# Tag Info

## New answers tagged heat-transfer

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This is an outline for a solution that should get you going: Step one - find an equation describing the convection of the yellow medium. $\dot{m}_{yellow}$ is determined by $T_{in}$, $T_{out}$ (340°C) and the shape and physical properties of the heat exchanger, how they are situated to each other, etc. To define this function \$\dot{m}_{yellow}(T_{in},T_{out})...

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A heat pump or refrigeration device is simply a machine designed to move heat from cold to hot (heat moves by itself only from hot to cold). All refrigeration equipment I am aware of uses the latent heat of fusion/vaporization to do this, as the temperature of vaporization/condensation changes with pressure. The range of temperature available will be set ...

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I was able to find this online: https://sbainvent.com/heat-transfer/convection/convective-heat-transfer-coefficient-flat-plate/ This does not put a lower limit on Re for the laminar flow correlation. There has been a lot of research in this area! Nusselt number correlations for varying geometries and geometry patterns are available in droves online. Academic ...

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$$\text{Absolute maximum efficiency} = \text{Carnot Efficiency} = \frac{T_{hot}-T_{cold}}{T_{hot}}$$ where all temperatures are expressed in degrees Kelvin (= degrees C + 273). A very well built and designed engine with high temperature differentials, high pressure and using Hydrogen (not at all recommended) or Helium working gas might achieve 10% - 50%+ of ...

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Even in gas household water heaters if you don't use a pressure relief valve the temperature will go above 100 °C rapidly if you bypass the thermostat. But it will explode! If you have a water tank designed to take the required pressure you don't need any other refrigerant, just heat it up like a pressure cooker. Many cars' radiators circulate water above ...

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This is not an answer but I couldn't fit it all in a comment. First of all it will depend very much on the heat pump design. To my understanding, heat pumps are designed with a specific refrigerant in mind and with a specific range of operating temperatures. Changing the refrigerant you'd need to modify a lot of parameters (flow, exchange areas etc). ...

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