36 lines
1.2 KiB
Markdown
36 lines
1.2 KiB
Markdown
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---
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author: Akbar Rahman
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date: \today
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title: MMME2047 // Heat Transfer
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tags: [ heat_transfer ]
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uuid: d3ba66c2-e486-464a-a4df-f23f2155ee6d
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lecture_slides: [ ./lecture_slides/6ConvHeatTransfer-without-written-comments.pptx ]
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lecture_notes: [ ./lecture_notes/ConvectHeatTrans2022-2023.pdf ]
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exercise_sheets: [ ./exercise_sheets/ExamplesConvectionHeatTransfer.pdf ]
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---
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# Convection
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- conduction and radiation heat transfer can be estimated by calculations and properties
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- convection is dependent on fluid properties, flow type, and flow characteristics
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The rate of convective heat transfer, $\dot Q$, is given by
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\begin{equation}
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\dot Q = hA(T_f-T_w)
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\label{eqn:convectionheattransfer}
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\end{equation}
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where $T_w$ is the wall temperature, $T_f$ is the fluid temperature, $A$ is the area of heat flow,
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and $h$ is the heat transfer coefficient.
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## Thermal Resistance
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Equation \ref{eqn:convectionheattransfer} can also be expressed in terms of thermal resistance, $R_\text{thermal}$:
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$$\dot Q = \frac{T_f-T_w}{\sum R_\text{thermal}}$$
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where $R_\text{thermal} = \frac{1}{hA}$.
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In a way this analogous to Ohm's law, specifically with resistors in series ($I = \frac{\Deta V}{\sum R_\text{electrical}}$).
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