α angle of attack, rad Γ circulation, m2s−1 λ wake wavelength, m ρ∞ free-stream air density, kgm −3 τ panel tangential vector ω angular velocity, rad s−1 a non-dimensional distance between aerofoil mid-chord and centre of rotation A panel area, m b semi-chord, m ∆b panel span, m B wingspan, m c aerofoil chord, m ∆c panel chord, m C Theodorsen’s function, C(k) = F (k) + iG(k) Cd sectional drag c...

In this research, the heat transfer coefficient (HTC) and pressure drop of alternating cross-section flattened (ACF) tubes were investigated experimentally compared with same parameters a circular tube. Three different ACF fabricated from copper tubing an internal diameter 4.5 mm, thickness 1 length 400 mm. The twist angles 30, 45, 90°. experimental ranges covered mass flux 729–1,434 kg/m2s 12–...

in this research, heat transfer enhancement and simultaneous effect of that on pressure drop inside condensers with twisted tape inserts are investigated. a refrigeration system is designed for attaining to maximum level of heat transfer with minimum pressure drop. the test condenser is a double pipe heat transformer with inner and outer diameter of 10.7mm and 12.7mm for internal pipe, respecti...

the pressure drop of refrigerant r-134a flow boiling inside a horizontal tube has been investigated experimentally. the test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. these instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. this system consisted of three electrically heated evapor...

The pressure drop of refrigerant R-134a flow boiling inside a horizontal tube has been investigated experimentally. The test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. These instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. This system consisted of three electrically heated evapor...