: A cylinder with a diameter of 0.1 m and a length of 1 m is exposed to a fluid flowing at a velocity of 10 m/s. The fluid has a temperature of 50°C and a kinematic viscosity of 2 × 10^(-5) m^2/s. Calculate the heat transfer coefficient and the Nusselt number.
: A flat plate is maintained at a temperature of 80°C and is exposed to a fluid flowing at a velocity of 5 m/s. The fluid has a temperature of 20°C and a kinematic viscosity of 1.5 × 10^(-5) m^2/s. Calculate the heat transfer coefficient and the Nusselt number.
Since the Reynolds number is less than 5 × 10^5, the flow is laminar. Using the correlation for laminar flow over a flat plate, we can calculate the Nusselt number: : A cylinder with a diameter of 0
Nu = 0.664 × Re^0.5 × Pr^0.33 = 0.664 × (333,333)^0.5 × 2.58^0.33 = 250.3
h = Nu × k/L = 250.3 × 0.025 W/m·K / 1 m = 6.26 W/m^2·K : A flat plate is maintained at a
External forced convection occurs when a fluid flows over a surface, driven by an external agent such as a fan or a pump. This type of convection is commonly encountered in various engineering applications, including heat exchangers, electronic cooling systems, and wind turbines. In Chapter 7 of Cengel's book, the author provides an in-depth analysis of external forced convection, covering topics such as the velocity and thermal boundary layers, laminar and turbulent flow, and the calculation of heat transfer coefficients.
Re = ρUL/μ = (1000 kg/m^3 × 5 m/s × 1 m) / (1.5 × 10^(-5) kg/m·s) = 333,333 Since the Reynolds number is less than 5
: Using the solution manual, we can find the solution to this problem. First, we calculate the Reynolds number: