by Nicholas Musembi Maundu, Kosgei Sam Kiptoo, Kiprop Eliud, Dickson Kindole and Yuichi Nakajo
Original Research
In this research work, an indirect natural convection flow updraft solar dryer was studied with objectives to; study air-flow distribution using Particle Image Velocimetry (PIV) technique, analyze relative humidity and humidity ratio variations in relation to temperature, visualize temperature distribution on drying surface and carry out performance analysis of solar dryer. An already existing dryer was modified in order to suit PIV study experiments. The dryer consisted mainly of; hinged flexible angled solar collector, drying chamber consisting of three drying trays and updraft chimney with metallic absorber. The smoke was introduced, by use of an electronic smoker for visualization of distribution of airflow in the drying chamber, and recorded via high speed camera of 30 fps for the purpose of analysis by use of PIV software. Thermal vision camera was used to capture temperature variation images which indicated highest variance of 1.4°C from the mean of the four line sections. For the general performance analysis, experiments were carried out by drying 2.5 mm sliced apples. Temperature and relative humidity of the airflow were taken at the collector inlet, drying chamber inlet and drying chamber outlet using data loggers. Airflow inlet to solar collector and from drying chamber were determined using hot wire anemometers, irradiance (W/m2) was measured using radiation meter. PIV results were achieved indicating fair airflow distribution across the drying bed with high correlation coefficient average at around 0.9 and low velocity standard deviation of below 0.004 in a frame across the sections. Imagery results for Turbulent Kinetic Energy indicated an average of 4.0 x 10-5 m2/s2 which implied a fairly smooth airflow which can be said to be a characteristic of natural convection updraft solar dryer. Experiments conducted on loaded solar dryer showed high uniformity on the dried product across the trays; thus, an indication of good airflow distribution across the drying trays corresponding to PIV results obtained. Fresh apples of moisture content 86% (wet basis) were dried to moisture content of 13.74% (wet basis) within 8 hours 40 minutes; the dryer achieved overall efficiency of 16.49 % at an average horizontal irradiance of 525.29 W/m2. The dried apples were found to have good texture, color and taste.
American Journal of Energy Research. 2017, 5(1), 12-22. DOI: 10.12691/ajer-5-1-2
Pub. Date: March 08, 2017
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by Ghazaleh Abbasian, Mohammadmehdi Moulaii and Seyyed Aliakbar Sadri
Original Research
The impact of technology is obviously perceptible on quality of life in different communities. As they are equipped to keep pace with advances in science and technology, a radical change is occurring in their way of life. Thus, a space to accommodate a wide range of activities must be designed to meet the needs of people. The exponential growth in scientific and technological advancements and the changes in their related needs might not keep up with currently permanent residential spaces. It could gradually hinder the efforts to create a favorable environment and to derive satisfaction. Hence, spatial phenomena necessitate adaptive architectural design to achieve a suitable model for responding to the needs of human societies, especially in residential areas. The space should be held accountable in accord with the demands of users. This important issue is detectable after spending long hours of activity and attending noisy and crowded spaces. Thus, people require places that psychologically bring them peace and tranquility. Spaces that are subject to adapt to the changeable psychological, cultural, and geographic conditions can provide consumers higher quality. This process leads to a sense of belonging to such kind of spaces among more users. Providing people the varied landscape to the exterior would refresh them during tiredness of daily activities, furthermore, such observations can maintain their relationship with outer space in one way or another. As a result, the residential environment should be diversifying and open to change based on individuals’ demands. Flexible architectural systems can promote a sense of satisfaction along with vitality and effectively recharge people to work the next day. Scholarly attention has been focused on the importance of human and his mental-physical needs. These human activities aim at reaching a certain goal in terms of peace, happiness, and satisfaction in worldly life. Using a system that changes its comportment in response to user’s demand in residential areas has a direct impact on stages of human life. By space change based on user’s need, he or she can increase the happiness of being in that space. Regarding the feeling of happiness, the results of this research could have an impact not only on each house but also on society. Using correlational method, interviews were conducted in this field study. Now that technology has had a significant influence on the formation of human needs, the current status of buildings with regard to change requests cannot be maintained any more. As a result, this study adopted the effective strategies to create flexible spaces for residential buildings and private residences.
American Journal of Energy Research. 2017, 5(1), 1-11. DOI: 10.12691/ajer-5-1-1
Pub. Date: February 20, 2017
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