JPH0684943B2 - Method for measuring the rate of freezing in the ice storage tank - Google Patents
Method for measuring the rate of freezing in the ice storage tankInfo
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- JPH0684943B2 JPH0684943B2 JP62027177A JP2717787A JPH0684943B2 JP H0684943 B2 JPH0684943 B2 JP H0684943B2 JP 62027177 A JP62027177 A JP 62027177A JP 2717787 A JP2717787 A JP 2717787A JP H0684943 B2 JPH0684943 B2 JP H0684943B2
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- ice
- storage tank
- freezing
- freezing rate
- rate
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Description
【発明の詳細な説明】 ［産業上の利用分野］ この発明は、ビル，家屋等の空調用又は冷凍倉庫等の冷
熱源貯蔵用等に用いられる氷蓄熱槽において、その氷の
結氷率を求めるための測定方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention seeks a freezing rate of ice in an ice heat storage tank used for air conditioning of buildings, houses, etc., or for storage of cold heat sources such as frozen warehouses, etc. It relates to a measurement method for.
［従来の技術］ 従来、氷の結氷率を求める方法に関するものとしては、
次のようなものがある。[Prior Art] Conventionally, as a method for obtaining a freezing rate of ice,
There are the following.
即ち、1986年６月発行「空気調和と冷凍」第55頁には、
従来から開発された結氷率センサーがまとめられてい
る。即ち、 １）接触式（機械式） 第５図は、接触式（機械式）センサーの説明図である。That is, on page 55 of "Air Conditioning and Refrigeration" issued in June 1986,
A collection of conventionally developed freezing rate sensors. That is, 1) Contact type (mechanical type) FIG. 5 is an explanatory view of a contact type (mechanical type) sensor.
この方法は、第５図に示す如く、一定時間毎に検出針11
を駆動制御信号並びに出力信号により駆動部12を回転せ
しめ、これにより駆動部12を回転させて伝熱管の周りの
氷の表面を検出する方法である。As shown in FIG. 5, this method uses the detection needle 11 at regular intervals.
Is a method of rotating the drive unit 12 by the drive control signal and the output signal, and thereby rotating the drive unit 12 to detect the surface of the ice around the heat transfer tube.
２）電極式（１極式） 第６図は、電極式によるセンサーの説明図である。2) Electrode type (1 pole type) FIG. 6 is an explanatory view of an electrode type sensor.
この方法は、第６図に示す如く、液部に設けられた電極
13と冷却管２との間の電位差が氷14の厚さによって変化
することを利用した方法である。This method, as shown in FIG. 6, is an electrode provided in the liquid section.
This is a method that utilizes the fact that the potential difference between the cooling pipe 2 and the cooling pipe 13 changes depending on the thickness of the ice 14.
３）ダイヤフラム式（機械式） 第７図は、ダイヤフラム式（機械式）によるセンサーの
説明図である。3) Diaphragm type (mechanical type) FIG. 7 is an explanatory diagram of a diaphragm type (mechanical type) sensor.
この方法は、第７図に示す如く、冷却管２から一定距離
離れた液中に、マイクロスイッチセンサー15のon/off接
点を設置し、氷14が成長し、マイクロスイッチ15まで到
達すると、マイクロスイッチ15内部の水が氷14となって
膨脹し、接点の端子を作動させ結氷状態を知る方法であ
る。In this method, as shown in FIG. 7, the on / off contact of the micro switch sensor 15 is installed in the liquid at a certain distance from the cooling pipe 2, and when the ice 14 grows and reaches the micro switch 15, the micro switch 15 This is a method in which the water inside the switch 15 expands into ice 14 and expands, and the terminals of the contacts are actuated to know the freezing condition.
４）水位差式（電極式） 第８図は、水位差式（電極式）によるセンサーの説明図
である。4) Water Level Difference Type (Electrode Type) FIG. 8 is an explanatory diagram of a sensor based on the water level difference type (electrode type).
この方法は、第８図に示す如く、氷が凍ると体積は膨脹
し、槽内の水の液面は結氷率が高まるに従い上昇する。
高さ方向に設置された複数個の電極13が水中に入ってい
くときの通電を検知して結氷率を計る方法である。In this method, as shown in FIG. 8, when ice freezes, the volume expands, and the liquid level in the tank rises as the freezing rate increases.
This is a method of measuring the rate of icing by detecting the current flow when a plurality of electrodes 13 installed in the height direction enter the water.
５）水位差式（差圧式） 第９図は、水位差式（電極式）によるセンサーの説明図
である。5) Water Level Difference Type (Differential Pressure Type) FIG. 9 is an explanatory diagram of a sensor based on the water level difference type (electrode type).
この方法は、第９図に示す如く、結氷率の上昇に伴う水
位の上昇を差圧計16で計り結氷率を測定する方法であ
る。As shown in FIG. 9, this method is a method of measuring the rise of the water level accompanying the rise of the freezing rate with a differential pressure gauge 16 to measure the freezing rate.
これら従来方法のうち、本発明方法が適用可能なシステ
ムとして、空調用の氷蓄熱槽をとりあげ、その構造と運
転方法について簡単に説明する。Among these conventional methods, an ice storage tank for air conditioning is taken up as a system to which the method of the present invention can be applied, and its structure and operating method will be briefly described.
第10図は、その構造と運転方法の説明図である。図にお
いて、1:氷蓄熱槽,2:冷却管,3:循環ポンプ,4:熱交換器
である。FIG. 10 is an explanatory diagram of its structure and operating method. In the figure, 1: ice heat storage tank, 2: cooling pipe, 3: circulation pump, 4: heat exchanger.
第10図の様に、氷蓄熱槽１内には、水平多段屈曲管を冷
却管２として設置し、夜間は、この中をヒートポンプの
冷媒（フロンなど）を流し、冷却管２の表面に同心円状
の氷14を成長させていく。As shown in FIG. 10, a horizontal multi-stage bent pipe is installed as a cooling pipe 2 in the ice heat storage tank 1, and at night, a refrigerant of a heat pump (such as chlorofluorocarbon) is flown through it to form concentric circles on the surface of the cooling pipe 2. Grow ice 14 in a shape.
一方、間は、氷蓄熱槽１内の冷水を循環ポンプ３を介し
て、外部に取出し、外部に設けられた熱交換器４によっ
て負荷側の水を冷却し、再び氷蓄熱槽１に戻される。On the other hand, during the period, the cold water in the ice heat storage tank 1 is taken out through the circulation pump 3, the load side water is cooled by the heat exchanger 4 provided outside, and is returned to the ice heat storage tank 1 again. .
以上は、最も一般的と思われる氷蓄熱槽の構造と運転方
法である。The above is the structure and operation method of the ice storage tank that seems to be the most common.
この氷蓄熱槽１は、計画的な蓄熱量を管理するため、及
び完全結氷による容器の破損を防ぐため、常に結氷率を
管理しながら運転する必要がある。The ice heat storage tank 1 needs to be operated while always controlling the freezing rate in order to manage the planned amount of heat storage and prevent damage to the container due to complete freezing.
これ等、問題点について述べると次の通りである。The problems are described below.
（１）従来開発されているセンサーの中で、前述の１）
接触式（機械式）,2）電極式,3）ダイヤフラム式等は、
すべて槽内の局所の氷14の厚さを計測するもので、氷蓄
熱槽１全体の結氷率を計らうとする場合は、同じものを
槽内に多数個設置し、その平均値をとる必要がある。(1) Among the previously developed sensors, the above 1)
Contact type (mechanical type), 2) electrode type, 3) diaphragm type, etc.
All measures the thickness of the local ice 14 in the tank. If you want to measure the freezing rate of the ice storage tank 1 as a whole, it is necessary to install many same things in the tank and take the average value. is there.
（２）１）接触式（機械式）,3）ダイヤフラム式,4）水
位差式等は、時間的に連続して結氷率を計測しようとす
るとき困難が生ずる。(2) 1) Contact type (mechanical type), 3) Diaphragm type, 4) Water level difference type, etc. have difficulty in continuously measuring the freezing rate.
例えば、１）の接触式の場合は頻繁に検出針をまわす必
要があり、又３）ダイヤフラム式では、冷却管２からの
距離を変えた位置に多数個のスイッチを設ける必要があ
り、更に４）水位差式においても同様に高さ方向に多数
個の電極13を設ける必要がある。For example, in the case of 1) the contact type, it is necessary to frequently rotate the detection needle, and in the 3) diaphragm type, it is necessary to provide a large number of switches at positions where the distance from the cooling pipe 2 is changed. ) Also in the water level difference formula, it is necessary to similarly provide a large number of electrodes 13 in the height direction.
（３）５）の水位差式（差圧計式）は全体的な結氷率を
連続的に計ることが出来るが、通常の氷蓄熱槽１は設置
場所の制限から横長の設計となり、凍結に伴う液位変化
は微少で、これを精度よく計測するには可なり高価な差
圧変換器を必要とする。(3) The water level difference method (differential pressure gauge method) of 5) can measure the overall freezing rate continuously, but the normal ice heat storage tank 1 has a horizontally long design due to the limitation of the installation location, and is accompanied by freezing. The change in liquid level is very small, and a very expensive differential pressure converter is required to measure this accurately.
また結氷率が上がった場合には、差圧取出し口が氷14で
閉塞することがある。Further, when the freezing rate increases, the differential pressure outlet may be blocked with ice 14.
更に、この方向は、氷蓄熱槽１の形状が、縦方向に同一
断面積を有してないと、結氷率と水位変化が直線的な関
係とならず、補正が面倒である。Further, in this direction, if the shape of the ice heat storage tank 1 does not have the same cross-sectional area in the vertical direction, the freezing rate and the change in water level do not have a linear relationship, and correction is troublesome.
本発明は、以上の如き従来技術の問題点を解決すること
を目的とするものである。The present invention is intended to solve the problems of the conventional techniques as described above.
［問題点を解決するための手段］ 本発明は、凍結開始前の氷蓄熱槽内の水に所定濃度の電
解質を溶解させておき、凍結進行中に氷蓄熱槽内の液相
部の電気伝導度を測定して、予め求めておいた結氷率と
前記電気伝導度との関係を用いて、氷蓄熱槽内の結氷率
を求めことを特徴とする氷蓄熱槽内の結氷率の測定方法
である。[Means for Solving Problems] In the present invention, an electrolyte having a predetermined concentration is dissolved in water in the ice storage tank before the start of freezing, and electric conduction of a liquid phase portion in the ice storage tank is performed during freezing. By measuring the degree of freezing and using the relationship between the previously determined freezing rate and the electrical conductivity, the freezing rate in the ice storage tank is determined by a method for measuring the freezing rate in the ice storage tank. is there.
［作用］ 本発明は、次の如き構成から成るものである。[Operation] The present invention has the following configuration.
氷蓄熱槽内の水に予め少量の電解質を溶かしておく。A small amount of electrolyte is previously dissolved in water in the ice storage tank.
結氷中の槽内の水を小形ポンプにより連続的にサンプ
リングし、その液の電気伝導率（ｍΩ−１/cm）を計測
する。Water in the freezing tank is continuously sampled by a small pump, and the electric conductivity (mΩ −1 / cm) of the liquid is measured.
この電気伝導率は前記した如く、結氷率の上昇に伴い大
きくなるので、予め検定した結氷率αと電気伝導率との
関係から結氷率αを逆算し求めるものである。Since the electric conductivity increases as the freezing rate rises as described above, the freezing rate α is calculated back from the previously verified relationship between the freezing rate α and the electric conductivity.
本発明の作用について、第11図及び第12図の概念的に示
した説明図により述べれば、 冷却管２の周りに氷14が成長する場合、水中に溶けてい
た他の成分は固相（氷）の外側（液）に排除される性質
がある。The operation of the present invention will be described with reference to the conceptual illustrations shown in FIGS. 11 and 12. When ice 14 grows around the cooling pipe 2, other components dissolved in water are solid phase ( It has the property of being removed to the outside (liquid) of ice.
この状況は、第11図のように、結氷していないときの槽
内は、一様濃度の液となっているが、氷14がついている
ときは氷内は殆ど水の分子で構成され、外側の液は溶質
が氷の成長に伴い濃縮されて濃い液となっていく。In this situation, as shown in Fig. 11, the inside of the tank is a liquid of uniform concentration when it is not frozen, but when ice 14 is attached, the inside of the ice is almost composed of water molecules, The solute in the outside is concentrated as the ice grows and becomes a thick liquid.
若し溶質として電解質を用いると、この濃度の変化は電
気伝導率計によって計ることが出来る。If an electrolyte is used as the solute, this change in concentration can be measured by an electric conductivity meter.
そこで、予め結氷率と電気伝導率との関係を調べておけ
ば、電気伝導率を結氷率に換算することが出来る。Therefore, if the relationship between the freezing rate and the electric conductivity is investigated in advance, the electric conductivity can be converted into the freezing rate.
この様な原理を利用して、本発明はなされたものであ
る。The present invention has been made by utilizing such a principle.
溶質としての電解質は、特に種類を限定されない。The electrolyte as a solute is not particularly limited in type.
又、本測定方式は、氷蓄熱槽の幾何的形状，冷却管周り
の氷の形状等に全く影響されずに用いることが出来る方
式である。Further, this measurement method can be used without being affected by the geometrical shape of the ice heat storage tank, the shape of ice around the cooling pipe, and the like.
例えば、水位差式（電極式，差圧式）では氷蓄熱槽が、
縦方向に一様な断面積を有していないと、必ずしも、水
位変化と結氷率の関係が直線的とならず、換算が難し
い。For example, in the water level difference type (electrode type, differential pressure type), the ice heat storage tank
If it does not have a uniform cross-sectional area in the vertical direction, the relationship between the water level change and the freezing rate is not always linear, and conversion is difficult.
又、本来、局所結氷率センサーである接触式，電極式，
ダイヤフラム式等では、氷が冷却管の周りに同心円状か
つ一様に成長，融解しないと大きな誤差を生ずるが、本
発明の方式は、氷がどの様な形でどの様な分布で存在し
ても構わない特長を有するものである。In addition, the contact type, the electrode type, which is originally a local freezing rate sensor,
In the diaphragm type and the like, a large error occurs unless ice grows concentrically and uniformly around the cooling pipe and melts. However, in the method of the present invention, the ice exists in any shape and in any distribution. However, it has a feature that does not matter.
次に本発明の実施例についで述べる。Next, examples of the present invention will be described.
［実施例］ 第１図は、本発明の実施例の説明図である。[Embodiment] FIG. 1 is an explanatory view of an embodiment of the present invention.
図において、5:電気伝導率計,6:結氷率計であり、
（尚、符号１〜４は、前述中の符号と同一又は相当部分
を示すものである。）電気伝導率計５を氷蓄熱槽１中の
ある一ケ所に設置したものである。In the figure, 5: electric conductivity meter, 6: freezing rate meter,
(Note that reference numerals 1 to 4 indicate the same or corresponding portions as the above-mentioned reference numerals.) The electric conductivity meter 5 is installed in one place in the ice heat storage tank 1.
結氷率計６は計測された電気伝導率から結氷率を算出
し、表示又は信号出力を行うものである。The freezing rate meter 6 calculates the freezing rate from the measured electrical conductivity and displays or outputs a signal.
第２図は、本発明の他の実施例の説明図であり、液相部
分のより平均的な電気伝導率を計測し、槽全体としての
結氷率をより精度良く計ろうとするものである。FIG. 2 is an explanatory view of another embodiment of the present invention, in which a more average electric conductivity of the liquid phase portion is measured and the freezing rate of the entire tank is measured with higher accuracy.
図において、7:サンプリングポンプ,8:液サンプリング
管,9:液戻り管,10:ポットである。In the figure, 7: sampling pump, 8: liquid sampling pipe, 9: liquid return pipe, and 10: pot.
第２図の実施例においては、氷蓄熱槽１中の液は、複数
個の取出口を有する液サンプリング管８よりサンプリン
グポンプ７によって槽外に引抜かれ、ポット10に送ら
れ、この場所で電気伝導率計５によって電気伝導率が計
測される。In the embodiment shown in FIG. 2, the liquid in the ice heat storage tank 1 is drawn out of the tank by a sampling pump 7 from a liquid sampling pipe 8 having a plurality of outlets and is sent to a pot 10 where electricity is stored. The electric conductivity is measured by the conductivity meter 5.
ポット10を出たサンプル水は、液戻り管９によりて氷蓄
熱槽１に戻される。The sample water exiting the pot 10 is returned to the ice heat storage tank 1 by the liquid return pipe 9.
第２図の方式において、氷蓄熱槽１中の実際の結氷率α
（％）と液相の電気伝導率Ｋ（ｍΩ−１/cm）の計測結
果を第３図に示す。In the method of FIG. 2, the actual freezing rate α in the ice storage tank 1
(%) And the electric conductivity K (mΩ −1 / cm) of the liquid phase are shown in FIG.
尚、この例の場合では、電解質としてKOH（水酸化カリ
ウム）を0.2％入れてある。In this example, 0.2% of KOH (potassium hydroxide) was added as an electrolyte.
結氷率α（％）と液相の電気伝導率Ｋ（ｍΩ−１/cm）
との関係は、第３図に示す如く、結氷率α（％）が大き
くなるほど電気伝導率Ｋの変化幅が大きくなる様な曲線
となっている。Freezing rate α (%) and electric conductivity of liquid phase K (mΩ -1 / cm)
As shown in FIG. 3, the relationship between and is such a curve that the change width of the electric conductivity K increases as the freezing rate α (%) increases.
そこで、濃縮比ＲをＲ＝100/（100−α）で定義し、こ
れを横座標にとり、このＲにおけるＫをプロットする
と、第４図の様に電気伝導率Ｋと濃縮比Ｒとの関係は、
ほぼ直線に近い関係となっていることが分る。Therefore, the concentration ratio R is defined as R = 100 / (100−α), this is taken on the abscissa, and the K at this R is plotted. The relationship between the electrical conductivity K and the concentration ratio R is shown in FIG. Is
It can be seen that the relationship is almost linear.
つまり、第４図ではＫ＝αＲ＋ｂの様式で表される。That is, it is represented in the form of K = αR + b in FIG.
この式より、与えられた電解質の種類，初期濃度に対し
て予め定数a,bを求めておけば、電気伝導率Ｋを結氷率
αに換算することが出来る。From this equation, if the constants a and b are obtained in advance for the given type of electrolyte and initial concentration, the electrical conductivity K can be converted into the freezing rate α.
尚、この換算は第３図の結氷率α（％）と液相の電気伝
導率Ｋとの関係から直接行っても同様に可能である。Note that this conversion can be performed directly from the relationship between the freezing rate α (%) and the electric conductivity K of the liquid phase shown in FIG.
［発明の効果］ 本発明の結氷率の測定方法によれば、次の如き効果を奏
するものである。[Effects of the Invention] According to the method for measuring a freezing rate of the present invention, the following effects are exhibited.
（１）氷蓄熱槽全体としての結氷率を、液相の電気伝導
率を計測することにより連続的に計測することが出来、
氷蓄熱槽の運転管理、制御が容易になる。(1) The freezing rate of the entire ice heat storage tank can be continuously measured by measuring the electrical conductivity of the liquid phase,
Operation management and control of the ice heat storage tank becomes easy.
（２）結氷率の変化に対する液相電気伝導率の変化幅は
大きく、通常の簡易式の安価な電気伝導率計を用いても
十分な精度で計測出来る。(2) The change range of the liquid phase electric conductivity with respect to the change of the freezing rate is large, and the measurement can be performed with sufficient accuracy even by using an ordinary simple inexpensive electric conductivity meter.
第１図及び第２図は、本発明の実施例説明図、第３図
は、結氷率α（％）と液相の電気伝導率Ｋとの関係グラ
フ、第４図は、電気伝導率Ｋと濃縮比Ｒとの関係グラ
フ、第５図〜第９図は、従来の結氷率センサーの説明
図、第10図は、空調用の氷蓄熱槽の構造及び運転方法の
説明図、第11図及び第12図は、氷の成長に伴う液部の濃
度変化の説明図である。 図において、1:氷蓄熱槽,2:冷却管,3:循環ポンプ,4:熱
交換器,5:電気伝導率計,6:結氷率計,7:サンプリングポ
ンプ,8:液サンプリング管,9:液戻り管,10:ポット,11:検
出針,12:駆動部,13:電極,14:氷,15:マイクロスイッチセ
ンサー,16:差圧計。1 and 2 are explanatory views of an embodiment of the present invention, FIG. 3 is a graph showing a relation between freezing rate α (%) and electric conductivity K of liquid phase, and FIG. 4 is electric conductivity K. 5 to 9 are explanatory diagrams of a conventional freezing rate sensor, and FIG. 10 is an explanatory diagram of a structure and an operating method of an ice heat storage tank for air conditioning, and FIG. FIG. 12 and FIG. 12 are explanatory diagrams of changes in the concentration of the liquid portion with the growth of ice. In the figure, 1: ice storage tank, 2: cooling pipe, 3: circulation pump, 4: heat exchanger, 5: electric conductivity meter, 6: freezing rate meter, 7: sampling pump, 8: liquid sampling tube, 9 : Liquid return pipe, 10: Pot, 11: Detection needle, 12: Drive part, 13: Electrode, 14: Ice, 15: Micro switch sensor, 16: Differential pressure gauge.
Claims (1)
電解質を溶解させておき、凍結進行中に氷蓄熱槽内の液
相部の電気伝導度を測定して、予め求めておいた結氷率
と前記電気伝導度との関係を用いて、氷蓄熱槽内の結氷
率を求めることを特徴とする氷蓄熱槽内の結氷率の測定
方法。1. An electrolyte having a predetermined concentration is dissolved in water in an ice heat storage tank before freezing is started, and electric conductivity of a liquid phase portion in the ice heat storage tank is measured while freezing is in progress to be determined in advance. A method for measuring the rate of ice formation in an ice storage tank, wherein the rate of ice formation in the ice storage tank is determined by using the relationship between the set rate of ice formation and the electric conductivity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62027177A JPH0684943B2 (en) | 1987-02-10 | 1987-02-10 | Method for measuring the rate of freezing in the ice storage tank |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62027177A JPH0684943B2 (en) | 1987-02-10 | 1987-02-10 | Method for measuring the rate of freezing in the ice storage tank |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63195551A JPS63195551A (en) | 1988-08-12 |
| JPH0684943B2 true JPH0684943B2 (en) | 1994-10-26 |
Family
ID=12213790
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62027177A Expired - Lifetime JPH0684943B2 (en) | 1987-02-10 | 1987-02-10 | Method for measuring the rate of freezing in the ice storage tank |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0684943B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06105231B2 (en) * | 1988-05-26 | 1994-12-21 | 株式会社竹中工務店 | Signal processing method of ice amount sensor |
| JPH03163342A (en) * | 1989-11-22 | 1991-07-15 | Ohbayashi Corp | Method for detecting amount of ice in ice heat storage tank |
| CN103476841B (en) | 2011-03-29 | 2015-04-29 | 株式会社可乐丽 | Poly(vinyl acetal) resin film and multilayer structure using same |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52135797A (en) * | 1976-05-08 | 1977-11-14 | Mitsubishi Electric Corp | Apparatus for detecting phase change of liquid |
-
1987
- 1987-02-10 JP JP62027177A patent/JPH0684943B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63195551A (en) | 1988-08-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |