CFD Analysis for Heat Transfer Enhancement inside a Circular Tube with Half-Length Upstream and Half-Length Downstream Twisted Tape

<table>Experimental and CFD wall temp and surface temp for upstream location for <svg height="15.2875" id="M65" style="vertical-align:-3.50804pt" version="1.1" viewbox="0 0 60.525002 15.2875" width="60.525002" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> W/<svg height="15.8375" id="M66" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 20.375 15.8375" width="20.375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,15.775)"><path d="M797 0h-214v26q46 5 58 17.5t12 63.5v167q0 116 -88 116q-48 0 -112 -52q3 -18 3 -42v-195q0 -46 11 -58t53 -17v-26h-214v26q48 5 59.5 17t11.5 60v172q0 115 -88 115q-47 0 -109 -52v-235q0 -47 10 -59.5t48 -17.5v-26h-211v26q50 5 62.5 17t12.5 60v207q0 48 -9 59.5
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</svg>, Re = 25000, and <svg height="12.4375" id="M67" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 57.287498 12.4375" width="57.287498" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>.</table>

Journal of Thermodynamics

fig13

Figure 13

Figure 13: CFD Analysis for Heat Transfer Enhancement inside a Circular Tube with Half-Length Upstream and Half-Length Downstream Twisted Tape 