阅读说明：本技术 用于环境测试舱性能检定的温控式气体释放装置 (Temperature control type gas release device for performance verification of environment test chamber ) 是由 蔡广凯 李旻雯 李景广 孙婵娟 于 2020-12-08 设计创作，主要内容包括：本发明公开了一种用于环境测试舱性能测定的温控式气体释放装置,包括水槽和圆筒,水槽有一开口,开口具有凹入水槽槽体内的筒状开口壁,开口壁上设连接内螺纹；圆筒上端为开口端,下端为封闭的筒底；圆筒筒体外壁设有与内螺纹匹配的连接外螺纹,圆筒螺纹固定于筒状开口壁上；圆筒开口端箍有渗透膜；水槽槽壁沿径向设有凸入槽体内的第一管状体,第一管状体的空心腔体连通水槽外并与水槽内相阻隔,第一管状体腔体内安有加热管；第一管状体位于水槽槽底和圆筒筒底间；水槽槽壁上还设有凸入槽体内的第二管状体,第二管状体的空心腔腔体连通水槽外并与水槽内相阻隔,第二管状体腔体内安有温度传感器；第二管状体位于圆筒周缘所对应水槽槽壁上。(The invention discloses a temperature control type gas release device for measuring the performance of an environment test chamber, which comprises a water tank and a cylinder, wherein the water tank is provided with an opening, the opening is provided with a cylindrical opening wall recessed into the tank body of the water tank, and the opening wall is provided with a connecting internal thread; the upper end of the cylinder is an open end, and the lower end of the cylinder is a closed cylinder bottom; the outer wall of the cylindrical barrel body is provided with a connecting external thread matched with the internal thread, and the cylindrical thread is fixed on the wall of the cylindrical opening; the open end of the cylinder is hooped with a permeable membrane; a first tubular body protruding into the trough body is arranged on the wall of the trough along the radial direction, a hollow cavity of the first tubular body is communicated with the outside of the trough and isolated from the inside of the trough, and a heating pipe is arranged in the cavity of the first tubular body; the first tubular body is positioned between the bottom of the water tank and the bottom of the cylinder; a second tubular body protruding into the trough body is further arranged on the wall of the water trough, a hollow cavity of the second tubular body is communicated with the outside of the water trough and is isolated from the inside of the water trough, and a temperature sensor is arranged in the cavity of the second tubular body; the second tubular body is positioned on the wall of the water tank corresponding to the periphery of the cylinder.)

1. A temperature controlled gas release device for performance measurement of an environmental test chamber, comprising:

the upper part of the water tank is provided with an opening, the opening is provided with a cylindrical opening wall which is recessed into the tank body of the water tank, and the opening wall is provided with a connecting internal thread; and

the upper end of the cylinder is an open end, and the lower end of the cylinder is a closed cylinder bottom; the outer wall of the cylinder body of the cylinder is provided with a connecting external thread matched with the connecting internal thread, and the cylinder thread is fixed on the wall of the cylindrical opening through the matching of the connecting external thread and the connecting internal thread; the open end of the cylinder is hooped with a permeable membrane;

more than one first tubular body protruding into the trough body is arranged on the wall of the water trough along the radial direction, the first tubular body is provided with a hollow cavity, the cavity of the first tubular body is communicated with the outside of the water trough and is isolated from the inside of the water trough, and a heating pipe is arranged in the cavity of the first tubular body; the first tubular body is positioned between the bottom of the water tank and the bottom of the cylinder;

the wall of the water tank is also provided with a second tubular body protruding into the tank body, the second tubular body is provided with a hollow cavity, the cavity of the second tubular body is communicated with the outside of the water tank and is isolated from the inside of the water tank, and a temperature sensor is arranged in the cavity of the second tubular body; the second tubular body is positioned on the wall of the water tank corresponding to the periphery of the cylinder.

2. The temperature-controlled gas release device for performance determination of the environmental test chamber according to claim 1, wherein except for the opening, the periphery of the tank body of the water tank is wrapped with an insulating layer.

3. The temperature-controlled gas release device for performance measurement of the environmental test chamber according to claim 1, wherein the wall of the water tank is provided with three first tubular bodies, and the three first tubular bodies are arranged at an included angle of 120 ° in pairs.

4. The temperature-controlled gas release device for performance measurement of the environmental test chamber according to claim 1, wherein the connecting external thread of the cylinder is a first external thread, the open end of the cylinder is provided with a second external thread, and the permeable membrane is hooped on the open surface of the cylinder by a sealing nut matched with the second external thread.

5. The temperature controlled gas release device for environmental test chamber performance measurement according to claim 1, wherein the second tubular body substantially corresponds to a vertical neutral position of the cylinder.

6. The temperature controlled gas release device for performance measurement of an environmental test chamber of claim 1, wherein the base of the water tank is a stainless steel member; the cylinder body of the cylinder is also a stainless steel piece.

7. The temperature controlled gas release device for environmental test chamber performance measurement of claim 1, wherein the heating tube is an electrical heating rod.

8. The temperature controlled gas release device for performance measurement of an environmental test chamber of claim 1 or 7, wherein the heating tube and the temperature sensor are electrically connected to a temperature controller.

9. The temperature-controlled gas release device for performance measurement of an environmental test chamber of claim 1, wherein the permeable membrane is a porous homogeneous membrane that is resistant to high temperature, chemically stable, and corrosion.

Technical Field

The invention belongs to the technical field of indoor environment detection, and particularly relates to a temperature control type gas release device for performance detection of an environment test chamber system.

Background

At present, an environmental chamber test method becomes a mainstream method for testing pollutant emission characteristics at home and abroad. The environmental chamber is widely applied to research and detection of harmful gas release of building decoration materials, interior decoration materials, furniture, electronic products, automotive interior and the like. With the continuous development of the environmental chamber testing technology, an important problem of testing the release amount of the pollution source by the current testing chamber method is the accuracy of the testing result. The accuracy of the test result is also an important basis for researching the indoor VOCs source emission mechanism, human exposure and health risks and engineering control and treatment.

However, on the one hand, the existing gas release devices in the industry and the market are mature in technology and can be directly used, the operation process is complex and inconvenient, and the existing part of the gas release devices cannot simply, conveniently and quickly prepare the test conditions with freely-set stable release rate due to the structural characteristics of the devices, so that the relevant technical standard bars have relevant regulations, but are difficult to operate in practice, and the existing test cabin systems in the market can not be subjected to relevant performance verification, so that the system performance of the environmental test cabin and the accuracy of the tested result are difficult to judge. On the other hand, detection work of pollutants emitted by different types of decoration materials and furniture is often required to be carried out in the same test cabin system, but the release rate ranges of the detection work are different, and release devices with different release rate ranges can be quickly set so as to check and inspect the test accuracy of the environment test cabin system in testing different decoration materials and furniture.

Disclosure of Invention

The invention aims to solve the technical problem that the existing environment test chamber for testing the release rate of VOCs pollutants is not provided with a standard release device, so that the performance verification of the recovery rate and the test accuracy is difficult to carry out, and the system performance and the accuracy of a tested result of the environment test chamber are difficult to judge.

The technical problem to be solved can be implemented by the following technical scheme.

A temperature-controlled gas release device for performance measurement of an environmental test chamber is characterized by comprising:

the upper part of the water tank is provided with an opening, the opening is provided with a cylindrical opening wall which is recessed into the tank body of the water tank, and the opening wall is provided with a connecting internal thread; and

the upper end of the cylinder is an open end, and the lower end of the cylinder is a closed cylinder bottom; the outer wall of the cylinder body of the cylinder is provided with a connecting external thread matched with the connecting internal thread, and the cylinder thread is fixed on the wall of the cylindrical opening through the matching of the connecting external thread and the connecting internal thread; the open end of the cylinder is hooped with a permeable membrane;

more than one first tubular body protruding into the trough body is arranged on the wall of the water trough along the radial direction, the first tubular body is provided with a hollow cavity, the cavity of the first tubular body is communicated with the outside of the water trough and is isolated from the inside of the water trough, and a heating pipe is arranged in the cavity of the first tubular body; the first tubular body is positioned between the bottom of the water tank and the bottom of the cylinder;

the wall of the water tank is also provided with a second tubular body protruding into the tank body, the second tubular body is provided with a hollow cavity, the cavity of the second tubular body is communicated with the outside of the water tank and is isolated from the inside of the water tank, and a temperature sensor is arranged in the cavity of the second tubular body; the second tubular body is positioned on the wall of the water tank corresponding to the periphery of the cylinder.

As a further improvement of the technical scheme, except for the opening, the periphery of the trough body of the water trough is wrapped with a heat-insulating layer.

The improved structure is characterized in that the wall of the water tank is provided with three first tubular bodies, and every two of the three first tubular bodies are arranged at an included angle of 120 degrees.

In a preferred embodiment of the present invention, the connecting external thread of the cylinder is a first external thread, the open end of the cylinder is provided with a second external thread, and the permeable membrane is fastened to the open surface of the cylinder through a seal nut matching with the second external thread.

Also as a preferred embodiment of the invention, said second tubular body substantially corresponds to the vertical middle position of said cylinder.

As a further improvement of the technical scheme, the base body of the water tank is a stainless steel part; the cylinder body of the cylinder is also a stainless steel piece.

Preferably, the heating pipe is an electric heating rod.

As a further improvement of the invention, the heating pipe and the temperature sensor are electrically connected with the temperature controller.

Preferably, the permeable membrane is a porous homogeneous membrane that is resistant to high temperatures, has high chemical stability, and is resistant to corrosion.

The temperature control type gas release device for measuring the performance of the environment test chamber, which adopts the technical scheme, has the following characteristics and effects:

the gas release rate of the invention is that water in a stainless steel water tank is heated by an electric heating rod, and then the target solution in a cylinder is heated by utilizing the water bath heating principle. Furthermore, the set temperature value of the temperature controller can be adjusted, so that the water in the electric heating rod heating water tank reaches the set temperature value. When water is heated, the temperature sensor transmits real-time temperature signals to the temperature controller, the temperature controller controls the solid-state relay to be continuously disconnected and closed, so that the water temperature is kept constant, and then the solution temperature and the water temperature are subjected to heat transmission through a heat conduction principle. When the temperature of the water in the water tank and the temperature of the solution in the cylinder reach heat balance, the temperature of the solution in the cylinder is kept constant. Part of solution in the cylinder is changed from liquid phase to gas phase, the gas phase permeates the permeable membrane again, and the release rate of the gas permeating the permeable membrane is unchanged at the constant temperature, so that the release rate is controlled in such a way. And calculating the gas release rate at different temperatures according to the mass reduction amount before and after the device test. The device can be operated to achieve the purposes of definite, controllable and stable release rate and wide range.

Drawings

FIG. 1 is a schematic structural diagram of a temperature-controlled gas releasing device according to the present invention;

FIG. 2 is a schematic diagram of the position of an electric heating tube;

in the figure: 1-heat insulation material 2-sealing nut 21-internal thread 3-permeable membrane 5-water tank 51-tank wall 52-tank bottom 53-tank opening wall 531-internal thread 54-tank opening 6-sleeve 8-cylinder 81-cylinder wall 811-external thread 82-cylinder bottom 83-cavity 9-sleeve 10-circuit conducting wire 11-temperature controller

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

The invention provides a standard release device for testing pollutant release rate, which can quickly and simply reach different stable gas release rates with wide range by regulation, thereby correspondingly checking and checking the experimental test of an environmental chamber test system and solving the problem of the accuracy of the current environmental test chamber system.

Referring to fig. 1 and 2, the gas release device for testing and detection of the environmental chamber testing system provided by the invention comprises a stainless steel water tank 5, wherein a notch 54 is formed in the upper part of the water tank 5, the notch 54 is provided with a cylindrical notch wall 53 recessed into the interior of the water tank body, and an internal thread 531 is formed on the inner side of the notch wall 53.

A cylinder 8 (which may be understood as a barrel-like structure) of stainless steel is threaded into the internal threads 531 provided in the slot wall 53 by means of external threads 811 on the outside of the wall 81 to locate the cylinder 8 in the slot 54. The cylinder 8 is provided with a cavity 83, the wall of the opening end of the upper part of the cavity is provided with another external thread 812, the permeable membrane 3 (such as a porous uniform membrane with high temperature resistance, stable chemical property and strong corrosion resistance) is pressed and sealed at the opening at the upper end of the cylinder 8 through the matching of the internal thread 21 of the sealing nut 2, the purpose of hooping (fixing) one layer of permeable membrane at the opening end is realized, and then the cavity 83 and the outside are separated, so that the corresponding purpose is realized.

And, a set of three sleeves 9 protruding into the tank body are arranged on the tank wall 51 of the water tank along the radial direction. A sleeve 6 protruding into the tank body is also provided on the tank wall 51 of the sink. The sleeve 9 and the sleeve 6 are structurally communicated with the outside and are isolated from the inside of the groove body; the electric heating rod is built in and fixed in a sleeve 9 inside the stainless steel water tank, and the temperature sensor is built in a micro sleeve 6 inside the stainless steel water tank. Wherein, each sleeve is arranged in the stainless steel water tank and welded into a whole; the sleeve has the function of facilitating replacement of damaged electric heating rods and temperature sensors.

The sleeves 9 of the three electric heating pipes are welded with the stainless steel water tank 5 into a whole, and the sleeves 9 of the electric heating pipes are distributed at intervals in sequence in the horizontal direction, and form an included angle of 120 degrees when being overlooked (as shown in fig. 2, the reference numeral 91 is the central line of the sleeve of the electric heating pipe). The heating rod in the sleeve 9 is connected with a temperature controller 11 through an electrified circuit lead 10, and the temperature sensor in the temperature sensor sleeve 6 is also connected with the temperature controller 11 through the circuit lead 10.

The sleeve 9 is located between the bottom 82 of the cylinder 8 and the bottom 52 of the water tank, and the sleeve 6 protrudes into the tank body from the tank wall 51 corresponding to the approximately vertical middle position of the tank wall 53, which is exactly half the depth of the cylinder 8.

In addition, the heat insulating material 1 is wrapped around the outer side surfaces (including the bottom surface) of the stainless steel water bath except for the notch 54.

The embodiments of the apparatus of the present invention are described in detail below:

the osmotic membrane 3 is tightly connected with the stainless steel cylinder 8 by the sealing nut 2 through screw pressure; the heat insulation material 1 covers the outer surface of the stainless steel water tank 5. The stainless steel cylinder 8 can be rotated by the internal and external screws, i.e., the internal and external threads 531 and 811, and can be closely attached to or detached from the water tub 5.

The working principle of further calculation by adopting the temperature control type gas release device is as follows:

the temperature is an important influence factor for releasing various pollutants from different types of decorative materials and furniture, so that the release rate of the pollutants is mainly controlled by controlling the temperature. The upper part of the device is provided with a sealing nut specially used for fixing the permeable membrane, when the liquid in the device reaches a certain stable temperature through a temperature control system, the liquid surface in the device starts to carry out a physical process of changing liquid phase into gas phase, and then the gas phase is diffused to the outside of the device through the permeable membrane to realize the release of the gas. The strength of the gas permeation through the permeable membrane during this process is its release rate.

The gas permeation process conforms to Fick's gas diffusion law, which consists of the following equations:

wherein p is_satIs the saturated vapor pressure at the inner surface side of the permeation membrane, and R is an ideal gas constant. A is the surface area of the osmotic membrane, L is the thickness of the osmotic membrane, and T is the temperature.

Temperature and gas diffusion coefficient (D)_m) The experimental correlation of (a):

where T is temperature and A, B is the fitting coefficient.

According to the Clausius-Clapeyron correlation, the following relations are provided:

c is a fitting coefficient; Δ H is the heat of molar vaporization (if the range of temperature change is not large, it can be regarded as a constant at steady state).

Substituting the expressions (2) and (3) into the expression (1) can obtain the theoretical correlation (4) of simplified temperature and gas release rate:

of these, M, N is a simplification coefficient.

Therefore, the release rate at the temperature can be obtained by controlling the temperature to be stable, and different release rates can be obtained by adjusting different temperatures, so that the purposes of wide and controllable release rate are achieved.

In addition, at a certain constant heating temperature, the temperature t is constant, and the gas release rate ρ is constant. Thus, when the releasing device is operated under constant temperature conditions, the releasing rate can be determined by weighing the mass reduction of the releasing device by a weighing method in a suitable time interval, i.e., the formula (5):

in the formula ρ: release rate (g/min); w₁: time t₁Mass of the time release device (g); w₂: time t₂The mass (g) of the device is released.

Therefore, the release device can be placed in an environment cabin, and the heating state of the heating rod in the electric heating tube sleeve 9 is adjusted by the temperature controller to carry out water bath heating, so that the temperature of the solution in the release device is controllable, adjustable and constant. The mass reduction of the solution in the test process can be obtained by a weighing method in a period of time, and then the gas release rate of the solution changing from a liquid phase to a gas phase and permeating the permeable membrane can be calculated by the method.

The further working process of the temperature control type gas release device is as follows:

before the power is turned on, the upper part of the stainless steel cylinder 8 is opened by the gland nut 2 and the liquid to be tested is injected therein. After the injection amount reaches a preset value, the permeable membrane 3 is pressed and sealed by the sealing nut 2, and then the total mass of the stainless steel cylinder containing the liquid is weighed to be m₁Then, the stainless steel cylinder 8 is tightly attached to the stainless steel water tank 5 through screw rotation, and the assembled whole set of device is placed in an environmental chamber. The power is switched on, the temperature is set at a certain value by adjusting the temperature controller 11, and the temperature controller 11 outputs a signal to control the solid-state relay, so that the output temperature value of the sensor in the temperature sensor sleeve 6 is equal to the set value. After a period of time Δ t, the environmental hatch is opened, the device is removed, and the stainless steel cylinder 8 is removed by screwing, weighed again and its mass recorded as m₂. The release rate of the gas at different temperatures can thus be calculated from the change in mass of the liquid over a period of time.