Towards sustainable landscape irrigation using novel design of water collecting systems from atmospheric humidity condensation

The paper proposes an innovative improvement to the water collectors from atmospheric humidity condensation by introducing non-hydrophobic substances to speed up the water condensation and the dropping off process using simple technology, inexpensive and with high quality materials with the �nality to favor sustainable irrigation in regions characterized by water resources scarcity favoring greening generally. The innovative collector’ design and experimentation conduced con�rm the possibility to collect water from air humidity in different regions with reduced rain days as semi desertic zones enhancing the gain of deserti�cation process, harvesting water in urban landscape, in vertical greening and roof gardens. The �rst principal innovative aspect of the novel design collector is the fast capacity of condensation caused from the method of design of the used materials and fast capacity of releasing water collected to contrast the undesired evaporations. The second innovative aspect is the reduced volume to permit a diffused and unexpensive implants which can be distribute suitably on the targeted landscape. Reduced costs and simplicity of fabrication announce real possibility of use in underdeveloped and poor countries to increase vegetation diffusion �rstly and contributing on sustainable agriculture and architecture.


Introduction
Water scarcity is one of the most prominent problems facing the countries of the world, especially in light of global warming and low levels of precipitation, which makes the water harvest in the form of rainwater collection and the creation of water condensers that transform the fog and water vapor suspended in the atmosphere an urgent necessity, In light of this, many efforts have been activated in water harvesting, especially in countries that suffer from a great water scarcity, such as some Mideast and African countries.The condensation of water vapor from the atmosphere, converting it into drops of water, collected to satisfy many purposes of irrigation and the daily human use.any experimentations in this sense were done and the issue has a consolidated literature encourages the research in this eld.The propose of this paper is to introduce innovative elements to permit a large diffusion reducing costs rstly and increasing the capacity of these implants.United Nations classify water as the main issue of a sustainable socio-economic development, Water, standing to United Nations reports climate change mitigation and resilience has the core that colligates society and the environment [1] United Nations.

(2018).
This research combines technical development and improving the novel design of water collecting systems with existing experimentation and relative literature.The novel aspect is related on the reduced and variable dimensions, the introduction of advanced materials and physical principles that govern the condensation process.Basic science demonstrates that the dew point of the vapor of water in an environment depends on several elements that must be satis ed at the same time: the presence of water vapor and decreasing of temperature and smooth surfaces.The continuous deserti cation of potential agricultural areas and landscapes in semi desertic Countries as Jordan induces us to think on how to improve sustainable systems characterized by reduced costs and simplicity of construction to permit a real diffusion.These systems should be used in many modes as urban landscape irrigation, mini agricultural activities and to irrigate trees in zones characterized by real di culty to irrigated.The proposed systems do not need manutentions and are ideated to be passive systems without any carbon footprints.Together strategies that focuses on classifying natural types of vegetation diffused in very hard climatic zones to be employed in greening recovery in Jordan and other semi desertic countries.Collecting vegetation types and their persistence to hard climate constitute the rst step in ghting deserti cation in sustainable mode and is based on observations related to natural characteristics of some suitable vegetation that among the years demonstrated a high capacity of persistence in very hard conditions.The use of this type of vegetation could produce many bene ts as relaying the process of deserti cation, stabilizing landscape, giving the possibility to some cities to have sustainable urban greening.The low cost, the unneeded maintenance and the introducing passive irrigation favor the access of developing countries on environmental policies that contribute actively on reducing the global warming and deserti cation processes.

Literature Review
The most famous effort related to develop systems able to harvest water from air humidity is the Warka Arca project developed by Arturo Vittorio with his team by designing a water harvesting unit called (Warka Water Tower) which the main function of it is to harvest the water by the atmospheric humidity absorbed by a surface called mesh so that could help providing the community of 100 liters of water per day.the tower mainly consisting of a polyester mesh supported by Bamboo frame (Fig 1), this mesh could catch the humidity and condense it to gain a waterdrops (Fig 2) which fall into a reservoir found at the bottom of the structure and a fabric canopy could shade the area around it and used by people to set under it.
The e ciency of this type of network is reduced and causes the loss of a quantity of accumulated water is the rebound of the drops that accumulate on the net with the owing air.Many researchers tried to improve the e ciency of the net and develop its parts e ciency.Four factors that determine the e ciency of the humidity collectors, which are: wind velocity, liquid fog water content, droplet size distribution, and net characteristics [2] Warka Water Inc. (2017).
In different regions researchers developed projects and devices with targeting on harvesting water from air humidity, these devices use the universal principle of densi cation.Dehumidi ers utilized as water extraction devices distributed on different areas in Bahrain con rmed the economy of this method of water collection in comparison to other nonconventional methods [3] (Nidal A. Dahman et Al. 2017).These systems are active once to allow the water vapor densi cation among the use electric device that aspire and reduce air temperature shows the importance of this type of research for some Countries.
Different typologies of collectors presented in Hasila Jarim et Al.2020 [4] are characterized by large dimensions with several problems related to the use of the mesh and di culties related to the degradation of parts of collectors, (see Table 1).Various types from traditional passive implants (without the use energy) to those designed in active mode certi cate their importance and the need of development their potentiality.At now it is impossible to imagine their large use rstly for the elevate costs and to technical di culties of production and installation.The targeted proposed design in this paper is based on the use of micro applications that permit large range diffusion [5] (Aldeek ZAO.2020).

Discussion
As mentioned in literature review the topic enjoys large interesse and presents a potential tool to harvest and collect water in those Countries with scarce water resources.The challenge in this paper is to transform traditional collectors in novel water collecting systems that permit a capillary diffusion, reduced costs and volumes alloying their simple management.The importance of developing this type of technology its contribution in many life sectors: obtaining potable water in these zones where water sources are exposed to high level of pollution or diffused infections, contributing to a micro agricultural system in remote regions, incentivizing the stop of deserti cation in many semi-arid regions and nally giving a valid contribute on climate change.For many years' attentions are focused on mega projects in emerging Countries as motor of sustainable development forgotten that the sustainable development must take into consideration the diffused and capillary production in remote regions.The result is the continuous internal and external immigration.Micro projects that use advanced technologies but simple to be understood and actuated present the base for the recovery strategies in many sectors, [8] Aldeek ZAO, 2020.
The proposed novel design of water collecting systems is based on this idea and concept, it uses simple methodology combined with advanced materials to provide portable implants which can be easily managed.As will be explained in successive parts of this work we focused on major comprehension of factors that govern the condensation and dropping process, it is necessary that materials used in the construction of our novel water collecting systems correspond to some criteria as: High capacity to exchange heat rapidly with surrounding environment, (high heat emissivity).
Presents smooth surfaces to favor the veri cation of the dew point, (Wettability).
High capacity to release the collected water rapidly to contrast evaporations, (hydrophobic performances).
Use suitable design con guration that favor the process of densi cation and collecting.

NOVEL DESIGN OF WATER COLLECTING SYSTEMS FROM ATMOSPHERIC HUMIDITY CONDENSATION
The structural and surface characteristics of the proposed collector must re ect the above-mentioned performances.The proposed water collector model consists of the main elements represented by the collector net responsible for condensing the droplets carried with wind or fog that lends through the network, and a water tank centered at the bottom of the model.The major element of design in the proposed system is to change materials used in the classic nets.Since now we must specify that atmospheric conditions play important role in the design process, it is possible to classify environmental conditions in three types: high mountains characterized by diffused and continuous wind and fog, hot humid zones characterized by high level of saturation (high humidity and temperature) and arid and semi-arid zones characterized by summer-night dew formation.The indicated zones have as commune element the low level of precipitations due different reasons.Traditional elements used in hot-humid zones have not the capacity to transform humidity from gas status into liquid one.As shown in Figure 2 classic materials absorb humidity from atmosphere this means that works in just high level of saturation.
The time for this process is long and reduce sensibly the capacity of the net to collect water.While traditional elements used in very high mountains are designed for the speci c geographical conditions and cannot function in semi or arid zones.
The novel system must combine other performances of the used materials, as shown in Figure 3 a solid surface has major capacity to attract humidity from the atmosphere.This capacity is referred to physical principles related to the conditions of the dew point veri cation.The solid surface as the anodized aluminum or other metal elements, (see Table 2) lose heat rapidly respect the environment satisfying the rst condition, the smooth surfaces generally satisfy the second dew point condition.
The above-mentioned conditions are necessary to be employed in the realization of our novel system.Figure 4 presents the concept of realization.The introduction of metallic elements increases the quantity of water collected because together the absorption of water as in classic meshes because adds the water quantity collected be the dew point veri cation.Adding to these metallic elements a hydrophobic capacity we will reduce the evaporation loss of collected water on the net.
The innovative part is the design of the grid' surface and the introduction of a hydrophobic performance obtained by the use of substances as nano ceramic, liquid ceramic or other suitable paints.The Nano Ceramic which has the advantage of not interacting with water and it does not alter the properties of the materials with which it is painted, its function is only to accelerate the fall of the droplets after condensation.
On the other hand, the materials used in the novel design of water collecting systems must re ects the desired performances.It can be classi ed in three steps, the rst the high capacity of absorption and wettability, the second the high capacity to lose heat in manner that favor the condensation rapidly.The third is the capacity to release the accumulated water rapidly.Last element but not the least is the design' con guration of the proposed systems, a mesh disposed in horizontal mode do not bene t from gravity to release condensation rapidly, the very smooth surface does not attack the surface tensity of the water droplets for example.

WETTING PHENOMENA AND THERMAL RADIATION CAPACITY
Wettability and super-wettability happen once a water drop is placed on a surface, it forms a sphere or wets the surface completely and called "super-wetting".Antiwetting and super-anti wetting are the capacity of a surface to release water drops formed by condensation process [6] (Durand et al., 2011).Wettability and anti-wetting have particular importance when studying phenomena related to heat transfer and humidity applications generally.In our case these concepts guarantee the functionality of our novel system.The high wettability in our case is guaranteed from the selected materials having high capacity to lose heat by radiation (heat emissivity).
The process of wetting phenomena is related to thermal radiation capacity which standing to the Stefan-Boltzmann Law [9] (Nelly Durand et Al 2011), compared with the radiation of heat from an ideal "black body" with the emissivity coe cient (ε) = 1. the emissivity coe cient (ε) for some common materials can be found in the Table 2.It is note that the emissivity coe cient (ε) for some materials varies as environmental temperature are changed [10].Table 2 shows the emissivity of some materials at 26.85 C. The emissivity expresses the capacity of certain material to lose heat resulting colder than the environment.This propriety determines the possibility of the condensation on the surface in question.At lower temperatures from zero to 26 grads C the behavior of surfaces may be different.To understand better this aspect, we conduced some Laboratory tests which consists in exposing different materials with same geometric measures without altering the bulk density to zero C temperature and with environmental temperature 26 C in the same method and time of exposing.Measuring their surface temperature in progressive time intervals in this way materials that reach faster the equilibrium with surrounding environment will result the better than the others because have the highest level of exchanging heat at low temperatures, (see Table 3).

After 1 minute
Temp.

After 10 minutes
Temp.
After 20 minutes Temp.
After 60 minutes Material Temp.

After 1 minute
Temp.

After 10 minutes
Temp.
After 20 minutes Temp.
After The capacity of the selected material for construction of the proposed system depends on its wettability, availability, and durability.

HYDROPHOBIC PHENOMENA
The industrial applications of superhydrophobic performances are a consolidated reality especially in eld of paints production.These applications noted as: anti-fog coating, anti-freeze surfaces, oil and water separation, anti-bacterial surfaces are applied in medical and industrial camps to prevent bacterial accumulation and to improve performances against corrosion of metals and implants.[11] (Gh. Barati Darband et AL.2020).Hydrophobic phenomena consist in anti-wetting surface capacity to prevent water accumulation.In nature, the lotus effect means that water drop on a lotus surface showing contact angles of approximately 147° (cutting angle) caused from the surface con guration [12] (Latthe S. S. et AL.2014).
Lotus effect describes the behavior of the superhydrophobic surfaces where water contact angle is greater than 150° with low sliding angle, under 10°.Attract important research interest related to the potential anti-icing properties.Applicability in daily life issues, in agriculture, and in many industrial processes as: antiadhesive coatings, self-leaning materials, antifouling, anticorrosion, [13] (L.YU et Al.).The use of superhydrophobic paints and other industrial applications as the use of nano ceramic on surface simulates the lotus effect and can be easily used in the proposed system.

The Innovative Design Of The Grid' Surface
The proposed prototype takes into consideration di culties to achieve water harvesting from humidity directly.Major di culties of the dew point veri cation related to particular conditions as shown in Table 4 which determine speci ed temperature, speci ed relative humidity level and particular surfaces.As success in particular types of vegetations that bene ts from humidity absorption during night hours.These vegetations resolve the problem by the continuous leaf reduction of temperature caused from their morphology, and by the direct absorption of humidity mixed in air see (Fig. 7).Generally, as shown in Fig. 7a leave has two different surfaces the upper is characterized by smoothness favoring the condensation while the lower is characterized by a rough one to maximize the dew absorption from nearest air.This concept is also explained by Alfred W. Bennett "Although gardeners universally maintain that growing plants have the power of absorbing water through their leaves, both in the liquid and the gaseous form, in addition to the power of suction through the roots,".In his "Text-book of Botany" (English edition, p. 613), [14], Sachs says: "When land-plants wither on a hot day, and revive again in the evening, this is the result of diminished transpiration with the decrease of temperature and increase of the moisture in the air in the evening, the activity of the roots continuing; not of any absorption of aqueous vapour or dew through the leaves" [14].
These two positions seem to be in contradiction about the method of absorption of dew and water vapour from air but evidence that it is possible to absorb dew and water vapour from air and the di culty of trees to bene t from the collected water by leaves.In fact, when we study some particular trees, we note that the collected water by leaves is canalized and directed into the three roots.From both a rmations we can bene t in our novel collector design in manner that surface of parts used in the condenser realization must be designed to re ect this aspect.From our research suitable materials as metallic strips, strips of cooked clay and plastics constitute basic elements for the condenser construction.To satisfy the absorption and dew condensation together it is necessity to use a multi-layer strategy.The level of relative humidity and day temperatures determine the construction type of collector.
However, from experimentations we noted that the use of the clay could satis ed in different levels of temperature and relative humidity due its high performance to absorb and to favor dew condensation.It is noted the high capacity of cooked clay and ceramics in general to absorb water due the presence of micro canals (porosity) which ensures the dew and water vapour absorption.On the other hand, ceramics generally, do not release the absorbed water easily.This aspect leads that the use of special paints will be the way to optimize the process in our novel collector (see Table 4).4 and chart 1 show that materials which satisfy both conditions of absorption and condensation at the same time are ceramic derivates.This fact changed the initial hypostasis to use just metallic.The rst prototype is realized from a structure that support the metallic strips, see Fig. 8. Experimentations con rmed that the prototype in Fig. 8 has a very good functionality in summer season where the formation of dew accumulation and sensible temperature daily reduction are very frequent.

FIRST PROTOTYPE CONSTRUCTION AND EXPERIMENTATIONS
Initially the collection mesh consists mainly of intersecting metallic strips with high emissivity (radiative capacity) to lose heat by radiation in manner to favor the condensation process at targeted temperature variations.The surface of these strip is elaborated to favor the anti-witting capacity.This elaboration could be obtained in different modes as the use nano-ceramic paints or to be designed among the introduction of micro canals of the surface using for example the laser cutter performances.From testes we reached the convention that the novel collector must have good performance in all seasons that present scarcity of precipitation in semi and arid zones (from March to November), it is noted that vapor saturation and week rains in these zones are frequent.To improve our initial collector, it is painted with dark color the with the nality to satisfy the targeted function in all seasons.
From testes conducted to determine which materials to be used in the proposed novel system results that the use of a metallic mesh painted with liquid ceramic, nanoceramic, nanographene or any other oil paint could guarantee the targeted performances of emissivity to favor dew condensation.The prototype, thin, is painted with nanoceramic (to favor the anti-wettability performance), which is the commune technology used to conserve cars because results cheapest, easy to realize and does not need maintenance.Tables 2 and 3 shows that it is possible to use a variety of sustainable materials.In our case we selected strips of aluminum for the facility of prototype realization, many other materials should be suitable and can be use with satis ed results as strips of iron or P.V.C or plastics.

PROTOTYPE
The design of the prototype structure takes in consideration the operations of realizations, painting, nanoceramic application and testing.It is realized from light iron structure, (see Fig. 8).The structure can be realized in many other con gurations that result more suitable for the targeted uses.Dimensions and shape can be modi ed in relation to the site where will be installed.

SOLID ELEMENTS ADOPTED TO ACHIEVE THE WETTABILITY
As mentioned in 5.1 longitudinal metallic strips are used to realize the wind resistance net and to attract humidity from air.These strips are disposed vertically to use better the gravity in the water droplets dropping off, horizonal elements are used to organize the net.The nanoceramic application once time completed the installation and painting of the metallic strips net, (see Fig. 8).

DEVELOPED PROTOTYPE CONSTRUCTION AND EXPERIMENTATIONS
During the experimentation in which was in July 21, in Rihaba (a fraction of Irbid in Jordan) the major dew avenues nearest ground surface which induced to modify the initial prototype in a horizontal one more suitable for this condition.Figures 9.a and b show condensation happing process, the weight of water droplets favor their accumulation near ground.Thus, the nal version of the collector must take this aspect into consideration.Note that all condensation on surfaces will be evaporated in few minutes if not collected and nalized.

DEVELOPED PROTOTYPE CONSTRUCTION
From discussion in 5.1 the need of developing other type of collector suitable for weather conditions in the experimentation location.This type offers major horizontal surface to be suitable for the collection of dew condensation.It is characterized by simplicity of realization and low-cost materials.Realized in P.V.C panels which is a high emissivity material (see Table 2).As shown from documentation the novel collector is able to have very good performance.This type bene ts from week rains diffused in semi-arid zones contributing if nalized to ght deserti cation.As discussed before the capacity of condensation depends by two factors the rst is the high emissivity of the collector surface the other factor depends on how the surface releases condensation rapidly to be nalized for spontaneous irrigation, this factor is guaranteed by the anti-wetting capacity of the collector surface.Figure 10 shows the collector function during the experimentation.Figure 10.a shows the initial test, while Fig. 10.b&c show the concept of the nal form of the collector.Note that the form could simpli ed to be a simple panel for each tree or vegetation.(See Fig. 11).

TESTS AND MEASUREMENTS
The tests consisted in measuring the e ciency of the system in terms of water quantity collected.We selected three sites: the rst is the Yarmouk University in Irbid (Jordan), the second site is the Jordanian University of science and technology in Ramtha (in Jordan) and the third Rihaba (in Jordan) the test duration is 24 hours.

Conclusions
The presented novel collector puts together elements of high technology and traditional elements with the nality to increase its e ciency, diffusion and to reduce costs which is fundamental element when dealing with underdeveloped Countries where resources are very limited.Other relevant element that the whole system can be produces locally because does not need complex fabrication.The carbon footprint is reduced to zero, no electricity is required, and all functionalities are governed by the natural lows and physics.It could contribute to different sectors as sustainable agriculture and can help the development of land scape greening in our cities and nd application in roof gardens and vertical greening.Satisfying our principal target which to ght deserti cation and to contribute positively on climate change studying a technology that can be understood and built easily by all.

Figures
Figure 1 The Warka water details.Source [2] Figure 2 The water drops condensed against the collector mesh.Source [2].The behavior of water droplet of lotus leaf surface.Source: [13].

Figure 3 The
Figure 3

Figure 4 Proposed
Figure 4

Figure 5 Proposed
Figure 5

Figure 7 a
Figure 7

Figure 8 First
Figure 8

Table 3 .
Thermal Radiation Capacity at low temperatures based on Laboratory tests (Source the Author 2021).

Table 4
Water Absorption-Condensation Materials Performance (Source the Author 2021).

Table 5
comparison between types of collectors and the proposed novel collector (Source the Author 2021).

Table 6
Experimentation of the Novel Collector (Source: The Author21).