Net Heat Exchange Given Area 2 And Shape Factor 21 Calculator

Formula Used:

\[ Q_{1-2} = A_2 \times F_{21} \times (E_{b1} - E_{b2}) \]

Surface Area of Body 2 (A₂):

m²

Radiation Shape Factor 21 (F₂₁):

Emissive Power of 1st Blackbody (E₆₁):

W/m²

Emissive Power of 2nd Blackbody (E₆₂):

W/m²

Net Heat Transfer (Q₁-₂):

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1. What is Net Heat Exchange?

Net Heat Exchange refers to the amount of heat that is transferred per unit of time between two surfaces through radiation. It is a fundamental concept in thermodynamics and heat transfer engineering.

2. How Does the Calculator Work?

The calculator uses the radiation heat transfer formula:

\[ Q_{1-2} = A_2 \times F_{21} \times (E_{b1} - E_{b2}) \]

Where:

\( Q_{1-2} \) — Net heat transfer from surface 1 to surface 2 (W)
\( A_2 \) — Surface area of body 2 (m²)
\( F_{21} \) — Radiation shape factor from surface 2 to surface 1
\( E_{b1} \) — Emissive power of 1st blackbody (W/m²)
\( E_{b2} \) — Emissive power of 2nd blackbody (W/m²)

Explanation: The formula calculates the net radiative heat transfer between two blackbody surfaces based on their areas, shape factor, and emissive powers.

3. Importance of Heat Transfer Calculation

Details: Accurate heat transfer calculation is crucial for thermal system design, energy efficiency analysis, HVAC system design, and various industrial applications involving heat exchange.

4. Using the Calculator

Tips: Enter surface area in m², shape factor (0-1), and emissive powers in W/m². All values must be valid positive numbers with shape factor between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is radiation shape factor?
A: Radiation shape factor (view factor) is the fraction of radiation energy leaving one surface that strikes another surface directly.

Q2: What are typical values for shape factor?
A: Shape factor values range from 0 to 1, where 0 means no radiation exchange and 1 means complete enclosure.

Q3: What is emissive power of a blackbody?
A: Emissive power is the energy of thermal radiation emitted per unit time from each unit area of a blackbody surface at a given temperature.

Q4: Are there limitations to this formula?
A: This formula assumes blackbody radiation and doesn't account for reflectivity, transmissivity, or gray body characteristics.

Q5: When is this formula applicable?
A: This formula is applicable for radiative heat transfer between two blackbody surfaces in a non-absorbing medium.