JPH03152365A - Refrigerator - Google Patents

Abstract

PURPOSE:To mount a small flow meter and to measure the entire flow rate by providing an outer passage for bypassing an outer fluid passage passing the interior of a heat exchanger to the heat exchanger, and providing a flow rate measuring unit in the bypass passage. CONSTITUTION:A heat exchanger 1 is divided into blocks by partition plates 5. Outer fluid is introduced from an inlet 2, passed through an outer fluid passage 4 to a room 8 partitioned by the partition plates 5, through another outer fluid passage to a room 9, further similarly passed through a room 10 to an outer fluid outlet 3, and thermally exchanged while passing the passage 4. A bypass tube 6 is provided between the inlet 2 and the room 9 of the heat exchanger, and a flow rate measuring unit 7 is further provided in the tube 6. Flow rate fed by the differential pressure between the inlet 2 and the room 9 of the exchanger is measured by the unit 7. Thus, the entire flow rate can be presumed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a refrigerator, and particularly to a refrigerator in which a heat exchanger is provided with a flow rate measuring device.

[Conventional technology]

Conventionally, in order to accurately control and monitor a refrigerator, it has become necessary to measure the flow rate of an external fluid entering a heat exchanger.

Furthermore, when attempting to cause a rated external flow rate to flow through the refrigerator, it is necessary to detect the flow rate.

However, refrigerators often do not have flow meters, and a method is often used to estimate the flow rate by measuring the pump head (pressure measurement) using the characteristics of the pump head and flow rate. If there is no measured data on the pump's characteristics, or if pressure cannot be measured, the flow rate setting will be very approximate.

Generally, flowmeters are expensive, and the cost becomes more expensive especially as they become larger (larger flow rate), so installing a flowmeter poses an economical problem.

[Problem to be solved by the invention]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a refrigerator having a heat exchanger that can measure the entire flow rate by installing a small flow rate meter.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a refrigerator having a heat exchanger that exchanges heat with an external fluid (chilled water, cooling water, heat source), in which the heat exchanger has an external fluid passage passing through the inside of the heat exchanger. The refrigerator is characterized in that an external passage is provided for bypassing the flow rate, and a flow rate measuring device is provided in the bypass passage.

In the present invention, the external fluid passage passing through the inside of the heat exchanger has a multi-pass configuration, and the bypass passage is provided by bypassing some of the passages, and the heat exchanger It is an evaporator of a refrigerator, and the external fluid passage is the cold water pipe of the evaporator, and a bypass path is provided for the artificial side path, and a bypass path is provided for the outlet side path. It's something that doesn't exist.

Refrigerators include various heat exchangers, such as absorbers, generators, condensers, and heat exchangers for heating dilute solutions. Although the flow rate measuring device can be installed in any heat exchanger, it is particularly preferable to install it in the evaporator as shown above.

[For production]

In the present invention, the flow rate of the external fluid (chilled water, cooling water) is detected, that is, the small flow rate is detected, and the flow rate of the external fluid is estimated, and a small flow meter is used. This allows costs to be reduced.

That is, the total flow rate of the external fluid can be estimated from the pressure loss and flow rate characteristics of the heat exchanger portion and the differential pressure-flow rate characteristics of the bypass passage.

To ensure accuracy, it is best to attach a flow meter to the bypass passage, measure the characteristics of the total flow rate and bypass flow rate, and correct the flow meter.

The obtained flow rate measurements can be used as follows.

(1) Used as a substitute for a water cut-off switch in the safety device of a refrigerator (2) Flow rate setting (3) Flow rate display (4) Used for calculating the amount of heat such as in a freezing container (5) Used for flow rate control (variable flow rate control) For example, in the case of an evaporator, a problem with providing a bypass passage is that if a bypass passage is provided from the inlet to the outlet, in order to keep the outlet temperature constant, the temperature of the bypass fluid is high, so it is necessary to It is necessary to lower the temperature and maintain a constant temperature after mixing with the fluid that has passed through the heat exchanger. (
Figure 2 a) Generally speaking, lowering the temperature of the evaporator, that is, the temperature of the chilled water, will reduce the efficiency of the refrigerator. In the present invention, in order to avoid this, a portion of the bypass flow bypasses only a portion of the heat exchanger, that is, the artificial side, so that a decrease in efficiency can be significantly prevented. (FIG. 2b> [Example] The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 FIG. 1 is a sectional view showing an example of a heat exchanger used in the present invention.

In FIG. 1, 1 is a heat exchanger, and this heat exchanger is divided into blocks by partition plates 5, and external fluid enters from port 2, passes through external fluid passage 4, and is partitioned by partition plates 5. It leads to chamber 8 , through another external fluid passage to chamber 9 , and likewise through chamber 10 to external fluid outlet 3 . and,
Heat is exchanged while passing through the external fluid passage 4.

In such a device, the invention provides that the external fluid population 2
A bypass pipe 6 is provided between the heat exchanger chamber 9 and the heat exchanger chamber 9, and further,
This bypass pipe 6 is provided with a flow rate measuring device 7. The total flow rate can be estimated by measuring the flow rate due to the differential pressure between the external fluid volume 2 and the heat exchanger chamber 9 using the flow rate measuring device 7.

In this example, a bypass pipe is provided between the chamber 9 and the bypass pipe, but it can be installed anywhere where a pressure difference can be generated and a flow rate can be measured as described above. In addition, since such flow rate measurement only requires measurement of a portion of the total flow rate, that is, only the bypass amount, the flow meter may be of a small flow rate type.

Next, the advantage of providing the bypass pipe on the inlet side as described above will be explained with reference to FIG. FIG. 2 is a graph showing the relationship between the heat transfer area of the cold water pipe of the evaporator and the temperature of the external cold water.

Figure 2a shows the chilled water temperature when a bypass pipe is provided between the external fluid inlet and outlet of the heat exchanger. The mainstream temperature decreases from the population temperature a to the outlet temperature C by heat exchange, but
Since the bypass flow does not pass through the heat exchanger, it remains as a.
At the outlet, it is mixed with the main flow, and the overall temperature becomes b. Therefore, in order to maintain the overall temperature at b, the outlet temperature of the main stream needs to be cooler than b.

On the other hand, FIG. 2 shows a case in which bypass pipes are provided at the external fluid inlet of the heat exchanger and at an intermediate portion between the inlet and the outlet. The mainstream is
By the middle it has cooled to a temperature a, -+c', where it mixes with the bypass flow temperature a and rises overall to b',
It passes through the heat exchanger in the latter half and is cooled to b at the exit.

Therefore, if this method is used, there is no need to cool the temperature to below b, and it is efficient.

〔Effect of the invention〕

According to the present invention, since the heat exchanger is provided with a bypass pipe and a flow rate measuring device is provided, the entire flow rate can be measured with a small flow meter, which is advantageous in terms of cost. Further, by providing a bypass pipe for the artificial side path of the heat exchanger, the efficiency of the refrigerator is improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a heat exchanger used in the present invention, and FIG. 2 is a graph showing the relationship between the heat transfer area of the cold water pipe of the evaporator and the temperature of external cold water. DESCRIPTION OF SYMBOLS 1... Heat exchanger, 2... External fluid inlet, 3... External fluid outlet, 4... External fluid passage, 5... Partition plate,
6... Bypass pipe, 7... Flow rate measuring device, 8.9.
10...Room partitioned with a partition board

Claims (1)

[Claims] 1. In a refrigerator having a heat exchanger that exchanges heat with an external fluid, the heat exchanger is provided with an external passage that bypasses an external fluid passage passing through the inside of the heat exchanger, and the bypass passage A refrigerator characterized by being equipped with a flow rate measuring device. 2. The refrigerator according to claim 1, wherein the external fluid passage passing through the heat exchanger has a multi-pass configuration, and a bypass passage is provided to bypass some of the passages. 3. The heat exchanger is an evaporator of a refrigerator, the external fluid passage is a cold water pipe of the evaporator, a bypass path is provided for the inlet side path, and a bypass path is provided for the outlet side path. The refrigerator according to claim 1, characterized in that the refrigerator is not provided with.