Dry System Research Articles

Analysis of the Influence of Nozzle Structure of Dry Powder Fire Extinguishing System on Supersonic Jet Characteristics

Analysis of the Influence of Nozzle Structure of Dry Powder Fire Extinguishing System on Supersonic Jet Characteristics

Sustainable solar drying: Recent advances in materials, innovative designs, mathematical modeling, and energy storage solutions

The utilization of solar drying technologies has gained increasing importance in the context of sustainable and energy-efficient processes. This exploration delves into current trends in solar drying, specifically focusing on materials, designs, and their integration with energy storage solutions. Within the materials domain, we examine solar collectors, absorbers, and the impactful role of phase change materials (PCMs) in augmenting drying efficiency. Innovative designs and configurations are discussed, offering insights into advanced solar drying systems. Furthermore, the integration of energy storage technologies is highlighted, critical role of energy management in solar drying applications is emphasized. The assessment encompasses performance and efficiency enhancements, including mathematical modeling and the optimization of heat transfer processes. Challenges and potential future directions in solar drying are explored, along with the promising areas for ongoing research. The object is to provide a comprehensive perspective on the recent advancements in solar drying, offering valuable insights for sustainable practices and future developments.

MOVING: A Multi-Modal Dataset of EEG Signals and Virtual Glove Hand Tracking.

Brain-computer interfaces (BCIs) are pivotal in translating neural activities into control commands for external assistive devices. Non-invasive techniques like electroencephalography (EEG) offer a balance of sensitivity and spatial-temporal resolution for capturing brain signals associated with motor activities. This work introduces MOVING, a Multi-Modal dataset of EEG signals and Virtual Glove Hand Tracking. This dataset comprises neural EEG signals and kinematic data associated with three hand movements-open/close, finger tapping, and wrist rotation-along with a rest period. The dataset, obtained from 11 subjects using a 32-channel dry wireless EEG system, also includes synchronized kinematic data captured by a Virtual Glove (VG) system equipped with two orthogonal Leap Motion Controllers. The use of these two devices allows for fast assembly (∼1 min), although introducing more noise than the gold standard devices for data acquisition. The study investigates which frequency bands in EEG signals are the most informative for motor task classification and the impact of baseline reduction on gesture recognition. Deep learning techniques, particularly EEGnetV4, are applied to analyze and classify movements based on the EEG data. This dataset aims to facilitate advances in BCI research and in the development of assistive devices for people with impaired hand mobility. This study contributes to the repository of EEG datasets, which is continuously increasing with data from other subjects, which is hoped to serve as benchmarks for new BCI approaches and applications.

Effects of Yeast-Enriched Functionalized Canola Meal Supplementation on Apparent Total Tract Macronutrient Digestibility and Fecal Characteristics, Fecal Microbiota, and Immune Function of Healthy Adult Dogs.

Brewer's dried yeast has a high nutritional value and has long been utilized by the animal feed industry as a source of protein, B-complex vitamins, and minerals. Brewer's dried yeast is also rich in bioactive compounds and may thereby be used as a functional ingredient, providing benefits beyond that of its nutrient content. Canola meal is a high-fiber ingredient that also has unique properties, especially when it is wetted and dried using a proprietary drying system that creates a "functionalized" canola meal. The objective of this experiment was to evaluate the effects of a yeast-enriched functionalized canola meal (FCM) on apparent total tract digestibility (ATTD) and the fecal quality, metabolite concentrations, and microbiota populations, and immune function of healthy adult dogs. Twelve adult female beagles [body weight (BW) = 7.6 ± 0.7kg; age = 5.8 ± 1.3] were used in a replicated 4×4 Latin square design with 28-d periods. Each experimental period consisted of a 22-d adaptation phase, 5 days of total and fresh fecal collection, and blood collection on the last day. To start, all dogs were fed a basal diet to maintain BW for 14 d. Following fecal and blood collections at baseline (-1 d) to confirm health status, experimental periods began testing the following dietary treatments using a Latin square design experiment: 1) FCM only (no yeast inclusion), 2) FCM + low yeast dose, 3) FCM + medium yeast dose, and 4) FCM + high yeast dose. All treatments were top-dressed onto the basal diet at a rate estimated to be 1% of daily intake (as-is basis). Statistical analysis was performed using the PROC MIXED procedure of SAS with the main effect of treatment and the random effect of dog. Significance was declared at P ≤ 0.05, and trends reported if 0.05 < P ≤ 0.10. Supplementation with yeast-enriched FCM had no significant effect on the ATTD of macronutrients or energy or the fecal characteristics, metabolite concentrations, and microbiota populations of dogs. Additionally, no significant differences were observed in circulating immune cell counts or response to Toll-like receptor agonists among treatments. Our results suggest that the yeast-enriched FCM could be included in canine diets without negatively affecting stool quality, fecal metabolite concentrations, or ATTD. Further research is necessary to determine the effective dose of yeast-enriched FCM, potential mechanisms of action, and other potential implications it has on canine health.

Energy and exergy analysis for a laboratory-scale closed-loop spray drying system: Experiments and simulations

Improving exergy efficiency is crucial to the drying process, especially in reducing costs and carbon dioxide emissions. A closed-loop drying system with a condenser-reheater system was built and analyzed using a numerical simulation to explore the optimal drying conditions, such as inlet air temperature and the air flow rate. Heat-loss coefficients in the simulation were fitted to experimental measurements. The study found that increasing the inlet temperature led to an increase in energy inflow and exergy loss in the system. With an increase in air flow rate from 0.005 to 0.01 kg/s, the exergy loss of the chamber decreased (0.07–0.04 kW), and the exergy efficiency increased (69–92%). The exergy loss was mainly concentrated in the drying chamber, that is, the drying process, and the newly connected condenser and reheater had good exergy efficiencies, exceeding 60%.

Design of a low-cost IoT-based data logger for monitoring the palm sugar drying system using ESP32 and Modbus/MQTT conversion

Design of a low-cost IoT-based data logger for monitoring the palm sugar drying system using ESP32 and Modbus/MQTT conversion

Review Paper on Diffierent Types of Solar Dryer

Abstract: One of the most appealing and economical uses of solar energy is drying agricultural goods. With differing degrees of technical performance, a multitude of solar dryer types have been devised and developed across the globe. In general, solar dryers come in four different varieties: (1) direct solar dryers, (2) indirect solar dryers, (3) mixed-mode dryers, and (4) hybrid solar dryers. The product being dried, as well as technical and financial concerns, are reviewed in this paper together with other solar dryer kinds. Technically speaking, integrated storage, high efficiency, compact collector design, and long-life drying systems are the main focuses in the development of solar-assisted drying systems for vegetables. There exist alternative systems to air-based solar collectors. By using a water-to-air heat exchanger, water-based collectors are another option. A water-to-air heat exchanger can be used to push hot air used for drying agricultural products to pass through it. As part of the solar drying system, the hot water tank stores heat

Dehydration of Onion Slices for Food Processing Application Using Internet of Things-Based Smart Solar Drying System

Abstract Indian onion producers experience significant economic losses as a result of the unpredictable fluctuations in onion prices during the harvesting and postharvest stages. To address these difficulties and increase farmers' earnings, the transformation of onions into value-added goods such as onion paste, onion powder, onion sauce, and onion oil has emerged as a possible option. The objective of this project is to create a smart solar drying system based on Internet of Things (IoT) technique specifically designed for the dehydration of recently harvested red onions. In April 2023, a series of five experimental tests were carried out, examining the effects of different onion slice thicknesses ranging from 2 mm to 4 mm, with intervals of 0.5 mm. Each trial consisted of running the dryer for a duration of 9 h, specifically from 9:00 a.m. to 6:00 p.m., throughout the daylight hours for three consecutive days. The experiment involved evaluating different drying characteristics, such as moisture content on dry and wet bases, shrinkage ratio, and thermal efficiency. The drying time required to achieve a 10% moisture level (w.b.) was reduced by 30.19%, 16.98%, 11.32%, and 3.77% when comparing a 4-mm slice thickness to thinner alternatives of 2 mm, 2.5 mm, 3 mm, and 3.5 mm, respectively. The dryer had a superior thermal efficiency of 27.89% when the thickness was 2 mm, in contrast to 19.50% when the thickness was 4 mm. Significantly, onions that were dehydrated from slices measuring 2 mm and 2.5 mm in thickness showed exceptional suitability for the production of powdered onion.

Cooling the high temperature nutrition solution to improve growth, yield and water productivity of hydroponic red lettuce (Lactuca sativa L Var Red rapids) in a tropical location

Red lettuce is preferred because of its high nutritional, vitamin, and antioxidant contents. Hydroponic cultivation has been known to successfully improve the quality and productivity of red lettuce. But the efforts to increase the productivity of hydroponic red lettuce face constraints of high temperatures in the tropics. The aim of this study was to compare the growth, yield, and water productivity of red lettuce in three hydroponic systems namely wick, floating raft, and dry systems by controlling the temperature of the nutrient solutions using protected nutrient containers. The experimental design of randomized complete block split plots with the main plots of the nutrient containers which consisted of three levels: Refrigerated container, styrofoam-insulated container, and bare bucket container in which the nutrient solution was delivered to plants in three separated gutters as the cultivation beds, then recirculated back to the corresponding nutrient container. The secondary plot is hydroponic systems including three systems namely wick, floating raft, and dry systems. The blocks were the arrangement of plants according to the flow direction of the nutrient solution, namely upstream, middle and downstream in each gutter. Each experimental unit was represented by 3 plants. Data sets were analyzed by using analysis of variance and followed by LSD multiple comparisons at the 5% level. The results showed that the temperature of the nutrient solution controlled by the three containers had a significant effect on all observed plant parameters. Meanwhile, the hydroponic systems and the blocks had no significant effect. The use of Refrigerated container showed the best performance in improving the growth, yield, and water productivity of the red lettuce.

Robustness assessment of an automated AI-based white blood cell morphometric analysis system using different smear preparation methods.

Numerous AI-based systems are being developed to evaluate peripheral blood (PB) smears, but the feasibility of these systems on different smear preparation methods has not been fully understood. In this study, we assessed the impact of different smear preparation methods on the robustness of the deep learning system (DLS). We collected 193 PB samples from patients, preparing a pair of smears for each sample using two systems: (1) SP50 smears, prepared by the DLS recommended fully automated slide preparation with double fan drying and staining (May-Grunwald Giemsa, M-G) system using SP50 (Sysmex) and (2) SP1000i smears, prepared by automated smear preparation with single fan drying by SP1000i (Sysmex) and manually stained with M-G. Digital images of PB cells were captured using DI-60 (Sysmex), and the DLS performed cell classification. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were used to evaluate the performance of the DLS. The specificity and NPV for all cell types were 97.4%-100% in both smear sets. The average sensitivity and PPV were 88.9% and 90.1% on SP50 smears, and 87.0% and 83.2% on SP1000i smears, respectively. The lower performance on SP1000i smears was attributed to the intra-lineage misclassification of neutrophil precursors and inter-lineage misclassification of lymphocytes. The DLS demonstrated consistent performance in specificity and NPV for smears prepared by a system different from the recommended method. Our results suggest that applying an automated smear preparation system optimized for the DLS system may be important.

Lifetime thermal analysis of the CANDU spent fuel storage canister at the Wolsung site

CANDU spent fuels in the Wolsung site have been stored in dry storage systems, such as concrete canisters and modular air-cooled storage system. The primary role of the canister is to ensure the integrity of the fuel during the storage period, which is significantly influenced by temperature. Thus, thermal analysis for the canister's components, especially for fuel cladding, is essential to demonstrate its safety. The thermal analysis has been conducted mainly for predicting the peak cladding temperature (PCT) since high temperature of the fuel can promote oxidation and cracking. As the expiration of storage license approaches, fuel transfer to final disposal should be prepared. This also requires a thermal analysis to predict minimum cladding temperature (MCT), which is related with brittleness. So, it is crucial to accurately predict both PCT and MCT during entire storage period. The cladding temperature is primarily influenced by decay heat and ambient conditions. The lifetime PCT may occur during summer at the beginning of storage, while the lifetime MCT occurs during winter at the end of storage. In this study, we calculated the PCT and MCT during the entire storage period using a realistic thermal analysis model and, subsequently, conducted their uncertainty analysis.

Progress and Challenges of Vanadium Oxide Cathodes for Rechargeable Magnesium Batteries.

Among the challenges related to rechargeable magnesium batteries (RMBs) still not resolved are positive electrode materials with sufficient charge storage and rate capability as well as stability and raw material resources. Out of the materials proposed and studied so far, vanadium oxides stand out for these requirements, but significant further improvements are expected and required. They will be based on new materials and an improved understanding of their mode of operation. This report provides a critical review focused on this material, which is embedded in a brief overview on the general subject. It starts with the main strategic ways to design layered vanadium oxides cathodes for RMBs. Taking these examples in more detail, the typical issues and challenges often missed in broader overviews and reviews are discussed. In particular, issues related to the electrochemistry of intercalation processes in layered vanadium oxides; advantageous strategies for the development of vanadium oxide composite cathodes; their mechanism in aqueous, "wet", and dry non-aqueous aprotic systems; and the possibility of co-intercalation processes involving protons and magnesium ions are considered. The perspectives for future development of vanadium oxide-based cathode materials are finally discussed and summarized.

Drying behavior and nutritional quality of bitter‐gourd slices dried in a solar dryer with tray and skewer arrangement

AbstractIn this investigation, we assessed the efficacy of an indirect‐type solar drying system that utilized skewers and rack arrangements, comparing it to a conventional drying cabinet equipped with trays for dehydrating bitter gourd slices. We examined the influence of pretreatment methods and loading quantities on the solar drying process for bitter gourd slices in both configurations. The drying behavior of various combinations was scrutinized, and the physicochemical attributes of the dried bitter gourd samples, including total phenolic content, total flavonoid content, total chlorophyll content, antioxidant capacity, ascorbic acid content, and color, were analyzed. Rehydration characteristics, such as rehydration ratio, coefficient of rehydration, percent water in the rehydrated sample, and hardness of the rehydrated sample, were also determined. The bitter gourd slices achieved a final moisture content of 6.84%–8.27% wb after drying from an initial range of 88%–90% wb, within a total elapsed time of 28–55 h. The solar drying cabinet utilizing skewers exhibited enhanced efficiency, featuring reduced drying time and superior product quality compared to the tray‐equipped drying cabinet. This improved performance is ascribed to enhanced hot air circulation over the produce surface, facilitated by the uniform spacing between skewers on racks within the drying chamber.

Determination of optimal air supply form on sludge convective drying process: A CFD-DEM study

Convective thermal drying is usually used in sludge dryers, and the air supply forms significantly affect the sludge drying efficiency. In this work, the drying process of multi-layered sludge is numerically simulated using a coupled computational fluid dynamics-discrete element method (CFD-DEM) approach. Better than our previous work, the current CFD-DEM model further considers the dynamic process of humidity within the flow field. Firstly, the CFD-DEM model is validated based on the mechanistic experimental data. Then, extensive numerical simulations are carried out to investigate the two-layered sludge drying process in the dryer, and the effects of two conventional air supply forms (Top-to-Bottom and Bottom-to-Top) as well as a novel air supply form (Side-assist) on the two-phase flow system are discussed. The simulation results provide in detail the dynamic processes of momentum, heat and mass (moisture) in the convective drying system under different working conditions. Following recommendations are presented to facilitate the operation of the dryer: Bottom-to-Top is better for sludge drying and tends to utilize less heat from the heat source compared to the Top-to-Bottom. The drying efficiency can be further improved by supplying the Side-assist with an optimal flow ratio of side-wind to bottom-wind. Numerical results show that the optimal flow ratio is related to the total air volume, the deflection angle and the side-wind temperature. The present study reveals in depth the impact mechanism of the air supply form on the convective thermal drying process of sludge, which contributes to the design and optimization of high-efficiency dryers.

Numerical simulation of continuous microwave drying of rice grains

AbstractTo comprehensively understand temperature and moisture changes in a continuous microwave rice grain drying system, this study proposes a simulation strategy that facilitates the continuous movement of rice grains. The study establishes a three‐dimensional model concerning multiple physical fields, including electromagnetism, heat, and mass transfer. It examines the effects of rice grain layer thickness and microwave intensity on the moisture and temperature of rice grains. The results indicate that the drying rate is negatively correlated with material thickness but positively correlated with temperature. The optimal thickness for the rice grain layer is 8 mm. Furthermore, both the microwave drying rate and temperature increase with microwave intensity. These findings contribute to a deeper understanding of the hydrothermal change mechanisms in rice grains during microwave drying.Practical applicationsMicrowave drying, as an emergent drying technology, has garnered widespread attention for its selective heating, efficient drying, energy savings, and environmental protection. Nevertheless, enhancing uniformity during the microwave heating process constitutes an important research topic in scientific research and technological applications. Numerical simulation methods can visually analyze electric field distribution, thereby optimizing microwave heating uniformity and improving drying effects. This article aims to accurately predict the continuous microwave drying time of paddy and maximize energy usage by optimizing drying thickness and microwave power parameters establishing a mathematical model for the process. The study not only provides a solid theoretical basis for microwave dryer design but also scientifically guides the continuous microwave drying of rice and other food crops.

Experimental and numerical investigation of the incorporation of an air temperature controller for indirect solar dryers

Solar drying systems often face the challenge of overheating due to uncontrolled solar collectors, which can degrade the quality of dried products by destroying enzymes, vitamins, and their chemical composition. To address this issue, we developed and validated a new control system for stabilizing drying air temperature using both experimental and CFD numerical methods. This system not only effectively maintains the desired air temperature but also extends the lifespan of solar collectors by adjusting their exposure during periods of excessive solar radiation. The experimental results demonstrated that without the control system, the air temperature peaked at 72 °C, leading to potential product degradation. In contrast, the control system has succeeded in stabilizing the air temperature at an optimum level. Additionally, the validated CFD model confirmed the effectiveness of this control technique in various climatic conditions, including cold semi-arid, typically Mediterranean, hot semi-arid, and sub-desert conditions. The findings underline the importance and necessity of temperature control in solar drying systems, as well as the effectiveness of the CFD method in predicting system performance. Furthermore, this work significantly enhances the efficiency and applicability of solar drying technology, offering a practical solution for improving product quality and system durability.

Evaluation of integrated threshing and drying design concepts for paddy rice using analytical hierarchy process

Threshing and drying are two major postharvest activities that contribute significantly to postharvest losses for small and medium-scale rice farmers, leading to food insecurity and hunger in Sub-Saharan Africa. Developing an appropriate system for threshing and drying needs urgent attention. The objective of the study involved the use of Analytical Hierarchy Process (AHP) for evaluation and selection of the best option among four design concepts for development and fabrication. The four design concepts shortlisted were: (1) batch flow biomass-powered manual threshing and drying system, (2) recirculating diesel-powered mobile threshing and drying system, (3) mechanized threshing with solar drying batch system, and (4) tractor-powered recirculating continues flow integrated system. For the MCAHP analysis, 17 attributes were proposed and divided into five main criteria. The evaluation of the main criteria showed that cost had the highest score, followed by performance, safety, ease of installation and operation, and manufacturability, with a global score of 0.560, 0.202, 0.108, 0.083 and 0.048, respectively. It was observed that design concept two received the highest weighted score of 0.35 and was selected as the design concept to proceed with. The consistency ratios of the main criteria and attributes were all less than 0.1, which is the allowable limit of inconsistency. In conclusion, concept 2 was selected as the best design for developing an integrated threshing and drying system for paddy rice and is recommended for development, fabrication, evaluation and optimisation. Int. J. Agril. Res. Innov. Tech. 14(1): 30-44, June 2024

Modelling and Simulation of Chemical Adsorption Heat Pump for Drying and Heating Applications

The performance of a chemical adsorption heat pump drying system is largely influenced by the selection of working fluid, operating conditions, and system configuration and design. In this study, tomato slices were dried at five different air temperatures (35 °C, 40 °C, 45 °C, 50 °C, and 55 °C) with a tomato slice flow rate of 400 kg/hr and an air flow rate of 200 kg/hr using a modelled and simulated chemical adsorption heat pump drying system. Four adsorbent-adsorbate pairs were used: magnesium chloride-methanol, calcium chloride-ethanol, calcium chloride-water, and aluminium trifluoride-dimethyl ether, at evaporating and condensing temperatures of 10 °C and 15 °C, respectively. The specific moisture extraction rate ranged from 0.116 kg/kWh to 0.149 kg/kWh. The coefficient of performance (COP) of the heat pump drying (HPD) system ranged from 0.960 to 0.987, and the overall exergy efficiency at the highest ambient air temperature (30 °C) ranged from 3.84% to 20.29%. Exergy analysis of the system's components revealed that the condenser and evaporator contributed significantly to exergy destruction, exhibiting low exergy efficiency.

Evaluation of the Performance of Modeled and Simulated Hybrid Heat Pump Drying Systems for Industrial Applications

System configuration and design is one of the major factors that influence the performance of heat pump drying system. This study aimed to evaluate the performance and drying efficiency of two different configuration of hybrid heat pump drying system for heating process and drying of tomatoes slices at condensing temperature 15 ℃ and evaporating temperature 10 ℃ using calcium chloride-ethanol as adsorbate-adsorbent pair. The energetic coefficient of performance, and exergetic coefficient of performance and overall exergy efficiency of the system are 2.03, 15.6% and 17% respectively for simple adsorption-compression hybrid heat pump drying system while its specific moisture extraction rate is 0.234 kg/kWhr and specific energy consumption is 4.27 kg/kWhr. The energetic coefficient of performance, and exergetic coefficient of performance and overall exergy efficiency of the system are 2.18, 22.6% and 16% respectively for cascaded adsorption-compression hybrid heat pump drying system and its specific moisture extraction rate is 0.457 kg/kWhr and specific energy consumption is 3.17 kg/kWhr.

Reliability Evaluation for Mercury Stable Isotope Ratio Measurement by MC-ICP/MS

This study assessed the reliability of Mercury (Hg) stable isotope ratio measurements using MC-ICP/MS hyphenated with three different systems: wet plasma, dry plasma, and a cold vapor generator (CVG). Precision measurements using wet plasma improved with concentration, showing a range of 0.4 - 10.0% at 100 µg/L, with corresponding accuracy from 0.0 – 0.4%. By contrast, dry plasma demonstrated precision between 0.02 - 2.2% at 10 µg/L for 202/198Hg, with accuracy ranging from 1.2 - 1.4%. The CVG system, however, displayed significantly enhanced accuracy, from 0.2% for 199/198Hg to 0.9% for 204/198Hg at 0.1 µg/L. The study also incorporated a mass bias correction using a thallium (NIST 997 standard) internal spike, emphasizing the importance of maintaining a total Hg beam above 0.5 V to ensure measurement precision and accuracy. The findings suggest that the CVG method is most suitable for environmental samples with trace Hg concentrations, while both dry and wet plasma systems can serve effectively at higher concentrations (≥ 100 µg/L), given their analytical convenience and performance.