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D. Singh and S. Kango
Re D Reynolds number defined based on the heated cylinder, Re D =
ρU jet D
μ
.
S
Width of slot jet, m.
T jet Jet exit temperature, K.
T w Impingement wall temperature, K.
U jet Jet exit velocity, m/s.
Greek Symbol
θ
Angle.
μ
Density, kg/m
3 .
ρ
Dynamic viscosity, kg/m s.
1 Introduction
Turbulent jet impingement cooling is commonly used in real engineering applications, i.e., industrial cooling, heating and drying of a system. Extensively, studies have
been carried out by various researchers using cooling of flat surfaces by using this
technique [1–4]. However, the literature on jet impingement on cylinder is limited.
Gori and Bossi [5] experimentally investigated slot jet impingement heat transfers
on cylinder for different Reynolds numbers and h/S = 2–10. They also provided the
heat transfer correlations for the average Nu for h/S from the two to ten. Authors
observed that h/S = 6 provides maximum heat transfer rate. Similar study was also
carried out by the same authors for different parameters for Re D = 4000–22,000
[6]. It was observed that at h/S = 8 pprovided maximum Nu value for the range of
Reynolds number (4000–22000). Based on their earlier work, they also observe that
the maximum Nu value is obtained at D/S = 4. On the other hand, D/S = 2 provides
maximum heat transfer rate. McDaniel and Webb [7] studied the heat transfer characteristics cylinder by turbulent slot jet impinging. In their study, Re D , varied from
600–8000. They used both sharp edge and contour nozzles to order to understand
the effect of nozzle shape. In this study, cylinder diameter to jet width was varied
from 0.66 to 2. They also reported correlations for the average Nu for the range of
parameters considered.
Olsson et al. [8] numerically investigate the turbulent slot jet impingement heat
transfer on cylinder placed on a flat plate; considering food processing is a potential
application. As the flat surface confines the fluid flow, the flow and heat transfer
characteristics of this study differ from the geometries considered by [5–7]. In this
study, the Re S from 23,000 to 100,000, h/D varied from 2 to 8. In order to investigate
the curvature effect, they considered S/D in the range 0.29–1.14. Dirita et al. [9] also
carried out numerical investigation similar to the geometry considered by Olsson
et al. [8].
D. Singh and S. Kango
Re D Reynolds number defined based on the heated cylinder, Re D =
ρU jet D
μ
.
S
Width of slot jet, m.
T jet Jet exit temperature, K.
T w Impingement wall temperature, K.
U jet Jet exit velocity, m/s.
Greek Symbol
θ
Angle.
μ
Density, kg/m
3 .
ρ
Dynamic viscosity, kg/m s.
1 Introduction
Turbulent jet impingement cooling is commonly used in real engineering applications, i.e., industrial cooling, heating and drying of a system. Extensively, studies have
been carried out by various researchers using cooling of flat surfaces by using this
technique [1–4]. However, the literature on jet impingement on cylinder is limited.
Gori and Bossi [5] experimentally investigated slot jet impingement heat transfers
on cylinder for different Reynolds numbers and h/S = 2–10. They also provided the
heat transfer correlations for the average Nu for h/S from the two to ten. Authors
observed that h/S = 6 provides maximum heat transfer rate. Similar study was also
carried out by the same authors for different parameters for Re D = 4000–22,000
[6]. It was observed that at h/S = 8 pprovided maximum Nu value for the range of
Reynolds number (4000–22000). Based on their earlier work, they also observe that
the maximum Nu value is obtained at D/S = 4. On the other hand, D/S = 2 provides
maximum heat transfer rate. McDaniel and Webb [7] studied the heat transfer characteristics cylinder by turbulent slot jet impinging. In their study, Re D , varied from
600–8000. They used both sharp edge and contour nozzles to order to understand
the effect of nozzle shape. In this study, cylinder diameter to jet width was varied
from 0.66 to 2. They also reported correlations for the average Nu for the range of
parameters considered.
Olsson et al. [8] numerically investigate the turbulent slot jet impingement heat
transfer on cylinder placed on a flat plate; considering food processing is a potential
application. As the flat surface confines the fluid flow, the flow and heat transfer
characteristics of this study differ from the geometries considered by [5–7]. In this
study, the Re S from 23,000 to 100,000, h/D varied from 2 to 8. In order to investigate
the curvature effect, they considered S/D in the range 0.29–1.14. Dirita et al. [9] also
carried out numerical investigation similar to the geometry considered by Olsson
et al. [8].