## THERMAL SCIENCE

International Scientific Journal

### NUMERICAL ANALYSIS OF MIXED CONVECTION IN PULSATING FLOW FOR A HORIZONTAL CHANNEL WITH A CAVITY HEATED FROM BELOW

**ABSTRACT**

In this study, a channel with a cavity heated from below is numerically investigated for the mixed convection case in pulsating flow for a range of Richardson numbers (Ri=0.1, 1, 10, 100) at Reynolds number of 50 in the laminar flow regime. At the inlet of the channel, pulsating velocity is imposed for Strouhal numbers between 0.1 to 1 and velocity amplitude ratio between 0.3 to 0.9. The effect of the pulsation frequency, amplitude and Richardson number on the heat transfer enhancement is numerically analyzed. The results are presented in terms of streamlines, isotherm plots and averaged Nusselt number plots. FFT plots for the Nusselt number response to single sinusoidal velocity forcing at the inlet and nonlinearity in the response is also provided.

**KEYWORDS**

PAPER SUBMITTED: 2012-04-13

PAPER REVISED: 2013-09-04

PAPER ACCEPTED: 2013-10-07

PUBLISHED ONLINE: 2013-11-16

**THERMAL SCIENCE** YEAR

**2016**, VOLUME

**20**, ISSUE

**Issue 1**, PAGES [35 - 44]

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