RU2193147C1 - Solar air-and-water heater - Google Patents

Abstract

FIELD: plants for heating air and water by solar energy where provision is made for change-over from one heat exchanger to another. SUBSTANCE: air or water flows through sinusoidal tube laid on surface of heat accumulator and partially sunken in sand layer of heater accumulator. Accumulator consists of two layers: gravel layer and sand layer. Window glass sealed-up in metal framework is used as translucent coat for air-and-water heater. EFFECT: simplified construction; reduced labor consumption; low cost. 1 dwg

Description

 The invention relates to the field of agriculture, and more specifically to air-heating installations, and can be used in the field of crop production of protected soil, especially in high altitude conditions.

 A known design of the solar collector-accumulator, comprising a heat-insulated casing with a heat-absorbing panel mounted obliquely, forming the front wall of the tank for the coolant, and a partition installed in the tank, located along the heat-absorbing panel, the partition is made with transverse holes [1].

 The disadvantages of this solar collector are the complexity of the design and its purpose only for heating water.

 A solar installation is also known, which contains a multi-stage solar collector, a cold water supply tank with a float water level regulator, and a battery tank located below the cold water supply tank, and a control valve and a temperature controller are located on the last step of the solar collector [2].

 The disadvantages of this design are installation complexity and a narrow area - only for heating water.

 Of the known solar air heaters, the closest in technical essence is the "solar air heater" [3].

 It describes a dual-purpose collector - a solar water heater. Its constructive solution and principle of operation are as follows. A tubular boiler is placed on a perforated metal sheet-adsorber of solar energy. Water is supplied to the solar water air heater from below and through a thermosiphon circulation enters the storage tank. The air flow, either counterflow or cross, passing through the perforated sheets, removes heat from the heat-receiving surfaces of both the adsorber and the tubular boiler. This allows the use of a solar water heater in combined solar installations.

 A design disadvantage of the described solar water air heater is that it is structurally difficult to execute, the use of a water heater at the same time two heat carriers (water and air) reduces its effectiveness both for heating water and for heating air. Another disadvantage of this design is that it does not provide for the natural circulation of cold and heated air - the air inlet and outlet are located at the same level.

 The objective of the invention is to increase the efficiency of the air heater, simplifying the design of the installation, reducing the complexity of installation, reducing construction costs.

The essence of the invention is that in the solar air heater the heat accumulator is made of two layers, the lower layer being gravel and the upper sand one, in which the heat pipe is partially recessed, and at the pipe inlet there is a tap for switching the heat carrier, while the air heater is placed at an angle of 30-60 ^o depending on the latitude of the area.

 The solar air heater provides for the passage of various coolants (water, air) along the same path. The heat accumulator is located in such a way that it simultaneously acts as a heat insulator of the air heater. The heat pipe is made of a pipe bent in a sinusoidal shape, and is partially buried in the sand layer of the heat accumulator.

 The main purpose of dual-purpose solar heaters is the heat supply of solar heaters, especially in high mountains, where the temperature of irrigation water is very low even in summer, and the fluctuations in day and night temperatures are high. The design of the solar air heater provides the ability to switch from one coolant-air, to another - water, along the same path, for this a dual-purpose collector is used.

 In FIG. 1 shows a general view of a solar air heater, which consists of a metal frame - 1, laid along the perimeter and divided in the middle, a gravel layer - 2, a sand layer - 3, a metal pipe for a coolant - 4, an entrance - 5 and an exit - 6, a glass coating - 7, crane switch - 8.

Solar air heater is placed at an angle of 30-60 ^o to the horizon, depending on the latitude of the area. This increases the efficiency of using solar energy and, if an air heater is used to heat water, cold water is supplied from below. Having a difference in height, water rises through the pipe and heats up, then it is used to water plants in the greenhouse. If the air heater is used to heat the air leading into the greenhouse, then the lower end of the pipe leaves open and the air heated in the air heater creates traction and, rising through the pipe, provides the greenhouse with warm air.

 In this design, sand and gravel play the role of the battery and the heat insulator of the installation. The incoming solar radiation, passing through a transparent glass coating, heats both the pipe and the battery at the same time. The pipe for the coolant may be whole or assembled from separate parts of the pipe, interconnected by an elastic rubber or other pipe, located as shown in figure 1.

Testing of the installation showed that with this design of a solar air heater, it is possible to obtain water heated to 30-50 ^° C and air heated to 40-50 ^° C and provide heat without attracting electrical or other energy.

 Thus, the proposed design does not require special manufacturing costs, is easily accessible, convenient to use and can be used in any location.

LITERATURE
1. Application for invention 95118685/06. F 24 J 2/04, bull. 26, 1997

 2. Copyright sv. 2124680, F 24 J 2/04, bull. 1, 1999

 3. Information leaflet of the Scientific Research Institute of Scientific and Technical Research and the Turkmen Technical University, series: solar technology 108-88, "Solar air heaters for heat supply systems."

Claims (1)

A solar air heater including a dual-purpose collector, a translucent coating, a coolant in the form of water and air, a heat accumulator, characterized in that the heat accumulator in the solar air heater is two-layer, the lower layer being gravel and the upper sand one, the heat pipe is made sinusoidal and partially recessed a sand layer heat accumulator pipe installed at the entrance region for switching the coolant, wherein vozduhovodonagrevatel disposed at an angle 30-60 ^o depending on the latitude.