scholarly journals Experimental Study of Artificial Solar Air Heater Using Trapezoidal Wave Plate

2019 ◽  
Vol 4 (2) ◽  
pp. 135-148
Author(s):  
Lohdy Diana ◽  
Arrad Ghani Safitra ◽  
Muhammad Syarifuddin Firmansyah ◽  
Mishbaakhus Prana Zinedine

A solar air heater is needed for the drying process, especially in Indonesia.  It means the researches to produce a solar air heater that had high performance is necessary. This research analyses the performance of solar air heater using trapezoidal absorber plate with variation of folded angle 83˚, 85˚, and 87˚. The research carry out artificial experimentally using halogen lamp as a solar simulator. The working principle of solar air heating begins with an induction fan sucking air to enter through the honeycomb then flowing into the air heating duct. The process of heat transfer occurs in a halogen heat lamp passed by the transparent glass and then absorbed by the absorbent plate. This heat will heat the air flowing in the air heating pipe to be transmitted into the drying cupboard. The experiment used several variations of the mass airflow rate 0.022 until 0.051 kg/s and intensity 850, 900, dan 950 W/m2. Temperature measurement is carried out by installing a thermocouple at several points that have been determined. The best performance produced by the wave plate-shaped trapezoidal wave heaters 83˚ when I = 950 W/m2 air mass flow rate 0.022 kg/s with the temperature of the absorbent plate 87 ˚C, the temperature of the exit air 43.2 ˚C, the difference in the rise in air temperature 15.2 ˚C, and when I = 950 W/m2 air mass flow rate 0.051 kg/s the useful heat generated by the air heater 527 Watt, and thermal efficiency 96.8%.

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Satyender Singh ◽  
Prashant Dhiman

The present work intended to investigate thermal and thermohydraulic efficiencies of two different models of recyclic double pass packed bed solar air heaters experimentally. Model-I consists of single air pass through two glass covers as well as double air pass caused due to recycle of the air exiting from the packed bed duct formed between the absorber plate and the glass cover through another duct integrated between the absorber and back plates to inlet of the packed bed duct. On the other hand, model-II consists of only double air pass originated due to recycle operation constituted between the similar solar air heater elements as that of model-I. Twelve numbers of wire mesh screens to form 95% bed porosity were used. Both solar air heater models were tested under the range of packed bed Reynolds number from 300 to 1500 for air mass flow rate and recycle ratio of 0.01 kg/s to 0.025 kg/s and 0.3 to 1.8, respectively. Results revealed that thermal performance of model-I is found to be 15% higher than that of model-II. The optimum value of the recycle ratio for model-I and model-II are obtained as 0.9 and 1.2, respectively, at a mass flow rate of 0.025 kg/s that yields the best thermohydraulic efficiency of 77% and 67%, respectively. Moreover, optimum solution for recycle ratio and air mass flow rate during off sun shine hours are also obtained and presented in the current work.


Solar air heater is a major component of solar dryer. A model of multi pass solar air heater (MPSAH) with reversed absorber and reflector was developed. Exhaustive Study over the performance of MPSAH with and without reversed absorber and cost analysis was done. The performance curves show the effect of solar intensity on MPSAH with and without reversed absorber at constant mass flow. It was observed that the thermal efficiency of MPSAH is depending on solar intensity and losses when mass flow rate remain constant. At constant mass flow rate 26.90 gm/sec, the collector efficiency increased by 9% at average solar intensity 457w/m². Theoretical and experimental analysis showed close agreement. In addition the cost-effectiveness model has been used to examine the performance MPSAH with and without reverse absorbers. The air heaters annual cost (AC) estimation and annual power acquirement (AG) was analyze. The result is evidence for that multi-pass solar air heater with reverse absorbers and reflector is more cost-effective than multi-pass solar collectors without reverse absorber.


2018 ◽  
Vol 7 (1) ◽  
pp. 59 ◽  
Author(s):  
Mohammad Hossein Ahmadi ◽  
Mohammad Ali Afshar ◽  
Ali Naseri ◽  
Mokhtar Bidi ◽  
H. Hadiyanto

The aim of this study is modeling a solar-air heater humidification-dehumidification unit with applying particle swarm optimization to find out  the maximum gained output ratio with respect to the mass flow rate of water and air entering humidifier, mass flow rate of cooling water entering dehumidifier, width and length of solar air heater and terminal temperature difference (TTD) of dehumidifier representing temperature difference of inlet cooling water and saturated air to dehumidifier as its decision variable. A sensitivity analysis, furthermore, is performed to distinguish the effect of operating parameters including mass flow rate and streams’ temperature. The results showed that the optimum productivity decreases by decreasing the ratio of mass flow rate of water entering humidifier to air ones.Article History: Received: July 12th 2017; Revised: December 15th 2017; Accepted: 2nd February 2018; Available onlineHow to Cite This Article: Afshar, M.A., Naseri, A., Bidi, M., Ahmadi, M.H. and Hadiyanto, H. (2018) Modeling and PSO Optimization of Humidifier-Dehumidifier Desalination. International Journal of Renewable Energy Development, 7(1),59-64.https://doi.org/10.14710/ijred.7.1.59-64


2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Seyyed Mahdi Taheri Mousavi ◽  
Fuat Egelioglu

The thermal performances of three slit-glazed solar air heaters (SGSAHs) were investigated experimentally. Three SGSAHs with different bed heights (7 cm, 5 cm, and 3 cm) were fabricated with multiple glass panes used for glazing. The length, width, and thickness of each pane were 154 cm, 6 cm, and 0.4 cm, respectively. Ambient air was continuously withdrawn through the gaps between the glass panes by fans. The experiments were conducted for four different gap distances between the glass panes (0.5 mm, 1 mm, 2 mm, and 3 mm) and the air mass flow rate was varied between 0.014 kg/s and 0.057 kg/s. The effects of air mass flux on the outlet temperature and thermal efficiency were studied. For the SGSAH with bed height of 7 cm and glass pane gap distance of 0.5 mm, the highest efficiency was obtained as 82% at a mass flow rate of 0.057 kg/s and the air temperature difference between the inlet and the outlet (∆T) was maximum (27°C) when the mass flow rate was least. The results demonstrate that for lower mass flow rates and larger gaps, the performance of SGSAH with a bed height of 3 cm was better compared to that of others. However, for higher mass flow rates, the SGSAH with 7 cm bed height performed better.


2021 ◽  
Vol 39 (5) ◽  
pp. 1649-1658
Author(s):  
Subhash Chand ◽  
Prabha Chand

The aim of the present study to improve the performance of solar air heater because of low thermo-physical properties of air. In the current work, an attempt has been made to improve the performance of the heater by employing louvered fins to the absorber plate, as it not only enhances heat transfer coefficient but also improve heat transfer area. The effect of exergy performance on the geometrical parameters of louvered fin i.e., louvered angle, louvered pitch and louvered length has been studied and analyzed. The results are compared to plane solar air heater (PSAH) to evaluate the effectiveness of louvered finned solar air heater (LFSAH). The exergy efficiency of LFSAH is comparatively higher for all the operating conditions except for higher mass flow rate where it may even go below that of PSAH; possibly due to the higher pressure drop and more loss of exergy at high mass flow rate. In addition, the results conclude that for louvered parameters viz., louvered angle 20°, fin pitch to louvered pitch ratio 0.75 and louvered length to louvered pitch ratio 1.25, high exergy performance of SAH is obtained as compared to other louvered parameter values.


2020 ◽  
Vol 8 (6) ◽  
pp. 3221-3225

This work deals with the analysis of the proposed innovative humidification-dehumidification (HD) desalination unit in which waste hot air of kitchen chimney has been used for heating brackish water. The proposed system is configured with solar air heater also, thus both heated air and heated water has been used to improve the water yield of desalination unit compared to conventional system. Mathematical modeling of propose unit based on energy balance of flat plate air heater, humidifier, dehumidifier and brackish water tank has been used to evaluate the effect of operating condition. Potable water yield found to increase (with highest productivity of 6.5 kg/day) when mass flow rate of process air increases from 0.6 kg/min to 3 kg/min. Strong dependency of water mass flow rate has also been found as productivity increases (with maximum value of 6.7 kg/day and 7.5 kg/day) by increasing the mass flow rate of brackish water in humidifier and cold water in dehumidifier respectively. The higher initial temperature of brackish water also found beneficial as it increases productivity. Finally, the thermal performance of desalination unit has been evaluated in terms of Gain in Output Ratio and comparison has been made with conventional system. The higher GOR of the proposed system ensures the better utilization of thermal energy in potable water production.


Author(s):  
Bhawna Agrawal ◽  
Pallavi Agrawal ◽  
Suman Agrawal

This paper focuses on Mathematical Modelling of Single Glazed and Double Glazed Solar air heater (SAH) which is special kind of heat exchanger that transfers thermal energy from the solar radiation to the fluid flowing inside of the collector. The most potential applications of SAH is the supply of hot air for heating of buildings, to maintain a comfortable environment especially in the winter season, air preheating, desiccant refrigeration, and drying of vegetables, fruits, meat, textile and marine products. Solar radiation intensity is less in the morning that increase gradually till noon and again decrease from noon to evening. During simulations it is observed that the heat gain is directly proportional to the mass flow rate. It is maximum for the counter flow SAH and is least for transpired solar air heater. The efficiency of the SAH is directly proportional to mass flow rate. The thermal efficiency is maximum for the counter flow SAH, The useful heat gain increases is highest in the clear days of summer month particularly in the month of April-May and lowest in the cloudy days of winter month particularly in the month of December. The results are in conformation with theoretical aspects.


2021 ◽  
Vol 3 (2) ◽  
pp. 49-55
Author(s):  
Atul Kumar ◽  
Prabhakar Bhandari ◽  
K.S. Rawat

This paper presents a theoretical investigation of solar air heater using phase change material (PCM). PCM used in present configuration is homogenous mixture of paraffin wax with Aluminium powder. The purpose of using Aluminium powder with paraffin wax is to increase the thermal conductivity. PCM mixtures are encapsulated in cylinders and are used as solar absorbers. Using MATLAB program, the effect of different parameters is studied. It has been observed that with increase in mass flow rate, air outlet temperature decreases and freezing time of cylinder decreases. However, at constant mass flow rate, with increase in cylinder radius, air temperature decreases and while freezing time increase sharply. The different parameters have  to be chosen such that performance of solar air heater can be optimized.


Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1415 ◽  
Author(s):  
Yu Wang ◽  
Mikael Boulic ◽  
Robyn Phipps ◽  
Manfred Plagmann ◽  
Chris Cunningham

This study investigates the thermal efficiency of a solar air heater (SAH), when it was mounted on a custom-made support frame, and was operated under different air mass flow rate. This SAH is composed of a transparent polycarbonate cover plate, a felt absorber layer, a perforated aluminium back plate and an aluminium frame. The ambient inlet air of this SAH is heated as it passes through the perforated back plate and over the felt absorber layer. The heated air is blown out through the outlet. Studies of SAHs with a similar design to this SAH were not found in the literature. The experiment was carried out at Massey University, Auckland campus, NZ (36.7° S, 174.7° E). The global horizontal solar irradiance, the ambient temperature and the wind speed were recorded using an on-site weather station. Temperature and velocity of the air at the outlet were measured using a hot wire anemometer. During the experiment, the air mass flow rate was between 0.022 ± 0.001 kg/s and 0.056 ± 0.005 kg/s. Results showed that when the SAH was operated at the airflow between 0.0054 kg/s and 0.0058 kg/s, the inlet air temperature and the wind speed (between 0 and 6.0 m/s) did not impact the temperature difference between the outlet air and the inlet air. The thermal efficiency of the SAH increased from 34 ± 5% at the airflow between 0.021 kg/s and 0.023 kg/s, to 47 ± 6% at the airflow ranging from 0.032 kg/s to 0.038 kg/s, to 71 ± 4% at the airflow of 0.056 ± 0.005 kg/s. The maximum thermal efficiency of 75% was obtained at the airflow of 0.057 kg/s. The effective efficiency of the SAH was 32 ± 5% at the airflow between 0.021 kg/s and 0.023 kg/s, 42 ± 6% at the airflow ranging from 0.032 kg/s to 0.038 kg/s, and 46 ± 11% at the airflow of 0.056 ± 0.005 kg/s.


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