JPS5919276B2 - How to control the amount of heat exchanged - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method for controlling the amount of heat exchanged in a heat exchanger, etc.
In particular, the present invention relates to a method of quickly controlling the amount of heat exchanged between two fluids by changing the heat transfer area between the two fluids.

A partition between two fluids with different temperatures? When heat exchange is performed by contacting the process fluid with a flat surface, the outlet temperature of the process fluid may be too high or too low than the predetermined temperature. A method of changing the inlet temperature of a fluid on the heating or cooling medium side (hereinafter simply referred to as a medium fluid) or a method of adjusting the flow rate of a medium fluid has been used.

However, such conventional heat exchange control methods have the following drawbacks.

(1) The heat capacity of the heat exchanger for i degree control and flow rate adjustment,
There is a delay due to the movement of fluid from the pump and temperature controller.

(2) It is difficult to accurately grasp the dynamic characteristics of the system.

(3) When changing the amount of heat exchanged rapidly, it is not possible to change the temperature difference, which is the dominant factor in determining the amount of heat exchanged, at a predetermined speed due to the heat capacities of the two fluids.

The inventors of the present invention have made extensive studies to solve the drawbacks of the prior art, and have come up with the idea of changing the heat transfer area between two fluids, resulting in the present invention described at the beginning.

The present invention will be specifically described below with reference to the drawings.

FIG. 1 is an explanatory diagram for explaining the present invention in detail,
The heat exchanger 1 is divided into two chambers by double partition walls 2 and 3.

A process fluid A and a medium fluid B having different temperatures are brought into contact by flowing through partition walls 2 and 3, respectively.

On the other hand, fluid 4 is introduced into space 5 surrounded by partition wall 2.3.

When the liquid level H of the liquid 4 rises, the heat transfer area between the two fluids 2 and 3 increases, and the amount of heat exchanged increases.

Furthermore, when the liquid level H decreases, the heat transfer area between the two fluids 2 and 3 decreases (the thermal conductivity of air is much lower than that of the liquid), and the amount of exchanged heat decreases.

By changing the liquid level of the liquid 4 (the height of the liquid surface H) by appropriate means, the amount of exchanged heat can be controlled.

On the unexploded surface, the space 5 containing the liquid 4 has two fluids A
, B may be isolated from the room in which they flow, forming an independent space, or the space 5 may be in communication with either fluid A or B, and therefore the liquid 4 may be fluid A or B itself. I don't mind.

FIG. 2 is a sectional view of a liquid metal refining apparatus used in the present invention.

The process fluid in this example is liquid metal 6, which is a high temperature fluid.

Further, the medium fluid is the cooling fluid 7.

A space 5 between the partition walls 2 and 3 communicates with the process fluid side, and contains a liquid metal 6.

The liquid metal 6 entering from the inlet nozzle 8 comes into contact with the cooling fluid 7 passing through the cooling duct 9 and is cooled by the partition wall 2.3.
The temperature is controlled to a set temperature by the temperature measurement terminal 10.

The precipitated impurities are collected in the mesh 13 of the cold trap, and the purified metal exits from the outlet nozzle 14.

Conventionally, the amount of heat exchanged in the case of excessive cooling has been controlled by changing the flow rate of the cooling fluid 7 or changing the capacity of the heater 11, but in this mechanism, the space 5 between the partition walls 2.3
The amount of heat exchanged is controlled by changing the level of the liquid metal 6 contained in the liquid metal 6 using the cover gas pressure regulator 12 and changing the heat transfer area between the liquid metal 6 and the cooling fluid 7.

FIG. 3 is a sectional view of a liquid metal purity measuring device using the mechanism of the present invention.

The liquid metal 6 that enters from the inlet nozzle 8 is cooled by the cooling fluid γ passing through the cooling duct 9, and when it reaches the impurity precipitation temperature, impurities are precipitated at the orifice 17, causing a change in flow rate.This is the device that detects the impurity concentration. It is.

Conventionally, cooling until impurity precipitation and remelting the impurities accumulated in the orifice 17 relied on adjusting the flow rate of the cooling fluid 7 and changing the capacity of the heater 11, but in this mechanism, in addition to this, or The amount of exchanged heat is controlled by independently raising and lowering the liquid level of the liquid 4 by moving the piston 15 and changing the heat transfer area.

In the device shown in FIG. 3, a space 5 closed by partition walls 2 and 3 is isolated from both the cooling fluid I side and the liquid metal 6 side, and the liquid level is changed by a piston 15 installed at a bellows 16. Let's do it.

By changing the heat transfer area between the two liquids in this manner, cooling for remelting impurities or precipitation of impurities becomes extremely rapid.

The exchange heat amount control method of the present invention has the following advantages.

(1) Since the heat transfer area is changed by changing the liquid level between the partition walls, the troughs are completed in an extremely short period of time. There is no accompanying control time delay, and unlike the case where the amount of heat exchanged is controlled by the valley (2) flow rate change, there is almost no effect on the heat transfer between the two fluids.

-(3) It is easy to accurately grasp the dynamic characteristics of the system.

(4) It can be applied to a wide range of applications such as ordinary heat exchangers, equipment for metal refining and metal purity measurement, and condensers.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the concept of the present invention, FIG. 2 is a cross-sectional view of a liquid metal purification apparatus using the present invention, and FIG. 3 is a cross-sectional view of a liquid metal purity measuring apparatus using the present invention. 1... Heat exchanger, 2, 3... Partition wall, 4
...Liquid, 5...Space, 6...
・Liquid metal, 7... Cooling fluid, 12...
・Cover gas pressure regulator, 15... piston,
A...Process fluid, B...Medium fluid.

Claims (1)

[Claims] 1. In a method of exchanging heat by bringing two fluids with different temperatures into contact across a partition wall, the partition walls are provided in duplicate, a liquid flows between the partition walls, and the liquid level of the fluid between the partition walls is adjusted. A method of controlling the amount of heat exchanged between the two fluids by changing the amount of heat exchanged between the two fluids.