CN103033532A - Experimental device for steam condensation heat transfer containing multi-component non-condensable gases - Google Patents

Abstract

The invention provides a steam condensation heat exchange experimental device containing multi-component non-condensable gas. Including steam supply system, air supply system, other gaseous supply system, cooling water system and condensation experimental body, the condensation experimental body includes the casing and sets up the experiment pipe in the casing, the upper portion and the lower part of casing set up last intake pipe and lower intake pipe respectively, last intake pipe and install last intake valve and lower intake valve respectively in the intake pipe down, main line and steam supply system after going up the intake pipe and connecting in parallel with lower intake pipe, air supply system and other gaseous supply system link to each other, the condensate jar is connected to the casing bottom, steam condenses in the condensation experimental body after, the condensate jar is followed the casing bottom and is flowed into the condensate jar downwards and through the drain valve discharge, the upper and lower both ends of experiment pipe link to each other with cooling water system. The invention can carry out the external condensation heat exchange experiment of vertical single tubes and tube bundles with various sizes and structural types, and research the influence mechanism of factors such as steam flow direction, non-condensable gas layer and the like on condensation heat exchange.

Description

Experimental device for steam condensation heat transfer containing multi-component non-condensable gases

technical field

The invention relates to a condensation heat exchange experimental device, in particular to a steam condensation heat exchange experimental device containing multi-component non-condensable gas.

Background technique

As a basic form of heat transfer, steam condensation can obtain a high heat transfer coefficient from a low temperature difference, so it is widely used in many industries such as energy, power, and chemical industry. Enhancing the heat transfer capacity of steam condensation is of great significance to improve the thermal efficiency of heat exchangers. However, non-condensable gases such as air have a strong inhibitory effect on condensation heat transfer. For example, air with a mass fraction of 1% in water vapor can reduce the heat transfer coefficient. 60%, so its quantitative research has been a research hotspot in heat transfer and related fields in recent years. At present, in the field of seawater desalination, the condensation and heat transfer capacity of air-containing steam determines the freshwater yield of dew point evaporation and desalination devices to a certain extent. In the field of power plant operation, research on condensation heat transfer of steam containing non-condensable gases is of great significance to the heat export of nuclear power plants and the safe operation of condensers under accident conditions.

At present, experimental research is an irreplaceable way for steam condensation heat transfer with non-condensable gases, but it mainly focuses on horizontal tube condensation and vertical tube condensation, and there are few studies on vertical tube external condensation, especially in many Components under noncondensable gas and reinforced tube conditions. The experimental device is the hardware facility that must be relied on to obtain reliable data, which requires a steam condensation heat transfer experimental device suitable for condensation outside the vertical tube and containing multi-component non-condensable gases. Among the published condensation experiment devices, the "Comprehensive Experimental Device for Condenser" disclosed in the patent application No. 89201616.7 can only be used for teaching and demonstration experiments of condensation outside the horizontal tube, and cannot meet the accuracy requirements of scientific research experiments. ; The patent application No. 200820155479.6 disclosed in the patent document "single tube in-pipe evaporation and condensation integrated experimental device" can only carry out single-tube in-pipe condensation experiments. They are structurally incapable of carrying out condensation experiments outside vertical tubes, and whether the tubes are arranged horizontally or vertically, and whether the steam condenses inside or outside the tubes, there will be differences in gas mixing, condensate accumulation, etc., and the condensation heat transfer characteristics are also obvious. different. MITDehbi's experimental device (Dehbi. The Effects of Non-condensable Gases on Steam Condensation under Turbulent Natural Convection Conditions, 1991.) Although it can carry out condensation experiments outside the vertical tube, it has the following defects: (1) The steam source is set in the experimental Inside the body, a large water space is required in order to leave a long enough stable time for data measurement, resulting in a large volume of the experimental body, which has high requirements for the experimental site, cylinder strength and sealing; if the experimental body is small , Frequent replenishment of water will cause large fluctuations in the system pressure, greatly shorten the stabilization time, or even fail to stabilize at all, and cannot meet the measurement accuracy requirements. (2) Due to the large density difference of each component of the mixed gas, the opposite steam flow direction will produce a completely different gas mixing effect, which will have a significant impact on the condensation heat transfer. The device cannot change the steam flow direction, and cannot study the steam flow direction on condensation. The effect of heat transfer. (3) The distribution of the non-condensable gas layer near the tube wall is of great value for the analysis of the inhibition mechanism of non-condensable gas on condensation heat transfer. The temperature and concentration parameters inside the gas layer are extremely important data support, but the device does not have No experimental research in this area can be carried out without any measuring device. (4) The steam flow cannot be measured and adjusted, and the heat transfer can only be measured through the cooling water side, and its accuracy cannot be verified by the steam side.

Contents of the invention

The object of the present invention is to provide a steam condensation heat transfer experimental device containing multi-component non-condensable gas that can meet the requirements of various vertical single tubes and tube bundles for external condensation heat transfer experiments.

The purpose of the present invention is achieved like this:

Including steam supply system, air supply system, other gas supply systems, cooling water system and condensation test body, condensation test body includes shell and experimental tube set in the shell, the upper and lower parts of the shell are respectively provided with an upper air inlet pipe and a lower inlet pipe. The air pipe, the upper air intake pipe and the lower air intake pipe are respectively equipped with an upper air intake valve and a lower air intake valve. After the upper air intake pipe and the lower air intake pipe are connected in parallel, the main line is connected with the steam supply system, the air supply system and other gas supply systems. The bottom is connected to the condensate tank. After the steam condenses in the condensation test body, the condensed water flows downward from the bottom of the shell into the condensate tank and is discharged through the drain valve. The upper and lower ends of the test tube are connected to the cooling water system.

The present invention may also include:

1. The steam supply system includes a boiler. The steam generated by the boiler is connected to the main pipeline through a steam delivery pipe. A steam flowmeter is arranged on the steam delivery pipe, and a stop valve is arranged at both ends of the steam flowmeter.

2. The air supply system is mainly composed of an air compressor, an air storage tank, and an oil-gas separator. The air compressor inflates the air storage tank, and the air enters the main line through the oil-air separator. A control system is set between the oil-air separator and the main line. valve.

3. Other gas supply systems are mainly composed of high-pressure gas storage cylinders and pressure reducing valves. The gas is provided by high-pressure gas storage cylinders and enters the main line through the pressure reducing valve.

4. The cooling water system includes a pool, a water pump, a filter, a cooling water flowmeter, and a surge tank. After the water pump draws water from the pool, the cooling water passes through the filter, the cooling water flowmeter, and the surge tank in sequence and enters the lower end of the experimental tube. The cooling water after heat exchange is drawn from the upper end of the experimental tube and returns to the pool through the regulating valve at the outlet, and the flow of cooling water is controlled by the regulating valve.

5. The steam flowmeters are composed of two parallel steam flowmeter groups, and the two ends of the steam flowmeter groups are provided with vertically downward hydrophobic bypasses.

6. A vertically upward exhaust bypass is arranged on the upper intake pipe and the lower intake pipe respectively, and exhaust valves are respectively arranged on each exhaust bypass.

7. A gas component measurement system is provided on the condensation test body. The gas component measurement system is composed of a sampling tube, a serpentine tube, a condensed water tank, a dryer, and a gas purity meter. The nozzles of the sampling tube are distributed along the On multiple sections in the axial direction of the test tube, the mixed gas enters the serpentine tube immersed in the condensate tank from the sampling tube, the steam condenses, the condensate is absorbed by the dryer, and the dry gas enters the gas purity meter.

8. The serpentine tube forms a certain angle with the horizontal plane.

The invention provides an experimental device for studying the condensation heat transfer characteristics of steam containing multi-component non-condensable gases by using single-phase forced circulation of cooling water, which can conduct vertical single-tube and tube-bundle tubes of various sizes and structures. The external condensation heat transfer experiment can study the influence mechanism of steam flow direction, non-condensable gas layer and other factors on condensation heat transfer through experiments, so as to provide reliable technical support for the development of heat exchange elements, optimal design and technical innovation of heat exchangers.

The features of the technical solution of the present invention include:

The steam condensation heat exchange experimental device containing multi-component non-condensable gas of the present invention is mainly composed of a steam supply system, an air supply system, other gas supply systems, a cooling water system, a condensation test body, a measurement system and a data acquisition system. The steam supply system is mainly composed of a boiler and a flowmeter. The steam is generated by the boiler and flows through the steam flowmeter into the main line. The air supply system is mainly composed of an air compressor, an air storage tank, and an oil-air separator. The air compressor inflates the air storage tank, and the air enters the main line through the oil-air separator. Other gas supply systems are mainly composed of high-pressure gas storage cylinders and pressure reducing valves. The gas is provided by high-pressure gas storage cylinders and enters the main line through the pressure reducing valve. After each gas supply pipeline merges into the main pipeline, the main pipeline is divided into two inlet pipelines, which lead to the upper and lower parts of the shell side of the condensation test body through the upper inlet valve and the lower inlet valve respectively. After the steam condenses in the condensation test body, the condensed water flows downward from the bottom of the test body into the condensate tank, and finally is discharged through the drain valve. In the cooling water system, after the water pump draws water from the pool, the cooling water enters the test tube through the filter, flow meter and surge tank in turn, and returns to the pool through the regulating valve at the outlet after exchanging heat in the tube. control.

The flow measurement of steam and cooling water adopts the flowmeter group, the number of flowmeters in the flowmeter group is determined according to the needs of the experiment, and the measuring ranges are connected from small to large to cover the required flow range. According to the predetermined flow rate, flow meters with different ranges can be matched to ensure the accuracy of steam and cooling water flow measurement.

Both ends of the steam flowmeter group are provided with vertically downward hydrophobic bypasses to discharge the accumulated water generated by the heat dissipation of the pipes before and after the flowmeter, so as to prevent the two-phase fluid from interfering with the flow measurement and causing the system pressure to be unstable.

The two-way intake pipeline uses the upper and lower intake valves to change the steam flow direction, so as to compare the influence of different steam flow directions on the condensation heat transfer, and can promote the uniform mixing of gases and effectively prevent gas stratification. The intake pipeline is also provided with a vertical upward exhaust bypass, and the exhaust valve is used to exhaust and change the gas composition.

A condensate tank is installed under the condensation test body to prevent the condensate from re-evaporating and affecting the experimental measurement. A water level gauge is installed outside to monitor the water level, and when the water level exceeds the predetermined level, the drain valve is opened to discharge the condensed water. In order to prevent cavitation damage to the drain valve when draining condensate, and condensate leakage will affect the heat transfer measurement and comparison, two drain valves, inner and outer, are set here.

The pressure measurement system consists of instruments for measuring the following pressures: the gas pressure of the condensing test body, the steam pressure at the steam flow meter, the pressure of the cooling water at the outlet of the test tube and at the surge tank. At measuring points that require high measurement and adjustment accuracy, multiple pressure transmitters and pressure gauges can be installed for comparison to improve measurement accuracy and adjustability.

The gas composition measurement system consists of sampling tube, serpentine tube, condensate tank, dryer, and gas purity meter. Each gas except steam and air needs to be equipped with a corresponding gas purity meter. The orifice of the sampling tube is distributed on multiple sections along the axial direction of the test tube, the gas enters the purity meter along the sampling tube, and the average value of each section is taken as the result. For the purity instrument that can only measure dry gas components, the mixed gas enters the serpentine tube immersed in the condensate tank from the sampling tube, the steam condenses, the condensate is absorbed by the dryer, and the dry gas enters the gas purity instrument. The serpentine tube forms a certain angle with the horizontal plane, which is good for water drainage, prevents condensation from blocking the tube, and reduces the accuracy of the measurement results.

Except for the readings of the pressure gauge, the water level gauge of the condensate tank and the gas purity meter, the other temperature, flow and pressure data are input into the PC by the data acquisition system, and the software is used to collect, calculate and display the experimental data to realize the control of the experimental work. Real-time monitoring of the situation, and at the same time, all data can be saved, processed, and printed for later in-depth research.

According to the above temperature, pressure, flow and water level data, using the data acquisition system, the heat transfer can be calculated from the cooling water side, steam side and condensate side respectively and monitored in real time, and the accuracy of the measurement system can be verified by comparing the calculation results of the three methods sex.

According to the mixed gas pressure, mainstream temperature, and gas purity meter readings, the proportion of each component gas in the experimental body can be directly calculated without measuring the discharge flow and components. It not only makes the gas composition calculation faster and easier, but also can monitor the current mixed gas composition in real time, improving the operability of composition control during the experiment. The calculation process is as follows:

In the mixed gas, the steam is saturated under its partial pressure, the steady-state temperature of the mixed gas is the steam saturation temperature t _s , and the corresponding steam partial pressure p _s(t) can be found.

According to Agmat's law of partial volume and Dalton's law of partial pressure, the vapor volume fraction

空气体积分数The purity meter reading of a gas is the volume fraction of the constituent gas

air volume fraction

partial pressure of other gases

The mass fraction of a constituent gas

${\mathrm{<span\; class="notranslate">\; \&omega;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;m</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}$

混合气体主流平均温度，由气体主流各截面的热电偶测温求均值。

The average temperature of the main flow of the mixed gas is calculated by the temperature measurement of the thermocouples in each section of the main flow of the gas.

p: The total pressure of the mixed gas, measured by the pressure gauge of the condensing test body.

M _i : the molar mass of the constituent gases, calculated as 18g/mol for steam and 29g/mol for air.

For a purity meter that can only measure dry gas components, the reading of the purity meter after dehumidification is

partial pressure of other gases

air partial pressure

Then the volume fraction of a constituent gas

The steam condensation heat exchange experimental device containing multi-component non-condensable gas has energy conservation at the experimental tube, that is, the heat released by the gas on the shell side

$\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; k</span>}{\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}}_{<span\; class="notranslate">\; \&infin;</span>}<span\; class="notranslate">\; -</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}}_{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; )</span>$

Heat absorption of cooling water on tube side

Q＝M _f (h _fo -h _fi )

Condensation heat transfer coefficient

$\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; fo</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; the\; fi</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}}_{<span\; class="notranslate">\; \&infin;</span>}<span\; class="notranslate">\; -</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}}_{\mathrm{<span\; class="notranslate">\; the\; w</span>}}<span\; class="notranslate">\; )</span>}$

A _o : The external area of the condensation section of the test tube, calculated from the design size. The temperature of the outer wall surface of the condensation section is calculated by the temperature measurement of the thermocouples in each section of the outer wall surface to obtain the average value.

M _f : Cooling water mass flow rate, measured by a cooling water flow meter.

h _fi : The inlet enthalpy of cooling water, which is obtained by looking up the pressure of cooling water at the surge tank and the inlet temperature.

h _fo : Cooling water outlet enthalpy, obtained from the cooling water outlet pressure and temperature look-up table.

The beneficial effects of the present invention are: using single-phase forced circulation of cooling water, under the condition of multi-component non-condensable gas, the experimental research on the condensation heat transfer characteristics outside the steam tube is carried out on the vertical single tube and the tube bundle, which is the first step in condensation heat transfer. An important experimental device for component development, optimal design and technological innovation of heat exchangers. The device can realize: (1) conduct external condensation heat transfer experiments of vertical single tubes and tube bundles of different sizes and structural types, and conduct research on local condensation heat transfer at different positions; (2) change the steam flow direction, compare Effects of different steam flow directions on condensation heat transfer; (3) Real-time monitoring of experimental data, continuous measurement and monitoring of gas components according to steady-state parameters; (4) Simulating the actual condensation environment to compare the effects of different gases on condensation heat transfer; (5) The cooling water flow rate can be adjusted accurately in a wide range to ensure that the temperature rise meets the experimental measurement requirements.

Description of drawings

Accompanying drawing is the schematic flow chart of the present invention.

Detailed ways

Below in conjunction with accompanying drawing, the present invention is described in further detail:

It is mainly composed of steam supply system, air supply system, other gas supply system, cooling water system, condensation experiment body 1, measurement system and data acquisition system. The steam supply system is mainly composed of a boiler 2 and a flow meter 3. The steam is generated by the boiler 2 and flows through the steam flow meter 3 to enter the main line. The air supply system is mainly composed of an air compressor 5, an air storage tank 6, and an oil-air separator 7. The air compressor 5 inflates the air storage tank 6, and the air enters the main line through the oil-air separator 7. Other gas supply systems are mainly composed of a high-pressure gas storage cylinder 8 and a pressure reducing valve 9. The gas is provided by the high-pressure gas storage cylinder 8 and enters the main line through the pressure reducing valve 9. After each gas supply pipeline merges into the main pipeline, the main pipeline is divided into two inlet pipelines, which respectively pass through the upper inlet valve 10 and the lower inlet valve 11 to the upper and lower parts of the shell side of the condensation experiment body 1 . After the steam condenses in the condensation test body 1, the condensed water flows downward from the bottom of the test body 1 into the condensate tank 14, and finally is discharged through the drain valves 15 and 16. In the cooling water system, after the water pump 18 pumps water from the pool 17, the cooling water enters the test tube through the filter 19, the flow meter 20, and the surge tank 21 in turn, and returns to the pool 17 through the regulating valve 23 at the outlet after exchanging heat in the tube. Control valve 23.

Both flowmeter groups 3 and 20 are used for the flow measurement of steam and cooling water. The number of flowmeters in the flowmeter group is determined according to the needs of the experiment, and the measuring ranges are connected from small to large to cover the required flow range. According to the predetermined flow rate, flow meters with different ranges can be matched to ensure the accuracy of steam and cooling water flow measurement.

Both ends of the steam flow meter group 3 are provided with vertically downward hydrophobic bypasses to discharge the accumulated water generated by the heat dissipation of the pipes before and after the flow meter 3, so as to prevent the two-phase fluid from interfering with the flow measurement and causing the system pressure to be unstable.

The two-way intake pipeline uses the upper intake valve 10 and the lower intake valve 11 to change the steam flow direction, so as to compare the influence of different steam flow directions on condensation heat transfer, and can promote uniform gas mixing and effectively prevent gas stratification. The intake pipeline is also respectively provided with a vertically upward exhaust bypass, and exhaust valves 12, 13 are used to exhaust and change the gas composition.

A condensate tank 14 is installed under the condensation test body 1 to prevent the accumulated condensed water from re-evaporating and affecting the experimental measurement. Its exterior is equipped with a water level gauge to monitor the water level, and when the predetermined water level is exceeded, drain valves 15 and 16 are opened to discharge condensed water. In order to prevent cavitation damage to the drain valve when draining condensate, and condensate leakage will affect the heat transfer measurement and comparison, two drain valves, inner and outer, are set here.

The temperature measurement system consists of thermocouples that measure the temperature of the following places: the temperature of the steam at the outlet of the flowmeter 3 and the inlet of the condensation test body 1, the temperature of the main flow of the mixed gas and the temperature near the pipe wall, the temperature of the cooling water inlet and outlet, the temperature of the experimental The tube 22 outer wall surface temperature strengthening tube refers to the outer wall temperature of the base tube and the condensation water temperature of the condensate tank 14 .

The pressure measurement system consists of instruments measuring the following pressures: the gas pressure of the condensing test body 1, the steam pressure at the steam flow meter 3, the pressure of the cooling water at the outlet of the test pipe 22 and the pressure at the surge tank 21. At measuring points that require high measurement and adjustment accuracy, pressure transmitters and pressure gauges can be installed for mutual comparison to improve measurement accuracy and adjustability.

The gas composition measurement system consists of a sampling tube 24, a serpentine tube 25, a condensed water tank 26, a dryer 27, and a gas purity meter 28. Each gas except steam and air needs to be equipped with a corresponding gas purity meter 28. The mouth of the sampling tube 24 is distributed on multiple sections along the axial direction of the test tube 22, the gas enters the purity meter 28 along the sampling tube 24, and the average value of each section is taken as the result. For the purity meter 28 that can only measure dry gas components, the mixed gas enters the serpentine pipe 25 immersed in the condensed water tank 26 from the sampling pipe 24, the steam condenses, the condensed water is absorbed by the dryer 27, and the dry gas enters the gas purity meter 28. The serpentine tube 25 forms a certain angle with the horizontal plane, which is beneficial to water drainage, prevents condensation from blocking the pipeline, and reduces the accuracy of measurement results.

Except the readings of the pressure gauge, the water level gauge of the condensate tank 14 and the gas purity meter 28, the other temperature, flow and pressure data are all input into the PC by the data acquisition system, and the specially compiled software is used for collection, calculation and display, so as to realize the experiment Real-time monitoring of working conditions, and at the same time, all data can be saved, processed, and printed for later in-depth research.

According to the above temperature, pressure, flow and water level data, the heat transfer can be calculated from the cooling water side, steam side and condensate side respectively and monitored in real time, and the accuracy of the measurement system can be verified by comparing the calculation results of the three methods.

According to the mixed gas pressure, mainstream temperature, and gas purity meter 28 indications, the proportion of the constituent gas can be directly calculated, which not only makes the calculation of the gas composition easier, but also enables real-time monitoring of the current mixed gas composition, improving the composition of the experiment. operability of control.

For the pure steam condensation heat exchange experiment, the technical solution 1 is: on the cooling water side, start the water pump 18 to draw water from the pool 17, and the cooling water passes through the filter 19, the flow meter 20, the surge tank 21 and then enters the experimental pipe 22. After heat exchange in the tube, it returns to the pool 17 through the regulating valve 23 at the outlet, and the flow is regulated by the regulating valve 23 . On the steam side, start the boiler 2, wait for its pressure to rise to about 0.03MPa, open the steam valve, the upper intake valve 10 and the drain valve 15, 16, the steam enters the condensation test body 1 and the condensate tank 14 through the flow meter 3, and finally Drain, gradually drain the air in the condensation test body 1 and the condensate tank 14. After half an hour, close the drain valves 15 and 16, increase the boiler pressure and the cooling water flow to a predetermined value, and after the steam condenses on the surface of the condensation section of the test tube 22, the condensed water flows into the condensate tank 14. When the condensed water level exceeds the predetermined water level, first fully open the inner drain valve 15, and then open the outer drain valve 16 to start draining; cavitation.

It is used for steam condensation heat exchange experiments containing air, and its technical scheme 2 is: in order to prevent gas stratification, firstly, air is introduced into the condensation experiment body 1 through the upper air intake pipeline, and then steam is introduced through the lower air intake pipeline. The cooling water circulation is the same as the technical scheme 1. On the air side, start the air compressor 5 to inflate the air storage tank 6 to increase the pressure, and turn off the air compressor 5 after reaching a certain pressure. After the air valve is opened, the air enters the condensation experiment body 1 through the oil-gas separator 7 and the upper air intake valve 10, and closes the air valve and the upper air intake valve 10 after reaching a predetermined pressure. On the steam side, start the boiler 2, and when the pressure rises to a predetermined value, open the lower intake valve 11 and the steam valve in turn, the steam enters the condensation test body 1 through the flow meter 3, and after condensing on the outer wall of the condensation section, the condensed water flows into the condensation chamber. Liquid tank 14, discharge condensed water is the same as technical scheme 1.

This device changes the gas composition by means of exhaust. Open the upper exhaust valve 12 to exhaust, and close the upper exhaust valve 12 when the gas temperature is about to rise to the predetermined temperature of the next working condition. After the pressure and temperature of the mixed gas are stable, judge whether the experimental requirements are met according to the steady state parameters of the system.

It is used for steam condensation heat transfer experiments containing air and helium, and its technical scheme 3 is: in order to prevent gas stratification, the air is first introduced into the condensation experiment body 1 from the upper intake pipeline, and then sequentially introduced from the lower intake pipeline. Helium and steam. The cooling water circulation is the same as the technical scheme 1, and the air side operation is the same as the technical scheme 2. On the helium gas side, open the lower intake valve 11, adjust the pressure reducing valve 9, the helium gas directly enters the condensation test body 1 from the high-pressure gas storage cylinder 8, and close the pressure reducing valve 9 after reaching the predetermined pressure. The steam side operation and exhaust change components are the same as the technical scheme 2.

In the helium gas measurement system, open the valve of any cross-section sampling pipe 24, the mixed gas enters the serpentine pipe 25 immersed in the condensed water tank 26 along the sampling pipe 24, the steam condenses, and the condensed water enters the dryer 27 to be absorbed, and the gas is dried Enter the helium purity meter 28 to measure, and get the average value of the measurement results of each section as the result.

Claims (9)

1. the steam-condensation local heat transfer device that contains the polycomponent fouling gas, comprise steam supply system, air supply system, other gas supply system, the cooling water system condensation test body of unifying, it is characterized in that: the condensation test body comprises housing and is arranged at the interior experiment tube of housing, the top of housing and bottom arrange respectively enterprising tracheae and lower inlet duct, be separately installed with upper inlet valve and lower inlet valve on enterprising tracheae and the lower inlet duct, enterprising tracheae and Trunk Line and steam supply system after lower inlet duct is in parallel, air supply system links to each other with other gas supply system, housing bottom connects the lime set tank, after steam condenses in the condensation test body, solidifying water flows into the lime set tank downwards from housing bottom and discharges through draining valve, and the up and down two ends of experiment tube link to each other with cooling water system.

2. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 1, it is characterized in that: described steam supply system comprises boiler, the steam that is produced by boiler connects Trunk Line through steam pipeline, steam-flow meter is set on the steam pipeline, and the two ends of steam-flow meter arrange stop valve.

3. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 2, it is characterized in that: described air supply system mainly is comprised of air compressor machine, gas-holder, oil-gas separator, air compressor machine is inflated to gas-holder, air enters Trunk Line through oil-gas separator, between oil-gas separator and the Trunk Line operation valve is set.

4. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 3, it is characterized in that: other gas supply system mainly is comprised of high-pressure gas cylinder and reduction valve, gas is provided by high-pressure gas cylinder, enters Trunk Line through reduction valve.

5. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 4, it is characterized in that: cooling water system comprises pond, water pump, filtrator, cooling water flow meter, buffer tank, water pump is behind pool water-pumping, chilled water enters the experiment tube lower end through filtrator, cooling water flow meter, buffer tank successively, chilled water behind intraductal heat exchange is drawn through the exit variable valve from the experiment tube upper end and is returned the pond, and cooling water flow is controlled by variable valve.

6. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 5, it is characterized in that: described steam flow is counted two composition steam-flow meter groups arranged side by side, and the two ends of steam-flow meter group all are provided with drain by-pass straight down.

7. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 6 is characterized in that: a discharge bypass straight up respectively is set on enterprising tracheae and the lower inlet duct, is respectively arranged with vent valve on each discharge bypass.

8. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 7, it is characterized in that: be provided with the gas composition measuring system on the condensation test body, described gas composition measuring system is comprised of stopple coupon, coiled pipe, condensation water tank, exsiccator, gas purity instrument, the mouth of pipe of described stopple coupon is distributed in along on the axial a plurality of cross sections of experiment tube, mixed gas is entered the coiled pipe that is immersed in condensation water tank by stopple coupon, steam condensation, the solidifying water device that is dried absorbs, and dry gas enters the gas purity instrument.

9. the steam-condensation local heat transfer device that contains the polycomponent fouling gas according to claim 8, it is characterized in that: described coiled pipe is horizontal by certain angle.

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