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Consider the following statements for Nucleate boiling: 1. For water, the critical heat flux does not exceed 1 MW/m2. 2. Nucleate boiling is the most desirable boiling regime in practice because of high heat transfer rates. 3. Heat flux increases at a higher rate with increase in temperature. Which of the above statements is/are correct?

Consider the following statements for Nucleate boiling: 1. For water, the critical heat flux does not exceed 1 MW/m2. 2. Nucleate boiling is the most desirable boiling regime in practice because of high heat transfer rates. 3. Heat flux increases at a higher rate with increase in temperature. Which of the above statements is/are correct? Correct Answer 2 only

Explanation:

Nucleate boiling:

  • Nucleate boiling is a type of boiling that takes place when the surface temperature is hotter than the saturated fluid temperature by a certain amount but where the heat flux is below the critical heat flux. (For water, critical heat flux > 1 MW/m2).
  • Nucleate boiling is the most desirable boiling regime because high heat transfer rates can be achieved with with relatively small value of difference between the surface temperature (T) and the Saturation temperature (Ts).
  • Heat transfer rate increase at a lower rate as ΔTe increases.
  • From heat transfer point of view, nuclear boiling regime is the most desirable range to operate.

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