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Consider air flowing over a 1-m-long flat plate at a velocity of 3 m/s. Determine the convection heat transfer coeffecient and the Nusselt numbers at x=0.5 m and 0.75 m. Evaluate the air properties at 40 C and 1 atm.

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Final answer:

To determine the convection heat transfer coefficient and Nusselt numbers, you need to use equations involving the Nusselt number, Reynolds number, and Prandtl number. The air properties at 40°C and 1 atm are needed to calculate these values.

Step-by-step explanation:

The convection heat transfer coefficient can be determined using the following equation:

h = Nu * k / D

Where:

  • h is the convection heat transfer coefficient
  • Nu is the Nusselt number
  • k is the thermal conductivity of air
  • D is the characteristic length (in this case, the length of the flat plate).

The Nusselt number can be calculated using the equation:

Nu = 0.332 * Re^(1/2) * Pr^(1/3)

Where:

  • Re is the Reynolds number, which is given by Re = V * L / v
  • Pr is the Prandtl number, which can be assumed to be around 0.7 for air
  • V is the velocity of air
  • L is the characteristic length (in this case, the length of the flat plate)
  • v is the kinematic viscosity of air, which can be calculated using the equation v = μ / ρ, where μ is the dynamic viscosity of air and ρ is the density of air.

Given that air properties are evaluated at 40°C and 1 atm, you can use the relevant values for air properties at those conditions to calculate the convection heat transfer coefficient and the Nusselt numbers at x = 0.5 m and x = 0.75 m. Please provide the specific values for air properties at 40°C and 1 atm.

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