Air Pump Research Articles

Design and experimental assessment of a field-spraying system with nozzles employing reciprocating up-and-down movements.

Proper dense planting pattern can improve rice yield. For an ordinary boom sprayer, it is still difficult for the droplets to penetrate the dense rice canopy even if an auxiliary airflow is used, especially in the middle and late growth stages. The deposits of droplets at the bottom of the rice plants are typically small. In this study, a spraying system was designed with nozzles creating reciprocating movements into the middle and bottom of the rice canopy. An air pump provided power to push the nozzles up and down. A time relay and a solenoid valve were used to control the cycle and stroke of the reciprocating movement. At different growth stages of rice, comparative tests were conducted between the air-assisted spraying pattern (without reciprocating movement of nozzles) and the reciprocating movement spraying pattern (without auxiliary airflow). The results showed that for the reciprocating movement spraying pattern, the droplet number densities in the middle and bottom of the rice in the late growth stages increased from 78 to 124/cm2 and from 19 to 121/cm2 , respectively, and the coverage rates increased from 13.34% to 24.26% and from 3.61% to 21.21%, respectively. The droplet depositions increased from 0.603 to 1.139 mg cm-2 and from 0.095 to 1.001 mg cm-2 , respectively. This spraying pattern can increase droplet deposits at the middle and bottom of the crop and improve uniformity. © 2023 Society of Chemical Industry.

An ejector-assisted integrated thermal management of electric vehicles switchable between heating and cooling (reversible AC/HP)

Electric vehicles have become increasingly widespread in recent years due to environmental issues and limited natural resources, and the related thermal management strategies are receiving growing notice. A heat pump air conditioning system for cabin and battery pack thermal regulation (both heating and cooling) is proposed and studied under different operating conditions. The attention of the present study is more directed towards the heating mode of operation; cabin air conditioning in winter and electric aircraft application. Due to environmental considerations and restrictive laws, environmentally friendly refrigerants are also considered as alternatives for R134a. To improve the system's performance, an ejector is placed before the compressor and the refrigerant temperatures in the evaporator and chiller are set to be different. The performance of the proposed system is studied for both heating and cooling modes to compare with the basic system (without ejector). An exergy analysis is also carried out to further analyze the thermodynamic characteristics of the system. The results indicate that the proposed system's COP is improved for both cooling and heating modes under all operating conditions. For the heating mode, the highest COP was equal to 4.36 for R600a, and the COP improvement was between 8 and 47 % based on the different operating conditions. For the cooling mode, the highest COPs were equal to 5.20 and 5.17 for R600a and R1234ze(E) atTevap=Tchil=5°C respectively. The COP improvement for R600a was equal to 14 % atTevap=Tchil=−25°C, and it increases as the chiller temperature is raised. The exergy analysis also indicate that the highest exergy destruction occurs in the compressor and throttling valves. Moreover, R600a and R1234ze(E) show a better overall performance compared to other refrigerants. R600a and R1234ze(E) resulted in the least total exergy destruction of approximately 41 kW for the cooling mode and 51 kW for the heating mode. The exergy efficiency for R600a and R1234ze(E) was equal to 64 and 63 % respectively for both the cooling and heating modes.

Automatic Demand Fish Feeder

Humans have kept fish for thousands of years for commercial, research, and aesthetic purposes. These fishes are kept in aquariums, ponds, and other containments and require regular feeding and care. Traditional feeding techniques involve manually dispensing the food at regular intervals, they must alsobe able to control all kinds of factors such as feeding, air pumps, light, and the pH value of water, which may affect the fish. Overall, it’s a labor-intensive process. This research aims to develop a simple prototype automatic fish feeder. The product is designed to simplify the process of feeding fish in aquariums or fish farms. The feeder is equipped with obstacle avoidance technology, allowing it to move around the aquarium and ensure equal feeding for all fish. Additionally, the feeder includes a pH sensor, constantly monitoring the water quality in the aquarium to ensure a healthy environment for the fish. This technology not only simplifies the feeding process but also helps to maintain the well-being of aquatic life

Distributed multi-heat-source hybrid heating system based on waste heat recovery for electric vehicles

Air-conditioners usually consume the most electricity among all of the auxiliary components in an electric bus, over 30% of the battery power at maximum. A distributed multi-heat-source phased control method was developed to reduce the energy consumption of heating in electric vehicles (EVs). This method combines the application of multiple heat sources, including waste heat from battery cooling, motor and controller cooling, and positive temperature coefficient heating. Analyzed the internal thermal process and heat generation law of the power battery, and explored the thermal process of the driving motor and its controller. Apply the cooling waste heat from the power battery and the driving motor to the heating system of pure electric vehicles. The heat sources are distributed at different locations on the vehicle and provide heating in stages at various temperatures. Numerical analysis was conducted to calculate the heat output of each heat source, and a phased control strategy for the air conditioning system was designed according to the heat release characteristics and magnitudes of each component. Heating control functions for different stages were established at varying temperatures. The temperature rise patterns at different points on the vehicle were examined, and the positions of the heat sources were redesigned accordingly. The proposed method selects the appropriate heating mode according to factors such as the external temperature, the heat release sequence of the heating components, and passenger comfort requirements. Low-temperature experiments were performed at different temperature stages to compare the heating performance of this method with those of traditional heating methods and heat pump air conditioning for new energy vehicles. The experimental results show that the heating system has good heating effect. Compared with heat pump air conditioning and PTC heating, the proposed collaborative system saved 31.1% and 63.6% of energy, respectively, after operating at − 22℃ for 2 h. It demonstrates good energy-saving and heating performances at different temperature stages. The heating method is currently one of the best energy-saving solutions for EVs.

Computational and experimental investigations of a microfluidic mixer for efficient iodine extraction using carbon tetrachloride enhanced with gas bubbles

Numerous studies have been conducted on microfluidic mixers in various microanalysis systems, which elucidated the manipulation and control of small fluid volumes within microfluidic chips. These studies have demonstrated the ability to control fluids and samples precisely at the microscale. Microfluidic mixers provide high sensitivity for biochemical analysis due to their small volumes and high surface-to-volume ratios. A promising approach in drug delivery is the rapid microfluidic mixer-based extraction of elemental iodine at the micro level, demonstrating the versatility and the potential to enhance diagnostic imaging and accuracy in targeted drug delivery. Micro-mixing inside microfluidic chips plays a key role in biochemical analysis. The experimental study describes a microfluidic mixer for extraction of elemental iodine using carbon tetrachloride with a gas bubble mixing process. Gas bubbles are generated inside the microcavity to create turbulence and micro-vortices resulting in uniform mixing of samples. The bubble mixing of biochemical samples is analyzed at various pressure levels to validate the simulated results in computational fluid dynamics (CFD). The experimental setup includes a high-resolution camera and an air pump to observe the mixing process and volume at different pressure levels with time. The bubble formation is controlled by adjusting the inert gas flow inside the microfluidic chip. Microfluidic chip-based gas bubble mixing effects have been elaborated at various supplied pressures.

A novel sinusoidal design for an electrocoagulation reactor followed by an electro-Fenton reaction and a porous ceramic filter for the treatment of polluted waters.

In this research work, a novel design of an electro-Fenton reactor for the treatment of polluted water was investigated. In addition to the reactor with iron electrodes, a ceramic filter was also used. An electrical circuit was designed to change the cathodes and anodes every 24 s via an electrical relay between the electrodes. The untreated water was sucked into the reactor with an air pump and entered the electrocoagulation chamber after filtration with a ceramic filter. Then, it flows to the polyethylene filter to separate the coagulated particles from the fresh water. To produce 12 L of clean water, the system consumed 100 W of energy. Analysis of a river sample showed a reduction in nephelometric turbidity units (NTUs), total suspended solids (TSS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD). Turbidity reduction studies have shown that the system can improve water transparency by 95%, thereby improving water quality to acceptable levels. Further, this system reduced TSS by more than 86%. In addition, BOD was reduced by more than 84% and COD by more than 88%, as shown by the change in the ratio of BOD to COD from 0.44 to 0.625, indicating improved water quality. According to the results, the treatment system can clean polluted waters, particularly during floods and when industries discharge their effluents into rivers.

Observation of viscous liquid flow in tobacco substrate during heating using optical coherence tomography.

The present study used optical coherence tomography (OCT) to monitor the dynamics of a highly viscous liquid in a porous tobacco substrate during heating. The OCT technique was integrated with a specially designed heating chamber and an air pump for measuring. Two transitional points in the liquid behaviours at different temperatures were estimated using OCT and statistical analysis of the attenuation coefficient. The first point, 'A', shows the time approximation at which the penetration-dominant zone transitions into the evaporation-dominant zone. The second point, 'B', indicates the time approximation at which rapid evaporation of free liquid transitions into slow evaporation of trapped and bound liquid. This analytical system is an alternative for tracking liquid transport in porous biomass during heating.

CFD Simulation Based Ventilation and Dust Reduction Strategy for Large Scale Enclosed Spaces in Open Pit Coal Mines—A Case of Coal Shed

The coal shed is an enclosed space where raw coal is stored and handled. The intensive operation of the machinery inside the coal shed generates a large amount of dust, and the wind speed inside the enclosed space easily leads to a high concentration of dust, which endangers the physical and mental health of the workers. In this paper, we first studied the particle size distribution of dust samples in the coal shed and found that 12.2% of the dust in the air of the coal shed was 10–100 μm, 87.8% was less than 10 μm, and 72.9% was less than 2.5 μm. Fluent was used to simulate the law of dust dispersion in the coal shed under different working conditions, and finally, the simulation results were used to guide the design of the ventilation site and dust-reduction scenario. The experimental and simulation results show that under the same working conditions, the average dust reduction efficiency of the ventilation method in which the north side and south side pump air outside was 9.9%. The ventilation method in which the north side blows inside and the south side pumps outside was 23.7%. The average dust reduction efficiency of the ventilation method in which the north side blows inside and the south side pumps outside + placing the fan in the middle was 59.9%. The research results can provide some reference value for indoor air quality improvement.

Auxiliary Power Supply System with Parallel-Connected DC–AC Inverters for Low-Floor Light Rail Vehicle

This research proposes a roof-mounted auxiliary power supply (APS) system for 600 VDC low-floor light rail vehicles (LRVs). The proposed APS system consists of five parallel-connected dc–ac inverter modules (modules 1–5). Inverter modules 1 and 2 are three-phase dc–ac inverters for the compressor motors of the air conditioning system, and inverter modules 3 and 4 are three-phase dc–ac inverters for the air pump motors of the air supply system. Inverter module 5 is a single-phase dc–ac inverter for the 220 VAC power supply of onboard electric loads. Simulations and experiments were carried out under variable load torques and output frequencies for modules 1–4 and under full and no resistive loads for module 5. The measured total input current and total input power of the proposed APS system under the full-load condition are 114.36 A and 68.84 kW. The total efficiency of the proposed APS system (modules 1–5) is 97.05%. The proposed APS system is suitable for 600 VDC low-floor LRVs. The novelty of this research lies in the use of five parallel-connected inverter modules, as opposed to the three-phase output transformer or isolated dc–dc converter in the early and conventional APS systems. Specifically, the proposed APS system requires neither a three-phase output transformer nor an isolated dc–dc converter.

Microbial communities in aerosol generated from cyanobacterial bloom-affected freshwater bodies: an exploratory study in Nakdong River, South Korea.

Toxic blooms of cyanobacteria, which can produce cyanotoxins, are prevalent in freshwater, especially in South Korea. Exposure to cyanotoxins via ingestion, inhalation, and dermal contact may cause severe diseases. Particularly, toxic cyanobacteria and their cyanotoxins can be aerosolized by a bubble-bursting process associated with a wind-driven wave mechanism. A fundamental question remains regarding the aerosolization of toxic cyanobacteria and cyanotoxins emitted from freshwater bodies during bloom seasons. To evaluate the potential health risk of the aerosolization of toxic cyanobacteria and cyanotoxins, the objectives of this study were as follows: 1) to quantify levels of microcystin in the water and air samples, and 2) to monitor microbial communities, including toxic cyanobacteria in the water and air samples. Water samples were collected from five sites in the Nakdong River, South Korea, from August to September 2022. Air samples were collected using an air pump with a mixed cellulose ester membrane filter. Concentrations of total microcystins were measured using enzyme-linked immunosorbent assay. Shotgun metagenomic sequencing was used to investigate microbial communities, including toxic cyanobacteria. Mean concentrations of microcystins were 960 μg/L ranging from 0.73 to 5,337 μg/L in the water samples and 2.48 ng/m3 ranging from 0.1 to 6.8 ng/m3 in the air samples. In addition, in both the water and air samples, predominant bacteria were Microcystis (PCC7914), which has a microcystin-producing gene, and Cyanobium. Particularly, abundance of Microcystis (PCC7914) comprised more than 1.5% of all bacteria in the air samples. This study demonstrates microbial communities with genes related with microcystin synthesis, antibiotic resistance gene, and virulence factors in aerosols generated from cyanobacterial bloom-affected freshwater body. In summary, aerosolization of toxic cyanobacteria and cyanotoxins is a critical concern as an emerging exposure route for potential risk to environmental and human health.

Combined Continued Air Pumping And Descemetotomy In Post- Phacoemulsification Descemet´s Membrane Detachment

Combined Continued Air Pumping And Descemetotomy In Post- Phacoemulsification Descemet´s Membrane Detachment

Small lateral air pressure gradients generated by a large chamber system have a strong effect onCO2transport in soil

AbstractGas transport in soils is usually assumed to be purely diffusive, although several studies have shown that non‐diffusive processes can significantly enhance soil gas transport. These processes include barometric air pressure changes, wind‐induced pressure pumping and static air pressure fields generated by wind interacting with obstacles. The associated pressure gradients in the soil can cause advective gas fluxes that are much larger than diffusive fluxes. However, the contributions of the respective transport processes are difficult to separate. We developed a large chamber system to simulate pressure fields and investigate their influence on soil gas transport. The chamber consists of four subspaces in which pressure is regulated by fans that blow air in or out of the chamber. With this setup, we conducted experiments with oscillating and static pressure fields. CO2concentrations were measured along two soil profiles beneath the chamber. We found a significant relationship between static lateral pressure gradients and the change in the CO2profiles (R2 = 0.53;p‐value <2e‐16). Even small pressure gradients between −1 and 1 Pa relative to ambient pressure resulted in an increase or decrease in CO2concentrations of 8% on average in the upper soil, indicating advective flow of air in the pore space. Positive pressure gradients resulted in decreasing, negative pressure gradients in increasing CO2concentrations. The concentration changes were probably caused by an advective flow field in the soil beneath the chamber generated by the pressure gradients. No effect of oscillating pressure fields was observed in this study. The results indicate that static lateral pressure gradients have a substantial impact on soil gas transport and therefore are an important driver of gas exchange between soil and atmosphere. Lateral pressure gradients in a comparable range can be induced under windy conditions when wind interacts with terrain features. They can also be caused by chambers used for flux measurements at high wind speed or by fans used for head‐space mixing within the chambers, which yields biased flux estimates.

Is Ground Source Heat Pump the Future of Space Cooling in Southeast Asia?

The rapid economic growth of Southeast Asian countries is followed by accelerated population and energy demand growth. On the other hand, the region still relies heavily on fossil fuels as the primary source of electricity. As a result, there is a growing concern about future regional energy sustainability. Space cooling has become one of the fastest-growing energy sectors. Introducing a new space cooling technology capable of providing a higher thermal efficiency can be an alternative solution. The Ground Source Heat Pump (GSHP) is a proven technology to reduce the required energy for space cooling and heating in four-season countries. However, its performance in the tropical climate is still questionable. This paper describes the challenges of GSHP application in tropical climates, such as in Southeast Asia. The research conducted to investigate the suitability of GSHP system application in Southeast Asia is also discussed. While more data are being gathered from several GSHP pilot tests in Vietnam and Thailand, the short to medium-term performance data analysis shows its advantages over the conventional Air Source Heat Pump (ASHP) or standard air conditioner. However, extensive research is still required to evaluate its long-term performance and the financial advantages over the ASHP.

Organic loads reduction efficiency using natural fiber reinforced polymer encapsulated microalgae macrocapsule for wastewater treatment

Organic load such as Chemical Oxygen Demand (COD) increases in the water because of the increase in human growth and industrialisation. The initial goal of the study, to characterise the natural fibre reinforced polymer encapsulated microalgae macrocapsule using Scanning electron microscope (SEM). Second, analyse organic load reduction utilising natural fiber reinforced polymer encapsulated microalgae macrocapsule. The experiment was conducted with five Schott bottles with a 1.7 liter working volume as a photobioreactors. The system was operated with three tubes fabricated with different functions. The first tube was connected to the adjustable air pump oxygen aerator to supply oxygen into the photobioreactor system. The photobioreactor’s second tube is designed to flow out gasses. The last tube is the sampling tube function to withdraw the samples for the efficacy of treatment performance. The photobioreactor will continuously be illuminated with cool-white fluorescent light (Philip TL-D 36W/865, light intensity of 60–70 μmol m-2 s-1). This study employs COD to test microalgae’s organic load reduction. From day 1 to 5, COD value shows a pattern of reduction from 352 mg/L for day 1 and 223 mg/L for day 5, respectively. The analysis reveals that the p-OPEFB (Polymeric Oil Palm Empty Fruit Bunch) macrocapsule has a surface structure with a rough surface before and after treatment. Optical density measures microalgae growth. BBM’s (Bold Basal Medium) increasing absorbance value allows microalgae to develop optimally. Natural fibre reinforced polymer encapsulated microalgae macrocapsule shows potential for wastewater treatment.

ANCIENT KEDAH IRON SMELTING EXPERIMENT IN PREPARATION FOR OFFERING ARCHAEOLOGICAL TOURISM HERITAGE PACKAGES AT SUNGAI BATU ARCHAEOLOGICAL COMPLEX (SBAC), BUJANG VALLEY, KEDAH, MALAYSIA

In order to obtain primary data related to the iron smelting activities, the experimental process of furnaces, tuyere and air pumps making is carried out. The experiment has conducted since 2013 through the Knowledge Transfer Program (KTP) in Sungai Batu Archaeological Complex (SBAC). Through the experiment, the clay in this complex has been used as a raw material for furnaces and tuyere making while the bellows is made of wood, plywood and fabric. In order to complete the experiment regarding the raw material that use for iron smelting, iron ore was taken through survey activities in the area of Kampung Batu 5, UiTM Merbok and Bukit Tupah while charcoal was used from rubber wood in the rubber plantation near the Sungai Batu Archaeological Complex. After the experiment was conducted, the results recorded were different from the findings of the iron ingot excavation at the iron smelting site which is likely to occur due to the difference in technique and ratio of materials used during smelting activities. Although the results obtained during the experiment are different, the smelting process can be used as the main reference for offering tourism full packages related to the demonstration of iron smelting in this complex to foreign tourists.

Thermo-dynamic and economic analysis of a novel pumped hydro-compressed air energy storage system combined with compressed air energy storage system as a spray system

The efficiency of adiabatic compressed air energy storage technology is limited by the low utilization of thermal energy in the energy storage room. Therefore, a pumped hydro-compressed air energy storage system combined with a compressed air energy storage system as a spray system is introduced in the present research and analyzed by thermodynamic and economic analysis to verify the feasibility of system. For the performance analysis of the system, the main components and the whole system are precisely analyzed from the thermodynamic point. The results show that the round-trip efficiency and total exergy efficiency of the system are 52.45% and 77.8%. The system can significantly improve the air temperature in the air storage room, reduce the pressure energy loss of the system, and increase the energy storage capacity. Moreover, achieving high system round-trip efficiency is dependent on components of the system with high efficiencies. By optimization of the system operation mode, the round-trip efficiency of the system can reach 56%.

Effects of air blower and pump failures on the performance of A2O processes for wastewater treatment

The unexpected failure of equipment such as pumps and fans in wastewater treatment plants can reduce wastewater treatment efficiency, leading to direct leakage of untreated wastewater into the environment. It is hence important to predict the possible consequences of equipment failure to minimize the leakage of harmful substances. This study examines the impacts of equipment shutdown on the performance and recovery time of a laboratory-scale anaerobic/anoxic/aerobic system with regard to reactor conditions and water quality. Two days after the air blowers are stopped, the concentrations of the soluble chemical oxygen demand, NH4–N, and PO4–P in the effluent of the settling tank increase to 122 mg/L, 23.8 mg/L, and 46.6 mg/L, respectively. These concentrations return to their initial values after 12, 24, and 48 h of restarting the air blowers. The concentrations of PO4–P and NO3–N in the effluent increase to 58 mg/L and 20 mg/L, respectively, about 24 h after stopping the return activated sludge and mixed liquor recirculation pumps, owing to the release of phosphates in the settling tank and inhibition of denitrification.

A comparison of passive and active dust sampling methods for measuring airborne methicillin-resistant Staphylococcus aureus in pig farms.

Methicillin-resistant strains of Staphylococcus aureus (MRSA) are resistant to most β-lactam antibiotics. Pigs are an important reservoir of livestock-associated MRSA (LA-MRSA), which is genetically distinct from both hospital and community-acquired MRSA. Occupational exposure to pigs on farms can lead to LA-MRSA carriage by workers. There is a growing body of research on MRSA found in the farm environment, the airborne route of transmission, and its implication on human health. This study aims to directly compare two sampling methods used to measure airborne MRSA in the farm environment; passive dust sampling with electrostatic dust fall collectors (EDCs), and active inhalable dust sampling using stationary air pumps with Gesamtstaubprobenahme (GSP) sampling heads containing Teflon filters. Paired dust samples using EDCs and GSP samplers, totaling 87 samples, were taken from 7 Dutch pig farms, in multiple compartments housing pigs of varying ages. Total nucleic acids of both types of dust samples were extracted and targets indicating MRSA (femA, nuc, mecA) and total bacterial count (16S rRNA) were quantified using quantitative real-time PCRs. MRSA could be measured from all GSP samples and in 94% of the EDCs, additionally MRSA was present on every farm sampled. There was a strong positive relationship between the paired MRSA levels found in EDCs and those measured on filters (Normalized by 16S rRNA; Pearson's correlation coefficient r = 0.94, Not Normalized; Pearson's correlation coefficient r = 0.84). This study suggests that EDCs can be used as an affordable and easily standardized method for quantifying airborne MRSA levels in the pig farm setting.

Analysis of the Influence of EXV on Heat pump air conditioning system based on AMESim

Analysis of the Influence of EXV on Heat pump air conditioning system based on AMESim

100 Lightweight Air Sampling Badge for Material-Specific Monitoring of Workplace Aerosol Exposure

Abstract Monitoring occupational exposure to hazardous airborne materials like carbon nanotubes (CNTs) or graphene is an inevitable element of every risk mitigation strategy to protect employees. Conventional air samplers are often bulky, need to be operated by trained personnel and results are not available on-site. Here, we address these issues and introduce the patented Stat Peel Identifier system comprised of portable, lightweight sampling badges and a fully automatized Raman spectroscopy-based bench-top reader. This presentation is focused on the characterization of our air sampling badge and its capabilities in combination with our reader. The badges feature silent micro air pumps and a series of sensors to monitor flow rate, temperature, relative humidity, TVOC and movement during sampling. Filtration slides provide the means for inertia-based particle separation and deposition onto collection membranes optimized for efficient particle retention and inspection with Raman spectroscopy. The sampling characteristic of the badges closely follows the respirable convention according to ISO 7708 with an average sampler bias below 10%. Our analytical approach to quantify the collected particles using Raman spectroscopy and in-house developed analysis routines provide unprecedented sensitivity and material-specificity enabling e.g., the unambiguous distinction between CNTs and carbon black. The Identifier system provides fast results directly on-site and facilitates continuous monitoring and recording of long-term exposure histories for locations and employees. Lastly, recent advancements in the development of our respirable sampler towards a combined respirable/thoracic sampler are discussed in the context of emerging fields of application ranging from RCS to active pharmaceutical ingredients and modern battery materials.