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A transient analysis has been carried out in detail using the finite difference method for the roll heat pipe wish is firstly studied by Jalilvand [1] in photocopy machines. The objective of this study is to better understand this type of heat pipes for further heat recovery applications or other designs processes that are essentially transient. The numerical results shows that the roll heat pipe perform better than the annular heat pipe of same dimension and the condenser region is essentially controlled by the heat Input and the convective heat transfer coefficient.
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