Condensation testing apparatus and condensation testing method

Abstract

To provide a dew condensation testing device that can supply water to a water storage part and stabilize the water temperature in the water storage part at the start of a test cycle.SOLUTION: A dew condensation testing device includes: a test chamber 12 in which a sample is arranged; air-conditioning means 23 which adjusts an environment in the test chamber 12; a water storage part 55 which is arranged in the test chamber 12 and to which water is supplied from the outside of the test chamber; and heating means 73. The device heats the water in the water storage part 55 with the heating means 73 to create a high humidity environment in the test chamber 12 and causes dew condensation in the sample 100. The device includes heat exchangers 53a, 53b. The heat exchangers 53a, 53b are located in the test chamber 12, and water passing through the heat exchangers 53a, 53b is supplied to the water storage part 55.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a dew condensation test apparatus for causing dew condensation on a specimen. The present invention also relates to a dew condensation test method.

Background Art

[0002] A dew condensation test in which a specimen is exposed to a high humidity environment and dew condensation is caused on the specimen is known. The dew condensation test is performed using, for example, the dew condensation test apparatus disclosed in Patent Document 1. The dew condensation test apparatus disclosed in Patent Document 1 has a water storage section provided in a test chamber. The water storage section incorporates a heater that heats the water in the water storage section, vaporizes the water in the water storage section, and raises the humidity in the test chamber. Patent Document 1 discloses an example of a dew condensation test. The dew condensation test disclosed in Patent Document 1 is as follows.

[0003] In the dew condensation test disclosed in Patent Document 1, the water storage section is preliminarily filled with water. First, the inside of the test chamber is maintained in a relatively low temperature state, and the specimen is exposed to the environment in this relatively low temperature state (exposure step). Next, the water in the water storage section is heated by a heater to vaporize the water in the water storage section. At this time, the amount of heat of the heater is controlled so that the temperature of the water in the water storage section draws a certain rising curve. As the water in the water storage section vaporizes, the humidity (relative humidity, the same hereinafter) in the test chamber rises, the water vapor touches the low-temperature specimen, and the water vapor condenses to cause dew condensation and generate water droplets (hereinafter, the water droplets are also referred to as dew condensation) (dew condensation generation step). Thereafter, the humidity in the test chamber is lowered to evaporate the dew condensation. Also, the temperature in the test chamber is lowered (temperature drop step). By lowering the temperature in the test chamber, the temperature of the water in the water storage section is lowered. That is, the water in the water storage section is cooled by the air in the test chamber.

[0004] The condensation test disclosed in Patent Document 1 consists of a single test cycle comprising: an exposure step in which the test chamber is maintained at a relatively low temperature and the test specimen is exposed to a low-temperature environment; a condensation generation step in which the water in the reservoir is heated to vaporize the water in the reservoir and cause condensation on the test specimen; and a temperature reduction step in which the humidity in the test chamber is reduced to evaporate the condensation and also to lower the temperature in the test chamber. This test cycle is repeated multiple times. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Patent No. 6092816 [Overview of the project] [Problems that the invention aims to solve]

[0006] Conventional condensation tests begin with the reservoir filled with water and repeat a series of test cycles using that water. In principle, the water in the reservoir is not replaced or new water is added during the test. Therefore, when using conventional condensation testing equipment, the water in the reservoir may become more concentrated as the number of test cycles increases. In other words, a condensation test forces condensation (water droplets) to form on the surface of the test specimen, and organic and inorganic substances originating from the specimen may be mixed in with the condensation. When these condensation droplets fall into the reservoir, impurities from the specimen will be mixed into the water in the reservoir.

[0007] The condensation test involves heating and evaporating the water in the reservoir multiple times, which may lead to the concentration of impurities within the reservoir. Furthermore, if volatile substances such as oils and fats are mixed in with the condensation, these substances may re-vaporize and adhere to the test specimen, potentially negatively impacting the condensation test.

[0008] Therefore, the inventors decided to replace the water in the reservoir after each test cycle. The prototype condensation test apparatus had a water supply tank installed outside the test chamber, and water was supplied from this tank to a water reservoir installed inside the test chamber. However, when using the prototype and performing condensation tests by replacing the water in the reservoir after each test cycle, we encountered a problem in that the water temperature in the reservoir at the start of each test cycle sometimes did not fall within the specified range. Furthermore, the reason why the water temperature in the reservoir does not fall within the specified range is presumably because the water temperature in the water supply tank installed outside the test chamber is affected by the temperature of the location where the condensation test device is installed.

[0009] The present invention aims to solve the above-mentioned new problems and to provide a condensation test apparatus that can supply water to the water reservoir and keep the water temperature inside the reservoir within a predetermined range at the start of the test cycle. [Means for solving the problem]

[0010] A condensation test apparatus for solving the above-mentioned problems is a condensation test apparatus comprising a test chamber in which a test specimen is placed, an air conditioning means for adjusting the environment inside the test chamber, a water reservoir located inside the test chamber and supplied with water from outside the test chamber, and a heating means, wherein the heating means heats the water in the water reservoir to create a high-humidity environment inside the test chamber and causes condensation on the test specimen, and the apparatus further comprises a heat exchanger, the heat exchanger is located inside the test chamber, and the water that has passed through the heat exchanger is supplied to the water reservoir.

[0011] The condensation test apparatus in this embodiment has an air conditioning means, which adjusts the temperature inside the test chamber. The condensation test apparatus in this embodiment also has a heat exchanger, which is located inside the test chamber, and the water that passes through the heat exchanger is supplied to the water reservoir. As a result, the water passing through the heat exchanger exchanges heat with the air inside the test chamber, and the temperature of the water supplied to the water reservoir falls within a predetermined range.

[0012] In the above-described embodiment, it is desirable that the reservoir has a drain valve for discharging water, and that the drain valve is opened and closed by an electrical signal.

[0013] Since the dew condensation test apparatus of this aspect includes a drain valve, the water in the water storage section can be drained and replaced with newly supplied water. Further, since the drain valve is opened and closed by an electric signal, the drain valve can be opened at an appropriate time according to a signal from a control device or the like.

[0014] In the above-described aspect, it is desirable that the heat exchanger is a spiral tube.

[0015] The heat exchanger employed in the dew condensation test apparatus of this aspect has a simple structure, yet can maintain the temperature of the water supplied to the water storage section at a constant level.

[0016] In the above-described aspect, it is desirable to have a plurality of the heat exchangers.

[0017] According to this aspect, the temperature of the water supplied to the water storage section becomes more stable.

[0018] In the above-described aspect, it is desirable that the heat exchanger is located at a position closer to the side wall of the test chamber.

[0019] According to this aspect, it is possible to suppress the condensation of the vapor generated from the water storage section before reaching the test specimen. For this reason, more dew condensation can be caused on the test specimen.

[0020] In the above-described aspect, it is desirable to have a holding member that holds the heat exchanger, and a ventilation port is provided in the holding member.

[0021] In the dew condensation test apparatus of this aspect, the heat exchanger is held by the holding member. The holding member employed in this aspect has a ventilation port, so ventilation to the heat exchanger is ensured while holding the heat exchanger, and the heat exchange efficiency is high.

[0022] An aspect regarding the dew condensation test method is a dew condensation test method performed using the dew condensation test apparatus described in any of the above, the method including: a step of exposing a test specimen to a temperature environment by adjusting the temperature in the test chamber to a constant temperature; a dew condensation generation step of heating the water in the water storage part by the heating means to gradually increase the humidity in the test chamber to cause dew condensation on the test specimen; a temperature drop step including dropping the temperature in the test chamber by the air conditioning means, which is a step following the dew condensation generation step; and a water supply step of supplying water to the water storage part from outside the test chamber through the heat exchanger in parallel with the exposing step.

[0023] In the dew condensation test method of this aspect, since water is supplied to the water storage part for each test cycle, concentration of contaminants is unlikely to occur. Also, since the temperature of the water supplied to the water storage part can be kept within a predetermined range, a highly reliable dew condensation test can be performed.

Effect of the Invention

[0024] The dew condensation test apparatus of the present invention can supply water to the water storage part for dew condensation. Also, in the dew condensation test apparatus of the present invention, the temperature of the water supplied into the water storage part is stable, and the water temperature in the water storage part at the start of the test cycle can be kept within a certain range.

Brief Description of the Drawings

[0025] [Figure 1] It is a perspective view of the dew condensation test apparatus of an embodiment of the present invention. [Figure 2] It is a cross-sectional view of the heat insulation tank of the dew condensation test apparatus of FIG. 1. [Figure 3] It is a cross-sectional view taken along line A-A of FIG. 2. [Figure 4] It is a perspective view of the inside of the test chamber of the dew condensation test apparatus of FIG. 1. [Figure 5] It is a perspective view of the heat exchanger and the holding member. [Figure 6] It is a piping system diagram of the dew condensation test apparatus of FIG. 1. [Figure 7] It is a flowchart of the dew condensation test. [Figure 8]The following shows the status of each piece of equipment during the condensation test: (a) is a graph showing the changes in temperature and humidity in the test room; (b) is a graph showing the changes in water temperature in the water storage container; (c) is a time chart showing the opening and closing of the drain valve; (d) is a time chart showing the on and off of the pump; and (e) is a time chart showing the on and off of the air conditioning equipment. [Modes for carrying out the invention]

[0026] Embodiments of the present invention will be described below. The condensation test apparatus 1 of this embodiment consists of a main unit 2 and a condensation humidifier 50. The main unit 2, as shown in Figure 2, is a device that includes a test chamber 12 in which the test specimen 100 is placed, and an air conditioning device 23 (air conditioning means) for adjusting the environment inside the test chamber 12. The upper part of the main unit 2 is composed of an insulated tank 7. The insulated tank 7 has a main body 3 and a door 5, as shown in Figure 2.

[0027] As shown in Figure 2, there is a partition wall 10 inside the insulated tank 7, which is on the inner tank side of the main body 3. The partition wall 10 divides the inside of the insulated tank 7 into a test chamber 12 and an air conditioning unit 15. Openings are provided at the upper and lower ends of the partition wall 10. The opening at the upper end of the partition wall 10 functions as an air outlet 20, and the opening at the lower end of the partition wall 10 functions as an air inlet 21. The test room 12 and the air conditioning unit 15 are connected at two points: the air outlet 20 and the air inlet 21.

[0028] The air conditioning unit 15 is an air conditioning ventilator that communicates with the test chamber 12 in an annular manner, and contains air conditioning equipment 23 and a blower 30. The air conditioning equipment 23 consists of an air conditioning humidifier 31, a cooling device 32, and a heating device 33. The cooling device 32 has a cooling function to lower the temperature inside the test chamber 12 and a dehumidifying function to lower the humidity inside the test chamber 12, as is well known. When the blower 30 is started, air from the test chamber 12 is introduced into the air conditioning unit 15 from the air inlet 21. The air conditioning unit 15 then enters a ventilated state, and the air comes into contact with the air conditioning equipment 23, where heat exchange and humidity adjustment take place. The adjusted air is then blown back into the test chamber 12 from the air outlet 20.

[0029] Furthermore, a temperature sensor 37 and a humidity sensor 38 are provided near the air outlet 20. The signals from the temperature sensor 37 and the humidity sensor 38 are input to the control device 18. The control device 18 then compares the detected values ​​of the temperature sensor 37 and the humidity sensor 38 with their respective set values. The main unit 2 is capable of creating a desired environment within the test chamber 12. The control device 18 operates the blower 30 to create a ventilated state inside the air conditioning unit 15 and controls the air conditioning equipment 23 so that the detected values ​​of the temperature sensor 37 and humidity sensor 38 approach the temperature and humidity of the set environment. In other words, by operating the blower 30, the air in the test chamber 12 is introduced from the air inlet 21 to the air conditioning unit 15, passes through the air conditioning equipment 23 in the air conditioning unit 15, and has its temperature and humidity adjusted. Then, the temperature and humidity adjusted air is returned to the test chamber 12 from the air outlet 20, creating an environment with the desired temperature and humidity in the test chamber 12.

[0030] Next, we will explain the humidifier 50 for condensation. As shown in Figure 1, the humidifier 50 for condensation consists of a water supply tank 51, a water supply pump 52, heat exchangers 53a and 53b, a water storage container (water storage section) 55, and a drain valve 56. Furthermore, as shown in Figures 2, 3, and 4, a condensation heater (heating means) 73 is provided in the water storage container (water storage section) 55.

[0031] The water supply tank 51 is a known resin tank. The water supply pump 52 is a known electric pump. As shown in Figures 2, 3, and 4, the heat exchangers 53a and 53b are coil-shaped structures made of bare copper pipes wound in a spiral, each forming a series of water passages. The heat exchangers 53a and 53b are mounted vertically as shown in Figure 5, with the upper side being the water inlet 80. The lower ends of the heat exchangers 53a and 53b are outlets 81 and are bent downwards.

[0032] The water storage container (storage section) 55 is a shallow tray made of metal, resin, or ceramic. As shown in Figure 4, the water storage container (storage section) 55 has a bottom 58 and four vertical walls 71a, 71b, 72a, and 72b, and its top surface is completely open. That is, the water storage container 55 has an opening 57 on its top surface. The bottom 58 of the water storage container 55 also has a drain port 60 (see Figure 6). The water storage container 55 used in this embodiment has a rectangular planar shape. The water storage container 55 has legs 61, and the part where water is stored is supported by the legs 61 and raised from the floor surface. A water temperature sensor 83 (see Figure 2) is attached to the water storage container 55. A condensation heater (heating means) 73 is positioned at the bottom of the water storage container 55. The condensation heater (heating means) 73 is a known electric heater. The drain valve 56 is a known solenoid valve and is opened and closed by an electrical signal.

[0033] In this embodiment, as shown in Figure 4, the heat exchangers 53a and 53b are held by the holding members 63a and 63b and are attached to the side of the water storage container 55. As shown in Figure 5, the retaining members 63a and 63b are L-shaped plates with a horizontal wall 66 and a vertical wall 67. Multiple ventilation openings 70 are provided in the vertical wall 67. The ventilation openings 70 are rectangular slits.

[0034] As shown in Figure 4, one retaining member 63a is attached to one end of the vertical wall 71a on one long side of the water storage container 55, and the other retaining member 63b is attached to the other end of the vertical wall 71b on the other long side of the water storage container 55. The retaining members 63a and 63b are connected at the free end of the horizontal wall 66 to the upper end of the vertical walls 71a and 71b on the long side of the water storage container 55. Therefore, the retaining member 63 is attached in a state that it protrudes laterally from the vertical walls 71a and 71b on the long side of the water storage container 55. The heat exchangers 53a and 53b are fixed to the retaining members 63a and 63b by fittings (not shown). Since the heat exchangers 53a and 53b are located in the area enclosed by the horizontal wall 66 and vertical wall 67 of the retaining member 63, the heat exchangers 53a and 53b are located to the side of the opening 57 of the water storage container 55 and do not overlap with the opening 57 in plan. Furthermore, the lowest part of the helical sections of the heat exchangers 53a and 53b is above the height of the opening 57 of the water storage container 55. In other words, the height of the helical sections of the heat exchangers 53a and 53b is generally higher than the opening 57 of the water storage container 55. Furthermore, the lowest parts of the heat exchangers 53a and 53b, including the outlet 81, are located higher than the expected water level in the water storage container 55. The two heat exchangers 53a and 53b are located on the outside of the water storage container 55, at diagonal positions.

[0035] As shown in Figures 2, 3, and 4, the water storage container 55 and the heat exchangers 53a and 53b are located inside the test chamber 12 of the main unit 2. Specifically, the legs 61 of the water storage container 55 are in contact with the floor surface 75 of the test chamber 12, and the bottom 58 of the water storage container 55 is raised above the floor surface 75. As shown in Figure 3, the water storage container 55 is located in the center of the width direction of the test chamber 12 when viewed from the door 5 side, and the two heat exchangers 53a and 53b are located close to the side walls 76a and 76b of the test chamber 12. In this embodiment, the water storage container 55 and the heat exchangers 53a and 53b are integrated and can be attached to and detached from the test chamber 12.

[0036] The water supply tank 51, water supply pump 52, and drain valve 56 are all located outside the main unit 2, as shown in Figure 1. In other words, the water supply tank 51, water supply pump 52, and drain valve 56 are located outside the test chamber 12. The components of the condensation humidifier 50 are connected by piping as shown in Figures 1 and 6. Specifically, the suction port of the water supply pump 52 is inserted into the water supply tank 51. The water supply pipe 62 to which the water supply pump 52 is connected is branched into two branch pipes 68a and 68b within the test chamber 12, and connected to the upper water inlets 80 of the heat exchangers 53a and 53b. Specifically, branch pipe 68a is connected to the upper water inlet 80 of heat exchanger 53a, and branch pipe 68b is connected to the upper water inlet 80 of heat exchanger 53b. The lower outlets 81 of the heat exchangers 53a and 53b are positioned above the water level in the water storage container (water storage section) 55. In other words, the outlets 81 of the heat exchangers 53a and 53b are open to the space above the water level in the water storage container (water storage section) 55. A drain outlet 60 located at the bottom 58 of the water storage container 55 is led to the outside of the test chamber 12 via a drain pipe 82 and connected to a drain valve 56. The piping in the test chamber 12 (branch pipes 68a, 68b and drain pipe 82) uses heat-resistant tubing such as silicone tubing.

[0037] Water from the water supply tank 51 is drawn into the water supply pump 52 and introduced into the upper water inlets 80 of the heat exchangers 53a and 53b. The water introduced into the heat exchangers 53a and 53b flows through a spiral pipe to the outlet 81 and is introduced into the water storage container (storage section) 55. Since the heat exchangers 53a and 53b are located inside the test chamber 12, the water flowing through the heat exchanger 53 exchanges heat with the air inside the test chamber 12 as it passes through the spiral pipe, causing its temperature to change. If the temperature inside the test chamber 12 is lower than the temperature of the room where the water supply tank 51 is located, the heat from the water is released into the test chamber 12 as it passes through the heat exchangers 53a and 53b, and the temperature of the water introduced into the water storage container (storage section) 55 will be lower than the temperature of the water inside the water supply tank 51. When the drain valve 56 is opened, the water in the water storage container (storage section) 55 is drained outside the test chamber 12.

[0038] The condensation test apparatus 1 of this embodiment is an apparatus for performing a condensation test. For the condensation experiment, as shown in Figures 2, 3, and 4, a highly breathable shelf 85 made of mesh or similar material is installed on the middle level of the test chamber 12, and the test specimen 100 is placed on the shelf 85. The test specimen 100 is placed directly above the water storage container 55 in the plane. The test specimen 100 is also covered with a non-breathable covering member 101.

[0039] As described above, the condensation test includes a "breathing process" in which the test chamber is first maintained at a relatively low temperature and the test specimen is exposed to this relatively low temperature environment; a "condensation generation process" in which the water in the water storage container 55 is heated to vaporize the water in the water storage container 55, increasing the humidity in the test chamber 12 and causing condensation on the test specimen; and a "temperature reduction process" in which the temperature and humidity are lowered after maintaining a relatively high temperature environment, and these steps are repeated.

[0040] In this embodiment, in addition to this process, a "water supply process" in which water supplied from outside the test chamber 12 and having passed through the heat exchangers 53a and 53b is supplied to the water storage container 55, and a "drainage process" in which the water in the water storage container 55 is drained are automatically performed by signals from the control device 18. The water supply process is performed in parallel with the bleaching process. The drainage process is performed in parallel with the temperature reduction process. In the condensation test apparatus 1 of this embodiment, the control device 18 stores a program that automatically executes each step of the condensation test. In other words, in this embodiment, the condensation test apparatus 1 automatically executes the series of steps shown in the flowchart of Figure 7 by a computer built into the control device 18. Specifically, one test cycle consists of sequentially executing the bleaching process, water supply process, condensation generation process, drainage process, and temperature reduction process.

[0041] In the condensation test, the temperature and humidity inside the test chamber 12 follow a trajectory as shown in the graph in Figure 8(a). The water storage container 55 sometimes contains water and sometimes does not, as shown in Figure 8(b), and the water temperature follows a trajectory as shown in the graph in Figure 8(b). The drain valve 56 is opened only during the drainage process and is switched on and off at the timings shown in Figure 8(c). Specifically, the drain valve 56 is turned on at the end of the condensation generation process to drain the water from the water storage container 55. The water supply pump 52 is driven only during the water supply process and is switched on and off at the timings shown in Figure 8(d). Specifically, the water supply pump 52 is driven at the start of the bleaching process to supply water to the water storage container 55. The air conditioning equipment 23 is driven and stopped at the timings shown in Figure 8(e). Specifically, the air conditioning equipment 23 (air conditioning means) is driven during the bleaching process, water supply process, drainage process, and temperature reduction process, and is stopped during the condensation generation process.

[0042] The details of the condensation test will be explained below in order. The bleaching process is carried out during period A in Figure 8. As shown in Figure 8(e), the air conditioning equipment 23 is driven to control the temperature inside the test chamber 12 to a low temperature of about 10 degrees Celsius, as shown in Figure 8(a). The test specimen 100 is then exposed to this low-temperature environment for a certain period of time. By placing the test specimen 100 in a low-temperature environment for a certain period of time, the surface temperature and internal temperature of the test specimen 100 become as low as the temperature inside the test chamber 12. Furthermore, in the bleaching process, the humidity inside the test chamber 12 is increased as shown in Figure 8(a) in order to smoothly transition to the next condensation generation process. Specifically, the humidifier 31 for air conditioning of the air conditioning equipment 23 is driven to increase the humidity inside the test chamber 12.

[0043] The water supply process involves starting the water supply pump 52 as shown in Figure 8(d) to draw water from the water supply tank 51 and introducing it into the water storage container 55 via the heat exchangers 53a and 53b. During this process, the water does not accumulate in the heat exchangers 53a and 53b but passes through them. During the water supply process, the drain valve 56 is closed as shown in Figure 8(c). The water supply process is carried out during period A in Figure 8 and is performed in parallel with the bleaching process. During the bleaching process, the temperature inside the test chamber 12 is low, as shown in Figure 8(a). Since the heat exchangers 53a and 53b are located inside the test chamber 12, they are in a low-temperature environment, and the water passing through the heat exchangers 53a and 53b loses heat and its temperature decreases. Therefore, the water storage container 55 is supplied with water cooled by the heat exchangers 53a and 53b. Also, since the temperature inside the test chamber 12 is controlled to a constant temperature by the air conditioning equipment 23, the water discharged from the heat exchangers 53a and 53b is relatively low in temperature.

[0044] In this embodiment, two heat exchangers 53a and 53b are provided in the test chamber 12, and water supplied branched from the water supply pipe 62 passes through these heat exchangers 53a and 53b. As a result, the water supplied to the water storage container 55 is at a temperature relatively close to the temperature inside the test chamber 12.

[0045] Furthermore, in the main unit 2 used in this embodiment, temperature-controlled air is blown from the air outlet 20 into the test chamber 12, and the air inside the test chamber 12 is drawn into the air inlet 21. As a result, the inside of the test chamber 12 becomes a ventilated environment, and the air blows on the heat exchangers 53a and 53b, promoting heat exchange. In particular, the holding members 63a and 63b of the heat exchangers 53a and 53b used in this embodiment have multiple vents 70 in the vertical wall 67, so they do not obstruct the passage of air. As a result, there are many opportunities for the air to come into contact with the heat exchangers 53a and 53b, and the heat exchange efficiency is high.

[0046] In the water supply process, as shown in Figure 8(d), the water supply pump 52 is driven for a certain period of time during period A in Figure 8, and when the required amount of water is introduced into the water storage container 55, the water supply pump 52 is stopped. In this embodiment, the height of the discharge ports 81 of the heat exchangers 53a and 53b is set higher than the water level in the water storage container 55. Therefore, the water inside the heat exchangers 53a and 53b is replaced by air and discharged, and is less likely to remain inside the heat exchangers 53a and 53b. In other words, in this embodiment, water is introduced into the upper water inlet 80 of the heat exchangers 53a and 53b and discharged from the lower outlet 81. As a result, the water inside the heat exchangers 53a and 53b is biased downward by gravity. On the other hand, the lower outlet 81 is open to the air and does not come into contact with the water surface, making it easy for air to enter. Furthermore, the heat exchanger 53 has no internal obstructions such as valves. As a result, air enters the heat exchangers 53a and 53b from the outlet 81, and the water inside the heat exchanger 53 is replaced by air before being discharged.

[0047] The condensation generation process is performed during the period B shown in Figure 8. In the condensation generation process, the condensation heater (heating means) 73 is energized to heat the water in the water storage container (water storage section) 55. Here, it is desirable for the water temperature to rise in a predetermined upward curve. In this embodiment, the water temperature in the water storage container 55 is monitored by a water temperature sensor 83, and the condensation heater 73 is PID controlled so that the water temperature rises in a constant upward curve. As a result, the water in the water storage container 55 rises in temperature following a trajectory as shown in the graph in Figure 8(b).

[0048] According to the condensation test apparatus 1 of this embodiment, the temperature of the water supplied to the water storage container 55 from outside the test chamber 12 in the water supply process is stable at a low temperature, so the water temperature in the water storage container 55 at the start of the condensation generation process is relatively low. Therefore, the water temperature rise in the condensation generation process can start from a low water temperature state, and an ideal temperature rise can be achieved. In the condensation process, the water vaporizes as the water temperature rises, and the humidity inside the test chamber 12 reaches a saturated or near-saturated state, as shown in Figure 8(a). Since the temperature of the test specimen 100 is lowered by the bleaching process in period A, water vapor condenses on the surface and inside the test specimen 100, causing condensation.

[0049] In this embodiment, there is a water storage container 55 in the center of the lower part of the test chamber 12, and the heat exchangers 53a and 53b are positioned to the side of it. In relation to the test chamber 12, the two heat exchangers 53a and 53b are positioned close to the side walls 76a and 76b of the test chamber 12. Therefore, the heat exchangers 53a and 53b are located away from the opening 57 of the water storage container 55, and the heat exchangers 53a and 53b do not obstruct the rise of water vapor generated from the water storage container 55. In other words, there are virtually no obstacles between the opening 57 of the water storage container 55 and the test specimen 100, and the water vapor generated from the water storage container 55 rises straight up and is contained within the cover member 101. Therefore, a large amount of condensation can be generated on the surface and inside of the test specimen 100.

[0050] Furthermore, as described above, in this embodiment, water is less likely to remain in the heat exchangers 53a and 53b. Therefore, the heat load is smaller compared to the case where water remains in the heat exchangers 53a and 53b. Consequently, in the condensation generation process, it is less likely to hinder the rise in temperature and humidity inside the test chamber 12, and a large amount of condensation can be generated on the surface and inside of the test specimen 100.

[0051] During period B, when the condensation generation process is being carried out, the air conditioning equipment 23 is stopped, as shown in Figure 8(e). During the condensation generation process, the water in the water storage container 55 becomes hot, so the temperature inside the test chamber 12 rises in accordance with the water temperature, as shown in the graph in Figure 8(a).

[0052] Once the condensation generation process is complete, the drainage process is carried out. Specifically, during period C after the completion of the condensation generation process, a signal from the control device 18 opens the drain valve 56 as shown in Figure 8(c), and the water in the water storage container 55 is drained. This stops the humidification by water vapor from the water storage container 55.

[0053] Furthermore, the temperature reduction process is carried out in parallel with the drainage process. The temperature reduction process is carried out during period C in Figure 8. In the temperature reduction process, as shown in Figure 8(e), the air conditioning equipment 23 is driven again to lower the temperature inside the test chamber 12 to a low temperature of about 10 degrees Celsius, as shown in the graph in Figure 8(a), and also to reduce the humidity. As a result, the condensation adhering to the test specimen 100 evaporates. In other words, the temperature reduction process functions as a drying process for the test specimen 100. As described above, since the water in the water storage container 55 is drained during the drainage process, humidification stops during the temperature reduction process. Therefore, the humidity inside the test chamber 12 decreases more rapidly during the temperature reduction process, and as a result, the evaporation of condensation adhering to the test specimen 100 is promoted. Furthermore, since the high-temperature water in the water storage container 55 is discharged by the aforementioned drainage process, the temperature of the test chamber 12 decreases smoothly. That is, since water is a substance with a large heat capacity, a lot of cooling energy is required to lower its temperature. In this embodiment, since the high-temperature water in the water storage container 55 is discharged by the drainage process, the thermal energy contained in the water storage container 55 does not hinder the decrease in temperature of the test chamber 12.

[0054] The above steps complete one test cycle. In this embodiment, the second and third tests are subsequently conducted. Subsequent condensation tests are the same as the first condensation test described above, with the bleaching process, water supply process, condensation generation process, drainage process, and temperature reduction process being carried out in sequence. The second bleaching process is carried out here, following the temperature reduction process of the first condensation test. Since the temperature inside the test chamber 12 is lowered during the first temperature reduction process, the second bleaching process will maintain the temperature inside the test chamber 12 that was lowered during the first temperature reduction process. On the other hand, since the humidity inside the test chamber 12 is lowered during the first temperature reduction process, when the second bleaching process begins, the humidity inside the test chamber 12 will be increased by the air conditioning equipment 23.

[0055] At the start of the second condensation test, the water storage container 55 is empty, and new water is supplied to the water storage container 55 during the second water supply process. In this way, according to this embodiment, the water in the water storage container 55 is replaced with each test cycle. Therefore, impurities originating from the test specimen 100 are not concentrated, and the test cycle can be repeated under the same conditions each time.

[0056] In the embodiments described above, a heat exchanger with a structure in which bare copper tubes are wound into a coil was given as an example, but the present invention is not limited to this configuration. For example, a finned tube, such as an aerofin tube, could be used as a heat exchanger, and the tube could simply be routed into the test chamber 12. Alternatively, a plate fin heat exchanger could be used. The number of heat exchangers is arbitrary; there may be one, or there may be three or more. In other words, there may be one or more heat exchangers.

[0057] In the embodiment described above, the main unit 2 employing the test chamber 12 and the air conditioning unit 15 are connected at two points: an upper air outlet 20 and a lower air inlet 21. Air is introduced into the air conditioning unit 15 from the lower air inlet 21, and the adjusted air is blown into the test chamber 12 from the upper air outlet 20. However, the present invention is not limited to this configuration. In other words, the layout and components of the test room and air conditioning unit are arbitrary. Air may be introduced into the air conditioning unit 15 from the top and blown out into the test room 12 from the bottom. Air may also be blown out from near the center of the back wall, or from the left or right sides of the back wall. The air conditioning unit may be located at the bottom of the test room, with air entering and exiting from the floor side of the test room. The type of blower is arbitrary; it can be a centrifugal blower such as a sirocco fan, or an axial flow blower.

[0058] In the embodiments described above, a drain valve 56 that is opened and closed by an electrical signal, such as a solenoid valve, was used, but a manual valve may be used instead. In the embodiments described above, the drain valve 56 is opened to drain the water from the water storage container 55 and replace the water in the water storage container 55 at the end of each test cycle, but this configuration is not essential. For example, the water may be drained at predetermined intervals. If this configuration is adopted, it is desirable to use a manual valve for the drain valve.

[0059] In the embodiments described above, the humidifier 50 for condensation was equipped with a drain valve 56, but the drain valve 56 is not essential. For example, it is also possible to provide an overflow section such as an overflow pipe in the water storage container 55 and drain excess water from the overflow section. Furthermore, the act of replacing the water in the water storage container 55 is not essential. In other words, although the motivation for developing this invention was to prevent the concentration of water in the water storage container 55, this invention is also applicable when the condensation test is continued simply by adding water without replacing the water in the water storage container 55. In this case as well, the drain valve 56 is not essential. Even in these modified configurations, due to the external water supply, the water temperature in the reservoir at the start of the test cycle may not fall within a predetermined range, and it is recommended to adopt the configuration of the present invention. In particular, in the first test cycle, water is supplied from the water supply tank 51 to the empty reservoir 5, so the water temperature in the water supply tank 51, which is installed outside the test chamber 12, is affected by the temperature of the location where the condensation test device is installed, and the water temperature in the reservoir 55 may not fall within a predetermined range. This problem is resolved by applying the present invention.

[0060] The amount of water supplied to the water storage container 55 can be controlled, for example, by the operating time of the water supply pump 52. A water volume sensor, such as a float, may also be provided in the water storage container 55. An overflow pipe or the like may also be provided in the water storage container 55.

[0061] As described in the above-mentioned embodiment, it is preferable to start the water supply process from the beginning of the bleaching process, but the present invention is not limited thereto, and water supply may be started in the middle of the bleaching process. Similarly, while it is preferable for the drainage process to begin at the start of the temperature reduction process, it is not limited to this, and drainage may be started midway through the temperature reduction process.

[0062] As explained above regarding the temperature decrease process and shown in the graph in Figure 8, a relatively high-temperature environment is maintained during the initial stages of the temperature decrease process. However, maintaining a relatively high-temperature environment during the temperature decrease process is not essential. If an experimental program that does not maintain a high-temperature state is adopted, the drainage process will be carried out during the temperature decrease.

[0063] In the above-described embodiment, the water supply tank 51 and water supply pump 52 are installed outside the main unit 2, but these devices may also be located inside the main unit 2. For example, the water supply tank 51 may be located below the insulated tank 7. Even in this case, the water temperature in the water supply tank 51 is affected by the temperature of the room in which the main unit 2 is installed, thus achieving the effects of the present invention. Furthermore, since there is a heat source such as a compressor inside the main unit 2, the temperature of the air inside the main unit 2 may be high. Therefore, when adopting a layout in which the water supply tank 51 is installed inside the main unit 2, it is recommended to adopt the configuration of the present invention. Note that the water supply tank 51 and water supply pump 52 are not mandatory; for example, water may be supplied to the water storage container 55 by directly connecting it to the water supply pipe. The water supply pump 52 can also be omitted by installing the water supply tank 51 at a high position and supplying water to the water storage container 55 by gravity. The water supply tank 51 is not exclusively for the condensation test apparatus 1; it may be one used for other purposes. In short, the water supply tank 51 and the water supply pump 52 do not necessarily have to be part of the condensation test apparatus 1 (humidifier for condensation 50). [Explanation of symbols]

[0064] 1. Condensation testing apparatus 12 Examination Rooms 15. Air Conditioning Department 23 Air conditioning equipment 50 Humidifier for condensation 51 Water tank 52 Water supply pump 53a, 53b heat exchanger 55. Water storage container (water storage section) 56 Drain valve 63a, 63b Retaining members 67 Vertical wall 70 Ventilation holes 73. Heater for condensation (heating means) 100 specimen 101 Covering member

Claims

1. A condensation test apparatus comprising a test chamber in which a test specimen is placed, an air conditioning means for adjusting the environment inside the test chamber, a water reservoir located inside the test chamber and supplied with water from outside the test chamber, and a heating means, wherein the heating means heats the water in the water reservoir to create a high-humidity environment inside the test chamber, causing condensation on the test specimen, A condensation test apparatus characterized by having a heat exchanger, the heat exchanger being located in the test chamber, and water passing through the heat exchanger being supplied to the water storage section.

2. The condensation testing apparatus according to claim 1, characterized in that it has a drain valve for discharging water from the water storage section, and the drain valve is opened and closed by an electrical signal.

3. The condensation test apparatus according to claim 1, characterized in that the heat exchanger is a spiral tube.

4. The condensation test apparatus according to claim 1, characterized in that it has a plurality of the heat exchangers.

5. The condensation test apparatus according to claim 1, characterized in that the heat exchanger is located in a position close to the side wall of the test chamber.

6. The condensation testing apparatus according to claim 1, further comprising a holding member for holding the heat exchanger, wherein the holding member is provided with a vent.

7. A condensation test method performed using a condensation test apparatus according to any one of claims 1 to 6, A bleaching process in which the temperature inside the test chamber is adjusted to a constant temperature and the test specimen is exposed to that temperature environment, A condensation generation step is performed by heating the water in the water reservoir with the heating means to gradually increase the humidity in the test chamber and cause condensation to form on the test specimen, A step following the condensation generation step, which includes a temperature reduction step in which the temperature inside the test chamber is lowered by the air conditioning means, A condensation test method characterized by including, in parallel with the bleaching step, a water supply step of supplying water to the water reservoir from outside the test chamber via the heat exchanger.

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