CN117870208A - Low-temperature type air source heat pump experiment system - Google Patents

Abstract

The invention discloses a low-temperature type air source heat pump experiment system, and relates to the technical field of air conditioner heat pumps. The invention comprises three subsystems, namely an air source heat pump system, a condensation temperature regulating system and an evaporation temperature regulating system. The invention is connected with the three subsystems through the condenser, the evaporator and the intermediate heat exchanger, the intermediate heat exchanger balances the cold and hot loads of the evaporation temperature regulating system and the condensation temperature regulating system, and a reasonable valve regulating scheme is adopted to provide the required low-temperature outside-greenhouse temperature working condition for the evaporator in the air source heat pump system and ensure the stability of the temperature of the cooling water entering the condenser, so that experimental research is not limited by outdoor weather conditions any more, the experimental cost is reduced, and the invention has the advantages of safety, convenience, high economy, good flexibility and the like.

Description

A low-temperature air source heat pump experimental system

Technical Field

The invention belongs to the field of air conditioning heat pumps, and in particular, relates to a low-temperature air source heat pump experimental system.

Background technique

Heat pumps consume a small amount of high-quality electricity or chemical energy of fuel to obtain a large amount of required heat energy. Their heating coefficient is always greater than one. Their development and promotion have important practical significance for alleviating energy shortages and reducing pollution emissions. So far, many scholars have studied air source heat pump heating systems from various aspects, but most of the research is only simulation analysis, lack of experimental research, and the operation of the system under a wide range of diverse actual working conditions and extremely cold conditions is still unknown. This is because the existing experimental system is greatly affected by environmental conditions, has high experimental costs, single research content, poor adjustment flexibility, and is difficult to operate under low temperature conditions.

Therefore, a low-temperature air source heat pump experimental system is proposed to solve the above-mentioned drawbacks.

Summary of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a low-temperature air source heat pump experimental system.

In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

A low-temperature air source heat pump experimental system includes three subsystems, namely an air source heat pump system, a condensing temperature adjustment system, and an evaporation temperature adjustment system;

The air source heat pump system comprises: a compressor, a condenser connected to the compressor, a drying filter connected to the condenser, a throttle valve connected to the drying filter, an evaporator connected to the throttle valve, and a gas-liquid separator connected to the evaporator;

The condensing temperature regulating system comprises: a cooling water outlet connected to the condenser, a cooling water inlet connected to the cooling water outlet, and a cooling water circulation pump connected to the cooling water inlet;

The evaporation temperature regulating system comprises: an expansion water tank, a stainless steel water pump connected to the expansion water tank, and an intermediate heat exchanger connected to the stainless steel water pump.

Optionally, in the condensing temperature control system, the cooling water circulating water pump inlet and outlet are equipped with a first bypass pipeline, the first bypass pipeline is equipped with a first regulating valve, the cooling water inlet is equipped with a second regulating valve, and the cooling water outlet is equipped with a seventh regulating valve; in the evaporating temperature control system, the evaporator inlet is equipped with a third regulating valve, the evaporator inlet and outlet are equipped with a second bypass pipeline, the second bypass pipeline is equipped with a fourth regulating valve, the intermediate heat exchanger inlet is equipped with a fifth regulating valve, the intermediate heat exchanger inlet and outlet are equipped with a third bypass pipeline, and the third bypass pipeline is equipped with a sixth regulating valve.

Optionally, the outlet of the cooling water circulation pump is connected to the inlet of the condenser, and the inlet of the cooling water circulation pump is connected to the outlet of the cooling water circulation pump via the first regulating valve to form the first bypass pipeline, the outlet of the condenser is connected to the inlet of the cooling water circulation pump via the cooling water outlet and the cooling water inlet, the cooling water inlet is connected to the second regulating valve, the cooling water outlet is connected to the inlet of the intermediate heat exchanger, the outlet of the intermediate heat exchanger is connected to the seventh regulating valve, the seventh regulating valve controls the condensing temperature of the condenser, the first regulating valve controls the cooling water flow rate of the condenser, and adjusting the first regulating valve and the seventh regulating valve at the same time can simulate the user's heating load.

Optionally, the outlet of the stainless steel water pump is connected to the inlet of the intermediate heat exchanger via the fifth regulating valve, the inlet of the fifth regulating valve is connected to the outlet of the intermediate heat exchanger via the sixth regulating valve to form the third bypass pipeline, the outlet of the intermediate heat exchanger is connected to the inlet of the evaporator via the third regulating valve, the inlet of the third regulating valve is connected to the outlet of the evaporator via the fourth regulating valve to form the second bypass pipeline, the outlet of the evaporator is connected to the inlet of the stainless steel water pump via the expansion water tank, the heat exchange medium in the evaporation temperature regulation system is ethylene glycol aqueous solution, the sixth regulating valve controls the evaporation temperature of the evaporator, the third regulating valve and the fourth regulating valve control the mass flow rate of the ethylene glycol aqueous solution entering the evaporator, the relative flow direction of the heat exchange medium in the intermediate heat exchanger is downstream, the fourth regulating valve controls the temperature of the ethylene glycol aqueous solution entering the intermediate heat exchanger, and the fifth regulating valve and the sixth regulating valve regulate the mass flow rate of the ethylene glycol aqueous solution entering the intermediate heat exchanger.

After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art. Of course, any product implementing the present invention does not necessarily need to achieve all the advantages described below at the same time:

The condenser, evaporator and intermediate heat exchanger connect three subsystems. The intermediate heat exchanger balances the cold and hot loads of the evaporation temperature regulation system and the condensation temperature regulation system. Through a reasonable valve adjustment scheme, the required low-temperature outdoor temperature working conditions are provided for the evaporator in the air source heat pump system, and the temperature of the cooling water entering the condenser is guaranteed to be stable, so that the experimental research is no longer restricted by outdoor meteorological conditions and the experimental cost is reduced. It has the advantages of safety, convenience, high economy and good flexibility.

The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described below are only some embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

FIG1 is a schematic structural diagram of a low-temperature air source heat pump experimental system according to an embodiment of the present invention.

In the accompanying drawings, the components represented by the reference numerals are listed as follows:

Compressor 1, condenser 2, drying filter 3, throttle valve 4, evaporator 5, gas-liquid separator 6, cooling water circulation pump 7, cooling water inlet 8, cooling water outlet 9, first regulating valve 10, second regulating valve 11, first bypass pipeline 12, expansion water tank 13, stainless steel water pump 14, intermediate heat exchanger 15, third regulating valve 16, fourth regulating valve 17, fifth regulating valve 18, sixth regulating valve 19, seventh regulating valve 20, second bypass pipeline 21, third bypass pipeline 22.

It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but rather to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments.

Implementation

The present invention will now be described in further detail with reference to the accompanying drawings.

Please refer to FIG. 1 , in this embodiment, a low-temperature air source heat pump experimental system is provided, which includes three subsystems, namely, an air source heat pump system, a condensing temperature adjustment system, and an evaporation temperature adjustment system;

The air source heat pump system includes: a compressor 1, a condenser 2 connected to the compressor 1, a drying filter 3 connected to the condenser 2, a throttle valve 4 connected to the drying filter 3, an evaporator 5 connected to the throttle valve 4, and a gas-liquid separator 6 connected to the evaporator 5;

The condensation temperature regulating system comprises: a cooling water outlet 9 connected to the condenser 2, a cooling water inlet 8 connected to the cooling water outlet 9, and a cooling water circulation pump 7 connected to the cooling water inlet 8;

The evaporation temperature adjustment system includes: an expansion water tank 13 , a stainless steel water pump 14 connected to the expansion water tank 13 , and an intermediate heat exchanger 15 connected to the stainless steel water pump 14 .

The condenser 2, evaporator 5 and intermediate heat exchanger 15 connect three subsystems. The intermediate heat exchanger 15 balances the cold and hot loads of the evaporation temperature regulation system and the condensation temperature regulation system. Through a reasonable valve regulation scheme, the required low-temperature outdoor temperature condition is provided for the evaporator in the air source heat pump system, and the temperature of the cooling water entering the condenser is ensured to be stable, so that the experimental research is no longer restricted by outdoor meteorological conditions and the experimental cost is reduced. It has the advantages of safety, convenience, high economy and good flexibility.

In the condensing temperature regulating system of the present embodiment, a first bypass pipeline 12 is installed at the inlet and outlet of the cooling water circulating water pump 7, a first regulating valve 10 is installed on the first bypass pipeline 12, a second regulating valve 11 is installed on the cooling water inlet 8, and a seventh regulating valve 20 is installed on the cooling water outlet 9. In the evaporating temperature regulating system, a third regulating valve 16 is installed at the inlet of the evaporator 5, a second bypass pipeline 21 is installed at the inlet and outlet of the evaporator 5, a fourth regulating valve 17 is installed on the second bypass pipeline 21, a fifth regulating valve 18 is installed at the inlet of the intermediate heat exchanger 15, a third bypass pipeline 22 is installed at the inlet and outlet of the intermediate heat exchanger 15, and a sixth regulating valve 19 is installed on the third bypass pipeline 22.

The exhaust port of the compressor 1 of the present embodiment is connected with the inlet of the condenser 2, the outlet of the condenser 2 is connected with the inlet of the throttle valve 4 via the drying filter 3, the outlet of the throttle valve 4 is connected with the inlet of the evaporator 5, the outlet of the evaporator 5 is connected with the air intake port of the compressor 1 via the gas-liquid separator 6, the liquid refrigerant flowing out of the condenser 2 is throttled and reduced in pressure in the throttle valve 4 via the drying filter 3, and then enters the evaporator 5 to absorb heat and vaporize, the gaseous refrigerant enters the air intake port of the compressor 1 via the gas-liquid separator 6, is compressed into a high-temperature and high-pressure refrigerant, enters the condenser 2 from the exhaust port of the compressor 1, releases heat to the cooling water in the condenser 2 to become liquid, and performs the next cycle, the opening of the throttle valve 4 is controlled by the superheat of the refrigerant at the outlet of the evaporator 5, and the mass flow rate of the circulating refrigerant in the air source heat pump system is adjusted, when the superheat is small, the opening of the throttle valve 4 is reduced; when the superheat is large, the opening of the throttle valve 4 is increased.

The outlet of the cooling water circulation pump 7 of this embodiment is connected with the inlet of the condenser 2, and the inlet of the cooling water circulation pump 7 is connected with the outlet of the cooling water circulation pump 7 through the first regulating valve 10 to form a first bypass pipeline 12. The outlet of the condenser 2 is connected with the inlet of the cooling water circulation pump 7 through the cooling water outlet 9 and the cooling water inlet 8. The cooling water inlet 8 is connected with the second regulating valve 11. The cooling water outlet 9 is connected with the inlet of the intermediate heat exchanger 15. The outlet of the intermediate heat exchanger 15 is connected with the seventh regulating valve 20. The seventh regulating valve 20 controls the condensation temperature of the condenser 2. When the condensation temperature is reduced, the opening of the seventh regulating valve 20 is increased; when the condensation temperature is increased, the opening is increased, thereby ensuring that the temperature of the cooling water entering the condenser 2 is stable. The first regulating valve 10 controls the cooling water flow of the condenser 2. When the temperature difference between the inlet and outlet of the cooling water in the condenser 2 is reduced, the opening of the first regulating valve 10 is increased to increase the cooling water flow; when the temperature difference between the inlet and outlet of the cooling water in the condenser 2 is increased, the opening is increased, thereby increasing the cooling water flow; when the temperature difference between the inlet and outlet of the cooling water in the condenser 2 is increased, the opening is increased, thereby simulating the user's heating load.

The outlet of the stainless steel water pump 14 of this embodiment is connected to the inlet of the intermediate heat exchanger 15 through the fifth regulating valve 18, and the inlet of the fifth regulating valve 18 is connected to the outlet of the intermediate heat exchanger 15 through the sixth regulating valve 19 to form a third bypass pipeline 22. The outlet of the intermediate heat exchanger 15 is connected to the inlet of the evaporator 5 through the third regulating valve 16, and the inlet of the third regulating valve 16 is connected to the outlet of the evaporator 5 through the fourth regulating valve 17 to form a second bypass pipeline 21. The outlet of the evaporator 5 is connected to the inlet of the stainless steel water pump 14 through the expansion water tank 13. The ethylene glycol aqueous solution flowing out of the evaporator 5 is mixed with the ethylene glycol aqueous solution from the second bypass pipeline 21, and then flows through the expansion water tank 13, the stainless steel water pump 14 in sequence, passes through the fifth regulating valve 18, the sixth regulating valve 19 and the intermediate heat exchanger 15, and then enters the evaporator 5 through the third regulating valve 16 to release heat. The intermediate heat exchanger 15 transfers the heat of the condensing temperature regulation system to the evaporation temperature regulation system to balance the cold and hot loads during the experiment and reduce the experimental cost. In order to prevent the pipes of the evaporation temperature control system from freezing when operating under low temperature conditions, ethylene glycol aqueous solution is selected as the heat exchange medium of the outdoor environment simulation system. In order to realize flexible adjustment of the evaporation temperature, the evaporation temperature of the evaporator 5 is controlled by the sixth regulating valve 19. When the evaporation temperature is reduced, the opening of the sixth regulating valve 19 is increased; when the evaporation temperature is increased, on the contrary, the mass flow of the ethylene glycol aqueous solution entering the evaporator 5 is controlled by the third regulating valve 16 and the fourth regulating valve 17, and the temperature of the ethylene glycol aqueous solution entering the intermediate heat exchanger 15 is controlled by the fourth regulating valve 17. In order to solve the problem that the medium heat exchange temperature difference in the intermediate heat exchanger 15 is large and the water side is easy to freeze The relative flow direction of the heat exchange medium in the intermediate heat exchanger 15 is downstream. The low-temperature ethylene glycol aqueous solution in the heat exchanger exchanges heat with the high-temperature hot water, so that the wall temperature of the heat exchanger is higher than 0°C. A third bypass pipeline 22 is set, and the mass flow rate of the ethylene glycol aqueous solution entering the intermediate heat exchanger 15 is adjusted by the fifth regulating valve 18 and the sixth regulating valve 19. When the temperature of the ethylene glycol aqueous solution is too low, the opening of the fifth regulating valve 18 is reduced to reduce the mass flow rate of the ethylene glycol aqueous solution entering the intermediate heat exchanger 15, ensuring that the water side outlet temperature of the intermediate heat exchanger 15 is not lower than 5°C, which can effectively prevent the water side of the intermediate heat exchanger 15 from freezing and improve the safety of system operation.

The present invention is not limited to the above-mentioned embodiments. Anyone should be aware that any structural changes made under the enlightenment of the present invention, and any technical solutions that are the same or similar to the present invention, fall within the protection scope of the present invention. The technology, shape, and structural parts not described in detail in the present invention are all well-known technologies.

Claims (8)

1. A low-temperature air source heat pump experimental system, characterized in that it includes three subsystems, namely an air source heat pump system, a condensing temperature adjustment system, and an evaporation temperature adjustment system; The air source heat pump system comprises: a compressor (1), a condenser (2) connected to the compressor (1), a drying filter (3) connected to the condenser (2), a throttle valve (4) connected to the drying filter (3), an evaporator (5) connected to the throttle valve (4), and a gas-liquid separator (6) connected to the evaporator (5); The condensing temperature regulating system comprises: a cooling water outlet (9) connected to the condenser (2), a cooling water inlet (8) connected to the cooling water outlet (9), and a cooling water circulation pump (7) connected to the cooling water inlet (8); The evaporation temperature adjustment system comprises: an expansion water tank (13), a stainless steel water pump (14) connected to the expansion water tank (13), and an intermediate heat exchanger (15) connected to the stainless steel water pump (14). 2. A low-temperature air source heat pump experimental system according to claim 1, characterized in that, in the condensing temperature control system, the inlet and outlet of the cooling water circulation pump (7) are equipped with a first bypass pipeline (12), the first bypass pipeline (12) is equipped with a first regulating valve (10), the cooling water inlet (8) is equipped with a second regulating valve (11), and the cooling water outlet (9) is equipped with a seventh regulating valve (20). 3. A low-temperature air source heat pump experimental system according to claim 1, characterized in that, in the evaporation temperature control system, the inlet of the evaporator (5) is equipped with a third regulating valve (16), the inlet and outlet of the evaporator (5) are equipped with a second bypass pipeline (21), the second bypass pipeline (21) is equipped with a fourth regulating valve (17), the inlet of the intermediate heat exchanger (15) is equipped with a fifth regulating valve (18), the inlet and outlet of the intermediate heat exchanger (15) are equipped with a third bypass pipeline (22), and the third bypass pipeline (22) is equipped with a sixth regulating valve (19). 4. A low-temperature air source heat pump experimental system according to claim 2, characterized in that the outlet of the cooling water circulation pump (7) is connected to the inlet of the condenser (2), the inlet of the cooling water circulation pump (7) is connected to the outlet of the cooling water circulation pump (7) through the first regulating valve (10) to form the first bypass pipeline (12), the outlet of the condenser (2) is connected to the inlet of the cooling water circulation pump (7) through the cooling water outlet (9) and the cooling water inlet (8), the cooling water inlet (8) is connected to the second regulating valve (11), the cooling water outlet (9) is connected to the inlet of the intermediate heat exchanger (15), the outlet of the intermediate heat exchanger (15) is connected to the seventh regulating valve (20), the seventh regulating valve (20) controls the condensing temperature of the condenser (2), the first regulating valve (10) controls the cooling water flow of the condenser (2), and the first regulating valve (10) and the seventh regulating valve (20) are adjusted simultaneously to simulate the user's heating load. 5. A low-temperature air source heat pump experimental system according to claim 3, characterized in that the outlet of the stainless steel water pump (14) is connected to the inlet of the intermediate heat exchanger (15) via a fifth regulating valve (18), the inlet of the fifth regulating valve (18) is connected to the outlet of the intermediate heat exchanger (15) via the sixth regulating valve (19) to form the third bypass pipeline (22), the outlet of the intermediate heat exchanger (15) is connected to the inlet of the evaporator (5) via the third regulating valve (16), the inlet of the third regulating valve (16) is connected to the outlet of the evaporator (5) via the fourth regulating valve (17) to form the second bypass pipeline (21), and the outlet of the evaporator (5) is connected to the inlet of the stainless steel water pump (14) via the expansion water tank (13). 6. A low-temperature air source heat pump experimental system according to claim 1, characterized in that the heat exchange medium in the evaporation temperature adjustment system is an ethylene glycol aqueous solution. 7. A low-temperature air source heat pump experimental system according to claim 5, characterized in that the sixth regulating valve (19) controls the evaporation temperature of the evaporator (5), and the third regulating valve (16) and the fourth regulating valve (17) control the mass flow rate of the ethylene glycol aqueous solution entering the evaporator (5). 8. A low-temperature air source heat pump experimental system according to claim 5, characterized in that the relative flow direction of the heat exchange medium in the intermediate heat exchanger (15) is downstream, the fourth regulating valve (17) controls the temperature of the ethylene glycol aqueous solution entering the intermediate heat exchanger (15), and the fifth regulating valve (18) and the sixth regulating valve (19) adjust the mass flow rate of the ethylene glycol aqueous solution entering the intermediate heat exchanger (15).