Transportation sector is the important sector and consumed the most fossil fuel in the world. Since COVID-19 started in 2019, this sector had become the world connector because every country relies ...on logistics. The transportation sector does not only deal with the human transportation but also relates to logistics. Research in every country has searched for alternative transportation to replace internal combustion engines using fossil fuel, one of the most prominent choices is fuel cells. Fuel cells can use hydrogen as fuel. Hydrogen can be fed to the fuel cells to provide electric power to drive vehicles, no greenhouse gas emission and no direct combustion required. The fuel cells have been developed widely as the 21st century energy-conservation devices for mobile, stationary, and especially vehicles. The fuel cell electric vehicles using hydrogen as fuel were also called hydrogen fuel cell vehicles or hydrogen electric vehicles. The fuel cells were misconceived by several people that they were batteries, but the fuel cells could provide electric power continuously if their fuel was provided continuously. The batteries could provide electric power as their only capacities, when all ions are released, no power could be provided. Because the fuel cell vehicles play important roles for our future transportation, the overall review for these vehicles is significantly interesting. This overall review can provide general and technical information, variety of readers; vehicle users, manufacturers, and scientists, can perceive and understand the fuel cell vehicles within this review. The readers can realize how important the fuel cell technologies are and support research around the world to drive the fuel cell vehicles to be the leading vehicles in our sustainable developing world.
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•Fuel cells use hydrogen as fuel to provide electric power.•Fuel cells do not emit greenhouse gas and do not require direct combustion.•The fuel cell electric vehicles (FCEVs) are one of the zero emission vehicles.•Fuel cell technology has been developed for many types of vehicles.•Hydrogen production, transportation, storage and usage links play roles on FCEVs.
Global temperatures have raised because of phenomena such as Greenhouse effect and Global warming. Theses phenomena affect primary producers; plants, on earth. As health issues become significant in ...Thai society, variety types of healthy food are available in Thai markets, Sunflower sprouts are sold among them. The controlled room or greenhouse became needier in plantation and seedling because air temperatures and humidity can be adjusted and controlled to suit plants inside the greenhouse, the temperatures in the greenhouse could be reduced from 2 to 10 Celsius and relative humidity could be arranged from 70 to 99%RH. This work focused on utilizing the greenhouse installed with the developed temperature and humidity controller in sunflower seedling for income earning in a community. A new temperature and humidity controller including sensors was designed and fabricated to control conditions inside the greenhouse based on Arduino technology with a low fabrication cost and easy to program as well as maintenance. The greenhouse investigation was performed by using three different sunflower seedling nutrient solutions which were affordable and locally available solutions; a commercial nutrient solution, solutions prepared from cattle and earthworm manure bio-extracts, and three different seedling materials; cotton balls, coconut coir and loam. The greenhouse was set 4 Celsius lower than ambient temperatures and temperature and different relative humidity values compared with the ambient air were set to be between 25 and 35%RH, the greenhouse performance in this work was indicated by sunflower sprout germination percentage and germination index. From the experimental results, the maximum sunflower sprout germination percentage at 91.11% and the maximum germination index at 13.98 were obtained when the sunflower seeds were grown in the coconut coir with the solution prepared from earthworm manure bio-extracts, the higher germination percentage than that of a literature. The greenhouse with the developed in-house temperature and humidity controller has proved its performance in seedling sunflower sprouts and this feasibility study has shown that it had potentiality to be used in a household seedling application.
During sugarcane harvesting process on fields, there were sugarcane losses occurred in the process such as blown-out loss from a primary extractor fan used to clean leaves out of the sugarcane, loss ...from conveyers and from high cutting by a base cutter. Different species of sugarcane (Saccharum officinarum L.) contained different trunk and leaf sizes, different cleaning fan speeds should be considered. If the losses are reduced, the better process can be obtained, and farmers get more income from more products and less loss. This work focused on finding the proper operating speeds of the primary extractor fan equipped in the sugarcane harvester; A8000/8800 model CASE IH trademark, to harvest the Khon Kaen 3 (KK 3) sugarcane (S. officinarum L.) in the minimum contamination and by the maximum flawed sugarcane sticks less than 2%. The harvester manufacturer has recommended the fan speed at 800 rpm as the suggested speed. The experimental investigations in five different operating speeds; 700, 800, 900, 1000 and 1100 rpm, of the fan were performed at the sugarcane field in Saybouly District, Kenghat Village, Lao PDR. Ten different sampling points were specified to check contamination; sand, leaves and flawed sugarcane sticks, along 400-meter-long plots with 1.65-meter plot offset. Each sampling point was in a 10-meter-square area. The reported values were average values obtained from all points in three repeating examinations. We found that the minimum contamination was 7.26% and the flawed sugarcane was 1.95% when the fan speed at 700 rpm. The maximum contamination was at the highest speed. Therefore, the fan speed at 700 rpm was used as the new operating speed for the harvester in the KK 3 sugarcane harvesting process to reduce the losses.
Nanofluids are considered to offer important advantages over conventional heat transfer fluids. Over a decade ago, researchers focused on measuring and modeling the effective thermal conductivity and ...viscosity of nanofluids. Recently important theoretical and experimental research works on convective heat transfer appeared in the open literatures on the enhancement of heat transfer using suspensions of nanometer-sized solid particle materials, metallic or nonmetallic in base heat transfer fluids. The purpose of this review article is to summarize the important published articles on the enhancement of the forced convection heat transfer with nanofluids.
Nanofluids have shown their advantages and potentials in improving heat transfer rates when the nanofluids are applied as working fluids in thermal systems. Researcher groups concentrating on the ...nanofluids have increased continuously and focused deeply into various fields; theoretically, experimentally and numerically. This review summarized the important published works on nanofluid preparations, properties, experimental and numerical heat transfer behaviors. In the simulations, two main categories were discussed in detail as the single-phase modeling which the combination of nanoparticle and base fluid is considered as a single-phase mixture with steady properties and the two-phase modeling which the nanoparticle properties and behaviors are considered separately from the base fluid properties and behaviors.
The Development of Rotating Rice Grain Dryer Prototype PRAMUANJAROENKIJ, ANCHASA; TONGKRATOKE, AMARIN; PHANKHOKSOONG, SIRILUK
International Journal of Environmental and Rural Development,
2019, Volume:
10, Issue:
1
Journal Article
Peer reviewed
Open access
This research focused on the development of the rotating rice grain dryer prototype for Germinated Parboiled Brown Rice (GPBR) grains. The main GPBR producer in this study was Baan Dong Luang ...community enterprise, Bung Tawai Sub-District, Tao Ngoi District, Sakon Nakhon Province, Thailand. The producer needs to reduce paddy moistures from above 20% wb down to 15% wb as the packaging and buyer requirements. The original prototype was designed to utilize heat from only the sunlight. It consisted of the driving part, the base and frame and the dryer chamber, which was a smooth-inside-area stainless steel cylinder. In this work, five aluminum fins were installed inside the cylinder to increase the grain distributions. The grain-collecting tray and wheels were attached to the prototype. Experimental investigations were performed repeatedly; 3 times. From the experimental results, the grain distributions observed from the developed prototype were better those from the original prototype. The tray could facilitate the users in taking the dehumidified grains out. The wheels made the prototype movable, the developed prototype could be moved to take the sunlight more convenient. The noticeable experimental result was the drying performance of the developed prototype. The developed prototype took 3 hours to reduce the paddy moistures down to 15% wb while the original prototype could reduce the paddy moistures down within 4.5 hours. On the other hand, the fins could distribute the grains, the heat transfer inside the chamber was enhanced. The reduced drying period was about 33.33%. As the rice dryer is an important tool in household and community rice producers, this dryer prototype could be proved to reduce the drying areas, periods and labors which affects the net incomes of farmers. The famers satisfied with the developed prototype.
Global warming situation has affected many life in the world; especially its effects on agricultural industry. Greenhouse was one of many tools which was brought to help farmers in growing many ...plants and flowers in uncontrollable environments for long time. This work was aimed to build a low-cost controlled temperature greenhouse prototype. The greenhouse prototype was studied for temperature distributions inside the prototype to sow marigold seedlings. A water evaporative cooling system was chosen to remove heat from the greenhouse, a low-cost temperature control set was fabricated to help controlling air flow and temperature inside the greenhouse. A cooling pad system was chosen as the evaporative cooling system in this work. The greenhouse frame was built locally as a length of 2.1 m., a width of 1.8 m. and a height of 3.1 m. and was covered with clear UV reducing plastic. The cooling pad system consisted of 25-watts ventilating fans with a length of 30 cm, a width of 30 cm, a height of 16 cm and one 60-watt water pump. The low-cost temperature control set was connected with the cooling pad system to turn on and off the fan of the system automatically and to remove the humid air out of the greenhouse. Six different seedling materials; pure peat moss, pure bagasse, bagasse mixed with soil at 1:1 and at 1:0.5 by weight, bagasse mixed with soil and rice-straw biochar at 1:1:0.5 and at 1:0.5:0.5 by weight, were also investigated in the greenhouse. The experimental results showed that using one cooling pad could reduce inside temperature with an average temperature different of 2.5 Celsius while using three cooling pads could reduce inside temperature with an average temperature different of 5 Celsius. The air circulation system also affected the temperature distribution inside the greenhouse and could control the temperature inside the prototype. The seedling material which was prepared from bagasse mixed with soil; at a mixing ratio of 1:0.5 by weight, allowed marigold seedling to grow the most in the same experiment period.
The solid oxide fuel cell (SOFC) is one of the most promising fuel cells for direct conversion of chemical energy to electrical energy with the possibility of its use in co-generation systems because ...of the high temperature waste heat. Various mathematical models have been developed for three geometric configurations (tubular, planar, and monolithic) to solve transport equations coupled with electrochemical processes to describe the reaction kinetics including internal reforming chemistry in SOFCs. In recent years, considerable progress has been made in modeling to improve the design and performance of this type of fuel cells. The numbers of the contributions on this important type of fuels have been increasing rapidly. The objective of this paper is to summarize the present status of the SOFC modeling efforts so that unresolved problems can be identified by the researchers.
•The fluctuating storage conditions of the agricultural products must be aware of.•The postharvest storage conditions are critical to product freshness and abundance.•The Double-Pipe Heat Exchangers ...(DPHExs) enhanced the FSC and VSC system performance.•The VSC system coupled with the DPHEx consumed less energy that another couple.•The VSC system coupled with the DPHEx also enhanced the storage condition stability.
In a hot, humid, and fluctuating climate due to global climate change, agricultural postharvest relies prominently on refrigerating systems. To enhance thermal performance, such as in refrigerating systems, heat exchangers can be used. This work focused on expressing the air temperature, air relative humidity, and energy consumption (EC) profiles of two refrigerating storages using the HFC-32 fixed- and variable-speed compressor (FSC and VSC) systems in four experimental investigations. The profiles were recorded before and after the double-pipe heat exchanger (DPHEx) installations. Both storages had heaters, humidifiers, and hot water pots to generate heat and humidity at 18 °C and 22 °C, a storage temperature range for many postharvest products. From the results, both systems performances in reducing the EC of the FSC and VSC systems were enhanced by using the DPHExs. The EC of the FSC and VSC systems were reduced by 52.33 % and 17.19 % at 18 °C and 50.63 % and 20.00 % at 22 °C, respectively. All experiments with storage using the FSC system resulted in fluctuating profiles. This research information provides basic information for preliminary decisions about using DPHExs in postharvest refrigerating systems and selecting systems targeting the FSC and VSC systems in different situations. The power demand and operating cost relating to agricultural product storage can be calculated by using the EC correlation of each cooling system. Product freshness and abundance depend on fluctuating conditions, postharvest storage conditions, temperature, and relative humidity. The VSC system, coupled with the DPHEx, demonstrated enhancements on the EC and stable conditions.