Heat transfer and hydraulic resistance of a flat channel with discrete wall roughness in the form of inclined trench dimples
I.A. Davletshin1, N.S. Dushin1, O.A. Dushina1, N.I. Mikheev1, R.R. Shakirov1, S.A. Isaev2
a:2:{s:4:"TYPE";s:4:"HTML";s:4:"TEXT";s:193:"1Institute of Power Engineering and Advanced Technologies, FRC “Kazan Scientific Center RAS”, Kazan, Russia
2State Marine Technical University, Saint Petersburg, Russia";}
Keywords: dimples, heat-transfer intensification, hydraulic resistance
Abstract
An experimental study of heat transfer and hydraulic losses in a channel with one wall being a surface with trench dimple, was carried out. The working surface had four rows of dimples located alternately at angles of 45° and -45° to the channel axis. In the laminar regime, the transfer of heat and the losses of pressure turned out to be close to the parameters of a smooth channel. In the turbulent regime, a 1.5-fold intensification of heat transfer with respect to the transfer of heat in a smooth channel was obtained. The dependence of the increase in pressure losses on the Reynolds number qualitatively agreeing with the dependence for the channels with sandy roughness is obtained.
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