JPS6229822Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a thermally driven pump.

A heat-driven pump is a device that uses heat to simultaneously transport heat and liquid.A conventionally used general device is explained with reference to Figure 1.A heat-driven pump is a device that uses heat to simultaneously transport heat and liquid. Heating tube 1 and lower heating tube 2
A series of discharge pipes 3 are connected by connecting the discharge ends 1a and 2a, which extend upward and hang downward through a bent part, and a suction pipe 4 is also connected by connecting the suction ends 1b and 2b.
are the bent portions 3a of the discharge pipe 3 and the suction pipe 4, respectively.
4a is located above the upper heating pipe 1, the discharge pipe 3 is provided with a check valve 5 located between the bent portion 3a and the upper heating pipe 1, and the suction pipe 4 is provided with a check valve 5 located at the hanging end. A check valve 6 is interposed therebetween, and the lower ends of the discharge pipe 3 and the suction pipe 4 face into a high temperature water tank 7 and a low temperature water tank 8, respectively. Note that the upper heating tube 1 and the lower heating tube 3 functionally form a heating section 9.

The operating principle of this device is that when the upper heating tube 1 and the lower heating tube 2 are heated with any heat source such as heat supplied from various heat generating devices or high-temperature exhaust gas, the upper heating tube 1,
When the liquid in the lower heating tube 2 boils and the generated bubbles collapse inside or out of the heating tubes, a pressure change occurs, and as a result, the upper heating tube 1
At the same time, the liquid also flows into the lower heating tube 2. By repeating this process continuously, the liquid is transported while absorbing heat.

By the way, the characteristic curve of absorbed heat amount vs. discharge amount in a heat-driven pump having such a structure is as follows:
It is known that the curve looks like the one shown in FIG. In other words, if the vertical axis is the discharge amount G (Kg/h) and the horizontal axis is the absorbed heat amount Q (Kcal/h), this characteristic curve can be roughly divided into three regions A, B, and C. When operated at a corresponding capacity, a stable discharge amount can be obtained. Then, after starting with heat input in region C, if the heat input is gradually decreased, A
It is stable even in this region and operates with a small discharge amount. However, if the pump is started with an input corresponding to areas A and B, the temperature of the entire system will rise sharply, the heating section will dry out, and the pump will not work. The region C is the region in which the heat-driven pump operates stably.

In order to operate a heat-driven pump stably, the amount of heat absorbed must be above a certain value; below this value, operation becomes unstable, and sometimes the working fluid within the heating section must be replaced ( The inflow of low temperature fluid and the outflow of heated fluid may stop, resulting in a dry act. Because of these characteristics, heat-driven pumps should be used within a certain temperature level and calorific value range. However, depending on the conditions of the heat source, before the predetermined temperature level and calorific range are reached, a lower temperature level and calorific process may exist. In such a situation, the operation of the heat-driven pump becomes unstable as described above.

In order to solve these problems, the present invention uses a heat pipe with a known heat flow switch function to control the heating of a heat-driven pump. The operation of the heat-driven pump in the unstable operation region is automatically controlled by using the heat pipe.

The above-mentioned heat pipe, that is, the controlled heat pipe, which has heat flow switching properties by filling a small amount of non-condensable gas such as helium, neon, nitrogen, etc. in addition to the working fluid in advance in the tube forming the heat pipe,
It has heat transfer characteristics as shown in Figure 3. That is, the heat load of the heat source and therefore the heat input of this heat pipe is
As Q ₁ < Q ₂ < Q ₃ < Q ₄ increases, the vapor pressure inside the heat pipe increases, compressing the enclosed noncondensable gas, and increasing the length of the active part of the condensing section. , the interfacial thermal resistance of the condensing section decreases. In this way, when the heat input to the heat pipe increases (decreases), the condenser heat transfer resistance decreases (increases), and both the steam temperature and the amount of heat transfer increase (decrease).

Therefore, in a heat-driven pump in which the heating part is coupled to the condensing part of a controlled heat pipe with such heat transfer characteristics, in a range where the heat load (temperature, amount of heat) of the heat source is low, the heat transfer through the heat pipe is reduced. No heating is applied to the heating section and the heat-driven pump is not activated. Then, the heat load on the heat source increases and effective heat transfer to the heating part starts via the heat pipe, and by making sure that the amount of heat absorbed by the heat-driven pump at that time is around Qc in Figure 2, Operation of the thermally driven pump in unstable operating regions can be automatically suppressed. The design and manufacture of a controlled heat pipe with such heat flow switching properties are well-known knowledge.
Technology can do it.

4 and 5 show an embodiment of the present invention. In FIG. 4, reference numeral A relates to a heat-driven pump, and each part is designated by the same reference numeral as in FIG. B is a controlled heat pipe having a heat flow switching function, 10 is an evaporation part of the heat pipe, 11 is a condensation part, and 12 is a wick lined inside the evaporation part. FIG. 5 shows a large number of heating parts 9a, 9b...
The case is shown in which a heat-driven pump is used, which is formed by arranging the heat pipes in parallel and connecting their inlet and outlet sides to connecting pipes 13 and 14, and the controlled heat pipe has a wide structure. . Both FIG. 4 and FIG. 5 show heating parts 9, 9a, 9a, 9 of the thermally driven pump.
c... is sealed in the condensing section 11 of the heat pipero, and heat is absorbed through the many fins of the heating section.

As described above, the present invention has many advantages, such as limited heat input, efficient operation, and extremely simple structure, allowing conventional heat-driven pumps to be used as is.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the conventional device, Fig. 2 is a diagram showing the characteristics of the conventional device, Fig. 3 is a diagram showing the characteristics of the device of the present invention, and Fig. 4 is an explanatory diagram of the present invention. , FIG. 5 is a perspective view showing another example of the present invention. Codes in the figure: 1 is the upper heating tube, 2 is the lower heating tube,
3, 13 are discharge pipes, 4, 14 are suction pipes, 9, 9
a, 9b, 9c... are heating parts, 10 are evaporation parts, 1
1 is a condensing section, 12 is a heat pump, A is a heat-driven pump, and B is a heat pipe.

Claims (1)

[Scope of utility model registration request] Each of the upper and lower heating pipes located in the heating section has a check valve at one end corresponding to the upper and lower sides, and a discharge pipe and a suction pipe formed by a rising part, a bent part, and a hanging part are connected. The heating section of the heat-driven pump is integrated with the condensing section of a controlled heat pipe that separately seals a required amount of non-condensable gas in addition to the working fluid and has a heat flow switch function. Heat driven pump.