scholarly journals Heat Transfer Analysis and Performance Measurements of Hollow Pin-fin in Natural Convection

2019 ◽  
Vol 8 (6S) ◽  
pp. 727-731
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Temperature Distribution ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Thermal Performance ◽  
Temperature Drop ◽  
Heat Transfer Analysis ◽  
Pin Fin ◽  
And Performance

The Fin act as dissipiating elements, selection of proper geometry plays crusial role in increasing the rate of heat transfer and performance of the system. This work has been undertaken to investigate and compare thermal performance of solid and hollow pin-fin. Heat transfer analysis of solid and hollow pin fin carried and the results was compared with the experimental results. experiment was conducted to analyze the natural convection around solid hollow pin fin, and compare thermal performance of hollow pin fin with the solid pin fin of same dimension and orientation. The experimental result of temperature distribution shows that the faster temperature drop along the length. The high value of convective heat transfer in the initial phase due to which faster temperature drop takes place. Convection is found to be dominating due to less area for conduction along the length. Theoretical value and experimental value are close to each for temperature distribution as well the convective heat transfer coefficient. Efficiency is reduced in the case of hollow fin but the effectiveness of the hollow pin fin is increased by 1.76 times from an economical point of view, holoow pin fin is more efficient solution.

A Theoretical Investigation Into the Optimal Longitudinal Profile of a Horizontal Pin Fin of Least Material Under the Influence of Natural Convection

2005 ◽  
Author(s):  
Chris J. Kobus
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Natural Convection ◽  
Transfer Coefficient ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Convective Heat Transfer Coefficient ◽  
Maximum Heat ◽  
Pin Fin ◽  
Special Cases

Fundamental level research is presented in this paper discovering the optimum pin fin profile maximizing material utilization (maximum heat transfer with minimum volume) in the case of natural convection. Although this problem has been studied in the past, the current research allows for an axially variable convective heat transfer coefficient due to the axially variable diameter in such pin fins. The current model is compared with previous studies assuming a constant convective heat transfer coefficient. The comparison shows the prior solutions to be special cases of the model in the current research.

The Effect of Thermal Wall Properties on Natural Convection in Inclined Rectangular Cells

1982 ◽  
Vol 104 (1) ◽  
pp. 111-117 ◽  
Author(s):  
B. A. Meyer ◽  
J. W. Mitchell ◽  
M. M. El-Wakil
Keyword(s):  
Heat Transfer ◽  
Cell Wall ◽  
Natural Convection ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Conductive Heat ◽  
Numerical Work ◽  
Aspect Ratios ◽  
Convection Problem ◽  
Natural Convection Problem

The effects of cell wall thickness and thermal conductivity on natural convective heat transfer within inclined rectangular cells was studied. The cell walls are thin, and the hot and cold surfaces are isothermal. The two-dimensional natural convection problem was solved using finite difference techniques. The parameters studied were cell aspect ratios (A) of 0.5 and 1, Rayleigh numbers (Ra) up to 105, a Prandtl number (Pr) of 0.72 and a tilt angle (φ) of 60 deg. These parameters are of interest in solar collectors. The numerical results are substantiated by experimental results. It was found that convection coefficients for cells with adiabatic walls are substantially higher than those for cells with conducting walls. Correlations are given for estimating the convective heat transfer across the cell and the conductive heat transfer across the cell wall. These correlations are compared with available experimental and numerical work of other authors.

scholarly journals Mathematics Modelling and Performance Analysis of the Heat Transfer on Vacuum Tube Collector of Water Heater Application

2020 ◽  
Vol 190 ◽  
pp. 00022
Author(s):  
Lia Hamanda ◽  
Gunawan Nugroho
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Thermal Performance ◽  
Solar Collector ◽  
Dynamic Behaviour ◽  
Tube Axis ◽  
Outdoor Temperature ◽  
Water Heater ◽  
And Performance ◽  
Mathematical Modelling And Simulation

The aim of this work is to study a mathematical modelling and simulation for predicting the thermal performance heat-pipe evacuated a solar collector for water heater, which was considered the temperature distribution along the tube axis and radius. This model used to help in studying the dynamic behaviour of the system design and the effect of influential parameter on the water heater process. The result showed that water heating is affected by the surface of collector, metrological conditions such as solar radiation and outdoor temperature, even the thermal performance of the collector.

scholarly journals CONVECTIVE HEAT TRANSFER ANALYSIS IN AN ARCH ENCLOSURE

2015 ◽  
Vol 6 (1) ◽  
Author(s):  
Manoj Kumar Triveni ◽  
Dipak Sen ◽  
RajSekhar Panua
Keyword(s):  
Heat Transfer ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Heat Transfer Analysis

Investigations on Transient Natural Convection in Boron Nitride-Mineral Oil Nanofluid Systems

2012 ◽  
Author(s):  
Shijo Thomas ◽  
C. B. Sobhan ◽  
Jaime Taha-Tijerina ◽  
T. N. Narayanan ◽  
P. M. Ajayan
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Heat Transfer Coefficient ◽  
Natural Convection ◽  
Boron Nitride ◽  
Transfer Coefficient ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Convective Heat Transfer Coefficient ◽  
Mineral Oil

Nanofluids are suspensions or colloids produced by dispersing nanoparticles in base fluids like water, oil or organic fluids, so as to improve their thermo-physical properties. Investigations reported in recent times have shown that the addition of nanoparticles significantly influence the thermophysical properties, such as the thermal conductivity, viscosity, specific heat and density of base fluids. The convective heat transfer coefficient also has shown anomalous variations, compared to those encountered in the base fluids. By careful selection of the parameters such as the concentration and the particle size, it has been possible to produce nanofluids with various properties engineered depending on the requirement. A mineral oil–boron nitride nanofluid system, where an increased thermal conductivity and a reduced electrical conductivity has been observed, is investigated in the present work to evaluate its heat transfer performance under natural convection. The modified mineral oil is produced by chemically dispersing boron nitride nanoparticles utilizing a one step method to obtain a stable suspension. The mineral oil based nanofluid is investigated under transient free convection heat transfer, by observing the temperature-time response of a lumped parameter system. The experimental study is used to estimate the time-dependent convective heat transfer coefficient. Comparisons are made with the base fluid, so that the enhancement in the heat transfer coefficient under natural convection situation can be estimated.

Influence of Short Helical Tape on Local Convective Heat Transfer and Thermal Performance Characteristics in Turbulent Decaying Swirl Flow

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Smith Eiamsa-ard ◽  
Vichan Kongkaitpaiboon ◽  
Khwanchit Wongcharee
Keyword(s):  
Heat Transfer ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Thermal Performance ◽  
Swirl Flow ◽  
Transfer Rates ◽  
Friction Factors ◽  
Plain Tube ◽  
Uniform Wall ◽  
Uniform Wall Heat Flux

This paper reports the experimental investigation of local convective heat transfer enhancement, flow friction and thermal performance factor behaviors in the tube fitted with the short helical tapes (SHTs) acting as decaying swirl flow generators. The tapes with three different helical tape angles (? = 90°, 135° and 180°) and three different channel numbers (N = 2, 3 and 4 channels) were tested under the uniform wall heat flux condition. The performance of each tape is compared with the performance of the plain tube subject to the same pumping power. The experimental results show that the heat transfer rates and friction factors of the tube with SHTs are respectively in range of 1.15 to 1.9 and 1.49 to 2.31 times of those in the plain, corresponding to thermal performances between 0.98 and 1.46. The correlations for Nusselt number (Nu) as a function of Reynolds number (Re), Prandtl number (Pr), helical tape angle (?) and the number of channel (N) are also developed.

Sign in / Sign up

Export Citation Format

Share Document