CN109708487A - An online monitoring method for the freezing state of an air-cooled island - Google Patents
An online monitoring method for the freezing state of an air-cooled island Download PDFInfo
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- 238000007710 freezing Methods 0.000 title claims abstract description 61
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 60
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- 238000009423 ventilation Methods 0.000 claims description 20
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- 230000002528 anti-freeze Effects 0.000 abstract description 6
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Abstract
本发明提供一种空冷岛冻结状态在线监测方法，其包括了空冷岛冻结状态监测系统及空冷单元冻结预测方法；其中所述空冷岛冻结状态监测系统的硬件部分包括：汽轮机排汽管道、各空冷单元温度测点系统、监测数据测量装置、数据处理服务器及监测平台；软件部分包括冻结系数、凝结水过冷度的参量实时计算。本发明基于空冷单元的冻结状态在线监测系统，提出基于供需传热平衡的冻结系数计算方法，通过放热侧和吸热侧传热能力的比较，可本质预测换热管束发生冻结的趋势和程度；基于供需传热平衡的冻结系数和基于凝结水过冷度和逆流段真空抽气温度的复合冻结预警系统，有效提高了机组防冻调节的准确性和操作灵活性，保障了机组冬季运行的安全性和高效性。
The invention provides an online monitoring method for the freezing state of an air-cooling island, which includes a monitoring system for the freezing state of an air-cooling island and a freezing prediction method for an air-cooling unit; wherein the hardware part of the freezing state monitoring system for the air-cooling island includes: a steam turbine exhaust pipe, various air-cooling Unit temperature measuring point system, monitoring data measuring device, data processing server and monitoring platform; the software part includes the real-time calculation of parameters of freezing coefficient and condensate subcooling degree. Based on the on-line monitoring system of the freezing state of the air cooling unit, the invention proposes a freezing coefficient calculation method based on the heat transfer balance of supply and demand, and can essentially predict the freezing trend and degree of the heat exchange tube bundle by comparing the heat transfer capacity of the exothermic side and the heat absorbing side. ;The freezing coefficient based on the balance of supply and demand heat transfer and the composite freezing early warning system based on the subcooling degree of condensate and the vacuum extraction temperature of the countercurrent section effectively improve the accuracy and operational flexibility of the unit's antifreeze adjustment, and ensure the safety of the unit's operation in winter. sex and efficiency.
Description
Technical field
The present invention relates to energy source and power technical fields, and in particular to a kind of Air-Cooling Island frozen state on-line monitoring method.
Background technique
Currently, Large Direct-air-cooling generating set is widely used to the northern area of China, direct air cooled condenser is adopted more
Turbine discharge is cooled down with axial flow blower drive environment air.In most of the northern region of China, two season of summer in winter and day
Night air temperature differs greatly, and winter minimum temperature can be down to subzero 40 DEG C.Since many power plant guarantee unit at the beginning of design
Summer is completely sent out, and the film-cooled heat of condenser is chosen very big, this just brings very big challenge to the operation in winter is antifreeze, especially
Unit opens in winter, shut down and when underrun, bank of condenser pipes easily freezes, and seriously affects the safety fortune of unit
Row.
Direct air cooling system equipment is huge, and air-cooled element number is more, structure is complicated, and each air-cooled unit operation is by equipment itself
The influence of structural condition and extraneous factor is significant, and causing each unit operation conditions, there are larger differences.Low temperature condition in winter
Under, it is more in actual operation due to heating power or mass flow discrepancy that a possibility that air cooling tubes condenser occurrence of large-area is freezed is little
Caused by Local cooling tube bank freeze.Existing prediction freezes means and mainly monitors easily jelly spot temperature and cold point temperature difference
Variation.But it often occurs: when existing system temperature instrumentation shows monitoring position temperature anomaly, cooling tube bundle seriously freezes
Knot can not accurately and rapidly provide condenser situation of enduring cold in real time.Moreover, the temperature point of existing direct air cooling system
It is limited, and the arrangement of measuring point is lack of pertinence, and seems unable to do what one wishes to the monitoring of air-cooled unit partial freezings individual in Air-Cooling Island.
Thus, it is necessary to provide a kind of effective Air-Cooling Island frozen state on-line monitoring method, reinforce freezing the real-time of position to easy
Monitoring, and provide corresponding antifreezing measures.
Summary of the invention
Current air cooling tubes condenser winter easily occur tube bank freeze aiming at the problem that, the purpose of the present invention is to provide a kind of skies
Cool island frozen state on-line monitoring technique proposes to conduct heat based on supply and demand using each heat-sink unit in Air-Cooling Island as monitoring object
The freezing fraction calculation method of balance can effectively improve the accuracy and operating flexibility of the antifreeze adjusting of unit.Maintaining unit
Under conditions of air cooling tubes condenser high vacuum, the safety of unit winter operation is improved, is the low back pressure operation of machine unit in winter
Implementation provides technical guarantee.
In order to realize target call described above, freeze the technical solution used in the present invention is: providing a kind of Air-Cooling Island
State on_line monitoring method comprising Air-Cooling Island frozen state monitoring system and air-cooled unit Freezing prediction method；Wherein institute
State Air-Cooling Island frozen state monitoring system hardware components include: turbine discharge pipeline, each air-cooled cell temperature measuring point system,
Monitoring data measuring device, data processing server and monitoring platform；Software section includes freezing fraction, condensate undercooling
Parameter calculates in real time.
Air-cooled heat-sink unit freezing fraction calculation method are as follows:
(1) the real-time Coefficient K of air-cooled unit
Based on air cooling tubes condenser thermic load Dc, (each air-cooled unit thermic load is Dci) and the monitoring of each air-cooled unit operating parameter:
Condensation temperature tc, inlet air temperature ta1, reality required when air-cooled unit steam sufficiently condenses is provided according to heat transfer theory calculating
When Coefficient K.
(2) air-cooled unit air self-heating convective heat-transfer coefficient Kmin
Under the conditions of winter low temperature, reduces rotation speed of fan or air cooling blower fan stalling can reduce the risk that finned tube freezes, but
The generation freezed cannot be avoided completely；Air cooling blower fan stalls, and steam is remained to by low speed coolings gas such as gravity-flow ventilations in condenser
Stream is cooled down, and air self-heating convective heat-transfer coefficient at this time is with KminIt indicates.
Air-Cooling Island heat-sink unit is in Λ type, and the space formed between two Λ type radiating fins isShape, it is believed that air
Temperature change occurs in the middle position of heat-sink unit, then the hot pressing generated by free convection is poor are as follows:
Δ p=(ρ '-ρ ") gh/2
In formula: Δ p is the thrust that current density difference forms that air rises, Pa；ρ ', ρ " are respectively the close of cold air and hot-air
Degree, kg/m3；G is acceleration of gravity, m/s2；What h was surrounded between finned tubeHeight, m.
Under the conditions of gravity-flow ventilation, the drag losses that air flows through air cooling tubes condenser mainly include main body loss and outlet air
Loss.Main body loss be broadly divided into air enter, leave the local losses of finned-tube bundle and flowed between fin along journey hinder
Power loss.When blower full cut-off, the pressure loss should be overcome by the hot pressing difference that air generates, i.e., air-flow be heated and the heat that is formed
Thrust air-flow velocity corresponding when equal with the pressure loss that air-flow flows through heat-exchanging tube bundle is gravity-flow ventilation wind speed.
Since the actuating pressure that gravity-flow ventilation generates is much smaller than force ventilation form, face velocity is lower, will not generally surpass
Cross 1m/s.Correlative study shows when wind speed is between 0.3~0.9m/s, and air leaves the temperature of finned-tube bundle close to wall
Face temperature, the difference between the two are no more than 1 DEG C, i.e. the wall surface temperature that is approximately finned-tube bundle of outlet air temperature under the conditions of gravity-flow ventilation
Degree.The heat transfer of single row of tubes under the conditions of gravity-flow ventilation can be calculated using heat exchanger heat transfer equation and logarithmic mean temperature difference (LMTD) method
COEFFICIENT Kmin。
(3) air-cooled unit freezing fraction
If the heat transfer coefficient of air-cooled unit demand at that time is less than the air self-heating convective heat-transfer coefficient after air cooling blower fan stalling, empty
The cooling capacity of gas supply is stronger, and air-cooled unit has the tendency that freezing.It is as follows that the present invention defines air-cooled unit freezing fraction:
As freezing fraction ZdjWhen > 1, show under current condensing thermic load, the cooling capacity that gravity-flow ventilation provides is excessive, cooling
Tube bank has the tendency that freezing.A possibility that freezing fraction is bigger, and cooling tube bundle freezes is bigger, needs to take at this time antifreeze
Measure: it reduces heat dissipation area, increase condensing thermic load or reversion adverse current blower.
As freezing fraction ZdjWhen=1, air cooling blower fan stalling, air self-heating convective heat transfer and the heat transfer of steam exhaust condensation demand reach
To balance, critical frozen state can be seen as at this time.
As freezing fraction ZdjWhen < 1, illustrate that air natural cooling ability is limited, is insufficient for steam exhaust condensation demand, should throw
Air cooling blower fan is transported, air side exchange capability of heat is improved.
The real-time monitoring of condenser heat-sink unit freezing fraction is to restraining the generation freezed under the conditions of unit winter operation
To effective preventive effect, when freezing fraction is close to critical freezing fraction, i.e. freezing fraction is provided in 0.9~1.1 range
Freeze alarm signal, and provide counter-measure, such as air cooling blower fan reversion starting thermal wind sensor.Each air-cooled list of air cooling tubes condenser
The real-time monitoring of first freezing fraction is realized by factorization.
Air-cooled unit frozen state monitoring system of the invention further includes temperature pre-warning signal, each air-cooled cell temperature measuring point
System is arranged symmetrically on two Λ type tuberculated pipe beams, wherein at the trisection posistion of tuberculated pipe beam at setting
Set up separately and set there are two air exit temp measuring point, is respectively arranged with two wall temperature measurement points at the position close to top and tail end,
The bottom end of tuberculated pipe beam is provided with condensation water temperature measuring point.
Since adverse current tube bank steam flow is smaller, tube bank upper face temperature should be paid close attention to, arranges multiple temperature sensing
Device reinforces the real-time measurement to cooling tube bundle surface temperature, grasps steam distribution and local coagulation's situation in condenser in time.It is logical
The monitoring to adverse current section vacuum suction temperature is crossed, Comprehensive Evaluation counter flow cell freezes situation.When discovery extraction temperature is abnormal or
When tube bank surface temperature in monitoring position is even lower than 0 DEG C lower, regulating measures are taken in time, such as: reducing rotation speed of fan or stop
Only fan operation prevents it from freezing the expansion that appears and develops, for having occurred and that the need freezed reversion blower carries out heating coil defrosting.
When ambient air temperature is very low, counter flow cell blower stops, and fair current unit also starts lockout risk occur.Condensed water mistake
It is cold to spend the heat exchange situation for being able to reflect fair current condenser.Condensation water temperature of this monitoring system to each air-cooled unit two sides heat-exchanging tube bundle
Carry out real time on-line monitoring.When condensate undercooling be more than under 3 DEG C or current operating condition condensate undercooling increase speed it is different
Chang Shi should carry out radix saposhnikoviae to monitoring unit in advance, cover, shut down the antifreezing measures such as blower.
Advance of the invention is, proposes the freezing fraction real-time computing technique based on supply and demand balance heat transfer.It is logical
The heat transfer for comparing that exhaust steam in steam turbine condenses the heat transfer of demand and air is provided from thermal convection is crossed, to the frozen state of each air-cooled unit
It is monitored on-line, the degree that air-cooled condensing unit freezes is judged according to the size of freezing fraction.
Advance of the invention is, gives and is freezed based on condensate undercooling and adverse current section vacuum suction temperature
Pre-warning signal.By on the air-cooled unit two sides condensate undercooling measuring point of increase, fair current unit lower part wall surface temperature, counter flow cell
Portion's vacuum suction temperature and each unit easily freeze the wall surface temperature etc. at position, prediction each air-cooled list under the conditions of extremely low temperature
The heat exchange situation of member.
Compared with prior art, the beneficial effects of the present invention are: the frozen state on-line monitoring system based on air-cooled unit,
It proposes the freezing fraction calculation method based on supply and demand balance heat transfer, by the comparison of cold side and heat absorbing side heat-transfer capability, can this
The trend and degree that matter prediction heat-exchanging tube bundle freezes；Freezing fraction based on supply and demand balance heat transfer and it is based on hot-well depression
Degree and the compound of adverse current section vacuum suction temperature freeze early warning system, effectively increase the accuracy and operation of the antifreeze adjusting of unit
Flexibility has ensured the safety and high efficiency of unit winter operation.
Detailed description of the invention
Fig. 1 is that air cooling tubes condenser frozen state of the present invention monitors system schematic；
Fig. 2 is the air-cooled unit measuring point value arrangement map of the present invention；
Fig. 3 suitable, counter flow cell structural schematic diagram for air cooling tubes condenser；
Fig. 4 is the air-flow flow schematic diagram in air-cooled unit under the conditions of gravity-flow ventilation；
In figure: 1, Air-Cooling Island heat-sink unit；2, air-cooled unit measuring point；3, monitoring data measure acquisition device；4, data processing takes
Business device；5, platform is monitored on-line；6, steam-distributing pipe road；7, fin heat exchange pipe beam 8, steam turbine condensing distribute bobbin carriage；9, air-cooled
Condenser heat-sink unit heat exchanger tube row；10, frequency conversion axial flow fan；11, heat-sink unit condensate water collecting header；12, each column radiates
Unit condensate water collecting general pipeline；13 adverse current heat-sink unit vacuum suction devices.
Specific embodiment
Be further elaborated with reference to the accompanying drawings of the specification to concrete application of the invention: the present invention is suitable for power station direct
Air cooling unit is connect, application is the entire cooling system of Direct Air-cooled Unit, and Air-Cooling Island heat-sink unit 1 includes several heat-exchanging tube bundles
With the frequency conversion axial flow fan 10 to match.
It is as shown in Figure 1 Air-Cooling Island frozen state on-line monitoring system provided by the present invention, wherein being radiated with Air-Cooling Island
Unit is research object, and wherein Air-Cooling Island heat-sink unit is triangular structure, and bottom edge middle position is provided with frequency conversion axis stream wind
Machine, is in addition provided with air-cooled unit measuring point on the both sides both sides Shang Jun, Air-Cooling Island heat-sink unit and monitoring data measure acquisition device 3
Connection, data processing server 4 receives the collected detection data of institute, and is analyzed, by on-line monitoring platform 5 to its into
Row monitoring.As shown in Fig. 2, arranging several measuring points for each air-cooled unit, and it is connected with control room monitoring platform, the fortune of monitoring
Row data include: into condensing flow, condenser main condensing zone the operation vacuum of heat-sink unit, axial flow blower running speed,
Air-cooled unit cooling air out temperature etc..By the real-time calculation and analysis to each unit heat exchange situation, each unit is obtained
Real-time freezing fraction under operating condition.
Air-cooled heat-sink unit freezing fraction calculation method are as follows:
(1) the real-time Coefficient K of air-cooled unit
Based on air cooling tubes condenser thermic load Dc(each air-cooled unit thermic load is Dci) and the monitoring of each air-cooled unit operating parameter: it is cold
Solidifying temperature tc, inlet air temperature ta1, calculated according to heat transfer theory provide it is required real-time when air-cooled unit steam sufficiently condenses
Coefficient K.
(2) air-cooled unit air self-heating convective heat-transfer coefficient Kmin
Under the conditions of winter low temperature, reduces rotation speed of fan or air cooling blower fan stalling can reduce the risk that finned tube freezes, but
The generation freezed cannot be avoided completely.Air cooling blower fan stalls, and steam is remained to by low speed coolings gas such as gravity-flow ventilations in condenser
Stream is cooled down.Air self-heating convective heat-transfer coefficient at this time is with KminIt indicates.
Air-Cooling Island heat-sink unit is in Λ type, and the space formed between two Λ type radiating fins isShape (shown in Fig. 4), recognizes
Occur for the temperature change of air in the middle position of heat-sink unit.The hot pressing then generated by free convection is poor are as follows:
Δ p=(ρ '-ρ ") gh/2
In formula: Δ p is the thrust that current density difference forms that air rises, Pa；ρ ', ρ " are respectively the close of cold air and hot-air
Degree, kg/m3；G is acceleration of gravity, m/s2；What h was surrounded between finned tubeHeight, m.
Under the conditions of gravity-flow ventilation, the drag losses that air flows through air cooling tubes condenser mainly include main body loss and outlet air
Loss.Main body loss be broadly divided into air enter, leave the local losses of finned-tube bundle and flowed between fin along journey hinder
Power loss.When blower full cut-off, the pressure loss should be overcome by the hot pressing difference that air generates, i.e., air-flow be heated and the heat that is formed
Thrust air-flow velocity corresponding when equal with the pressure loss that air-flow flows through heat-exchanging tube bundle is gravity-flow ventilation wind speed.
Since the actuating pressure that gravity-flow ventilation generates is much smaller than force ventilation form, face velocity is lower, will not generally surpass
Cross 1m/s.Correlative study shows when wind speed is between 0.3~0.9m/s, and air leaves the temperature of finned-tube bundle close to wall
Face temperature, the difference between the two do not exceed 1 DEG C.Then the outlet air temperature under the conditions of gravity-flow ventilation is approximately the wall surface of finned-tube bundle
Temperature.The biography of single row of tubes under the conditions of gravity-flow ventilation can be calculated using heat exchanger heat transfer equation and logarithmic mean temperature difference (LMTD) method
Hot COEFFICIENT Kmin。
(3) air-cooled unit freezing fraction
If the heat transfer coefficient of air-cooled unit demand at that time is less than the air self-heating convective heat-transfer coefficient after air cooling blower fan stalling, empty
The cooling capacity of gas supply is stronger, and air-cooled unit has the tendency that freezing.It is as follows that the present invention defines air-cooled unit freezing fraction:
As freezing fraction ZdjWhen > 1, show under current condensing thermic load, the cooling capacity that gravity-flow ventilation provides is excessive, cooling
Tube bank has the tendency that freezing.A possibility that freezing fraction is bigger, and cooling tube bundle freezes is bigger, needs to take at this time antifreeze
Measure: it reduces heat dissipation area, increase condensing thermic load or reversion adverse current blower.
As freezing fraction ZdjWhen=1, air cooling blower fan stalling, air self-heating convective heat transfer and the heat transfer of steam exhaust condensation demand reach
To balance, critical frozen state can be seen as at this time.
As freezing fraction ZdjWhen < 1, illustrate that air natural cooling ability is limited, is insufficient for steam exhaust condensation demand, should throw
Air cooling blower fan is transported, air side exchange capability of heat is improved.
The real-time monitoring of condenser heat-sink unit freezing fraction is to restraining the generation freezed under the conditions of unit winter operation
To effective preventive effect, when freezing fraction is close to critical freezing fraction, i.e. freezing fraction is provided in 0.9~1.1 range
Freeze alarm signal, and provide counter-measure, such as air cooling blower fan reversion starting thermal wind sensor.Each air-cooled list of air cooling tubes condenser
The real-time monitoring of first freezing fraction is realized by factorization.
Air-cooled unit frozen state monitoring system of the invention further includes temperature pre-warning signal, each air-cooled cell temperature measuring point
System arrangement is shown in Fig. 2.
Since adverse current tube bank steam flow is smaller, tube bank upper face temperature should be paid close attention to, arranges multiple temperature sensing
Device reinforces the real-time measurement to cooling tube bundle surface temperature, grasps steam distribution and local coagulation's situation in condenser in time, inverse
Flowing bundle temperature point is referring to Fig. 3.By the monitoring to adverse current section vacuum suction temperature, Comprehensive Evaluation counter flow cell freezes feelings
Condition.When finding that extraction temperature is abnormal or tube bank surface temperature in monitoring position is even lower than 0 DEG C lower, adjustment is taken to arrange in time
It applies, such as: reducing rotation speed of fan or stop fan operation, prevent it from freezing the expansion that appears and develops, freeze for having occurred and that
Blower need to be inverted and carry out heating coil defrosting.
When ambient air temperature is very low, counter flow cell blower stops, and fair current unit also starts lockout risk occur.Condensed water mistake
It is cold to spend the heat exchange situation for being able to reflect fair current condenser.Condensation water temperature of this monitoring system to each air-cooled unit two sides heat-exchanging tube bundle
Carry out real time on-line monitoring.When condensate undercooling be more than under 3 DEG C or current operating condition condensate undercooling increase speed it is different
Chang Shi should carry out radix saposhnikoviae to monitoring unit in advance, cover, shut down the antifreezing measures such as blower.
Claims (3)
1. a kind of Air-Cooling Island frozen state on-line monitoring method comprising Air-Cooling Island frozen state monitoring system and air-cooled unit
Freezing prediction method；Wherein the hardware components of the Air-Cooling Island frozen state monitoring system include: turbine discharge pipeline, each sky
Cold cell temperature measuring point system, monitoring data measuring device, data processing server and monitoring platform；Wherein, air-cooled unit temperature
Degree is surveyed electric system and is set on gas turbine exhaust gas pipeline, air-cooled cell temperature measuring point system, monitoring data measuring device, at data
Reason server and monitoring platform are successively attached；Software section include freezing fraction, condensate undercooling parameter count in real time
It calculates；
Air-cooled heat-sink unit freezing fraction calculation method are as follows:
(1) the real-time Coefficient K of air-cooled unit
Based on air cooling tubes condenser thermic load Dc, (each air-cooled unit thermic load is Dci) and the monitoring of each air-cooled unit operating parameter: it is cold
Solidifying temperature tc, inlet air temperature ta1, calculated according to heat transfer theory provide it is required real-time when air-cooled unit steam sufficiently condenses
Coefficient K；
(2) air-cooled unit air self-heating convective heat-transfer coefficient Kmin
Air cooling blower fan stalls, and steam remains to be cooled down by low speed coolings air-flows such as gravity-flow ventilations in condenser, sky at this time
Gas self-heating convective heat-transfer coefficient indicates with Kmin,
Air-Cooling Island heat-sink unit is in Λ type, and the space formed between two Λ type radiating fins is ▽ shape, it is believed that the temperature of air
Variation occurs in the middle position of heat-sink unit, then the hot pressing generated by free convection is poor are as follows:
Δ p=(ρ '-ρ ") gh/2
In formula: Δ p is the thrust that current density difference forms that air rises, Pa；ρ ', ρ " are respectively the close of cold air and hot-air
Degree, kg/m3；G is acceleration of gravity, m/s2；The height for the ▽ that h is surrounded between finned tube, m；
When blower full cut-off, the pressure loss should be overcome by the hot pressing difference that air generates, i.e., air-flow is heated and what is formed picks power
Corresponding air-flow velocity is gravity-flow ventilation wind speed when equal with the pressure loss that air-flow flows through heat-exchanging tube bundle；It is passed using heat exchanger
The Coefficient K min of single row of tubes under the conditions of gravity-flow ventilation can be calculated in Biot-fourier equation and logarithmic mean temperature difference (LMTD) method；
(3) air-cooled unit freezing fraction
If the heat transfer coefficient of air-cooled unit demand at that time is less than the air self-heating convective heat-transfer coefficient after air cooling blower fan stalling, empty
The cooling capacity of gas supply is stronger, and air-cooled unit has the tendency that freezing.It is as follows that the present invention defines air-cooled unit freezing fraction:
When freezing fraction is close to critical freezing fraction, i.e. freezing fraction provides in 0.9~1.1 range and freezes alarm signal,
And provide counter-measure.
A kind of Air-Cooling Island frozen state on-line monitoring method according to claim 1, it is characterised in that: air-cooled unit freezes
Condition monitoring system further includes temperature pre-warning signal, and each air-cooled cell temperature measuring point system is in two Λ type tuberculated pipe beams
On be arranged symmetrically, wherein at the trisection posistion of tuberculated pipe beam setting punishment setting there are two air exit temp survey
Point is respectively arranged with two wall temperature measurement points at the position close to top and tail end, is provided in the bottom end of tuberculated pipe beam
Condense water temperature measuring point.
2. a kind of Air-Cooling Island frozen state on-line monitoring method according to claim 1, it is characterised in that: the Air-Cooling Island
Frozen state monitors system and carries out real time on-line monitoring to the condensation water temperature of each air-cooled unit two sides heat-exchanging tube bundle.
3. a kind of Air-Cooling Island frozen state on-line monitoring method according to claim 1, it is characterised in that: by comparing vapour
The heat transfer that the heat transfer of turbine steam exhaust condensation demand and air are provided from thermal convection carries out the frozen state of each air-cooled unit online
Monitoring, judges the degree that air-cooled condensing unit freezes according to the size of freezing fraction.
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| CN110542326A (en) * | 2019-09-25 | 2019-12-06 | 双良节能系统股份有限公司 | A direct air-cooled steam system and its control method for extracting non-condensable gas |
| CN111457752A (en) * | 2020-04-02 | 2020-07-28 | 内蒙古锦联铝材有限公司 | Active anti-freezing method for air cooling generator set |
| CN111637762A (en) * | 2020-05-07 | 2020-09-08 | 中国大唐集团科学技术研究院有限公司火力发电技术研究院 | An automatic control method and system for an air-cooled condenser fan |
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| CN111637762A (en) * | 2020-05-07 | 2020-09-08 | 中国大唐集团科学技术研究院有限公司火力发电技术研究院 | An automatic control method and system for an air-cooled condenser fan |
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| CN114861431B (en) * | 2022-04-27 | 2025-07-11 | 西安热工研究院有限公司 | Air cooling island antifreeze area identification method and system |
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| CN118442646B (en) * | 2024-05-17 | 2024-11-15 | 青岛理工大学 | Non-equal-height column arrangement design method and system for coping with air source heat pump cold island effect |
| CN119803723A (en) * | 2024-11-11 | 2025-04-11 | 上海电力大学 | One-dimensional layout method and system of measuring points for antifreeze monitoring of finned tube bundles in direct air-cooling islands |
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