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CorrelationsMazhar IqbalBSME-12213

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1.For Helically Coiled Tubes By Dravid AN, Smith KA, Merrill EW,

Brain

2.Vertical Plane (Natural Convection) By Churchill and Chu

3.Spiral Plate Heat Exchanger By R.Rajavel & K.Saravana

Correlations

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By Dravid AN, Smith KA, Merrill EW, Brain

Where Nu is the Nusselt number De is the Dean number Pr is the Prandtl number

1. Helically coiled tubes

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The Dean number (De) is a dimensionless number in fluid mechanics, which happens in the study of flow in curved pipes and channels.

Where “ρ “is the density of the fluid “μ“ is the dynamic viscosity “V” is the axial velocity scale “d” is the diameter (other shapes are represented by an equivalent

diameter) “R” is the radius of curvature of the path of the channel.

The Dean number is therefore the product of the Reynolds number (based on axial flow through a pipe of diameter ) and the square root of the curvature ratio.

1. Helically coiled tubes cont..

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Range: Prandtl number (5–175) Dean number (50–200) laminar flow heat transfer both in the fully developed region and in the

thermal entrance region

1. Helically coiled tubes cont..

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2. Natural Convection Adjacent To Vertical Planes

• By Churchill and Chu Correlation

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2. Natural Convection Adjacent To Vertical Planes cont..

• Range:

• For laminar flow (RaL< 10^9)

• Range:• For all flow regimes

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By R.Rajavel & K.Saravana

Range:* 3750 > Re< 8750* 4< Pr< 6

3. Spiral Plate Heat Exchanger

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Heat and mass transfer by R.K.Rajput An Experimental Study of Spiral Plate Heat

Exchanger for Electrolytes By R.Rajavel &K. Saravanan

References

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