Rain Tower

Abstract

The rain tower is a prestressed, cable-stayed structure of hyperbolic shape with a steel core, (carbon) cables, and a cheap awning covering. An aero-thermal power plant is built into the tower, supplying electricity to the control system for the processes of condensation, coagulation, and vortex formation. Distinctive features are a supersaturated hot steam generator, a cloud droplet condenser, a spiral solar collector that allows to significantly reduce the required height of the structure due to an ascending vortex, a coagulation control system and matching the generated vortex with an undisturbed atmosphere. It is proposed to use pulses of acoustic shock waves as control actions, radiated by a phased array antenna in the form of a traveling wave. The signal parameters are selected according to the size of the colliding droplets in the vortex. The control device is mounted on the inside of the tower above the turbine of the aero-thermal generator. Impacts can increase the concentration of micro-droplets due to drift in an ascending vortex flow. This increases the likelihood of their collision and coagulation of cloud droplets, which turn into larger raindrops as they grow.

1. Introduction

The average annual temperatures in the south of the peninsula reach maximum values throughout the entire Eurasian continent—about 30°C [1]. In most of Arabia, precipitation is confined to the winter–spring period. In the Rub al-Khali desert, precipitation may not fall for more than five years. The climatic regime of Arabia is characterized by a large role of winds. In winter, the cold northern wind temal dominates, accompanied by strong squalls, sometimes short showers and thunderstorms. In spring and early summer, the south sultry wind simum is common, which carries large masses of sand, particles of which could theoretically play the role of coagulants, but the absence of condensate in the atmosphere does not contribute to the formation of clouds. A small amount of precipitation determines the lack of drainage of most of the territory and low availability of water resources.

Throughout most of the territory of Arabia, continental tropical air prevails throughout the year, causing an almost complete absence of precipitation. In the cold half of the year, the Arabian Peninsula falls under the influence of the subtropical maximum. During the summer, the entire region is occupied by an extensive baric depression centered in the Indus basin. The continental tropical air that forms here is very dry. Only on the coast, its moisture content in the lower layers increases greatly.

As can be seen from Figure 1, during the whole year, the circulation conditions of air masses do not favor precipitation. Even in coastal areas, air humidification is insufficient for the necessary saturation with moisture, which guarantees the condensation of water vapor and the coagulation of cloud droplets that form thunderclouds.

Figure 1.

Average monthly temperature and humidity in the UAE by months in an annual cycle https://www.climatestotravel.com/climate/united-arab-emirates.

Under natural conditions, convective clouds form due to high temperatures. They cause warm, moist air to rise from the colder ambient air into the atmosphere. The National Meteorological Center conducts regular cloud-seeding operations to increase precipitation. The target is convective clouds, which can cause precipitation and winds up to 40 km/h, which carry dust and sand.

Such a climate does not allow the sustainable development of new territories, leaving them unsuitable for human life. The UAE government faces the task of creating a controlled climate that will allow to live in comfortable conditions based on the use of modern methods of increasing humidity and the use of artificial intelligence (AI).

Heavy artificial rain occurred in several regions of the United Arab Emirates at the height of the July 2021 heat wave, when temperatures reached 48°C. They were provoked during tests of unmanned aerial vehicles capable of causing precipitation by applying an electric current to clouds without the use of chemicals. However, this approach to solving the problem of rainfall management is not stable. It does not increase the moisture content in convective clouds and is not able to form their artificial nuclei.

We have proposed a completely different approach to solving this problem. Its main difference lies in humidifying the atmosphere by artificially saturating it with seawater vapors, condensing them into micro droplets of cloud fog and a controlled process of coagulation of moisture droplets to the size necessary for the formation of thunderclouds at a given horizon height.

2. Project concept

Insufficient humidity and a low probability of the appearance of clouds suitable for sowing require an engineering solution to deliver to a given atmospheric horizon of cloud condensate, which will be sufficient for the formation of thunderclouds.

The proposed methods of control using the “Rain Tower” and artificial intelligence will allow us to form a stable ascending vortex flow that can deliver to a given atmospheric horizon the moisture necessary for the formation of a thundercloud.

In our opinion, this is the only solution capable of delivering moisture, which is not enough for the formation of thunderclouds, to a given height. The design of the tower directs steam-saturated sea air from the coast from the intake manifold to the seawater evaporator. Then, after its additional enrichment with moisture, it enters the cloud droplet condenser. At the outlet of the moisture condenser, the air saturated with micro-drops is picked up by an ascending vortex flow.

A stable upward vortex flow is formed by the passive infrastructure of the topology of the lower part of the “Rain Tower”. The pressure difference between the base of the tower and its upper cut creates a stable rarefaction and thrust in the body of the tower.

The shape of the “Rain Tower” is a two-focus hyperboloid of rotation that focuses the vortex flow into the working area of the aero-thermal power plant, where the wind turbine is located. The blades of this turbine have a special shape, due to the optimization of which the maximum coefficient of transformation of the rotational energy of the ascending vortex flow into the rotation of the electric generator is ensured. The electricity generated by the generator is used for life support and operation of all functional elements of the “Rain Tower” [2].

The movement of cloud micro-drops in a vortex flow is accompanied by their collision and enlargement. Coagulation of cloud droplets during their ascent to a given height maximally saturates the air with thunderstorm droplets, the size of which reaches that necessary for the formation of thunderstorm clouds and precipitation [3, 4, 5].

The vortex formation and coagulation control system is located behind the turbine of the vortex power plant on the inner surface of the duct in the upper part of the tower. This system contains special generators of ultrashort acoustic pulses, a system of phased arrays of ultra-wideband emitters that increase the coagulation rate of moisture droplets, prevent their drift to the axis of rotation, and control their radial movement in an ascending vortex flow.

Sequences of acoustic pulsed shock waves are generated by the AI of the control system while considering the environmental parameters. These sequences provide an effect on the coagulating droplets and the ascending vortex flow as a whole. Thanks to the control action, it is possible to set the pitch and speed of the rotational–translational movement of the ascending airflow, control the trajectory of large water droplets in the vortex body, and guarantee their growth to a given size at a given lifting height [6].

The control system for matching the vortex flow with the undisturbed atmosphere is located in the upper section of the Rain Tower. It forms a virtual air duct that ensures smooth evolution of boundary conditions during the interaction of the vortex with an undisturbed atmosphere. The virtual duct is formed by a sequence of concentric circular shock wave pulses that mimic the duct walls outside the Rain Tower housing.

The annular wave, like circles on water, expands, and as it spreads upward, the virtual duct turns into a diverging cone. As the shock wave attenuates, the walls of the virtual duct are eroded and a smooth alignment of the vortex flow with the undisturbed atmosphere is ensured.

Inside the virtual air duct, conditions are created for the propagation of short acoustic pulses that can affect coagulation processes outside the body of the Rain Tower. These influences prevent premature loss of moisture and guarantee its rise to the required height.

The friction of the vortex flow against the boundaries of the virtual air duct, together with the control acoustic action, completes the control of the process of raindrops coagulation and delivery of the thundercloud embryo to a given atmospheric horizon.

The appearance of a sufficient amount of moisture at the level of formation of thunderclouds (100–2500 m) will create the prerequisites for the growth of a thundercloud in natural conditions, and knowledge of the wind rose at a given horizon will make it possible to predict the time and place of rainfall [2, 7, 8, 9, 10].

3. The shape and design of the “rain tower”

The “Rain Tower” combines several functional units that sequentially saturate the air with the necessary moisture, transfer it from a gaseous to a liquid state, capture cloud micro-drops in an ascending vortex flow, and control the process of their coagulation into rain cloud drops.

3.1 Rain tower shape optimization

The “Rain Tower” is a hyperbolic, prestressed, cable-stayed structure with a steel core and a cheap tent covering, fixed along the perimeter with (carbon or Kevlar) cables, supported by a reinforced concrete perimeter with tubular columns on one side and with the support hoop of the lower part of the tower on the other.

The “Rain Tower” will consist of tent panels with low thermal conductivity, which are fixed around the perimeter with cables supported by the annular truss beam of the lower part of the tower on one side and the annular truss beam of the upper tower on the other side. The roof sheets will be overlapped and fastened with transverse bolts to intermediate external annular rafters [2].

As shown in Figure 2, the aerodynamic design of the tower and the solar collector is made according to the special geometry of a two-focal hyperboloid of rotation in accordance with the author’s certificates [11]. At the same time, the aerodynamic guiding structure of the spiral air ducts twisted around the central column both inside the base of the tower and the air intake is made in accordance with the author’s certificates (Figure 3) [12].

Figure 2.

Cable-stayed shaping structure of “rain Tower”.

Figure 3.

Air intake topology in the form of a two-start logarithmic spiral. (https://triptonkosti.ru/4-kartinki/logarifmicheskaya-spiral-kartinki.html)

The vortex turbine will be installed independently of the rope-stayed structure of the “Rain Tower” on a platform with a steel frame in its narrowest part, where the speed of the adiabatic updraft will be maximum.

In the case of a vortex flow, its velocity and the path of raindrops through the installation increase significantly. At the same time, the turbulent movement of air in the tower body and the part of the collector closest to it guarantees a reduction in friction due to the shape of the internal topology of the structure.

3.1.1 Existing data

The use of the proposed hyperbolic tower design makes it possible to achieve a lifting airflow velocity of more than 20 m/s (Figure 4) and form a moisture flow of up to 1350 mm/h, that is, 0.38 kg/(s_*m²) (with a diameter of 30 m in the narrow part of the tower and an ambient temperature of 22°C, the installation will be able to generate the upward flow of water with a volume of 267 kg/s), which is almost ten times higher compared with the use of known direct-flow ventilation shafts without a condenser and collector [5].

Figure 4.

The results of computer simulation of the plots of the velocities of ascending flows.

Figure 5 shows the temperature distribution at night. The heat from the surface of this calculation does not consider. It is known that if the ambient temperature is 26°C and the relative humidity is 50%, then the dew point temperature at normal atmospheric pressure is 15°C, which is observed at the top of the tower.

Figure 5.

Temperature gradient in the rain tower at night.

Figure 6 shows the distribution of pressure in the tower at normal atmospheric pressure and temperatures average 22°C during the day. As can be seen at the entrance to the spiral collector channels, the pressure is the highest, then there is a sharp decrease at the base of the vortex turbine, then it gradually increases at the outlet, but its pressure is still higher than atmospheric. This allows to generate rain cloud without bundles that determine its demolition of the wind at a sufficient distance.

Figure 6.

Pressure gradients in the rain tower during the daytime at 22°C.

The Figure 7 shows the vector distribution of air flows, it can be seen that colder air descends along the center of the tower and thus active convection occurs, that is, mixing of air masses with different temperatures. This may cause higher condensation and rising warm air. That shown here is the principle of operation Vortex turbine.

Figure 7.

Plots of ascending airflow velocities.

3.1.2 Analysis

The results of testing mathematical models indicate the positive direction research. Firstly, it is possible to achieve the transfer of large masses of moisture-saturated air to the height of the formation of rain clouds; secondly, the formation of oncoming flows in the vortex tower with a temperature contrast, thirdly, to ensure a high rate of air rise comparable to natural convection, fourth, the formation of droplets up to 100 microns, fifth, rapid condensation, sixth, stable controllability and seventh, scaling and coverage of the required area by placing a network of Rain Towers. Conducted computer experiments on the prototype of the digital twin of the tower confirm the vortex formation and estimates of the velocity of the updraft.

The computer experiments carried out on the prototype of the digital twin of the tower, confirming vortex formation and flow velocity forecasts, show the feasibility of conducting numerical experiments to optimize the parameters of a two-focal hyperboloid of rotation. Experiments should be carried out in all dynamic ranges of the observed parameters and, in frequency, combinations of environmental parameters (humidity, water and air temperature, vertical temperature gradient, wind rose at different horizons, atmospheric pressure, etc.).

Shape optimization will provide the maximum speed of the ascending vortex flow in the absence of control actions. This will give an estimate of the ranges of speeds of rotation of the turbine of the axial electric generator and the levels of electricity generated in different modes of its operation.

Numerical modeling of a loaded rope-stayed structure, considering the Rain Tower tent cover, will allow for strength calculations and architectural design with specified operating parameters (seismic resistance, requirements for monitoring structural elements and routine maintenance to ensure its performance, service life, and justified technical margin).

3.2 Structural components of the “rain tower”

It is well-known that a group of Israeli engineers, architects, and scientists, led by Prof. Dan Zaslavsky, worked on a project to use desert heat to generate electricity and water to increase the efficiency of an aero-thermal power plant [13].

The main components of the structure are a steam generator and solar collectors, in which the air in the tower is heated. Air enters through the tower’s air intake and is heated under a transparent solar collector adjacent to the tower. A temperature and pressure gradient arises, which provides the conditions for the formation of an upward flow. The density and temperature of the air at the base of the Rain Tower increase several times, which allows the use of modern energy conversion technologies, which, in combination with the use of updrafts, significantly increase the efficiency of the aero-thermal power plant.

The subject of research is the optimization of the parameters of the “Rain Tower” shape, which guarantees the maximum speed of the ascending vortex flow in the entire range of environmental parameters.

The control actions in the “Rain Tower” are based on the emission of acoustic signals with different parameters (dynamic and frequency ranges, spectra and durations, shape and steepness of the fronts of impulse actions, etc.) determined by the context of the tasks being solved (generation of superheated steam, coagulation in an ascending vortex flow, and formation of a virtual air duct).

3.2.1 Ultra-wideband acoustic transducer

All control actions in the “Rain Tower” are based on ultra-wideband transmission using the tunnel kinetic effect (TCE), discovered 40 years ago. The tunneling kinetic effect is the process of converting the transverse components of the velocity vectors of the molecules of the working medium into an axial component while maintaining the internal kinetic (thermal) energy of gaseous or liquid substances, which occurs when a strong electrostatic field is applied to the working medium.

If a porous permeable dielectric membrane is placed in a strong electrostatic field, an acoustic background appears in the form of white noise, since shock waves arise in the working medium (gas or liquid contained between the capacitor plates) as a result of the transformation of the transverse components, directed normal to the radiating surface from the velocities of Brownian motion to the axial component.

It is possible to control the generation of acoustic shock waves. It is enough to sum up a constant electrostatic field with a control action. A monopolar control signal does not lead to a polarity reversal of the electric field between the capacitor plates with a permeable electrode, which saves the acoustic wave generator from reactive losses [6].

This effect makes it possible to use the internal kinetic energy of matter and can be applied in almost all applied fields of science and technology. By observing the Brownian motion of particles at different temperatures, it is possible to establish a direct relationship between the average kinetic energy E _k of gas (liquid) molecules and the temperature T.

$$\frac{m{u}^2}{2}=\frac{3}{2}\mathit{kT}$$E1

where: T – temperature, measured from absolute zero and equal to the temperature in Celsius, increased by 273.16°; u - speed; k is a universal constant, the same for all substances and in any state (Boltzmann’s constant k = 1.3802 × 10–23 J/deg).

Kinetic energy can be represented as the sum of kinetic energies created by the velocity components along three mutually perpendicular coordinate axes X, Y, and Z as showed at Figure 8.

$$\frac{m{u}^2}{2}=\frac{m{u}_x^2}{2}+\frac{m{u}_y^2}{2}+\frac{m{u}_z^2}{2}$$E2

Figure 8.

Velocity field projections in the Cartesian coordinate system [6].

In a gas or liquid, molecules move at a certain speed in a straight line until they meet another molecule on their way. As a result of the interaction between them, the directions and magnitudes of the velocities of both molecules change. If one of the molecules at the same time reduces its speed, then the other moves faster. Of course, it is difficult to follow these fast-following changes in velocities first in one direction and then in the other.

The transformation of the transverse velocity components into a longitudinal one under the influence of a strong electric field leads to a redistribution of the kinetic energy of the particles in favor of the particles moving along the lines of force. For a particle with j degrees of freedom, this transformation will increase the kinetic energy of the working body along the lines of force of the electrostatic field by a factor of √j, since the transverse velocity components decrease due to refraction of the molecules.

Any porous permeable dielectric material containing a gas or liquid inside can be used as a converter matrix. When the required monopolar electrical signal is applied to the gas-permeable plates of the converter, kinetic tunnels begin to appear in the body of the working element. The conversion coefficient of the kinetic energy of a gas (liquid) in them is a function of the amplitude of the signal being supplied. As a result of the formation of these tunnels, the velocity vectors of the thermal motion of molecules are transformed in a plane perpendicular to the surface of the radiator (Figure 9).

Figure 9.

Cross section of an atmospheric TKE emitter [6].

Molecules with speeds above the speed of sound fly out of the body of the working element at hypersonic speed and, transferring their energy to the surrounding air, create shock waves; that is, matter is transferred in the direction of radiation. For air, these molecules have an elevated temperature and a free path of about 3–6 mm. Direct electroacoustic conversion, using the thermal movement of air molecules, guarantees an ultra-wide frequency band of the emitter f є (0–10 ¹¹ Hz), since the absence of moving mechanisms guarantees the absence of intrinsic mechanical resonances that deform the transfer function.

When the voltage decreases, under the influence of which the formation of kinetic tunnels occurs, the molecules of the working fluid infiltrate from the environment back into the body of the dielectric membrane. At the same time, significant changes in the temperature of the converter itself and the environment are not observed.

This phenomenon can be observed visually using photo or video equipment that allows recording thermal radiation. As mentioned above, the coefficient of increase in the speed of a molecule depends on the number of degrees of freedom of molecules (n), determined by the structure of the substance, and is equal to √n.

A hydroacoustic transducer operating in seawater must consider that the presence of salinity makes it a weak electrolyte. Therefore, in order for the electrolyte ions not to terminate on the radiator plates, both of its electrodes must be covered with an insulator. As for atmospheric emitters, it is expedient to use weakly hygroscopic materials as a dielectric membrane, the selection of which is the subject of this study.

The manufactured laboratory models allowed to obtain an audio signal level of up to 130 dB. Theoretically, this method of producing acoustic vibrations does not impose restrictions on the frequency range of the emitter, since the working medium is the molecules of the medium, and its frequency limits are determined only by the size of the particles and the level of the sound signal, and the dynamic range of the emitting system is determined only by the mechanical strength of the emitter membrane itself. The maximum efficiency of a converter working with air can reach 80% (of the kinetic energy of the air stored in the radiator membrane and used as a working medium), which is significantly more than the energy expended by the radiator for its operation.

3.2.2 Saturated steam generator

The lack of humidity in the natural environment of the UAE indicates the need for engineering solutions to artificially saturate the atmosphere with moisture. As you know, air humidity rises as a result of evaporation. The lack of freshwater makes it expedient to use seawater for artificial evaporation.

In hermetic or quasi-hermetic conditions, saturated steam tends to achieve thermodynamic equilibrium between gas and liquid. It can be displaced by pumping air under pressure above the surface of the water in the evaporator, heated above the boiling point. The minimum conditions for the formation of supersaturated steam are: temperature 125⁰С and pressure 2.37 kg/cm². Higher temperatures require the use of more temperature-resistant materials; increasing the pressure above the surface of the evaporator also requires additional design solutions.

The evaporator of flowing seawater must saturate the ascending vortex with moisture. According to calculations, at an upward flow rate of 20–25 m/s with a diameter in the narrow part of the tower of 30 m and an ambient temperature of 22°С, the moisture flow can reach 1350 mm/h, that is, 0.38 kg/(s*m²), that is, the unit will be able to generate an upward flow of water with a volume of 267 kg/s.

Each water molecule can simultaneously form four hydrogen bonds with other molecules at strictly defined angles equal to 109°28′. They are directed to the vertices of the tetrahedron as shown in Figure 10 [15].

Figure 10.

Structure of the water molecule [14].

Water molecules have a large dipole moment, which leads to the fact that they interact with each other in the liquid state, forming connected structures. Numerous short-lived hydrogen bonds between neighboring hydrogen and oxygen atoms in a water molecule create favorable opportunities for the formation of special structures—clusters of hydroxyl clouds, formed around impurity ions.

According to the hypothesis of S.V. Zenin [14], water is a hierarchy of regular bulk structures, which are based on a crystal-like “quantum of water,” consisting of 57 of its molecules, which interact with each other due to free hydrogen bonds. At the same time, 57 water molecules (quanta) form a structure resembling a tetrahedron. The tetrahedron, in turn, consists of 4 dodecahedrons (regular 12-sided). 16 quanta form a structural element consisting of 912 water molecules.

If molecules of another substance, for example, ions of anions or cations, are placed in water, the clusters will begin to “take over” its electromagnetic properties. This property explains the extremely labile, mobile nature of their interaction. Its nature is due to long-range Coulomb forces, which determine a new type of charge-complementary bond.

It is due to this type of interaction that the construction of structural elements of water into cells up to 0.5–1 micron in size is carried out. They can be directly observed with a phase contrast microscope. Water, consisting of many clusters of various types, forms a hierarchical spatial liquid crystal structure.

Water clusters at the phase boundaries (liquid–air) line up in a certain order, while all clusters oscillate with the same frequency, acquiring one common frequency. The oscillation frequency of water clusters can be determined by the following formula:

$$w=\sqrt{\frac{\alpha }{M}}=2\mathit{\pi f},$$E3

where α is the surface tension of water at a given temperature; M is the mass of the cluster.

The oscillation frequency of the cluster f at room temperature 18°C is equal to f = 6.79 10⁹ Hz. To experimentally test the presence of such oscillations of water clusters, the researchers detected water radiation using biological objects—wheat seeds.

The self-organized system of water, when exposed to electromagnetic radiation, will not move as a whole, but each element of the hexagonal structure, and in the case of impurities and of another type in the area of their location, will be displaced; that is, there will be a distortion of the geometry of the structure and, consequently, stresses will arise.

The energy of electromagnetic radiation quanta, passing into the internal energy of a structured water medium as a result of its distortions, will be accumulated by it until it reaches the hydrogen bond energy. When this value is reached, the hydrogen bond is broken and the cluster structure is destroyed. This can be compared to a snow avalanche, when there is a gradual, slow accumulation of mass, and then a rapid collapse.

The energy costs for bringing water to the boiling point and the phase transition of individual water molecules from a liquid state to vapor are very high [16]. To increase the volume of evaporation, it is not necessary to heat the entire volume of water in the evaporator. It is sufficient to use resonant high-frequency acoustic emitters capable of achieving mechanical resonance of the cluster structure of sea water (Figure 11), since resonant vibrations can destroy hydrogen bonds between cluster molecules and give them the necessary kinetic energy.

Figure 11.

Vertical cross section of the evaporator with a comb of high-frequency acoustic emitters.

The destruction of hydrogen bonds in hydroxide clouds surrounding sea salt ions leads to the appearance in the volume of seawater of a large number of unbound water molecules, the kinetic energy of which is sufficient to overcome the forces of surface tension.

If an imbalance is provided in such an evaporator between superheated air and seawater entering it, then the thermodynamic equilibrium will shift to the area of superheated steam.

3.2.3 Solar collector

The task of the solar collector is to create a temperature gradient between the base and the upper section of the “Rain Tower,”, which forms a vertical thrust of the upward flow. For this purpose, the greenhouse effect is used, which is achieved due to the transparent coating of air intakes [12, 13].

The supersaturated steam generator has a distributed infrastructure, since air saturation with moisture is necessary in all air ducts of the solar collector at the same time. Supersaturated steam from the steam generator enters each duct sleeve of the solar collector. Its pressure drops, and it cools down, mixing with the surrounding air.

With the natural supply of steam, condensation occurs in full dependence on temperature, atmospheric pressure in the solar collector. The output of steam under pressure from the steam generator forms its directional movement, as a result of which less thermal energy is required, and condensation of cloud droplets occurs faster (Figure 12).

Figure 12.

Multi-start spiral in solar collector topology.

The solar collector architecturally performs the role of a greenhouse with a transparent roof for heating the air due to solar radiation and the formation of an elevated temperature at the base of the tower. The temperature gradient creates vertical thrust. The guides in the topology of the solar collector form a vortex structure (Figure 12), and the vertical angle of elevation of the air ducts sets the step of the rotational and translational motion of the updraft.

The solar collector architecturally plays the role of a greenhouse with a transparent roof for heating the air due to solar radiation and forming an elevated temperature at the base of the tower. The temperature gradient creates vertical thrust. The guides in the topology of the solar collector form a vortex structure, and the vertical angle of the air ducts sets the step of the rotational–translational movement of the upward flow.

Optimization of the solar collector topology during digital modeling of the operation of the air intake of the Rain Tower digital twin will determine the required number of air ducts and the most efficient form of spiral turns, guaranteeing the maximum throughput of the solar collector and the maximum updraft speed.

3.2.4 Aero-thermal power plant

The thermal gradient that occurs in the Rain Tower due to the solar collector forms a fast-upward swirl of air. The hyperbolic generatrix of the tower surface focuses the flow into the narrow part of the tower, which acts as an impeller attachment to the turbine, which converts the kinetic energy of the upward flow into mechanical rotation.

The aero-thermal power plant in the “Rain Tower” is easy to operate, since the rotation of the rotor in such a design is the most uniform, and the speed of the ascending vortex flow fluctuates slightly due to control actions that adapt the turbine operation mode to changes in environmental parameters.

The turbine rotation speed reported to the rotor and its spatial layout significantly affect the design features of the generator. A wind turbine with a vertical layout does not require forced mechanisms to start, since the rotor movement begins when the airflow reaches the minimum pressure values, due to the minimization of reactive losses.

This is achieved due to the optimal shape of the turbine blades of the impeller of the aero-thermal power plant, which coincides with the shape of the forming tubes of the upward vortex flow velocity, which significantly reduces the dynamic loads on the support units and thereby increases their service life.

Low-speed power generators usually use permanent neodymium magnets (Nd-Fe-B) in their rotor, which can be made in different shapes and sizes. Their operating temperature range is −60⁰ … + 120⁰С, and the service life is more than 10 years. The main parameters of neodymium magnets are given in Table 1.

Residual magnetic induction, Br	1.36–1.42 T
Coercive force by magnetization, Hcb	>907 kA/m
Coercive force by induction, Hcj	>1353 kA/m
Maximum magnetic energy, BH	358–382 kJ/m^3

Table 1.

Physical parameters of permanent neodymium magnets.

Stator inductors are usually made of copper tape, which has high conductivity and low losses and gives a compact design. The design of the aero-thermal power plant is characterized by a simple control system and low operating costs, which makes it attractive. Unlike wind turbines with an open turbine, the design does not create dangerous and destructive vibrations. The “Rain Tower” with a built-in aero-thermal power plant on an ascending vortex flow in a closed duct works in any climatic conditions and can withstand strong gusts of wind, up to hurricane values, since its seismic resistance reaches 9 points on the Richter scale.

From an environmental point of view, an aero-thermal power plant with a vertical generator arrangement is not dangerous for birds due to the fact that it is perceived by them as a single obstacle that must be bypassed. It has a low sound background. Unlike horizontal structures, the level of acoustic pollution rarely exceeds the threshold of 18–20 dB. In addition, there are no frequencies close to the lower threshold of hearing, the so-called infrasound, which adversely affects human health. The generation of electromagnetic radiation by a generator with a vertical axis of the rotor is minimal and is not felt by others.

Not an unimportant role in achieving maximum efficiency. Aero-thermal power plant is played by the constancy of the parameters of the ascending vortex flow, which, in the absence of control actions, significantly depend on the environmental parameters (temperature, pressure, humidity, etc.).

3.2.5 Vortex and coagulation control system

In the “Rain Tower,” the process of coagulation of cloud droplets into raindrops occurs as they drift in an ascending vortex flow. Cloud droplets in the process of rotational–translational motion collide and stick together into larger raindrops. At the same time, an increase in the volume and mass of droplets leads to the appearance of their radial drift to the center of rotation according to the law of conservation of momentum of the amount of motion.

To transfer large droplets to a higher orbit, they need to be given an additional linear velocity. While maintaining the angular velocity, the centrifugal acceleration imparted to the drop will ensure its drift along the radius of rotation in the vortex and transfer it to a higher orbit.

An electrically neutral drop can be linearly accelerated by acoustic pulses. In this case, due to the asymmetry of pressures on the surface of the drop, which occurs at the leading edge of the oncoming pulse, it is picked up and accelerated, like a surfer on the slope of a sea wave.

Acoustic pulse transmitters can be placed on the inside of the “Rain Tower” wall above the generator turbine. The axial symmetry of the directional patterns of the acoustic emitters of the control system during their in-phase operation leads to a centripetal drift of all droplets to the axis of rotation.

However, the use of phase delays between the individual elements of the radiating module makes it possible to electronically control the deflection of the beam of the radiation pattern, directing its axis not along the diameter, but along the chord of a circular section. In addition, it is possible to control the angle of inclination of the main beam of the radiation pattern of the radiating module not only horizontally but also vertically. Thus, the minimum number of elements in such a control module must be at least four.

The rotational–translational motion of drops in a vortex flow requires continuous correction of their trajectory so that the total vector of their velocity rotates along with the vortex. By placing the radiating modules of the control system with an angular displacement along the inner surface of the body of rotation, it is possible to create a traveling wave of the control action, which will be transmitted from module to module with a phase delay corresponding to the angle of rotation of the vortex body.

The controlling effect on the coagulating droplets will depend on the spectrum of their sizes, since with the equality of the impact force on the droplets, the difference in their masses will lead to sorting them according to the accelerations and velocities given, depending on the amplitude, duration and shape of the emitted pulses, as well as the frequency of their repetition.

Thus, by varying the parameters of the control actions, it is possible to set the distribution of water droplets by size, velocities, and location in the orbit of rotation, as well as by controlling the step of the rotational–translational movement of the ascending vortex flow, taking into account its dependence on environmental parameters at different horizons of the undisturbed atmosphere, to set the path that each drop of water will travel as it moves inside the tower and guarantee the distribution of raindrops in size and velocities on the upper section of the tower.

The system of sensors located on the inner surface of the “Rain Tower” will allow you to control the dynamic state of the ascending vortex flow throughout the entire interior of the tower. This multiparameter monitoring system will allow you to quickly classify the state of the “Rain Tower” considering the current environmental parameters and develop the most optimal control pattern of distributed impact on the ascending vortex flow [17, 18, 19, 20, 21, 22].

3.2.6 Concentration and dissipation of vortex flow energy in the atmosphere

The control system for matching the vortex flow with the atmosphere and controlling the coagulation of raindrops is based on the idea of forming a virtual air duct, which is formed due to the use of an annular pulsed acoustic emitter on the upper section of the Rain Tower.

Concentric impulse waves emitted one after the other form a virtual duct. Hypersonic concentric pulses form a cylindrical body of revolution, composed of areas of high pressure, propagating at supersonic speed.

As shock waves dampen as a result of collisions, that is, friction that occurs when mass is transferred at supersonic speed, they turn into ordinary sound waves spreading in space like circles on water or rings of smoke. In this case, a divergent cone of a virtual air duct is formed, the walls of which, when damped, smooth out the pressure contrast at the boundary between the vortex and the undisturbed atmosphere.

The location of several “Rain Towers” along an imaginary perimeter allows you to create a more powerful total central vortex, capable of moving large air masses saturated with moisture. When forming a total vortex, it is necessary to consider the patterns of its formation, since such a nature-like technology, with its uncontrolled use, can potentially give rise to an uncontrolled natural disaster [23].

According to Professor Yakovlev of the Urals University, Professor Mayer of Harvard University managed to find a unique way to simulate the interaction of linear vortices of the same intensity with the same direction of rotation (same polarity) [24].

Mayer used equally magnetized needles stuck in small corks floating in a vessel of water. Needle magnets were positioned so that all of their positive poles were above the water. Such positive poles are attracted to an electromagnet placed above the vessel and simultaneously repel each other with forces inversely proportional to the square of the distance between them. A regularity was found, which showed that the most stable are symmetrical configurations of magnets located on concentric circles.

William Thomson Kelvin discovered the analogy of the stationary position of magnets with a system of point vortices of the same intensity located around the center of symmetry, and J. J. Thomson mathematically proved that a regular vortex N-gon does indeed form a uniform rotation around the center of symmetry (Figure 13) [25].

Figure 13.

5 degrees of strengthening the stabilization and power of the central vortex by increasing the number of linear vortices in the rain towers.

Based on the analysis of the solution in a linear approximation, he showed that for small fluctuations in such a vortex structure, the most stable are polygons with the number of vortices N < 7 as show at Figure 13. That is, to ensure stable rotation of the air mass in the center of the polygon of the “Rain Towers” located along the perimeter, six towers will create the most stable central vortex due to rarefaction in the center of symmetry that occurs when the vortices are added. At present, we continue to search for new static configurations of vortices using numerical methods.

In the case of interaction of linear vortices with the same direction of rotation, there is no balance of forces. There are only repulsive forces imperceptible at distances greater than three vortex diameters and rapidly increasing at distances less than two vortex diameters. Therefore, regular polygons cannot formally be static configurations. Over time, the circle along which the polygonal configuration rotates around the center of symmetry should increase in size.

Attention should be paid to the feasibility of the model under consideration, which was confirmed on Saturn. A stable vortex in its atmosphere, discovered by NASA, has existed for many years (Figure 14).

Figure 14.

Interaction of vortices on Saturn, © NASA/JPL-Caltech/Space Science Institute/Rakesh K. Yadav via Eurekalert!

It is stimulated by smaller vortices, which, despite their fluctuations, form a hexagonal structure (Figure 15).

Figure 15.

Cassini filmed a hexagonal storm on Saturn, © NASA/JPL-Caltech/SSI/Hampton University.

Formally, regular polygons will be more static if a linear vortex with the opposite direction of rotation is placed in the center of symmetry. In this case, due to attraction to the central vortex, the distances between unipolar vortices are smaller. Attractive forces arise between oppositely directed vortices according to Bernoulli’s law. There is a common flow between them, therefore reduced pressure.

The normal external pressure of the medium presses the vortices of different polarity to each other. Between unipolar vortices, the flows are directed toward each other; therefore, an increased pressure arises in the space between them, which creates repulsive forces. If both repulsive and attractive forces exist simultaneously, then there must be a balance between them. With the balance of forces, the distance between the vortices can no longer change; now the configurations will indeed be static.

It was shown that all asymmetric vortex configurations are unstable to initial perturbations. And for symmetrical vortex configurations, it was shown that a system of N identical point vortices located at the vertices of a regular polygon rotates with a constant angular velocity at an arbitrary value of the intensity of a point vortex located in the center of the polygon, and therefore, when the “Rain Towers” are located with unipolar vortices rotating in one direction, symmetrically around the circle, they can generate a stable central vortex with rotation in the opposite direction, having several times greater power and therefore having the ability to carry a large mass of saturated air up to form a thundercloud.

4. Conclusion

The problem of irrigation of arid lands by rainfall is acute in different parts of the globe: in the Middle East, China, Africa, and South America. According to World Scientists’ Warning to Humanity, the shortage of freshwater per capita on the planet is continuously growing [26]. The solution of this problem by means of environmentally responsible anthropogenic impacts becomes especially demanding in the conditions of planetary warming and disturbance of the ecological balance in the territories of risky agriculture.

The proposed solution is a continuous industrial production, the management of which allows you to control the level of anthropogenic impact on arid areas, considering possible changes in local climatic conditions.

Continuous accumulation of statistical data and replenishment of the sample of the multiparametric vector of the state of an open physical system formed by a complex of one or more Rain Towers will ensure flexible adaptation of the control system with Artificial Intelligence for the formation of thunderclouds to the continuously changing climatic situation on the planet.

The Rain Tower is an industry 4.0 solution with autonomous power supply. At the same time, the aerothermal power plant built into the tower is the most energy-efficient and compact solution in the wind power industry. It is characterized by a low level of noise pollution, has no carbon footprint, and allows desalination of seawater, which is unsuitable for irrigation and agricultural tasks.

In addition to the Rain Tower, such a solution to create an aero-thermal power plant built into the building allows the volumes of electricity generated to be directed to the needs of related infrastructure: residential complexes, sewage treatment plants, or other industrial enterprises of urban infrastructure.

The Rain Tower integrates several inventions and know-how into a single balanced engineering and technical solution, ensuring the interaction of heterogeneous physical processes that guarantee the management of moisture content at specified atmospheric horizons, considering the wind rise and other climatic parameters that affect the formation of thunderclouds.