RU155180U1 - CONSTRUCTION FOR THERMOSTATING SOILS UNDER BUILDINGS AND CONSTRUCTIONS - Google Patents

Abstract

1. Design for thermostating of soils under buildings and structures, having a first cooling circuit that contains gravitational heat pipes, the horizontal evaporation sections of which are located below the ground level under the building or structure to be cooled, connected via transport zones with vertical condenser sections located above the ground characterized in that it is additionally equipped with a second cooling circuit, made in the form of vertical gravitational heat pipes, cond the condensation sections of which are in thermal contact with the horizontal evaporative sections of the gravity pipes of the first circuit, all the evaporative sections of the heat pipes are provided with an internal capillary-porous coating, and shut-off valves are installed in the communication lines of the condenser sections of the heat pipes of the first circuit located above the ground level with the evaporative sections designed to shut off the system as necessary, thermal contact between the condenser sections of the heat pipes of the second circuit and the evaporating sections of the heat pipes of the first circuit are carried out by means of a profile made of a material with high thermal conductivity. 2. The construction according to claim 1, characterized in that the capacitor sections of the primary circuit are arranged vertically and are combined in a bundle located on the construction service site. The construction according to claim 1, characterized in that it is equipped with a heat pump, the evaporation section of which is in thermal contact with the pipes of the transport zones of the primary circuit. The construction according to claim 1, �

Description

Design for thermostating of soils under buildings and structures.

The proposed utility model relates to the field of construction, namely, devices for cooling and freezing soils and can be used in the construction of structures in areas of permafrost distribution in order to increase the bearing capacity of soils of foundations and foundations as a result of their temperature control at low temperatures.

Features of the foundations of structures erected on permafrost soils are determined by specific climatic conditions in high-latitude regions of the Far North. In winter, the air temperature there is quite low for a long time and often reaches minus 40 °. However, snow cover and low thermal conductivity of the soil do not allow it to freeze deeply and severely. In the summer season, frozen ground thaws, in addition, when deviating from the design mode of operation of heated buildings and structures, the process of thawing of frozen soils is more intense, and this creates the threat of deformation of the foundations and destruction of buildings and structures.

One of the ways to preserve the negative temperature of frozen bases under structures is the use of artificial freezing of thawed melt or cooling of frozen soils of foundations with the help of cooling units with mainly seasonal effects. Seasonally-active cooling devices in winter additionally cool frozen soil, and in summer they do not work. The use of such devices can significantly increase the bearing capacity of the foundations of structures and prevent the development of deformations of the bases in the summer.

Known cooling device for freezing soil (RU 120974 U1, IPC E02D 3/115, published 04/26/2012), containing horizontally parallel to each other cooling pipes filled with low-boiling liquid, heat-insulating dust over the cooling pipes and condenser heat exchangers, while the ends of the cooling the pipes are bent upward at 90 ° and protrude 1-2 m above the insulating bed with an individual condenser heat exchanger at the end of each cooling pipe, the lengths of the cooling pipes correspond to the length of the conveyor container, and if the configuration of the cooled foundation of the structure exceeds the length of the transport container, the length of the cooling pipes is increased by connecting their ends on a heat-conducting paste inside the docking housings.

A disadvantage of the known design is low maintainability, which leads to the need for redundancy of additional cooling pipes under the dumping, and this in turn reduces the reliability of the device.

Closest to the proposed is a temperature stabilization system for soils of the foundations of buildings and structures (RU 141110 U1, IPC E02D 3/115, published May 27, 2014), which has a cooling circuit that contains a system of gravitational heat pipes, the horizontal evaporative part of which is located below the ground level under the building or structure to be cooled, connected by means of transport zones to a vertical condenser part located above the ground level,

In this case, the evaporative parts of the heat pipes are located at the base of the structure with a slope of 10 ° to 0 ° to the longitudinal axis of the structure. According to the utility model, evaporation zones are located in the natural soil of the base, in through holes drilled by the directional drilling method, under the entire structure contour.

However, the known device does not have a high thermal efficiency, since it depends on the air temperature in the cold period, therefore, when high temperatures are set in the winter, the device does not turn on. Soil of the base is not frozen, and the thermal inertia of the ground of the soil frozen in winter may not be sufficient to maintain it in solid form during the summer period i.e. the task of temperature control of the soil at the level of negative temperatures may not be achieved.

The technical task of this utility model is to create a structure that has increased power characteristics compared to the prototype and enhanced operational capabilities.

The technical result is the creation of a structure for thermostating of soils under buildings and structures, which provides an increase in the bearing capacity of the soil of the base due to the maintenance of a given temperature regime, increasing the efficiency of the structure as a whole by applying capillary-porous coatings inside the evaporator pipes and increasing the heat exchange area of the evaporative part of the structure , improving the performance of the structure as a result of the ability to monitor the process is cooled I, maintenance and repair of cooling equipment, as well as the use of heat removal for practical purposes (for example, for heating buildings or hot water).

The solution of the technical problem and the achievement of the technical result are ensured by the fact that the structure for thermostating of soils under buildings and structures, having a first cooling circuit, which contains gravitational heat pipes, horizontal evaporation sections of which are located below the ground level under a cooled building or structure, are connected by means of transport zones with vertical condenser sections located above the ground, is additionally equipped with a second cooling to nturom designed as a vertical gravitational heat pipe condenser sections which are in thermal contact with horizontal evaporator sections gravitational first pipe circuit. All evaporation sections of the heat pipes are provided with an internal capillary-porous coating, and in the communication lines of the condenser sections of the heat pipes of the first circuit located above the soil level with the evaporation sections, shut-off valves are installed to shut down the structure as necessary, thermal contact between the condenser sections of the heat pipes additional secondary circuit and evaporation sections of the heat pipes of the primary circuit is carried out by means of a profile made of a material with a high thermal conductivity. The capacitor sections of the primary circuit are arranged vertically and are combined in a bundle located at the construction service site. The design can be equipped with a heat pump, the evaporation section of which is in thermal contact with the pipes of the transport zones of the primary circuit. Docking of transport, evaporation and condenser sections of heat pipes can be done through flexible connections.

The essence of the proposed utility model "Design for temperature stabilization of soils of the foundations of buildings and structures" is illustrated by the diagrams presented in the figures:

- in FIG. 1 shows a diagram of a vertical section of the proposed design for thermostating of soils under buildings and structures.

- in FIG. 2 shows a diagram of a vertical section of the proposed design for thermostating of soils under buildings and structures equipped with a heat pump.

The design for thermostating of soils under buildings and structures (Fig. 1) has a first cooling circuit in the form of gravitational heat pipes with condenser sections 1 located vertically above the ground. Condenser sections 1 by means of transport zones 2, united above the soil surface in a bundle, are connected with horizontal evaporation sections 3 located below the ground level under the building or structure. Each of the condenser sections 1 is connected to the communication line with the evaporation section through the valve 4. The evaporation sections 3 of the gravity pipe of the first circuit through a heat transfer element, for example, a metal profile 5, are in thermal contact with the horizontally directed condenser sections 6 of the gravity pipe of the second circuit having vertical evaporation sections 7.

To increase the efficiency of using low-grade heat, the design for temperature stabilization of the soil of the foundations of buildings and structures can be equipped with a heat pump (Fig. 2). The heat pump evaporator 8 is in thermal contact with the refrigerant vapor rising from the evaporative sections of the primary circuit 3 to condenser 1. Compressor unit 9 of the heat pump pumps hot compressed refrigerant vapors into the condenser section 10, which can be located under the floor 11 of the building or structure. It is also possible to use the heat removed from the condenser section of the heat pump to produce hot water. In addition, the condensation heat of the heat pump refrigerant can be used to heat the intermediate coolant.

The design operates as follows. In the course of construction work, first vertical and then horizontal gravity pipes of the first and second circuits are mounted.

Evaporative sections of heat pipes of the first cooling circuit are placed in the natural soil of the base inside the perimeter of the structure. The free ends of the evaporation zone of the primary circuit are taken outside the perimeter of the structure and connected to the transport zone, which is laid in trenches oriented along the longitudinal axis of the structure, and the free end of the transport zone is connected to condensation zones that are collected in a bundle. The condensation zones collected in the beam allow you to free the area around the structure, which greatly facilitates the maintenance of cooling devices, repair or replacement. In addition, each bundle of condensers is mounted on a supporting structure mounted on piles, equipped with a platform for refueling cooling devices, servicing and monitoring the cooling process. Transport zones can have flexible inserts, which allows you to change the angle of rotation when laying them in trenches.

The condenser sections 1 of the gravitational heat pipes are delivered to the installation site in the form assembled and charged with the refrigerant, with shutoff valves 4. The amount of refrigerant charged into the condenser sections corresponds to the norm that is necessary for the operation of each of the gravity heat pipes of the primary circuit. Next, the crimping and evacuation of the pipes of the transport and evaporation sections of the gravity pipes of the primary circuit are performed. After this, valve 4 is opened and the entire volume of each of the gravity heat pipes of the primary circuit is filled with refrigerant. Such a procedure compared with the prototype can significantly simplify the commissioning of the primary circuit since there is no need to charge refrigerant heat pipes on site in harsh climates. All necessary refrigerant is charged into the condenser sections at the factory during their manufacture. Sections are delivered to the place of operation separately, which also simplifies the transportation of structural elements to the place of their installation.

The evaporation sections of the heat pipes of the devices are mounted from pipes with an internal capillary-porous coating. In the experimentally studied evaporator tubes with a capillary-porous coating inside the evaporator tube, the freon is fairly evenly distributed along the contour, providing a relatively uniform heat transfer medium to the soil with a decrease in the negative temperature drop on the surface of the pipe in contact with the frozen soil to 1-2 ° C, i.e. . 6-9 times better than in a smooth pipe. This allows a simultaneous decrease in the negative temperature on the surface of the evaporator (on average by 5-6 ° C or more) to significantly accelerate the process of freezing the soil and closing the “ice-soil cylinders” that are close in shape to round-cylindrical, which makes the thermal engineering forecasts of thermal stabilization of the soil of the foundations of buildings and structures more correct, reliable and reliable. The use of evaporator tubes of vapor-liquid thermostabilizers with a capillary-porous coating made it possible, as a first approximation, to obtain an efficiency coefficient K = 3.4. This means that the internal thermal resistance of a structure with an evaporator from pipes with a capillary-porous coating is 3.4 times less than from pipes with a smooth surface. Accordingly, with the same temperature difference Δ, it is possible to transfer 3 times more thermal energy to the condenser and evaporator than when using the old design. The life of the thermostabilizer in the cold period also increases, which increases the volume of the ice-ground massif.

The construction for temperature stabilization starts up when the temperature of the air decreases relative to the soil temperature by 6-8 ° C. In this case, a pressure differential occurs between the evaporation sections 3 and the condenser sections 1 of the heat pipes of the first circuit, as a result of which the liquid refrigerant located in the evaporation section 3 boils (the process is accompanied by an endothermic reaction). Saturated refrigerant vapors flow into the air condenser section 1, where they condense on its inner surface. Further, the condensed refrigerant takes a temperature close to the temperature of atmospheric air and, under the influence of gravity, is lowered back to the evaporator 3. Once in the evaporation section 3, the liquid refrigerant heats up and boils (the process is accompanied by an endothermic reaction) due to the difference in its own temperature and the temperature of the walls of the evaporation section 3, goes into a vapor state and rises in the condenser section 1.

When cooling the evaporation section 3 through a metal heat-conducting profile 5, for example aluminum, the condenser sections 6 of the vertical gravity pipes of the second circuit are cooled. In this case, a pressure differential occurs between the evaporation section 7 and the condenser section 6, as a result of which the liquid refrigerant located in the evaporator 7 boils (the process is accompanied by an endothermic reaction). Saturated refrigerant vapors flow into the condenser 6, where they condense on its inner surface. Further, the condensed refrigerant takes a temperature close to the temperature of the freon inside the evaporation section 3 of each of the heat pipes of the first circuit and, under the action of gravity, rushes back to the evaporation section 7. Once in the named section 7, the liquid refrigerant heats up and boils (process accompanied by an endothermic reaction) as a result of the difference between the intrinsic temperature and the temperature of the walls of the evaporation section 7, it passes into a vapor state and rushes into condensation hydrochloric section 6.

For the operation of the structure throughout the year, as well as the use of the allocated low potential heat of the soil for practical (economic) purposes, a heat pump can be connected to the structure.

When the heat pump is turned on, its evaporator 8, located in the transport section 2 of the pipes of the primary circuit, receives a cooled working fluid, such as freon. Freon in evaporator 8 boils and evaporates at low temperature, absorbing heat taken from the environment by horizontal and vertical gravity tubes. Vapors enter the compressor, where their pressure and temperature rise. The compressed freon vapor enters the condenser 10, where the freon is cooled, transferring its latent phase transition heat to the coolant circulating in the heat supply structure. After cooling, the freon goes into a liquid state and returns to the evaporator 8 through the control valve (choke). Condensation heat transferred, for example, to the intermediate heat carrier can be used to heat the floor of the building 11 or to heat water in the hot water supply system.

The experiments showed that in the proposed design having evaporative sections of gravitational heat pipes capillary-porous coating inside the pipe, provides effective freezing and subsequent temperature control of the soil under the building or structure.

Claims (4)

1. Design for thermostating of soils under buildings and structures, having a first cooling circuit that contains gravitational heat pipes, the horizontal evaporation sections of which are located below the ground level under the building or structure to be cooled, connected via transport zones with vertical condenser sections located above the ground characterized in that it is additionally equipped with a second cooling circuit, made in the form of vertical gravitational heat pipes, cond the condensation sections of which are in thermal contact with the horizontal evaporative sections of the gravity pipes of the first circuit, all the evaporative sections of the heat pipes are provided with an internal capillary-porous coating, and shut-off valves are installed in the communication lines of the condenser sections of the heat pipes of the first circuit located above the ground level with the evaporative sections designed to shut off the system as necessary, thermal contact between the condenser sections of the heat pipes of the second circuit and the evaporating sections of the heat pipes of the first circuit is carried out by means of a profile of a material having high thermal conductivity. 2. The design according to p. 1, characterized in that the capacitor sections of the primary circuit are arranged vertically and are combined in a bundle located at the construction service site. 3. The design according to claim 1, characterized in that it is equipped with a heat pump, the evaporation section of which is in thermal contact with the pipes of the transport zones of the primary circuit. 4. The design according to p. 1, characterized in that the docking of the transport, evaporation and condenser sections of the heat pipes is carried out by means of a flexible connection.

Images