High Air Humidity Research Articles

Vertical distribution of PbI2 nanosheets for robust air-processed perovskite solar cells

The fabrication of perovskite solar cells (PSCs) in ambient air is technologically favorable for commercialization, however, the photovoltaic performance of ambient-processed PSCs is still lagging behind their inert counterparts. One major challenge is the growth of high-quality perovskite films regardless of the ambient humidity. Here, we demonstrate an effective strategy to grow robust perovskite film with enlarged grain size, enhanced crystallinity, and preferred orientation in high-humidity air. More particularly, PbI2 2D nanosheets are formed and vertically distributed at the grain boundaries of perovskite films, playing a powerful passivation role. Upon our regulation of the crystallization of perovskite film and the distribution of PbI2, the according device shows significant improvement in efficiency and stability. As a result, we achieve a maximum power conversion efficiency (PCE) of 19.83% for MAPbI3-based device and over 21% for MA0.6FA0.4PbI3-based device. Moreover, these devices display remarkably improved operational stability in ambient air without encapsulation. This work provides a reliable and cost-effective strategy for the commercial manufacturing of PSCs.

Artificial Neural Network Assisted Multiobjective Optimization of Postharvest Blanching and Drying of Blueberries.

This study aimed to optimize the postharvest blanching and drying process of blueberries using high-humidity air impingement (HHAIB) and hot-air-assisted infrared (HAIR) heating. A novel pilot-scale hot-air-assisted carbon-fiber infrared (IR) blanching/drying system was developed. Fresh blueberries with an average diameter of 10~15 mm were first blanched with high-humidity air at 110 °C and 12 m/s velocity for different durations (30, 60, 90, and 120 s); subsequently, the preblanched blueberries were dried at different IR heating temperatures (50, 60, 70, 80, and 90 °C) and air velocities (0.01, 0.5, 1.5, and 2.5 m/s), following a factorial design. The drying time (DT), specific energy consumption (SEC), ascorbic acid content (VC), and rehydration capacity (RC) were determined as response variables. A three-layer feed-forward artificial neural network (ANN) model with a backpropagation algorithm was constructed to simulate the influence of blanching time, IR heating temperature, and air velocity on the four response variables by training on the experimental data. Objective functions for DT, SEC, VC, and RC that were developed by the ANN model were used for the simultaneous minimization of DT and SEC and maximization of VC and RC using a nondominated sorting genetic algorithm (NSGA II) to find the Pareto-optimal solutions. The optimal conditions were found to be 93 s of blanching, 89 °C IR heating, and a 1.2 m/s air velocity, which resulted in a drying time of 366.7 min, an SEC of 1.43 MJ/kg, a VC of 4.19 mg/100g, and an RC of 3.35. The predicted values from the ANN model agreed well with the experimental data under optimized conditions, with a low relative deviation value of 1.43-3.08%. The findings from this study provide guidance to improve the processing efficiency, product quality, and sustainability of blueberry postharvest processes. The ANN-assisted optimization approach developed in this study also sets a foundation for the smart control of processing systems of blueberries and similar commodities.

Simulation on the evaporative cooling characteristics of humid air-water outside staggered tube bundles

In this paper, a new model was established to investigate the evaporative cooling characteristics of humid air-water outside staggered tube bundles. The Euler Lagrange method was adopted based on the coupling between DPM (discrete phase models) and WFM (wall film models). The formation of spray water film by spray water droplets and the separation process of that are considered on the tube bundle walls in this model. The model reliability was verified by experimental data in literatures. Meanwhile, the process was simulated on the evaporative cooling of humid air-water outside staggered tube bundles. The results showed that the evaporation process of spray water outside staggered tube bundles is mainly concentrated near the wall and the wake area of humid air outside tube bundle. The evaporation rate of spray water is the lowest at the circle angle range of tube bundle which is − 45° – 45°, while it is the highest near the circle angle of ± 115°. To strengthen the convection between humid air and mainstream air in the area of tube bundle (circle angle is in the range of − 45° – 45°), the water vapor concentration should be reduced and the evaporation characteristics should be improved in this area. The evaporation rate of spray water can be negatively affected by relative humidity outside the staggered tube bundles. The secondary entry of high humidity air should be avoided from the exhaust port into the air inlet. The spray water flow has a positive effect on improving the evaporation rate of spray water. The above results provide guidance for the design of evaporative cooling characteristics of humid air-water outside staggered tube bundles.

Flexible conductive Ag-CNTs sponge with corrosion resistance for wet condition sensing and human motion detection

Three-dimensional (3D) polyurethane (PU) sponges featuring high mechanical elasticity, compressibility, and durability have emerged as an ideal substrate for building wearable strain sensors. However, the 3D porous structures easily soak up rain, water vapor, sweat, etc., and the constructed sensor’s long-term conductivity may be eroded by droplets and experience irreversible damage, rendering the preparation of a wearable flexible sponge sensor with environmental adaptation challenging. Here, by reducing the Ag particles in the carbon nanotube (CNT) suspension, forming a conductive filler Ag-CNTs, and combining with poly (vinylidene fluoride) (PVDF) solution, surface modification with polydimethylsiloxane (PDMS) solution, the PDMS/Ag-CNT-PVDF/PU sponge sensor with 3D conductive network and superhydrophobic structure was fabricated. The results revealed that this modified sponge had a wide strain detection range of 0–80 %, superior conductive sensitivity up to 4.24 kPa−1 in 0–20 kPa, and a fast and stable response time (170 ms) with great reproducibility over 1200 compression-resilience cycles. Furthermore, good superhydrophobicity endows the sensor with remarkable resistance to mechanical wear and chemical corrosion, which can be effectively used to detect human motion in high air humidity environment. This PDMS/Ag-CNTs-PVDF/PU sponge sensor is expected to be used as a practical, flexible wearable sensor and demonstrates potential application prospects in complex environments.

Species Inventory of Araceae In West Block of Batang Toru Forest, North Tapanuli Regency, North Sumatra

Araceae is a family plant that generally inhabits the tropical region with relatively high humidity such as The Batang Toru Forest Area. Environmental conditions such as humid or wet, watery, shady and high rainfall support the growth of Araceae species. Araceae have an unique spadix inflorescence characteristic that protected by spatha. A study on Araceae in Batang Toru Forest Area has never been conducted, leaving the unknown status of the species diversity and distribuion. The aims of this study was to invent Araceae in The Batang Toru Forest West Block area. The study was carried out from July to September 2018. The exploration method were used to invent the Araceae along the existing track path. There were 34 species of Araceae belonging to 8 genera found in the study side. All of species, 25 of them were lived as terrestrial and 9 of them were as epiphytes. The genera with the most species are Homalomena (12 species) and the least are Pothos (1 species). Araceae can lived on the soil, stones, trees, riparian and pond. Araceae can be found at various altitude with high air humidity (73-99 %) and warm temperature (17-27 °C). Araceae also like acid soil (4-7), warm (19-27 °C) with various humidity (1.5-8).

Sphaeropsis sapinea (Fr.) Dyko & B. Sutton in Pinus sylvestris L. stands affected by long-term drought

Abstract In this study, the fruit bodies (pycnidial) colonization and spore presence of Sphaeropsis sapinea (Fr.) Dyko & B. Sutton on Scots pine (Pinus sylvestris L.) trees in stands affected by long-term drought in the Czech Republic were evaluated. A total of 520 cones at four sites were evaluated every 1.5 months from June 2019 to December 2020. The pycnidia of S. sapinea in relation to colonization by subcortical insects in inner bark and wood, and wood-decaying fungi a total of 340 trunks at 17 sites during the autumn of 2020 were also evaluated. Pycnidial colonization of S. sapinea on cones was significantly higher at the site with the highest air humidity and significantly lower in the sampling periods of June 2019, August 2019, and November 2019, which were characterized by low precipitation levels. S. sapinea spore presence on cones was significantly higher at sites in Bohemia compared to those in Moravia, in sites with higher air humidity, and in three consecutive sampling periods in March 2020–June 2020. Pycnidial colonization of S. sapinea on trunks was significantly positively dependent on the colonization of subcortical insects in both inner bark and wood, but not with the colonization of wood-decaying fungi. The results of this study show a positive relationship between high humidity and colonization by subcortical insects in inner bark and wood with S. sapinea on Scots pine.

The effect of light on the early growth wheat (Triticum aestivum L)

Triticum aestivum L is a cereal plant that grows optimally in a subtropical climate. In tropical climate wheat growth experieces various obstacles such as high air temperature and humidity, and intensity of light. Study of wheat conditions for the growth of this plant in tropical areas such as Indonesia is needed. This study aims to determine the effect of light on the germination, growth, and early development of wheat.this is an experimental research with two treatments, the first group was in normal light and the the second was without light. Each treatment was carried out using 30 replications. The analysis was carried out by comparing the average value of plant length and plant morphology from eight days of observation on two kinds of treatments. The results showed that there were differences in plant height in the two treatments. The average plant height on the 8th day in normal light treatment was 9.76 cm, while the average plant height with the treatment without light was 10.1 cm. Observations of growth on the morphology of wheat plants showed that plants with no light treatment experienced a slowdown in the opening of the second leaf, had a paler color and thinner leaf blades, compared to plants grown with light treatment. The absence of light accelerates the germination process and increases the height of wheat plants, but at a later stage it can slow down the development of these plants.

A sensitive and ultrafast FA0.83Cs0.17PbI3 perovskite sensor for NO2 detection at room temperature

Nitrogen dioxide (NO 2 ), as a common air contaminant, can cause human asthma and other respiratory diseases under a ppm-level atmosphere. Currently, most metal oxide semiconductors sensors usually work at a high temperature, which hinders its practical application. Therefore, to develop an efficient sensor with good stability and sensitivity is urgent for NO 2 detection at room temperature. Herein, we report a FA 0.83 Cs 0.17 PbI 3 (FACs)-based perovskite sensor via a simple one-step spin-coating method under ambient atmosphere. The FACs-based sensor exhibits a sensitive response to NO 2 gas, low detection limit of 0.14 ppm and good reversibility as well as selectivity. The response/recovery time for the detection of 10 ppm NO 2 is only 2/22 s, which surpasses the vast majority of sensors. Moreover, the FACs-based sensor also displays excellent stability. No morphological and structural changes occur, when FACs film is successively placed in a high-humidity air (50–60 %) without any encapsulations for three consecutive days. Benefitting from the superior response and stability, the FACs-based sensor in this work may open up a new avenue for high-performance sensor for the practical detection of NO 2 at room temperature. • Sensor is prepared via one-step spin-coating method in ambient atmosphere. • FACs-based sensor exhibits an excellent sensing performance to NO 2 gas at room temperature. • The response/recovery time for the detection of 10 ppm NO 2 is only 2/22 s at room temperature. • FACs-based sensor displays a superior stability in high humidity air without any encapsulation.

Study the Performance of a Novel Desiccant Heat Exchanger

Conserving energy and reducing emissions has become a global consensus. However, most air conditioning systems are highly energy-consuming, affecting global warming and the ozone layer because they use chlorine and fluorine refrigerating fluids. Evaporative cooling systems are one of the most important environmentally friendly air conditioning systems with low energy consumption. However, their performance is negatively affected by the high humidity of the inlet air. One of the solutions to control the relative humidity of the inlet air is using desiccant material. In this paper, a silica gel-coated heat exchanger was designed and constructed as a dehumidifying unit. The effect of airflow rate, hot water flow rate, cold water flow rate, and regeneration temperature on the system's performance has been studied. It was found that increasing the hot water flow rate improves the removing moisture from the desiccant. However, increasing the hot water flow rate has a negative effect on the thermal performance of the heat exchanger. The effectiveness of the heat exchanger was 53% in the regeneration phase and 52% in the cooling phase for the outside air temperature of 40 ºC, W=20 g/kg, and an airflow rate of 0.48 m³/s. From the results shown above, it was noticed that the system could work efficiently in hot and high humidity climates and be used in Iraqi weather.

Influence of Agronomic Factors on Mycotoxin Contamination in Maize and Changes during a 10-Day Harvest-Till-Drying Simulation Period: A Different Perspective.

Agronomic factors can affect mycotoxin contamination of maize, one of the most produced cereals. Maize is usually harvested at 18% moisture, but it is not microbiologically stable until it reaches 14% moisture at the drying plants. We studied how three agronomic factors (crop diversification, tillage system and nitrogen fertilization rate) can affect fungal and mycotoxin contamination (deoxynivalenol and fumonisins B1 and B2) in maize at harvest. In addition, changes in maize during a simulated harvest-till-drying period were studied. DON content at harvest was higher for maize under intensive tillage than using direct drilling (2695 and 474 μg kg−1, respectively). We found two reasons for this: (i) soil crusting in intensive tillage plots caused the formation of pools of water that created high air humidity conditions, favouring the development of DON-producing moulds; (ii) the population of Lumbricus terrestris, an earthworm that would indirectly minimize fungal infection and mycotoxin production on maize kernels, is reduced in intensive tillage plots. Therefore, direct drilling is a better approach than intensive tillage for both preventing DON contamination and preserving soil quality. Concerning the simulated harvest-till-drying period, DON significantly increased between storage days 0 and 5. Water activity dropped on the 4th day, below the threshold for DON production (around 0.91). From our perspective, this study constitutes a step forward towards understanding the relationships between agronomic factors and mycotoxin contamination in maize, and towards improving food safety.

Профессиональный риск для горнорабочих при многофакторном воздействии производственной среды

Preserving the health of the employees, reducing morbidity and maintaining the quality of life of people employed at the mining enterprises are related to the priority tasks of the state social policy in the field of professional activity. And the extraction of raw materials and the production of light metals are important tasks in the industrialized country. One of the risk groups, which is under the constant negative impact of a complex of the unfavorable production factors, includes miners engaged in the extraction of carnallite for the production of metallic magnesium. Specific working conditions lead to the development of a number of diseases among the personnel of the mining enterprises and can reduce life expectancy. When assessing the working conditions of miners, it is advisable to consider the factors of the natural and industrial environment at the mining sites, even if they belong to the category of low intensity. The peculiarity of the natural environment of carnallite sites is due to high air humidity and the formation of hydroaerosols, which contribute to the active sorption of dust components in the course of work. An important element in assessing the impact of industrial environment factors on the human body is the analysis of its physiological reactions during a work shift, especially the process of fatigue formation, since it is this state of a person that can cause incidents. Health risk assessment of the miners has now acquired particular relevance. The most acceptable approach involves taking into account the production environment and determining the class of the working conditions. And the subsequent risk calculation should only confirm these primary data and focus on ensuring occupational safety.

Depth distribution and chemistry of salts as factors controlling tafoni and honeycombs development

Salts play a pivotal role in the processes forming tafoni and honeycombs but only few studies have focused on their areal and depth distribution. An X-ray diffraction, rock leachates chemistry, and evaporation front depth were combined to get a deeper insight into factors controlling salt composition and distribution. Five sites representing various lithological and/or climate conditions were studied. The data show that salt composition is a result of the interaction between chemical compositions of rainwater and lithology. Gypsum was found to be a major salt on all sites with halite dominating in arid sites. On humid sites the high relative air humidity prevents its precipitation. Gypsum and epsomite dominate also on sites where the rock contains a considerable amount of pyrite. Alum-(K) occurs in quartz sandstones when affected by acid rain. Some ions probably occur in residual brines, rather than precipitated salts (CaCl in arid or NaCl in humid sites). On arid sites, the salt content in the tafoni backwalls is 4–20 times higher than in outer walls and rapidly decreases with depth which is consistent with shallow evaporation front in backwalls. The low salt content in the outer walls reflects the dilution effect of surface runoff after rains and the infiltration of water through the outer walls toward depth. In two humid sites, on the contrary, no differences were found between the salt content of the backwalls and the outer walls. At one site the data shows that the whole surface of tafoni serves as the salt precipitation zone and tafoni are thus recently degrading. The honeycomb site differs from all tafoni sites since the honeycombs are mostly protected from rain runoff, which prevents the washing-out of salts even from the outer walls.

Variability of soybean yield and seed quality depending on environmental hydrothermal factors

Variability of soybean yield and seed quality depending on environmental hydrothermal factors

Unencapsulated CsPbClBr2 Film Photodetectors Grown by Thermal Vacuum Deposition Exhibit Exceptional Environmental Stability in High-Humidity Air

Unencapsulated CsPbClBr₂ Film Photodetectors Grown by Thermal Vacuum Deposition Exhibit Exceptional Environmental Stability in High-Humidity Air

Ecology and microhabitat model of long-tongued fruit bat Macroglossus minimus (Chiroptera: Pteropididae) in karst ecosystem of Klapanunggal, Bogor, West Java, Indonesia

Abstract. Wibowo AA, Basukriadi A, Nurdin E, Benhard G. 2022. Ecology and microhabitat model of long-tongued fruit bat Macroglossus minimus (Chiroptera: Pteropididae) in karst ecosystem of Klapanunggal, Bogor, West Java, Indonesia. Intl J Trop Drylands 6: 11-15. Karst ecosystem is an important habitat for Chiroptera, including the long-tongued fruit bat Macroglossus minimus (E.Geoffroy, 1810) that feeds on nectar. While Klapanunggal is a karst ecosystem located in Bogor, West Java, Indonesia, Klapanunggal has potential Chiroptera habitat. Here, this study aims to assess and model microhabitat covariates that contribute to the density of M. minimus in Klapanunggal. The sampling sites in Klapanunggal karst covered forest, plantation, and settlement sites. Measured microhabitat covariates including tree covariates (canopy covers, Normalized Difference Vegetation Index/NDVI, diversity, height), air humidity, distance to a river, and distance to a cave. The microhabitat model was developed and measured using Akaike Information Criterion (AIC). The result shows a high density of M. minimus was observed in plantation site (13.96 inds./100 m2, 95%CI: 4-23 inds./100 m2), followed by the forest (7.13 inds./100 m2, 95%CI: 1-14 inds./100 m2), and settlement sites (4.7 inds./100 m2, 95%CI: 1-10 inds./100 m2). Based on AIC values, the best model explaining the microhabitat covariates that have positive effects on the density of M. minimus were tree diversity and NDVI. While humidity and distance to river covariates have negative effects. Density of M. minimus was positively correlated with increase in tree diversity (AIC= 14.73, r= 0.93) and NDVI (AIC= 22.09, r= 0.18) values. The limiting factors of M. minimus populations were high air humidity (AIC= 2.85, r= 0.99) and increase in distance to river (AIC= 20.85, r= 0.46). To conclude, the conservation of M. minimus particularly the karst ecosystem should emphasize increasing tree diversity.

Hydathodes in ferns: their phylogenetic distribution, structure and function.

Ferns are the second largest group of vascular plants and are distributed nearly worldwide. Although ferns have been integrated into some comparative ecological studies focusing on hydathodes, there is a considerable gap in our understanding of the functional anatomy of these secretory tissues that are found on the vein endings of many fern leaves. In this study, we aimed to investigate the phylogenetic distribution, structure and function of fern hydathodes. We performed a global review on fern hydathodes and their phylogenetic distribution, carried out an ancestral character state reconstruction, and studied the structure, guttation and elemental composition of salt residues of eight species, and the diurnal patterns of xylem pressure of two species. Hydathodes are known from 1189 fern species, 92 genera and 19 families of 2 orders, Equisetales and Polypodiales. Stochastic character mapping indicated multiple gains and losses of hydathodes at the genus level, occurring especially during the last 50 million years of fern evolution. Hydathodes were located on the adaxial leaf surface and characterized by a cytoplasm-rich, pore-free epidermis, and became functional for several weeks after nearly complete leaf expansion. In two species, positive xylem pressure built up at night, potentially facilitating guttation. Guttation fluid was rich in Ca and often Si, but also contained P, Mg, Na and Al. Stochastic character mapping and the structural and functional diversity of hydathodes indicate multiple origins, and their presence/absence in closely related taxa implies secondary losses during fern evolution. Positive xylem pressure and high air humidity play an important role as drivers of guttation. Hydathodes may contribute to the regulation of leaf nutrient stoichiometry by the release of excessive compounds and minerals other than waste products, but the presence of essential chemical elements in salt residues also indicates possible leakage.

Surface Sublimation/Evaporation and Condensation/Deposition and Their Links to Westerlies During 2020 on the August‐One Glacier, the Semi‐Arid Qilian Mountains of Northeast Tibetan Plateau

AbstractTo identify the links between glacier sublimation/evaporation, condensation/deposition and westerlies, in situ meteorological data and surface roughness lengths during 2020 were collected on a mid‐latitude and westerlies‐controlled glacier in the northeast TP. Snow or ice sublimation rate was generally believed to be higher during the weather conditions with stronger winds and drier air, while our results showed that the strong westerlies in winter brought the driest and windiest conditions, but did not cause the most sublimation loss due to extremely low surface temperature. The weakening of westerlies intensity and the increased precipitation during summer suppressed the sublimation and evaporation for the low wind speed and high air humidity, and condensation or deposition was more possible during the nighttime of summer together with the radiative cooling on surface and enhancement in atmosphere stability, while annual condensation and deposition were only 1.3 and 14 mm, respectively, which were negligibly small compared to sublimation (115 mm). The westerlies in autumn and spring strengthened sublimation with relatively stronger winds and drier air than summer and higher temperature than winter. Sublimation was more intense in autumn (41 mm/0.4 mm d−1) and spring (35 mm/0.4 mm d−1) than winter (23 mm/0.2 mm d−1) and summer (17 mm/0.2 mm d−1). Therefore, westerlies may not be the most crucial driver of glacier sublimation as its effect may be restricted by low surface temperature during a very cold weather.

Two-stage evaporative cooling system with composite activated carbon fiber dehumidification

A two-stage evaporative cooling system with composite activated carbon fiber dehumidification is proposed. After the first evaporative cooling, the high humidity air is dehumidified in the internally cooled desiccant bed, then sent to the second evaporative cooling unit for further cooling. The evaporative cooling unit adopts the fiber wet curtain as the cooling medium. In the internally cooled desiccant bed, composite activated carbon fiber (ASL) is filled, and copper tubes are arranged for cooling/heating. ASL is prepared of activated carbon fiber (ACF) impregnated with silica sol and LiCl, with an equilibrium dehumidification capacity can increase 3.1 times higher than ACF. The average dehumidification capacity of the desiccant bed reaches 5.59 g/g, and the relative humidity of the outlet air decreased to below 50% in 46 min. In the two-stage evaporative cooling system performance experiments, the supply air temperature is 3.1–4.8 °C lower than the single-stage, and the humidity ratio is 0.42–2.66 g/kg lower. The cooling capacity Qc,e, cooling efficiency ղTwo-stage, and coefficient of performance (COP) increases with increasing inlet air temperature and decreasing inlet air relative humidity, air velocity, and cooling water temperature. Qc,e, ղTwo-stage, and COP of the two-stage evaporative cooling system can reach up to 3757.5 W, 1.78, and 10.8, 808.8 W, 0.64, and 2.33 larger than these in the single-stage.

High nitrogen‐fixing rates associated with ground‐covering mosses in a tropical mountain cloud forest will decrease drastically in a future climate

Abstract Tropical mountain cloud forests (TMCF) harbour a high bryophyte (mosses and liverworts) biomass and diversity. Furthermore, the high air humidity makes these forests well suited for bryophyte‐associated nitrogen (N2) fixation by cyanobacteria, providing a potentially important source of N input to the ecosystem. However, few studies have assessed bryophyte‐associated N input in these ecosystems, and these have focused on epiphytic bryophytes, whereas abundant ground‐covering bryophytes have not been included. In this study, we quantified N2 fixation rates associated with bryophytes, focusing on ground‐covering mosses in a neotropical mountain cloud forest. Furthermore, we identified the effects of climate change (higher temperature 10 vs. 20° and lower bryophyte moisture level 50% vs. 100%) on N2 fixation across bryophyte species and groups (mosses and liverworts). Nitrogen fixation rates associated with ground‐covering moss species were up to 2 kg N ha−1 year−1, which is comparable to other N inputs (e.g. N deposition) in tropical cloud forests. Furthermore, changes in temperature showed little effect on N2 fixation, but low moisture levels significantly suppressed N2 fixation activity. We found low N2 fixation activity associated with the investigated liverworts. Our results demonstrate the importance of ground‐covering, moss‐associated N2 fixation as a N source in tropical cloud forests and suggest that predicted future declines in precipitation in these systems will reduce N inputs from bryophyte‐associated cyanobacteria. Read the free Plain Language Summary for this article on the Journal blog.

Experimental investigation on water vapor permeability in porous dust layers on cold fin surface of heat exchanger

Removing the dust layers on a heat exchanger of air conditioner by impelling the permeated water to freeze and expand is a promising technique to avoid the heat transfer performance deterioration, and the key for this technique is to permeate enough water vapor by controlling the operation conditions of air conditioners. The purpose of this study is to obtain the influence law of operation conditions on the water vapor permeation mass in dust layers, and experimental investigations are carried out covering the representative conditions of air conditioners, e.g., the inlet air relative humidity ranging from 15% ∼ 90% and the fin temperature ranging from 2 ∼ 8°C. The results show that the water vapor may preferentially permeate into the pore channels constructed by adjacent dust particle aggregates, and the water vapor condensation may block the pore channels and prevent the further water vapor permeation. High relative humidity of inlet air or low temperature of fin facilitates the water vapor permeation, and the maximum water vapor permeation mass increased by 21.8% and 20.6% respectively as the relative humidity increases or the fin temperature decreases, while the water vapor may not permeate into the porous dust layer if the relative humidity is lower than a threshold value. It can be concluded that, in order to improve the dust removal effectiveness by the enhancement of water vapor permeation, the fin temperature should be controlled adaptively according to the relative humidity in the actual operation environment of air conditioners.