## THERMAL SCIENCE

International Scientific Journal

### ANALYSIS OF HEAT AND MASS TRANSFER OF THE DIFFERENT MOIST OBJECT GEOMETRIES WITH AIR SLOT JET IMPINGING FOR FORCED CONVECTION DRYING

**ABSTRACT**

In the present work, the effect of the different geometric moist objects with straight and reverse semi-circular on the heat and mass transfer enhancement of the jet drying was conducted with a numerical analysis. The drying jet was a laminar 2-D jet stationed at a constant jet distance from the moist object. The diameter of the object, jet distance from the moist object and initial jet height were fixed in all cases. Temperature and mass distributions were obtained inside the object for different jet velocities. A finite volume method was used to solve the governing equations for momentum and energy by using ANSYS Fluent 17.0 software program. Calculations were performed for four different Reynolds numbers, namely, Re = 100, 200, 300, and 400. It was found good agreement with the experimental data available in the literature. The results showed that the geometry of straight semi-circular moist object had better performance of heat and mass transfer than that of the reverse moist object geometry. In addition, increasing Reynolds number showed a positive effect on heat and mass transfer. Locally, jet drying was found to be most effective near the stagnation point on the leading side of the objects.

**KEYWORDS**

PAPER SUBMITTED: 2016-07-21

PAPER REVISED: 2017-06-01

PAPER ACCEPTED: 2017-06-21

PUBLISHED ONLINE: 2017-07-08

**THERMAL SCIENCE** YEAR

**2018**, VOLUME

**22**, ISSUE

**6**, PAGES [2943 - 2953]

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