Active and passive collaborative heat storage wall heating system for solar greenhouse

Abstract

The invention discloses an active-passive cooperative heat storage wall heating system of a solar greenhouse, and belongs to the technical field of agricultural facilities. The active-passive cooperative heat storage wall heating system mainly comprises a phase-change heat storage wall, a concentration-type solar air heat collector system, an active heat storage heating system body and an equipment control unit. The phase-change heat storage wall is composed of a cement mortar layer, a phase-change heat storage layer, a bearing building block layer and a thermal insulation layer from the indoor side to the outdoor side, wherein the phase-change heat storage layer is formed by pouring phase-change materials packaged through steel drums, heat storage coil pipes, gravel and cement. The solar air heat collector system is formed by connecting multiple groups of condensation-type solar air heat collectors in series, and a sunshade device used in summer is arranged above the heat collectors. The active heat storage heating system body is composed of a heat collector, thermal insulation pipes, a heat storage coil pipe, a frequency conversion fan, air openings and air valves. The equipment control unit is composed of a controller, a temperature sensor and electric adjusting air valves. According to the active-passive cooperative heat storage wall heating system, active and passive heat collection, heat storage and heat supply of the wall of the solar greenhouse are combined, therefore, the heat storage and thermal insulation performance of the wall of the solar greenhouse can be obviously enhanced, the solar energy utilization rate of the greenhouse can be obviously increased, and the adjusting capacity of the heat storage wall of the solar greenhouse to the heat environment in the greenhouse is improved.

Description

technical field [0001] The invention relates to a solar greenhouse active-passive collaborative heat-storage wall heating system integrating active and passive heat collection, heat storage and heat supply, which uses a concentrating solar air heat collection system and a phase-change heat storage wall. , belongs to the technical field of agricultural facilities. Background technique [0002] In most parts of northern my country, the outdoor temperature is usually below 0°C in winter, but solar energy resources are abundant. The off-season growth of crops can be realized by using the solar greenhouse. The traditional solar greenhouse relies on the radiation of sunlight to increase the air temperature in the greenhouse during the day, and uses the greenhouse wall to store passive sensible heat. temperature required for growth. However, this kind of greenhouse has the following problems: First, because the solar energy transmitted through the front roof of the solar greenho...

AI Technical Summary

Problems solved by technology

However, this kind of greenhouse has the following problems: First, because the solar energy transmitted through the front roof of the solar greenhouse to the inner surface of the north wall of the greenhouse affects the heat storage of the wall. The heat supply capacity is small, so that the utilization rate of solar energy in the greenhouse is low; the second is that due to the thermal inertia of the thermal storage wall material, the heat stored in the wall cannot be released in time only by passive heat dissipation of the wall, resulting in The environment in the solar greenhouse in winter is generally low temperature and high humidity, resulting in frequent crop chilling damage and freezing damage, and low crop yield; third, the use of heating measures consumes a lot of conventional energy, causing environmental pollution and high operating costs

[0004] Although the current research has improved the thermal environment of the solar greenhouse to a certain extent, there are still many defects that need to be further improved.

In particular, for the greenhouse wall, only focus on heat storage, while ignoring the influence of the thermal inertia of the wall material on the heat release lag of the wall. low function

During the use of the organic composite shape-setting phase-change material board in the greenhouse, the aging of the packaging material leads to the leakage of the phase-change material, resulting in a short service life of the material, pollution of the planting environment, and the fire resistance of the organic material cannot meet the requirements of use.

In the process of active heat storage, the air passages of the wall composed of hollow brick holes are poorly sealed, and the inward air leakage into the greenhouse is serious during heat storage, which significantly reduces the energy efficiency of active heat storage

In addition, the carrier of active heat storage uses water as the medium, and the problem of antifreezing at night in cold winter has not been well solved

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