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In this study, the flow of Cu/oil nanofluids over an impermeable semi-infinite plate was investigated. A complete single-phase modeling of nanofluids flowing over a semi-infinite plate was performed, bringing into account, real experimental data of oil-based nanofluids. The empirical correlations revealed that the viscosity and thermal conductivity of the pure oil and oil-based nanofluids strongly depend on temperature. The similarity transformation method was utilized to transform governing partial differential equations into coupled nonlinear ordinary differential equations solved by employing the standard Runge-Kutta. The results showed that even low volumetric fraction of copper/oil nanofluids noticeably enhanced the heat transfer; however, such behavior was not predicted accounting the classic modeling of nanofluids. Furthermore, both hydrodynamics and thermal characteristics were reliant on the thermal boundary conditions, which this seems to have received a marginal focus in the existing literature. K E Y W O R D S Cu/oil nanofluids, heat transfer characteristics, hydrodynamics, low volumetric nanofluid, nanofluids flow over a semi-infinite plate, Runge-Kutta, thermal conductivity, viscosity

Mechanical and pneumatic systems are used to transfer solids (grains, particles, and the likes.). Although mechanical systems have been used for many years, they cause partial breakage, noise, and dust of the transferred products. Pneumatic systems are operated in two different ways: blowing and vacuum, allowing the grains to be transported more efficiently and without damage. In this study, conveying systems using compressed-air-operated vacuum generators (air amplifier) were investigated. Air Amplifiers are some energy converters that work based on Coanda and Venturi effects as an aerodynamic device. The Venturi effect is based on Bernoulli's theorem in the fluid flow, where a vacuum region is created from the conversion of a high-pressure fluid (gas or liquid) to a high-velocity flows. The Coanda effect actualizes the formation of a thin boundary layer of motive fluid along with a chambered surface. In this report, using the SolidWorks program, the whole system in general, and the fragment of air amplifier, in particular, are designed. Fluid flow analysis using the CFD package of Ansys CFX 14, and the Flow Simulation part of SolidWorks was performed to optimize the novel air amplifier. Clearance of the ring nozzle and the chamber's angel as the critical part of the air amplifiers were considered in this optimization. Various nozzle clearance as (d = 0.3mm, 0.4 mm, and 0.5 mm), chamber's angle as (α = 20º, 25º, 30º), under various inlet pressures (P = 1, 2, 3, 4, 5, 6, 7, 8 bars) well-considered. As a result, after optimizing air amplifiers, the material transfer system's performance is rising up to 60%, noise and the amount of dust generated in the environment are reduced significantly, and the grain is transferred safely without damage.