Numerical Investigation on the Fluid Flow Characteristics of a Laminar Slot Jet on Solid Block Mounted on a Horizontal Surface

Abstract

Numerical simulation is carried out to investigate the flow characteristics of two-dimensional laminar incompressible slot jet flows. Simulations are done for a vertical slot jet on a block at the bottom wall, and the top wall is confined by the parallel surface. The reattachment length, detachment length, vortex center and the coefficient of friction (C f ) are analyzed for different types of flow patterns. The correlation between the Reynolds number (Re) with vortex center and reattachment length is recommended. A detailed study is reported on the horizontal velocity profiles at various downstream locations by varying the aspect ratio (AR) (2 ≤ AR ≤ 5), block width (0.25 ≤ w/D h ≤ 1.75), block height (0.25 ≤ h/D h ≤ 1.0) and the jet exit Reynolds numbers (100 ≤ Re ≤ 300). The critical Reynolds number for the formation of the secondary vortex is obtained. The numerical results indicated that the C f value increases while decreasing the distance between the jet and the impingement block. It is found that the effects of AR and Re are more influencing on the fluid flow field, compared to the block width and the block height.Keywords Coefficient of friction · Laminar flow · Reattachment length · Reynolds number · Single slot jet · Vortex center List of symbolsAV Adjacent vortex AR Aspect ratio of the domain = (L y /W ) C f Skin friction coefficient L x Length of the computational domain in the X direction (m) L y Length of the computational domain in the Y direction (m) D h Hydraulic diameter of the jet (m) h Height of the block (m) h/D h Dimensionless block height w Width of the block (m) w/D h Dimensionless block width W Width of the jet (m) 123 8078 Arab J Sci Eng (2014) 39:8077-8098

Flow Field and Heat Transfer Investigation of a Confined Laminar Slot Air Jet on a Solid Block

“…The subtle variation of Cf is observed with increasing Re and decreasing AR. From the graph, it is interesting to note, that the peak value of the coefficient of friction decreases with the increase of AR (Muthukannan et al (2014)) (Fig. 18).…”

“…The present authors (Muthukannan et al 2014) conducted a numerical study only on the fluid flow characteristics, of a laminar slot jet on a solid block mounted on a horizontal surface. In their previous research work they found the flow field characteristics for Re ranging from 50 to 300, block height, ranging from 0.25 to 1.0, and block width, ranging from 0.25 to 1.75 as the baseline case of AR5.The previous work has been confined by changing the AR ranging from 2 to 5 as the baseline case of Re 150.…”

Flow And Heat Transfer Characteristics Of Inclined Jet Impingement On A Flat Plate

“…Yan and Saniei [13] considered the heat transfer for an obliquely impinging circular air jet to a flat plate using a preheated wall transient liquid crystal technique. Muthukannan et al [18] investigated numerically the flow characteristics of two-dimensional laminar incompressible slot jet flow for a vertical slot jet on a block at the bottom wall. They investigated the reattachment length, detachment length, vortex center and the coefficient of friction for different types of flow *Sorumlu Yazar (Corresponding Author) e-posta : tamercalisir@gazi.edu.tr patterns.…”

Flow Analysis of Laminar Wall Jet over Curved Cavity with a Channel Mounted Fin

“…A strong effect of Reynolds number on size and locations of center of large vortices has been noticed near the lid for the deep cavity flow. [17]carried out Numerical simulations on two-dimensional incompressible slot jet flows. The reattachment length, center of vortex and coefficient of friction (C f ) are analyzed.…”