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The existing grape drying technology and equipment often have problems such as poor hygiene conditions, high drying costs, and large drug residues. Therefore, the market urgently needs grape drying equipment with low energy consumption, high efficiency, and a green-clean processing process. To solve the above problems, a piece of integrated drying equipment combining the two technologies of air impingement blanching and air impingement drying for multi-layer grape material drying is designed. The dried product quality is directly affected by the airflow field distribution. Therefore, obtaining good airflow distribution and airflow velocity uniformity in the drying chamber via parametric studies is essential to ensure uniform drying of products. Since parametric and optimization investigations by physical experiments are usually expensive and time-consuming, computational fluid dynamics (CFD) being a flexible and less expensive tool can be employed to perform such studies. In the current work, the airflow velocity distribution and uniformity of the drying material room are analyzed by Ansys Fluent software. The airflow velocity non-uniformity coefficient is used to evaluate airflow uniformity. Results show that the original design has poor uniformity and needs to be optimized. The influence of air inlet chamber deflection device and material truck airflow baffles on the flow field of the material drying room is investigated to improve the uniformity of airflow distribution. Considering drying efficiency and uniformity, drying material room structure with the addition of deflection device design with the structural parameters of L = 50 mm and θ = 76°, airflow baffle design with the structural parameters of h = 0 mm, θ 2 = 20° is chosen as the final optimized design. After optimization, the velocity of airflow between material layers has improved overall, and the maximum difference of average airflow velocity between material layers has been reduced from 0.73 m/s to 0.69 m/s, improving the drying uniformity of dried materials. In comparison to other drying equipment, the current integrated drying equipment combing air impingement blanching and drying has the advantages of being efficient and energy-saving, suitable for large-scale drying of grapes with better drying quality. The current results could guide the drying equipment design for grapes and develop the grape drying industry with high-dried quality.

Recently, flexible airflow sensors have attracted significant attention due to their impressive characteristics and capabilities for airflow sensing. However, the development of high‐performance flexible airflow sensors capable of sensing airflow over large areas remains a challenge. In this work, it is proposed that a hair‐like flexible airflow sensor, based on laser direct writing and electrostatic flocking, offers an efficient technology for airflow sensing. The airflow sensor exhibits high sensitivity (5.25% s m−1), fast response time (39.83 ms), a wide detection range (3.48 – 18.36 m s−1), minimal disturbance to the airflow field, simplified fabrication, and cost efficiency. The airflow sensor, with excellent conformal monitoring capabilities, is capable to detect airflow on different surfaces. The sensor's excellent flexibility and efficient fabrication process enable it to be easily integrated into arrays and deployed on large‐area surfaces to provide information, including airflow velocity, direction, and point of incidence. The hair‐like airflow sensor has significant potential for applications in environmental monitoring, intelligent robots, wearable electronics, and tactile sensing. A hair‐like flexible airflow sensor is designed for large‐area airflow sensing with carbon fibers implanted on a laser‐induced graphene substrate. The flexible airflow sensor features a wide detection range and fast response time, effectively identifying airflow changes. It is expected to demonstrate reliability in large‐area airflow sensing in numerous applications through its excellent performance.

Background: Clinicians and surgeons often require instant knowledge of the lung function of their patients during the course of their management though they rely on the symptoms most of the time. Yet unexpected, abnormal respiratory airflow patterns are found in various diseases which affect the management whereas many respiratory complaints used to turn out to be normal. Respiratory symptoms often but not always correlate with airflow abnormality, thus making office spirometry an important tool for addressing these problems. Aims and Objectives: An evaluation of the profile of airflow patterns observed among patients attending regional institute of medical sciences (RIMS) hospital, Manipur, is carried out. Materials and Methods: The spirometry test performances of total 221 patients (120 males and 101 females) aged between 11 and 80 years sent from outpatient and wards of different departments of our hospital (RIMS Imphal, Manipur) were done after taking informed consents. The period of test performance was from June 2016 to November 2018 on all working days in the department of physiology. For this, a computerized spirometer (Helios model no. 401) was used. Results: 176 (79.6% of the total studied) patients presented with symptoms of respiratory diseases and after spirometry test, 121 (54.7% of the total) were having different patterns of abnormal airflow. About 60% of 111 patients complaining only of breathlessness are found to have normal lung function. Among 13 patients with a common disease such as chronic obstructive pulmonary disease, unexpectedly 2 cases of restrictive type of airflow and another 2 patients with normal airflow were found. Conclusion: Awareness of such altered and unexpected occurrence in lung spirometry epidemiology would be informative to the physicians in disease management.

Multi-outlet air-assisted sprayers are increasingly used for directional and zoned airflow to match varying canopy structures. In this study, a self-developed multi-outlet orchard air-assisted sprayer was investigated. Airflow velocity and direction were tested at different inlet areas, heights, and downstream horizontal distances using a three-dimensional ultrasonic anemometer. Analysis of variance (ANOVA) and regression modeling were applied to elucidate the effects of these three factors on airflow velocity, horizontal angle (θ), and elevation angle (Φ). The results showed that a stable alternating “primary jet–interaction zone” structure was formed in the spatial airflow field under all operating conditions, indicating that the fundamental airflow pattern was mainly governed by the sprayer layout. Varying the inlet area did not alter the basic airflow structure; however, the intensity and directional stability of the primary jets were significantly modified. Larger inlet openings produced higher airflow velocities, with a maximum near-field velocity of 19.7 m s−1, whereas smaller inlet openings resulted in faster far-field attenuation and more pronounced diffusion. Increasing the inlet area caused the θ distribution peak to converge toward 0°, thereby improving axial coherence and directional stability. In contrast, decreasing the inlet area shifted Φ toward more negative values, with Φ reaching approximately −20° in the far field; moreover, far-field differences in Φ were more pronounced. Under the minimum inlet opening area condition (S1), the airflow velocity within the region 80–100 cm from the outlet can be stably maintained above 3 m/s, with a relatively uniform velocity distribution. This is beneficial for improving droplet deposition uniformity within the canopy and reducing droplet drift in non-target areas. Based on the experimental data, a regression model for mean airflow velocity was established (R2 = 0.873), demonstrating good predictive performance and indicating that inlet-opening regulation is feasible. These findings provide a basis for airflow matching and spray-parameter optimization for different canopy structures.

There is continuing debate about whether to define airflow obstruction by a post-bronchodilator ratio of forced expiratory volume in 1 second (FEV ) and forced vital capacity (FVC) below 0.70, or by ratio values falling below the age-dependent lower limit of normal (LLN) derived from general population data. To determine whether using the LLN criterion affects the classification and outcomes of patients previously defined as having chronic obstructive pulmonary disease by the fixed FEV /FVC ratio. We applied the LLN definition to pooled data from the Tiotropium Safety and Performance in Respimat study that used the fixed FEV /FVC ratio for the clinical diagnosis of chronic obstructive pulmonary disease. A total of 17,072 patients were analyzed; of these, 1,807 (10.6%) patients had a ratio greater than or equal to LLN. Patients with a ratio greater than or equal to LLN had similar risks of death from any cause and fatal major adverse cardiovascular (CV) event as those below LLN. Patients with a ratio below LLN had a significantly lower risk of major adverse CV events (hazard ratio = 0.69; 95% confidence interval [CI] = 0.55-0.86; P = 0.001), and had significantly greater risks of moderate to severe exacerbation (rate ratio = 1.48; 95% CI = 1.36-1.61; P < 0.0001) and severe exacerbation (rate ratio = 2.01; 95% CI = 1.68-2.40; P < 0.0001) when compared with patients greater than or equal to LLN. Study outcomes by treatment arm (5 μg tiotropium Respimat vs. 18 μg HandiHaler) were comparable. Using the LLN to define airflow obstruction would have excluded patients in the Tiotropium Safety and Performance in Respimat study with a higher risk of nonfatal major adverse CV events and a lower risk of exacerbation; study outcomes by treatment arm (2.5 μg/5 μg tiotropium Respimat vs. 18 μg HandiHaler) remained similar. Clinical trial registered with www.clinicaltrials.gov (NCT01126437).

To study the characteristics of nasal airflow in the presence of nasal cycle by computational fluid dynamics. CT scan data of a healthy Chinese individual was used to construct a three-dimensional model of the nasal cavity to be used as simulation domain. A sinusoidal airflow velocity is set at the nasal cavity entrance to reproduce the breathing pattern of a healthy human. There was a significant difference in the cross-sectional area between the two sides of the nasal cavity. Particularly, the decongested side is characterized by a larger cross-section area, and consequently, by a larger volume with respect to the congested side. The airflow velocity, pressure, and nasal resistance were higher on the congested narrow side. The temperature regulation ability on the congested narrow side was stronger than that on the decongested wider side. During the nasal cycle, there are differences in the nasal cavity function between the congested and decongested sides. Therefore, when evaluating the impact of various factors on nasal cavity function, the nasal cycle should be considered.

This article compares two methods for determining the air flow resistivity of porous and coating materials – a key parameter in sound absorption modelling. The analysis involves a modified static airflow measurement procedure in accordance with International Organization for Standardization (ISO) (2018), using a linear approximation algorithm (PLA), and a reverse method consisting of matching the measured absorption coefficient in an impedance tube to the Miki model. The analysis was conducted on both porous materials utilised in acoustic panel fillings and thin coverings. It is evident that both methods yield analogous outcomes for materials exhibiting low resistivity. However, for materials characterised by higher resistivity, discrepancies of up to 50% were observed. Nevertheless, a high degree of agreement was obtained between the calculated and measured absorption coefficients. For thin coating materials, an air gap of at least 70 mm is required. For materials with a thickness of up to approximately 30 mm, differences in resistivity do not significantly affect the absorption coefficient. It is evident that both methods can be used to determine the air flow resistivity of porous materials and layered structures, supporting the effective selection of materials according to requirements.

Controlling the ambient temperature inside a tunnel to less than 28 °C is the key to ensure safe operation of tunnels that experience high-geothermal temperature. One of the most popular methods to lower the ambient temperature of an extra-long tunnel with high-geothermal temperature is mechanical ventilation. Taking the Layue tunnel as an example, this paper examined the impact of natural wind, piston airflow, and mechanical ventilation on tunnel thermal hazard control. The results show that the cooling effect of natural ventilation is better when natural wind flows from entrance to exit than when it blows from exit to entrance. When there is only natural ventilation, the length of tunnel ambient temperature higher than 28 ℃ is more than 15 km within 5.0 years of natural ventilation. Piston airflow does not significantly reduce the length of high tunnel ambient temperature distribution range. Only relying on natural wind and piston airflow cannot control heat damage in the Layue tunnel. The thermal layer can reduce the length over which high tunnel ambient temperature is distributed, but the maximum reduction is within 2500 m. When the mechanical airflow speed is at least 3.0 m s −1 , the heat damage can be effectively controlled within one year. Whether mechanical airflow is started in summer or winter, mechanical airflow shall be carried out at the speed of 3.0 m s −1 at least 200 days in advance to effectively control the heat damage of Layue tunnel.

This paper presents an airflow vector sensor for drones. Drones are expected to play a role in various industrial fields. However, the further improvement of flight stability is a significant issue. In particular, compact drones are more affected by wind during flight. Thus, it is desirable to detect air current directly by an airflow sensor and feedback to the control. In the case of a drone in flight, the sensor should detect wind velocity and direction, particularly in the horizontal direction, for a sudden crosswind. In addition, the sensor must also be small, light, and highly sensitive. Here, we propose a compact spherical airflow sensor for drones. Three highly sensitive microelectromechanical system (MEMS) differential pressure (DP) sensor chips were built in the spherical housing as the sensor elements. The 2D wind direction and velocity can be measured from these sensor elements. The fabricated airflow sensor was attached to a small toy drone. It was demonstrated that the sensor provided an output corresponding to the wind velocity and direction when horizontal wind was applied via a fan while the drone was flying. The experimental results demonstrate that the proposed sensor will be helpful for directly measuring the air current for a drone in flight.