scholarly journals Performance analysis of flat-plate and V-groove solar air collector through CFD simulation

2020 ◽  
Vol 9 (3) ◽  
Author(s):  
Debela Geneti Desisa ◽  
Gadisa Desa Shekata
Keyword(s):  
Flat Plate ◽  
Rough Surface ◽  
Smooth Surface ◽  
Cfd Simulation ◽  
Air Velocity ◽  
Double Pass ◽  
Characteristics Analysis ◽  
Grooved Surface ◽  
Pass Through ◽  
Drying Chamber

The simplicity of solar flat plate air collector and freely availability of solar energy sources attracts attention to collector optimization. This study aims to evaluate the effect of double pass airflow on the performance of flat plate air collectors. Indirect type solar dryer performance characteristics analysis was done through CFD simulation with three different shapes (smooth, rough, and V-grooved) keeping the collector insulated and drying chamber act as a vertical chimney. The average thermal efficiency of the V-grooved surface, smooth surface, and rough surface is 90%, 78%, and 62% respectively. The total area of the collector is 1.20 * 2.0 = 2.60 m2 with the drying cabinet 1.20 * 0.65 * 1.00 m (width * depth * height) and 0.005m thick glass cover. Observed pressure drop at the inlet of the drying chamber is high in the case of smooth surface, medium in a rough surface, and low in a v-grooved plate that will allow enough gas pressure to pass through all the compartment of the process at full-scale. The air mass flow rate is the most important and effective factor during drying. The humidity of the air, as well as air velocity, is also an important factor for improving the drying rate.

scholarly journals PEMANFAATAN KOLEKTOR SURYA SEBAGAI ENERGI ALTERNATIF DESALINASI AIR LAUT UNTUK MENGATASI KRISIS AIR BERSIH

2017 ◽  
Vol 7 (2) ◽  
pp. 59
Author(s):  
Dedet Hermawan Setiabudi ◽  
Muhrom Khudhori
Keyword(s):  
Flat Plate ◽  
Fresh Water ◽  
Heat Pump ◽  
Flow Rate ◽  
Sea Water ◽  
Solar Air Heater ◽  
Air Velocity ◽  
Double Pass ◽  
Air Heater ◽  
Solar Desalination

This research examined the effect of air velocity and the efficiency of double-pass flat plate solar air heater with two glass covers on the performance of solar desalination unit based on heat pump with using humidification and dehumidification processes. This unit consists of a heat pump, humidifier, dehumidifier, and double-pass flat plate solar air heater with two glass covers. The research was conducted in an indoor experiment. Solar energy generated from solar simulator using halogen lamps. In this research the air flow rate was varied at 3 metres per second, 4 metres per second, 5 metres per second, and 6 metres per second, while the intensity of solar radiation at 828 Watts per meter squared. At each variation in air velocity, sea water temperature was conditioned at a constant temperature of 45 degrees celcius, the compressor was operated at a constant rotation of 900 rpm, volumetric flow rate of sea water inlet 300 liters per hour into humidifier and sea water in this system was re-circulated. The research result showed that the volume of fresh water production increases with increasing air velocity inlet into humidifier. This solar desalination unit could produce fresh water maximum 2470 milliliters per hour in air velocity 6 metres per second.

Film cooling characteristics on a grooved surface with different injection orientation angles

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Peng Yang ◽  
Guangchao Li ◽  
Jianyong Zhu
Keyword(s):  
Flat Plate ◽  
Film Cooling ◽  
Orientation Angle ◽  
Hole Injection ◽  
Blowing Ratio ◽  
Reverse Trend ◽  
Grooved Surface ◽  
Shaped Hole

Abstract The film effectiveness was investigated on a grooved surface with the injection orientation angles of 30°, 90°, and 150° at the blowing ratios of 0.5, 0.8, 1.1, and 1.4. The injection orientation angle and the groove on the surface caused the effect of the various and irregular shaped hole injection due to the different orientation injection. The results showed that the new phenomenon of film effectiveness distributions was found on the grooved surface compared with the flat plate case. Film effectiveness distributions for the β = 30° were found to be the discontinuous strips. The surface averaged film effectiveness with the orientation angle of 30° was found to decrease with the increase of the blowing ratio. Additionally, the reverse trend was observed with the orientation angle of 150°. The film effectiveness with the orientation angle of 90° only slightly changed with the increase of the blowing ratio.

Film cooling characteristics on a grooved surface with different injection orientation angles

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Peng Yang ◽  
Guangchao Li ◽  
Jianyong Zhu
Keyword(s):  
Flat Plate ◽  
Film Cooling ◽  
Orientation Angle ◽  
Hole Injection ◽  
Blowing Ratio ◽  
Reverse Trend ◽  
Grooved Surface ◽  
Shaped Hole

AbstractThe film effectiveness was investigated on a grooved surface with the injection orientation angles of 30°, 90°, and 150° at the blowing ratios of 0.5, 0.8, 1.1, and 1.4. The injection orientation angle and the groove on the surface caused the effect of the various and irregular shaped hole injection due to the different orientation injection. The results showed that the new phenomenon of film effectiveness distributions was found on the grooved surface compared with the flat plate case. Film effectiveness distributions for the β = 30° were found to be the discontinuous strips. The surface averaged film effectiveness with the orientation angle of 30° was found to decrease with the increase of the blowing ratio. Additionally, the reverse trend was observed with the orientation angle of 150°. The film effectiveness with the orientation angle of 90° only slightly changed with the increase of the blowing ratio.

scholarly journals Design And Analysis of Flat Plate Solar Air Dryer

2020 ◽  
Vol 7 (1) ◽  
pp. 37-40
Author(s):  
Arunprasad S ◽  
Saravanan P ◽  
Arulraj R
Keyword(s):  
Solar Radiation ◽  
Solar Energy ◽  
Flat Plate ◽  
Basic Function ◽  
Insulation Material ◽  
Ansys Software ◽  
Heated Air ◽  
Moisture Extraction ◽  
Air Dryer ◽  
Drying Chamber

Solar dryers are equipment and using solar energy for drying substances, especially food. There are two common types of solar dryers: Direct & indirect. This is a dryer type in which the product to be dried directly absorbs the solar radiation. It is also referred to as a natural convection cabinet dryer, because the solar radiation falls directly on the surface; the product quality is reduced. Heated air from the drying chamber is blown through. A solar dryer's basic function is to heat air with solar energy to a constant temperature, which enables the moisture extraction from crops within a drying chamber. The main objective of flat plate solar air dryer model based on without tray & with tray chamber in Creo parametric software & computational fluid dynamics in Ansys software. Generally, solar air dryer is heat loss is possible, so it’s reduced with help of insulation material (glass wool & polyurethane). To predict the temperature difference in various air flow with insulation material. Furthermore, choose the better insulation material & difference between with & without tray chamber.

scholarly journals Performance Evaluation of Shell-and-Tube Heat Exchanger with 3-Fluid Sets using CFD and NTU

2019 ◽  
Vol 9 (1) ◽  
pp. 1416-1420
Keyword(s):  
Heat Exchanger ◽  
Industrial Development ◽  
Cfd Simulation ◽  
Sea Water ◽  
Raw Water ◽  
Power Sector ◽  
Tube Heat Exchanger ◽  
Shell And Tube ◽  
Pass Through ◽  
Good Agreement

Energy generation to the present growing population is a crucial challenge for the power sector. Heat exchangers (HE) plays an important role in the industrial development. In this present work an attempt is made to develop a Shell-and- Tube Heat Exchanger (STHE) with segmental baffles using commercial CATIA V5 and Autodesk CFD Simulation Softwares. TEMA standards are considered for design of STHE with baffle-cut of 25%. 3-different sets of fluids are allowed to pass through the shell and tube sides i.e. Methanol - Sea Water (M-S), Distilled Water – Raw Water (D-R) and Kerosene- Crude Oil (K-C). The boundary conditions imposed for analysis are fluid inlet temperatures and velocities. ϵ-NTU is employed for the validation of simulation results and found good agreement between them. Results are plotted for temperature, pressure and velocity contours. The performance of the STHE is shown best for the K-C fluid set among other fluid sets.

Effective boundary conditions for Stokes flow over a rough surface

1996 ◽  
Vol 316 ◽  
pp. 223-240 ◽  
Author(s):  
Kausik Sarkar ◽  
Andrea Prosperetti
Keyword(s):  
Rough Surface ◽  
Stokes Flow ◽  
Smooth Surface ◽  
Traction Force ◽  
Slip Condition ◽  
Partial Slip ◽  
Ensemble Averaging ◽  
Effective Boundary ◽  
Exact Boundary ◽  
Effective Boundary Conditions

Ensemble averaging combined with multiple scattering ideas is applied to the Stokes flow over a stochastic rough surface. The surface roughness is modelled by compact protrusions on an underlying smooth surface. It is established that the effect of the roughness on the flow far from the boundary may be represented by replacing the no-slip condition on the exact boundary by a partial slip condition on the smooth surface. An approximate analysis is presented for a sparse distribution of arbitrarily shaped protrusions and explicit numerical results are given for hemispheres. Analogous conclusions for the two-dimensional case are obtained. It is shown that in certain cases a traction force develops on the surface at an angle with the direction of the flow.

Effects of Friction on Contact of Transverse Ground Surfaces

1994 ◽  
Vol 116 (3) ◽  
pp. 430-437 ◽  
Author(s):  
J. B. Mann ◽  
T. N. Farris ◽  
S. Chandrasekar
Keyword(s):  
Rough Surface ◽  
Contact Pressure ◽  
Smooth Surface ◽  
Bulk Material ◽  
Elastic Half Space ◽  
Material Surface ◽  
Asperity Contact ◽  
Hertz Contact ◽  
Effective Stresses ◽  
Subsurface Stress

The two-dimensional plane-strain sliding contact of a smooth rigid roller on a transverse ground rough surface is analyzed. The rough surface is idealized as an elastic half-space with periodic roughness modeled as cylindrical ridges oriented transverse to the sliding direction. The contact problem is solved using a numerical iterative method in which each asperity contact is treated as a micro-Hertz contact, and the exact treatment of asperity interaction is included. The subsurface stress field is calculated using Westergaard stress functions. The subsequent analysis compares the rough surface stress fields with the corresponding smooth Hertz contact to evaluate the influence of surface roughness and friction on the subsurface stress distributions. The results show that the real area of contact is less than the corresponding smooth surface Hertz contact area, and the magnitude of the actual localized maximum contact pressure is always greater than the corresponding smooth surface contact pressure. The asperity level subsurface effective stresses are greater in magnitude than the maximum subsurface stress due to the macro-Hertz contact for low coefficients of friction, and for high coefficients of friction the maximum effective stresses occur on the bulk material surface.

scholarly journals CFD-Simulation Assisted Design of Elastocaloric Regenerator Geometry

2020 ◽  
Vol 12 (21) ◽  
pp. 9013
Author(s):  
Kristina Navickaitė ◽  
Michael Penzel ◽  
Christian Bahl ◽  
Kurt Engelbrecht ◽  
Jaka Tušek ◽  
...  
Keyword(s):  
Flat Plate ◽  
World Wide ◽  
Cfd Simulation ◽  
Volume Ratio ◽  
Cooling Power ◽  
Promising Alternative ◽  
Compression Cycle ◽  
Elastocaloric Cooling ◽  
Conventional Cooling ◽  
Vapour Compression

Elastocaloric cooling is a promising alternative to conventional cooling using the vapour compression cycle, with potentially higher theoretical exergy efficiency. Nevertheless, there is a number of challenges to be tackled before the technology can be commercially available world-wide. In this study, the potential of double corrugated regenerators to enhance the cooling power of an elastocaloric device that would be operating under compression loading was investigated. The numerical performances of two types of double corrugated geometries are presented and compared to a flat plate regenerator as a reference. The double corrugated geometry significantly increases the surface area to volume ratio and convection of the regenerator, which allows an increase in the power density of the device.

Sign in / Sign up

Export Citation Format

Share Document