CN111734137A

CN111734137A - Concrete cooling system based on pulsating heat pipe

Info

Publication number: CN111734137A
Application number: CN201910224815.0A
Authority: CN
Inventors: 张东伟; 周俊杰; 张帆; 蒋二辉; 郭茶秀; 马新灵; 古新
Original assignee: Zhengzhou University
Current assignee: Zhengzhou University
Priority date: 2019-03-24
Filing date: 2019-03-24
Publication date: 2020-10-02

Abstract

The invention discloses a concrete cooling system based on a pulsating heat pipe, which comprises a cooling system and a cooling water circulation system, can be widely applied to the field of concrete cooling, improves the cooling effect, recovers the hydration heat, saves energy and reduces emission. The cooling system mainly comprises a heat-conducting inner pipe, a heat-conducting outer pipe and a pulsating heat pipe, and can effectively utilize the pulsating heat pipe to realize the effects of reducing the internal temperature of the concrete and balancing the temperature difference by matching with water circulation. The cooling water system comprises a water tank, a temperature sensor, an automatic valve and a sealing ring, and not only can provide an efficient condensation end for the heat pipe, but also can recover hydration heat to realize multifunctional utilization of cooling water. The system can rapidly and spontaneously cool the internal temperature of the concrete, balance the temperature difference and recover the hydration heat, and achieves the purposes of high efficiency, energy conservation and environmental protection.

Description

Concrete cooling system based on pulsating heat pipe

Technical Field

The invention relates to the field of concrete construction, in particular to a concrete cooling system based on a pulsating heat pipe.

Background

The large-volume concrete can make its inside temperature rise because of the heat of hydration at the in-process of pouring, and the coefficient of thermal conductivity of concrete is low, and thermal conductivity is poor, and its inside and outside surface can produce great difference in temperature after pouring, produces crack and crackle easily under the effect of temperature stress, so large-volume concrete need set up the cooling measure in order to reduce the inside temperature of concrete and the difference in temperature of inside and outside surface.

Since 1931, the commonly used temperature control measure is the cooling water pipe method, which requires long time for water to flow, and thus has the problem of large consumption of water resources. Meanwhile, in order to maintain and guarantee the temperature difference between the inside and the outside, a heat preservation measure needs to be additionally arranged on the outer side of the concrete, the input cost of equipment is increased, a large amount of electric energy needs to be consumed in the transportation process of cooling water, a large amount of resources are consumed in the using process of the existing cooling water pipe method, and the economic cost is improved. In the existing heat pipe temperature reduction system, the diameter of the used heat pipe is large, so that the working medium flow is greatly influenced by gravity. In order to ensure good heat transfer performance, the heat pipes are generally arranged in a vertical mode, a water tank is difficult to configure in the construction process, the heat transfer process only depends on natural convection heat transfer, the heat transfer amount is small, the cooling capacity is insufficient, and the cooling requirement of large-volume concrete cannot be met.

Disclosure of Invention

In order to solve the problems and achieve the purposes of saving energy and protecting the environment, the invention provides a concrete cooling system based on a pulsating heat pipe, which can spontaneously cool and balance the temperature difference of concrete, and avoid the waste of water resources and electric power resources. The cooling water can provide efficient condensation end and retrieve the hydration heat, realizes the multi-functional utilization of cooling water. The system regulates the temperature of cooling water by regulating the water inlet flow and the water outlet flow through a temperature sensor and an automatic valve. The system completely utilizes the temperature difference between the concrete and the cooling water to realize heat transfer, the cooling process completely and spontaneously runs, no external work is consumed, and the system is energy-saving and environment-friendly.

The concrete cooling system based on the pulsating heat pipe is characterized by consisting of a cooling system and a cooling water system; the cooling system comprises a pulsating heat pipe (1), a heat conduction inner pipe (5) and a heat conduction outer pipe (4), and the pulsating heat pipe (1) is mainly used for reducing the internal temperature of the concrete and balancing the temperature difference; the cooling water system uses cooling water to rapidly cool and recover hydration heat, uses the sealing ring (3) to prevent the water tank from leaking, and controls the temperature of the cooling water through the temperature sensor (10) and the automatic valve (7).

The pulsating heat pipe (1) is formed by bending a copper pipe with a small diameter to form a plurality of dense loops connected in an initial position. After the copper pipe is bent into a dense pipe bundle, the copper pipe is tightly attached to the heat conduction inner pipe (5). The working medium which is easy to change phase, such as acetone, is filled in and then vacuumized. The heat pipe bundle composed of the pulsating heat pipes has a larger heat transfer area, and the internal working medium can transfer a large amount of heat in the process of evaporation and condensation.

The pulsating heat pipe is divided into two parts, wherein one part is the pulsating heat pipe (1) tightly attached to the heat-conducting inner pipe and is main heat-transfer equipment, and heat-conducting silicone grease is filled between the heat-conducting inner pipe (5) and the pulsating heat pipe (1); the other part is a pulsating heat pipe (1) in the inner space of the heat conduction inner pipe (5) and is auxiliary heat transfer equipment.

The heat-conducting outer pipe (4) is placed in concrete, the heat-conducting inner pipe (5) is placed close to the heat-conducting outer pipe (4), an opening is formed in the upper portion of the heat-conducting outer pipe for cooling water to enter, and a gap between the inner pipe (5) and the outer pipe (4) is filled with heat-conducting silicone grease to reduce contact thermal resistance.

According to the cooling water system, cooling water is introduced into the water tank (2) after the pouring is started, and the whole heat conduction inner pipe (5) is filled with the cooling water, so that heat is more easily transferred to the pulsating heat pipe (1). Compared with the traditional natural air cooling heat dissipation, the condensation end of the heat pipe using water as the heat pipe has larger heat exchange coefficient, and can cool concrete more quickly. The heated high-temperature water can be recycled to realize waste heat recovery, and the purposes of energy conservation and environmental protection are achieved. The cooling water system controls the temperature of water in the water tank through a temperature sensor and an automatic valve.

The gain effect of the invention is as follows: (1) the concrete cooling device based on the pulsating heat pipe uses the pulsating heat pipe, and the pulsating heat pipe is spontaneously driven to start by utilizing the temperature difference between the concrete and the cooling water, so that working media in the pipe circularly flow, and the heat in the concrete is transferred to the surface and the water tank. The whole process is carried out spontaneously, no extra work is consumed, and the effects of energy conservation and environmental protection are achieved. (2) Compared with the traditional heat pipe without a liquid absorption core, the pulsating heat pipe adopted by the invention has a simple structure and is easy to manufacture; compared with the traditional heat pipe, the pulsating heat pipe is smaller, the laying can be denser, the heat exchange area is larger in the same space, the heat transfer efficiency is higher, and the pulsating heat pipe is more suitable for being used in the field of concrete. (3) The pulsating heat pipe adopted by the invention has small diameter, wherein the working medium is mainly under the action of surface tension and pressure and is slightly influenced by gravity, so that the installation position of the heat conduction pipe and the placement position of the water tank can be freely selected according to the situation. (4) Compared with the traditional cooling water pipe, the water tank used by the invention can pump water far away, so that water resources are saved; and the heated high-temperature water can be used as domestic water of workers, so that the purpose of waste heat recovery is achieved, and the energy is saved and the environment is protected.

Drawings

FIG. 1 is a view showing installation of the present apparatus.

Fig. 2 and 3 are layout diagrams of pulsating heat pipes of the device.

Fig. 4 is a layout view of the sealing ring of the device.

Wherein 1, pulsating heat pipes; 2. a water tank; 3. a seal ring; 4. a heat conducting outer tube; 5. a heat conducting inner tube; 6. concrete; 7. an automatic valve; 8. a water inlet; 9. a water outlet; 10. a temperature sensor; 11. a seal ring; 12. an automatic valve.

Claims

1. The concrete cooling system based on the pulsating heat pipe is characterized by consisting of a cooling system and a cooling water system; the cooling system comprises a pulsating heat pipe (1), a heat-conducting outer pipe (4) and a heat-conducting inner pipe (5), and the pulsating heat pipe (1) is mainly used for reducing the internal temperature of the concrete and balancing the temperature difference; the cooling water system uses cooling water to rapidly cool and recover hydration heat and consists of a water tank (2), a sealing ring (3), an automatic valve (7) and a temperature sensor (10).

2. The pulsating heat pipe (1) as recited in claim 1, wherein the pulsating heat pipe (1) is formed by bending a copper pipe with a small diameter to form an end-to-end loop, the loop is densely arranged in the heat-conducting inner pipe (5), a working medium with a low boiling point and a characteristic of easy phase change is filled in the pulsating heat pipe (1), and the working medium circularly flows in the pulsating heat pipe (1) when the system works, so that the heat transfer efficiency is improved.

3. The pulsating heat pipe (1) as claimed in claim 2, wherein the pulsating heat pipe (1) is disposed inside the heat-conducting inner pipe (5) and is divided into two parts, one part is the pulsating heat pipe (1) tightly attached to the heat-conducting inner pipe (5) and is a main heat transfer device, and heat-conducting silicone grease is filled between the heat-conducting inner pipe (5) and the pulsating heat pipe (1); the other part is a pulsating heat pipe (1) in the inner space of the heat conduction inner pipe (5) and is auxiliary heat transfer equipment.

4. The heat-conducting inner (5) and outer (4) pipes according to claim 1, wherein the heat-conducting outer pipe (4) is placed in concrete, the heat-conducting inner pipe (5) is placed in close contact with the heat-conducting outer pipe (4), the upper opening is used for cooling water, and a gap between the inner (5) and outer (4) pipes is filled with heat-conducting silicone grease.

5. The cooling water system as claimed in claim 1, wherein cooling water is introduced into the water tank (2) after casting is started to rapidly cool the water tank, the temperature of the cooling water between the water tank (2) and the inner heat conducting pipe (5) is measured by a temperature sensor (10) by using a sealing ring seal (3), and the temperature of the cooling water is controlled by regulating the flow rate of the inlet water and the outlet water.