic. Three types of nanofluids {γAl2O3, CuO and ZrO2-DIW} flow under laminar or turbulent condition in inner pipe. The shear thinning behavior of blood is more accurately modeled by non-Newtonian Blood Mimic Fluids BMF. Here heat transfer and friction factor correlations developed for nonreactive Newtonian and non-Newtonian BMF fluids of (water: glycerol: xanthan gums) and heparinized bovine blood. The results show that the BMF Nussult number (Nub) increased as increasing Graetz number, and as flow index (n) decreasing. Bovine blood gives the temperatures distribution similar to (BMF6) but with lower Nusselt number by (31.2%). The BMF friction factor increases with decreasing (n), but the Bovine blood gives higher friction factor as compared with BMF6 by (25.6%). It was observed that all nanofluids types showed higher heat transfer characteristics than the base fluid DIW. It was also noted that in the γAl2O3 shows higher enhancement than the other by (82.4%) at (Renf =12670) and (ɸ=1 vol.% ). Comparisons present experimental results with previously reported results it gives good agreement.Abstract: An experimental study performed to investigate the effect of nanofluid forced convection heat transfer and fluid flow characteristic. Three types of nanofluids {γAl2O3, CuO and ZrO2-DIW} flow under laminar or turbulent condition in inner pipe. The shear thinning behavior of blood is more accurately modeled by non-Newtonian Blood Mimic Fluids BMF. H...Show More
Abstract: Projects delivering on time and budget is still complex. This study presents actual project performance comparisons of the Design-Bid-Build “DBB” and Design-Build “DB” systems into Libyan projects. By analyzing 124 projects delivered by two methods and two types of companies (local and foreign) to provide objective comparison of cost and schedule performance. The results show that average DB cost was about 1.45 times larger than DBB. The project achieved by local and foreign companies, average cost overrun for DBB was 34%, and 26% respectively, Whilst only 10% and 0% for DB for local and foreign companies. The average time extension by local and foreign companies for DBB was 39.8%, and 43%, whilst only 32% and 0% for DB for local and foreign companies. DB projects executed by foreign company had little change order than DBB. This paper compares two project delivery systems, namely Design-Bid-Build and Design-Build, as well as two types of construction companies, local and foreign. Data for 124 projects were collected from Libyan Audit Bureau. In terms of the construction time and cost, the paper concludes that the foreign companies did a better job than the local companies. Also, provides quantitative data to support the delivery system selection with understanding its performance criteria.Abstract: Projects delivering on time and budget is still complex. This study presents actual project performance comparisons of the Design-Bid-Build “DBB” and Design-Build “DB” systems into Libyan projects. By analyzing 124 projects delivered by two methods and two types of companies (local and foreign) to provide objective comparison of cost and schedule p...Show More
