JP3949044B2 - Enthalpy of saturated water, latent heat of vaporization of saturated water, enthalpy of superheated steam, dryness measurement method and apparatus for wet steam - Google Patents

Description

係数ｋ₁は、例えば、１０００の４乗根に設定する。
【００２９】
飽和水エンタルピ導出手段８２について説明を加えると、飽和水エンタルピ導出手段８２は、飽和水のエンタルピｉ１（ｋＪ／ｋｇ）を、上記の数６にて求めた湿り蒸気指標値ｐを変数とする下記の数７にて示される飽和水エンタルピ導出用の２次式にて求める。
【００３０】
【数７】
ｉ１＝ｋ₂×ｐ²＋ｋ₃×ｐ＋ｋ₄
ｋ₂、ｋ₃、ｋ₄は定数であり、例えば、以下のように設定する。
ｋ₂＝−１．８８７１
ｋ₃＝１５６．０１
ｋ₄＝−５４．８４６
【００３１】
飽和水蒸発潜熱導出手段８３について説明を加えると、飽和水蒸発潜熱導出手段８３は、飽和水の蒸発潜熱ｒ（ｋＪ／ｋｇ）を、上記の数６にて求めた湿り蒸気指標値ｐを変数とする下記の数８にて示される飽和水蒸発潜熱導出用の２次式にて求める。
【００３２】
【数８】
ｒ＝ｋ₅×ｐ²＋ｋ₆×ｐ＋ｋ₇
ｋ₅、ｋ₆、ｋ₇は定数であり、例えば、以下のように設定する。
ｋ₅＝−３．６５９０
ｋ₆＝−６５．７４６
ｋ₇＝２５００．２９
【００３３】
過熱蒸気指標値導出手段８４について説明を加えると、過熱蒸気指標値導出手段８４は、過熱蒸気圧力センサ６にて検出される過熱蒸気のゲージ圧力をＰ₂（ＭＰａＧ）とすると、係数用指標値ａを、過熱蒸気の圧力Ｐ₂を変数とする下記の数９の係数用指標値導出用の一次式にて求め、並びに、定数項用指標値ｂを、過熱蒸気の圧力Ｐ₂を変数とする下記の数１０の定数項用指標値導出用の一次式にて求める。
【００３４】
【数９】
ａ＝ｋ₈×Ｐ₂＋ｋ₉
【００３５】
【数１０】
ｂ＝ｋ₁₀×Ｐ₂＋ｋ₁₁
ｋ₈、ｋ₉、ｋ₁₀、ｋ₁₁は定数であり、例えば、以下のように設定する。
ｋ₈＝０．１７０２
ｋ₉＝０．４７６２５
ｋ₁₀＝−４４．４６４
ｋ₁₁＝５９１．６２５
【００３６】
過熱蒸気エンタルピ導出手段８５について説明を加えると、過熱蒸気エンタルピ導出手段８５は、過熱蒸気のエンタルピｉ２（ｋＪ／ｋｇ）を、係数用指標値ａを過熱蒸気の温度Ｔ（°Ｃ）を変数とする項の係数とし且つ定数項用指標値ｂを定数項とする下記の数１１の過熱蒸気エンタルピ導出用の一次式により求める。
【００３７】
【数１１】
ｉ２＝４．１８６０５×（ａ×Ｔ₂＋ｂ）
【００３８】
そして、乾き度導出手段８６は、湿り蒸気の乾き度ｘを、上述のようにして求められた飽和水のエンタルピｉ１、飽和水の蒸発潜熱ｒ及び過熱蒸気のエンタルピｉ２に基づいて、上記の数５により求める。
【００３９】
操作部９は、飽和水のエンタルピｉ１、飽和水の蒸発潜熱ｒ、過熱蒸気のエンタルピｉ２及び湿り蒸気の乾き度ｘのうちから、測定するものを選択自在に指令することができるように構成してあり、処理部８は、操作部９から指令されたものを測定するように機能すると共に、その測定結果を表示部１０に表示させる。
【００４０】
つまり、飽和水のエンタルピｉ１の測定が指令されると、湿り蒸気指標値導出手段８１及び飽和水エンタルピ導出手段８２が作動して飽和水のエンタルピｉ１が測定され、その測定された飽和水のエンタルピｉ１が表示部１０に表示され、飽和水の蒸発潜熱ｒの測定が指令されると、湿り蒸気指標値導出手段８１及び飽和水蒸発潜熱導出手段８３が作動して、飽和水の蒸発潜熱ｒが測定され、その測定された飽和水の蒸発潜熱ｒが表示部１０に表示される。
又、過熱蒸気のエンタルピｉ２の測定が指令されると、過熱蒸気指標値導出手段８４及び過熱蒸気エンタルピ導出手段８５が作動して過熱蒸気のエンタルピｉ２が測定され、その測定された過熱蒸気のエンタルピｉ２が表示部１０に表示される。
又、湿り蒸気の乾き度ｘの測定が指令されると、湿り蒸気指標値導出手段８１、飽和水エンタルピ導出手段８２、飽和水蒸発潜熱導出手段８３、過熱蒸気指標値導出手段８４、過熱蒸気エンタルピ導出手段８５及び乾き度導出手段８６が作動して、湿り蒸気の乾き度ｘが測定され、その測定された乾き度ｘが表示部１０に表示される。
【００４１】
上記のように構成した湿り蒸気の乾き度測定装置によれば、飽和水のエンタルピｉ１、飽和水の蒸発潜熱ｒ、過熱蒸気のエンタルピｉ２及び湿り蒸気の乾き度ｘを連続して測定することが可能である。
【００４２】
〔別実施形態〕
次に別実施形態を説明する。
（イ） 上記の実施形態においては、湿り蒸気の乾き度測定装置の実施形態について説明したが、以下、図１に基づいて、飽和水のエンタルピ測定装置、飽和水の蒸発潜熱測定装置、及び、過熱蒸気のエンタルピ測定装置夫々の実施形態について説明する。
飽和水のエンタルピ測定装置は、上記の実施形態において説明した湿り蒸気の乾き度測定装置のうちの、測定用蒸気供給路１、湿り蒸気圧力センサ５、処理部８、操作部９及び表示部１０を備えて構成し、処理部８には、湿り蒸気指標値導出手段８１及び飽和水エンタルピ導出手段８２を備える。
【００４３】
飽和水の蒸発潜熱測定装置は、上記の実施形態において説明した湿り蒸気の乾き度測定装置のうちの、測定用蒸気供給路１、湿り蒸気圧力センサ５、処理部８、操作部９及び表示部１０を備えて構成し、処理部８には、湿り蒸気指標値導出手段８１及び飽和水蒸発潜熱導出手段８３を備える。
【００４４】
過熱蒸気のエンタルピ測定装置は、上記の実施形態において説明した湿り蒸気の乾き度測定装置のうちの、測定用蒸気供給路１、断熱膨張器２、蒸気排出路３、流量調整弁４、過熱蒸気圧力センサ６、過熱蒸気温度センサ７、処理部８、操作部９及び表示部１０を備えて構成し、処理部８には、過熱蒸気指標値導出手段８４及び過熱蒸気エンタルピ導出手段８５を備える。
【００４５】
（ロ） 上記の実施形態において、飽和水エンタルピ導出用のｎ次式及び飽和水蒸発潜熱導出用のｎ次式として、夫々、２次の多項式を設定したが、１次の多項式を設定したり、３次以上の多項式を設定しても良い。但し、１次の多項式では誤差が大きくなるので、２次以上の多項式に設定するのが好ましい。
【００４６】
（ハ） 飽和水のエンタルピｉ１を、上記の数６にて示される湿り蒸気指標値導出用の式及び数７にて示される飽和水エンタルピ導出用の２次式により、人為的に演算して求めても良い。
飽和水の蒸発潜熱ｒを、上記の数６にて示される湿り蒸気指標値導出用の式及び数８にて示される飽和水蒸発潜熱導出用の２次式により、人為的に演算して求めても良い。
過熱蒸気のエンタルピｉ２を、上記の数９にて示される係数用指標値導出用の一次式、数１０にて示される定数項用指標値導出用の一次式及び数１１にて示される過熱蒸気エンタルピ導出用の一次式により、人為的に演算して求めても良い。
湿り蒸気の乾き度ｘを、以下のように、人為的に演算することにより求めても良い。即ち、上述のように飽和水のエンタルピｉ１、飽和水の蒸発潜熱ｒ及び過熱蒸気のエンタルピｉ２を演算して求めると共に、それら飽和水のエンタルピｉ１、飽和水の蒸発潜熱ｒ及び過熱蒸気のエンタルピｉ２に基づいて、上記の数５により、湿り蒸気の乾き度ｘを求める。
【００４７】
（ニ） 定数ｋ₁，ｋ₂，ｋ₃，ｋ₄，ｋ₅，ｋ₆，ｋ₇，ｋ₈，ｋ₉，ｋ₁₀，ｋ₁₁の具体値は、上記の実施形態において例示した値に限定されるものではなく、導出目的の各値を精度良く求めることができるようにすべく、種々に設定することができる。例えば、湿り蒸気の乾き度を０〜１００％の間で複数の範囲に分けて、各範囲毎に、乾き度を精度良く測定することができるように、前記各定数を設定すると、湿り蒸気の乾き度の測定精度を一段と向上することが可能となる。
【図面の簡単な説明】
【図１】本発明の実施形態にかかる湿り蒸気の乾き度測定装置を示すブロック図
【符号の説明】
２ 断熱膨張器
５ 湿り蒸気圧力検出手段
６ 過熱蒸気圧力検出手段
７ 過熱蒸気温度検出手段
８１ 湿り蒸気指標値導出手段
８２ 飽和水エンタルピ導出手段
８３ 飽和水蒸発潜熱導出手段
８４ 過熱蒸気指標値導出手段
８５ 過熱蒸気エンタルピ導出手段
８６ 乾き度導出手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and an apparatus for measuring the enthalpy of saturated water, the latent heat of vaporization of saturated water, the enthalpy of superheated steam, and the dryness of wet steam.
[0002]
[Prior art]
The management of the steam used in each processing such as processing and sterilization of the workpiece is performed by measuring the mass ratio of dry saturated steam in the wet steam, that is, the dryness.
As a method of measuring the dryness of the wet steam, the wet steam to be measured is adiabatically expanded to be superheated steam, and the enthalpy and latent heat of evaporation of the saturated water before the adiabatic expansion and the superheated steam after the adiabatic expansion are measured. The enthalpy is measured as information for determining the dryness of the wet steam, and the dryness x of the wet steam is expressed by the above equation 1 by the enthalpy i1 of the saturated water, the latent heat of evaporation r, and the enthalpy i2 of the superheated steam. The method of seeking is known.
Conventionally, as a wet steam dryness measuring device that measures the dryness of wet steam using the above method, a wet steam pressure sensor that detects the pressure of the wet steam to be measured, superheated steam after adiabatic expansion A superheated steam temperature sensor that detects the temperature of the superheated steam and a superheated steam pressure sensor that detects the pressure of the superheated steam after adiabatic expansion are provided. The wet steam pressure detected by the wet steam pressure sensor and the superheated steam temperature sensor detect There is one that calculates the dryness of the wet steam based on the temperature of the superheated steam to be detected and the pressure of the superheated steam detected by the superheated steam pressure sensor (see, for example, Patent Document 1).
The conventional wet steam dryness measuring apparatus may be referred to as the first prior art in the following description.
In the first prior art, there is no description of a method for calculating the dryness of the wet steam based on the pressure of the wet steam, the temperature of the superheated steam, and the pressure of the superheated steam, but the dryness is as follows. It is thought that it is what calculates.
That is, the saturated steam table indicating the relationship between the pressure, enthalpy and latent heat of vaporization of the wet steam, and the superheated steam table indicating the relationship between the temperature, pressure and enthalpy of the superheated steam are stored in the storage means. The saturated water enthalpy and latent heat of vaporization are obtained based on the measured pressure and the saturated steam table stored in the storage means, and the measured temperature and measured pressure of the superheated steam and the superheated steam stored in the storage means Based on the table, the enthalpy of the superheated steam is obtained, and the dryness of the wet steam is calculated by the above equation 1 based on the enthalpy and latent heat of evaporation of the saturated water and the enthalpy of the superheated steam thus obtained. it is conceivable that.
[0003]
Conventionally, as a wet steam dryness measuring device for measuring the wet steam dryness, there is a second prior art described below in addition to the first prior art described above (see, for example, Patent Document 2). ).
This second prior art supplies wet vapor to be measured to a measurement container that stores a predetermined amount of liquid, detects the amount of supplied wet vapor and the temperature change of the liquid in the measurement container, and so on. Based on the detected amount of wet steam and liquid temperature, the enthalpy of the supplied wet steam is calculated as information for determining the dryness of the wet steam based on calorie conversion, and the dryness of the wet steam is calculated from the enthalpy. It was composed.
In other words, the relationship between the dryness of wet steam and enthalpy is that the dryness of dry saturated steam is 100%, the dryness of saturated water is 0%, and the enthalpy of dry saturated steam and saturated water is enthalpy at each pressure. Since it is uniquely determined by proportionally distributing between the values, the relationship between the dryness and enthalpy for each pressure is stored in the storage means, and the dryness is obtained from the calculated enthalpy of the wet steam to be measured. It is comprised as follows.
[0004]
[Patent Document 1]
JP 2002-174578 A
[Patent Document 2]
JP 2002-243676 A
[0005]
[Problems to be solved by the invention]
However, in the first prior art, each of the enthalpy of saturated water and the latent heat of vaporization of saturated water is measured based on the saturated steam table, so a large amount of data such as the saturated steam table needs to be stored in the storage means. Therefore, a storage device having a large storage capacity and a high price is required, leading to an increase in measurement cost, and when the detected pressure of the wet steam to be measured is not included in the saturated steam table, that is, the detected pressure is When the value is between the adjacent pressures in the saturated steam table, there is a problem that the measurement accuracy of the enthalpy of saturated water and the latent heat of evaporation of saturated water becomes low.
In other words, if the detected pressure is a value between adjacent pressures in the saturated steam table, it can be considered that the enthalpy and latent heat of vaporization corresponding to the adjacent pressures are simply proportionally determined. Since the relationship between pressure and enthalpy and the relationship between pressure and latent heat of vaporization are not just a linear function, as described above, when enthalpy and latent heat of vaporization are obtained by proportional distribution, their accuracy is Lower.
Incidentally, in order to solve the problem that the measurement accuracy of the enthalpy of saturated water and the latent heat of evaporation of saturated water is reduced due to the fact that the detected pressure of wet steam to be measured is not included in the saturated steam table, saturated steam Although it is conceivable to acquire the data in the table at as narrow a pressure interval as possible, it is necessary to spend time and effort to acquire the data, and as a storage means for storing the data, the price with a large storage capacity is even higher A problem arises that the cost of measuring saturated water enthalpy and saturated latent heat of vaporization is further increased.
[0006]
In the first prior art, since the enthalpy of superheated steam is measured based on the superheated steam table, it is necessary to store a large amount of data such as the superheated steam table in the storage means. A large and expensive product is required, leading to an increase in measurement cost, and when the detected temperature or detected pressure of the superheated steam to be measured is not included in the superheated steam table, that is, the detected temperature is adjacent to the superheated steam table. When the value is between the two temperatures, or when the detected pressure is a value between adjacent pressures in the superheated steam table, there is a problem that the measurement accuracy of the enthalpy of the superheated steam is lowered.
In other words, the relationship between pressure and enthalpy, and the relationship between temperature and enthalpy is not a relationship represented by a simple linear function, so the detected temperature is a value between adjacent temperatures in the superheated steam table. In this case, or when the detected pressure is a value between adjacent pressures in the superheated steam table, if the adjacent enthalpies are obtained simply by proportional distribution, the accuracy becomes low.
By the way, in order to solve the problem that the measurement accuracy of superheated steam enthalpy is reduced due to the detection temperature and pressure of the superheated steam to be measured not included in the superheated steam table, data in the superheated steam table is used. However, it is necessary to spend time and labor to acquire the data, and as a storage means for storing the data, there is a device with a higher storage capacity and a higher price. This becomes a problem, and the measurement cost of the enthalpy of the superheated steam is further increased.
[0007]
In the first prior art, as described above, the measurement accuracy of the enthalpy of saturated water, the latent heat of vaporization, and the enthalpy of superheated steam as information for obtaining the dryness of the wet steam is poor. Further, the accuracy of the dryness of the wet steam obtained based on the enthalpy of the latent heat of vaporization and superheated steam is lowered.
[0008]
In the second prior art, the enthalpy of the wet steam is obtained based on the amount of the wet steam and the temperature of the wet steam. However, since the measurement method of the wet steam is complicated and difficult to measure accurately, There was a problem that the measurement accuracy of the enthalpy of steam was lowered.
In the second prior art, since the measurement accuracy of the enthalpy of the wet steam is low as information for determining the dryness of the wet steam, the accuracy of the dryness of the wet steam obtained based on the enthalpy of the wet steam is low. Become.
In addition, since the configuration for measuring the amount of wet steam becomes complicated, there has been a problem that the price of the apparatus rises and the measurement cost of the enthalpy of wet steam increases.
In short, in the past, information for measuring the dryness of wet steam, such as the enthalpy of saturated water, the latent heat of vaporization of saturated water, the enthalpy of superheated steam, and the enthalpy of wet steam, improve the measurement accuracy. In addition, there is a problem that it is difficult to reduce the measurement cost.
[0009]
The present invention has been made in view of such circumstances, and its purpose is to improve the measurement accuracy of information for measuring the dryness of wet steam and to reduce the measurement cost, and the enthalpy and saturation of saturated water. An object is to provide a method and an apparatus for measuring the latent heat of vaporization of water, the enthalpy of superheated steam, and the dryness of wet steam.
[0010]
[Means for Solving the Problems]
[Invention of Claim 1]
The method for measuring enthalpy of saturated water according to claim 1 obtains a wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam to be measured by a coefficient, and uses the wet steam index value as a variable. The feature configuration is that the enthalpy i1 of saturated water is obtained by an nth-order equation for derivation.
That is, the absolute pressure of the wet steam to be measured is measured, the fourth root of the absolute pressure is obtained, the wet root index value is obtained by multiplying the fourth root of the obtained absolute pressure by a coefficient, and the obtained wet pressure is obtained. The saturated water enthalpy i1 is obtained by substituting the steam index value into the nth order equation for deriving the saturated water enthalpy using the wet steam index value as a variable.
In other words, the inventor of the present invention has intensively studied to improve the measurement accuracy and reduce the measurement cost in measuring the enthalpy of saturated water. The enthalpy of saturated water is the fourth root of the absolute pressure of wet steam. It was found that the approximation can be made with high accuracy by an nth order equation using a wet steam index value obtained by multiplying a predetermined coefficient as a variable.
The wet steam index value obtained by multiplying the fourth root of the absolute pressure of the wet steam by a predetermined coefficient is used as a variable. In other words, the enthalpy of saturated water can be accurately approximated using the absolute pressure of the wet steam as a variable. Since the saturated water enthalpy is obtained by substituting the measured value of the absolute pressure of the wet steam to be measured into the nth order equation for deriving the saturated water enthalpy, the enthalpy of the saturated water can be measured with high accuracy.
Further, since no saturated steam table is used, it is not necessary to acquire precise saturated steam table data in order to improve the measurement accuracy, as required in the first prior art. Since it is possible to measure the enthalpy of saturated water with a simple configuration such as measuring the pressure of the steam, the measurement cost can be reduced.
Accordingly, it is possible to provide a saturated water enthalpy measurement method capable of improving the measurement accuracy of saturated water enthalpy as information for measuring the dryness of wet steam and reducing the measurement cost.
[0011]
[Invention of Claim 2]
The saturated water enthalpy measuring device according to claim 2, wherein the wet steam pressure detecting means for detecting the pressure of the wet steam to be measured;
Wet steam index value deriving means for obtaining the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam by a coefficient based on the detection information of the wet steam pressure detecting means;
Saturated water enthalpy deriving means for obtaining saturated water enthalpy i1 by an nth-order equation for deriving saturated water enthalpy using the wet steam index value as a variable is provided.
That is, the wet steam pressure detecting means detects the pressure of the wet steam to be measured, and the wet steam index value deriving means is based on the detection information of the wet steam pressure detecting means to the fourth root of the absolute pressure of the wet steam. The wet steam index value is obtained by multiplying the coefficient, and the saturated water enthalpy derivation means is used to derive the saturated water enthalpy using the wet steam index value as a variable. By substituting into the nth order equation, the enthalpy i1 of saturated water is obtained.
In other words, as described above with respect to the invention of claim 1, the enthalpy of saturated water is an n-th order using a wet steam index value obtained by multiplying the fourth root of the absolute pressure of wet steam by a predetermined coefficient as a variable. In the equation, it is found that it can be accurately approximated, and the wet steam index value obtained by multiplying the fourth root of the absolute pressure of the wet steam by a predetermined coefficient as a variable, in other words, the absolute value of the wet steam Substituting the measured value of the absolute pressure of the wet steam to be measured into the nth order equation for deriving the saturated water enthalpy, which is set to be able to approximate the saturated water enthalpy accurately with the pressure as a variable, Therefore, it is possible to accurately measure the enthalpy of saturated water.
Also, since the enthalpy of saturated water is obtained by a simple formula without using a saturated steam table with a large amount of information, it becomes possible to use an inexpensive one with a small storage capacity as a storage means, Since it is possible to measure the enthalpy of saturated water with a simple configuration such as measuring pressure, it is possible to reduce the cost of the equipment and, in turn, to reduce the cost of measuring enthalpy of saturated water. Is possible.
Therefore, it has become possible to provide a saturated water enthalpy measurement device capable of improving the measurement accuracy of saturated water enthalpy as information for measuring the dryness of wet steam and reducing the measurement cost.
[0012]
[Invention of Claim 3]
The method for measuring latent heat of evaporation of saturated water according to claim 3 obtains a wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam to be measured by a coefficient, and uses the wet steam index value as a variable. The characteristic configuration is that the latent heat of vaporization r of saturated water is obtained by an nth order equation for deriving latent heat of vaporization.
That is, the absolute pressure of the wet steam to be measured is measured, the fourth root of the absolute pressure is obtained, the wet root index value is obtained by multiplying the fourth root of the obtained absolute pressure by a coefficient, and the obtained wet pressure is obtained. By substituting the steam index value into an nth-order equation for deriving saturated water evaporation latent heat with the wet steam index value as a variable, the evaporation latent heat r of saturated water is obtained.
That is, the inventor of the present invention has intensively studied to improve the measurement accuracy and reduce the measurement cost when measuring the latent heat of evaporation of saturated water. The latent heat of evaporation of saturated water is 4 of the absolute pressure of wet steam. It has been found that the approximation can be performed with high accuracy by an nth order equation using a wet steam index value obtained by multiplying the root of the product by a predetermined coefficient as a variable.
Then, the wet steam index value obtained by multiplying the fourth root of the absolute pressure of the wet steam by a predetermined coefficient is used as a variable, in other words, the latent heat of evaporation of saturated water is accurately approximated using the absolute pressure of the wet steam as a variable. Substituting the measured value of the absolute pressure of the wet steam to be measured into the n-th order equation for deriving the saturated water evaporation latent heat, and obtaining the evaporation latent heat of saturated water, the evaporation latent heat of saturated water can be accurately measured. It becomes possible.
Further, since no saturated steam table is used, it is not necessary to acquire precise saturated steam table data in order to improve the measurement accuracy, as required in the first prior art. Since the latent heat of vaporization of saturated water can be measured with a simple configuration such as measuring the pressure of the steam, the measurement cost can be reduced.
Therefore, it is possible to provide a method for measuring the latent heat of evaporation of saturated water that can improve the measurement accuracy of the latent heat of evaporation of saturated water as information for measuring the dryness of wet steam and can reduce the measurement cost. It was.
[0013]
[Invention of Claim 4]
The apparatus for measuring latent heat of evaporation of saturated water according to claim 4 comprises wet steam pressure detecting means for detecting the pressure of wet steam to be measured,
Wet steam index value deriving means for obtaining the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam by a coefficient based on the detection information of the wet steam pressure detecting means;
Saturated water evaporation latent heat deriving means for obtaining saturated water evaporation latent heat r by an n-order equation for deriving saturated water evaporation latent heat using the wet steam index value as a variable is provided.
That is, the wet steam pressure detecting means detects the pressure of the wet steam to be measured, and the wet steam index value deriving means is based on the detection information of the wet steam pressure detecting means to the fourth root of the absolute pressure of the wet steam. Multiplying the coefficient to obtain the wet steam index value, the saturated water evaporation latent heat deriving means derives the saturated water evaporation latent heat using the wet steam index value obtained by the wet steam index value deriving means as a variable. By substituting into the n-th order equation, the evaporation latent heat r of saturated water is obtained.
That is, as described above for the invention of claim 3, the latent heat of vaporization of saturated water is a variable n that is a wet steam index value obtained by multiplying the fourth root of the absolute pressure of wet steam by a predetermined coefficient. In the following equation, it is found that it can be approximated with high accuracy, and the wet steam index value obtained by multiplying the fourth root of the absolute pressure of the wet steam by a predetermined coefficient as a variable, in other words, Substituting the measured value of the absolute pressure of the wet steam to be measured into the nth order equation for deriving the saturated water evaporation latent heat, which is set so that the latent heat of vaporization of the saturated water can be accurately approximated using the absolute pressure as a variable, Therefore, it is possible to accurately measure the latent heat of evaporation of saturated water.
In addition, since the latent heat of evaporation of saturated water is obtained by a simple mathematical formula without using a saturated steam table with a large amount of information, it is possible to use an inexpensive one with a small storage capacity as a storage means, or simply wet steam. It is possible to measure the latent heat of vaporization of saturated water with a simple configuration, such as measuring the pressure of the water, thereby reducing the cost of the equipment and, in turn, lowering the cost of measuring the latent heat of vaporization of saturated water. Can be achieved.
Accordingly, it is possible to provide an apparatus for measuring the latent heat of evaporation of saturated water capable of improving the measurement accuracy of the latent heat of evaporation of saturated water as information for measuring the dryness of wet steam and reducing the measurement cost. It was.
[0014]
[Invention of Claim 5]
The method for measuring the enthalpy of superheated steam according to claim 5 calculates the index value for the coefficient by a linear expression for deriving the index value for the coefficient with the pressure of the superheated steam to be measured as a variable, and the pressure of the superheated steam to be measured The index value for the constant term is obtained by a linear expression for deriving the index value for the constant term with the variable as the variable, the index value for the coefficient is set as the coefficient of the term with the temperature of the superheated steam as a variable, and the index value for the constant term is The characteristic configuration is that the enthalpy i2 of the superheated steam is obtained by a linear expression for deriving the superheated steam enthalpy as a constant term.
That is, the pressure and temperature of the superheated steam to be measured are measured, and the measured pressure is substituted into the primary expression for deriving the index value for the coefficient with the pressure of the superheated steam to be measured as a variable, and the index value for the coefficient is And substituting the measured pressure into a primary expression for deriving an index value for a constant term using the pressure of the superheated steam to be measured as a variable to obtain an index value for the constant term, and subsequently measuring the measured temperature, By substituting the index value for coefficient into a linear equation for deriving superheated steam enthalpy using the coefficient of the term having the temperature of the superheated steam as a variable and deriving the index value for the constant term as a constant term, the enthalpy i2 of the superheated steam is obtained.
In other words, the inventor of the present invention has earnestly studied to improve the measurement accuracy and reduce the measurement cost when measuring the enthalpy of superheated steam. The coefficient value obtained by the linear equation, that is, the coefficient for deriving the index value for the coefficient with the pressure of the superheated steam to be measured as a variable, as the coefficient of the first term with the temperature of the superheated steam as a variable, In addition, it can be accurately approximated by a linear expression using a constant term index value obtained by a linear expression for deriving a constant term index value using the pressure of the superheated steam to be measured as a variable. I found it.
And the three primary equations for deriving index values for coefficients, deriving index values for constant terms, and deriving superheated steam enthalpies, which are set so that the enthalpy of superheated steam can be accurately approximated using the pressure and temperature of superheated steam as variables, Since the enthalpy of the superheated steam is obtained by substituting the measured values of the pressure and temperature of the superheated steam to be measured, the enthalpy of the superheated steam can be accurately measured.
In addition, since no superheated steam table is used, it is not necessary to acquire accurate superheated steam table data in order to improve the measurement accuracy, as required in the first prior art, or simply overheating. Since it is possible to measure the enthalpy of superheated steam with a simple configuration such as measuring the pressure and temperature of the steam, the measurement cost can be reduced.
Accordingly, it is possible to provide a superheated steam enthalpy measurement method capable of improving the measurement accuracy of superheated steam enthalpy as information for measuring the dryness of wet steam and reducing the measurement cost.
[0015]
[Invention of Claim 6]
The superheated steam enthalpy measuring device according to claim 6 is provided with superheated steam pressure detecting means for detecting the pressure of the superheated steam to be measured, and superheated steam temperature detecting means for detecting the temperature,
Based on the detection information of the superheated steam pressure detecting means, a coefficient index value is obtained by a linear expression for deriving a coefficient index value using the superheated steam pressure as a variable, and a constant using the superheated steam pressure as a variable Superheated steam index value deriving means for obtaining an index value for a constant term with a linear expression for deriving an index value for a term;
Based on the detection information of the superheated steam temperature detecting means, the coefficient index value is a coefficient of a term having the temperature of the superheated steam as a variable, and the primary for deriving superheated steam enthalpy having the constant term index value as a constant term According to the formula, a superheated steam enthalpy deriving means for obtaining the enthalpy i2 of the superheated steam is provided.
That is, the superheated steam pressure detecting means detects the pressure of the superheated steam to be measured, the superheated steam temperature detecting means measures the temperature of the superheated steam to be measured, and the superheated steam index value deriving means determines the superheated steam pressure detecting means. Based on the detection information, the index value for the coefficient is obtained by a linear expression for deriving the index value for the coefficient using the pressure of the superheated steam as a variable, and for deriving the index value for the constant term using the pressure of the superheated steam as a variable The index value for the constant term is obtained by a linear expression, and the coefficient of the term with the temperature of the superheated steam as the variable is used as the coefficient index value based on the detection information of the superheated steam temperature detecting means by the superheated steam enthalpy deriving means. And the enthalpy i2 of the superheated steam is obtained by a linear expression for deriving the superheated steam enthalpy using the constant term index value as a constant term.
That is, as described above for the invention according to claim 5, the enthalpy of the superheated steam to be measured is a linear expression for deriving the superheated steam enthalpy, that is, a coefficient index having the pressure of the superheated steam to be measured as a variable. The index value for the coefficient obtained by the linear equation for deriving the value is the coefficient of the first-order term using the temperature of the superheated steam as a variable, and the index value for the constant term is derived using the pressure of the superheated steam to be measured as a variable It is found that it can be approximated with high accuracy by a linear expression that uses the constant term index value obtained from the linear expression for the constant term, and the enthalpy of the superheated steam is accurately determined using the pressure and temperature of the superheated steam as variables. Substituting the measured values of the pressure and temperature of the superheated steam to be measured into the three primary equations for deriving the index value for the coefficient, deriving the index value for the constant term, and deriving the superheated steam enthalpy that are set to be well approximated Superheated steam Since obtaining the enthalpy, it becomes possible to accurately measure the enthalpy of the superheated steam.
Moreover, since the enthalpy of superheated steam is obtained by a simple formula without using a superheated steam table with a large amount of information, it is possible to use an inexpensive one with a small storage capacity as a storage means, or simply Since it is possible to measure the enthalpy of superheated steam with a simple configuration such as measuring pressure and temperature, the cost of the equipment can be reduced, and in turn, the measurement cost of enthalpy of superheated steam can be reduced. It becomes possible to plan.
Therefore, it has become possible to provide a superheated steam enthalpy measurement device capable of improving the measurement accuracy of superheated steam enthalpy as information for measuring the dryness of wet steam and reducing the measurement cost.
[0016]
[Invention of Claim 7]
The wet steam dryness measuring method according to claim 7, wherein the wet steam index value is obtained by multiplying the fourth root of the absolute pressure of the wet steam to be measured by a coefficient, and the wet steam index value is used as a variable. The saturated water enthalpy i1 is obtained from the nth order equation for deriving enthalpy, the latent heat evaporating r of the saturated water is obtained from the nth order equation for deriving the latent heat of saturated water having the wet steam index value as a variable,
Obtain a coefficient index value with a primary expression for deriving a coefficient index value using the pressure of the superheated steam generated by adiabatic expansion of the measurement target wet steam as a variable, and a constant term with the pressure of the superheated steam as a variable The index value for the constant term is obtained by a linear expression for deriving the index value for the index, the index value for the coefficient is used as a coefficient of a term whose temperature is the temperature of the superheated steam, and the index value for the constant term is used as the constant term Obtain the enthalpy i2 of the superheated steam using the primary equation for enthalpy derivation,
Based on the enthalpy i1 of the saturated water, the latent heat of vaporization r of the saturated water and the enthalpy i2 of the superheated steam, the dryness x of the wet steam,
[0017]
[Equation 3]
x = (i2-i1) / r
[0018]
The point obtained in step is defined as a feature configuration.
That is, the absolute pressure of the wet steam to be measured is measured, the fourth root of the absolute pressure is obtained, the wet root index value is obtained by multiplying the fourth root of the obtained absolute pressure by a coefficient, and the obtained wet pressure is obtained. The saturated water enthalpy i1 is obtained by substituting the steam index value into the nth order equation for deriving the saturated water enthalpy using the wet steam index value as a variable.
Further, by substituting the wet steam index value into an nth-order equation for deriving saturated water evaporation latent heat with the wet steam index value as a variable, the latent heat of evaporation r of saturated water is obtained.
Furthermore, the pressure and temperature of the superheated steam generated by adiabatic expansion of the wet steam to be measured are measured, and the measured pressure is substituted into the primary expression for deriving the index value for the coefficient using the pressure of the superheated steam as a variable. The index value for the coefficient is obtained, and the measured pressure is substituted into the primary expression for deriving the index value for the constant term using the pressure of the superheated steam as a variable to obtain the index value for the constant term, followed by the measurement. Substituting temperature into the primary equation for deriving superheated steam enthalpy with the index value for coefficient as the coefficient of the term with the temperature of superheated steam as a variable and the index value for constant term as the constant term, the enthalpy of superheated steam Find i2.
Then, the enthalpy i1 of saturated water, the latent heat of evaporation r1 of saturated water and the enthalpy i2 of superheated steam measured as described above are substituted into the above Equation 3 to obtain the dryness x of wet steam.
In other words, as described above with respect to the invention of claim 1, the saturated water enthalpy i1 can be measured while improving the measurement accuracy and reducing the measurement cost by the nth order equation for deriving the saturated water enthalpy. In addition, as described in the third aspect of the present invention, the measurement accuracy of the evaporation latent heat r of saturated water can be improved and the measurement cost can be reduced by the nth order equation for deriving the latent heat of evaporation of saturated water. In addition, as described above with reference to the description of claim 5, three linear expressions for deriving index values for coefficients, deriving index values for constant terms, and deriving superheated steam enthalpy This makes it possible to measure the enthalpy of superheated steam while improving the measurement accuracy and reducing the measurement cost, and further improving the measurement accuracy and measuring cost of wet steam. It is possible to measure while achieving cost reduction.
Therefore, to improve the accuracy of measurement of enthalpy of saturated water as information for measuring the dryness of wet steam, the latent heat of evaporation of saturated water and the enthalpy of superheated steam, and to reduce the measurement cost, the dryness of wet steam It is now possible to provide a method for measuring the dryness of wet steam that can improve the measurement accuracy and reduce the measurement cost.
[0019]
[Invention of Claim 8]
The wet steam dryness measuring apparatus according to claim 8, wherein the wet steam pressure detecting means for detecting the pressure of the wet steam to be measured;
An adiabatic expander that adiabatically expands the wet steam to be measured into superheated steam;
Superheated steam pressure detecting means for detecting the pressure of the superheated steam generated by the adiabatic expander;
And a superheated steam temperature detecting means for detecting the temperature of the superheated steam,
Wet steam index value deriving means for obtaining the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam by a coefficient based on the detection information of the wet steam pressure detecting means;
Saturated water enthalpy derivation means for obtaining an enthalpy i1 of saturated water by an nth order equation for deriving saturated water enthalpy using the wet steam index value as a variable;
Saturated water evaporation latent heat deriving means for obtaining saturated water evaporation latent heat r by an nth-order equation for deriving saturated water evaporation latent heat with the wet steam index value as a variable;
Based on the detection information of the superheated steam pressure detecting means, a coefficient index value is obtained by a linear expression for deriving a coefficient index value using the superheated steam pressure as a variable, and a constant using the superheated steam pressure as a variable Superheated steam index value deriving means for obtaining an index value for a constant term with a linear expression for deriving an index value for a term;
Based on the detection information of the superheated steam temperature detecting means, the coefficient index value is a coefficient of a term having the temperature of the superheated steam as a variable, and the primary for deriving superheated steam enthalpy having the constant term index value as a constant term The superheated steam enthalpy deriving means for obtaining the superheated steam enthalpy i2 according to the equation is provided,
Based on the enthalpy i1 of the saturated water, the latent heat of vaporization r of the saturated water and the enthalpy i2 of the superheated steam,
[0020]
[Expression 4]
x = (i2-i1) / r
[0021]
The characteristic feature is that dryness deriving means for obtaining the dryness x of the wet steam is provided.
That is, the wet steam pressure detecting means detects the pressure of the wet steam to be measured, the superheated steam pressure detecting means detects the pressure of the superheated steam generated by the adiabatic expander, and the superheated steam temperature detecting means The temperature of the superheated steam generated by the adiabatic expander is detected.
The wet steam index value deriving means obtains the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam by a coefficient based on the detection information of the wet steam pressure detecting means, and the saturated water enthalpy deriving means By substituting the wet steam index value obtained by the steam index value deriving means into an nth order equation for deriving saturated water enthalpy using the wet steam index value as a variable, the enthalpy i1 of saturated water is obtained, and saturated water By substituting the wet steam index value into the nth-order equation for deriving saturated water evaporation latent heat with the wet steam index value as a variable, the latent heat of evaporation r of saturated water is obtained by the latent heat of vapor deriving means.
Based on the detection information of the superheated steam pressure detecting means, the superheated steam index value deriving means obtains a coefficient index value by a primary expression for deriving a coefficient index value using the superheated steam pressure as a variable, and An index value for the constant term is obtained by a linear expression for deriving an index value for the constant term with the steam pressure as a variable, and the coefficient for the coefficient is calculated by the superheated steam enthalpy deriving means based on the detection information of the superheated steam temperature detecting means. The enthalpy i2 of the superheated steam is obtained by a linear equation for deriving the superheated steam enthalpy using the index value as a coefficient of the term having the temperature of the superheated steam as a variable and the index value for the constant term as the constant term.
Then, by substituting the enthalpy i1 of saturated water, the latent heat of evaporation r1 of saturated water and the enthalpy i2 of superheated steam measured as described above by the dryness deriving means, the dryness x of the wet steam x Is required.
In other words, as described above for the invention of claim 2, the saturated water enthalpy i1 is measured by the wet steam index value deriving means and the saturated water enthalpy deriving means while improving the measurement accuracy and reducing the measurement cost. In addition, as described in the fourth aspect of the present invention, the measurement accuracy of the evaporation latent heat r of saturated water is improved by the wet steam index value deriving means and the saturated water evaporation latent heat deriving means. In addition, as described above, the superheated steam index value deriving means and the superheated steam enthalpy deriving means provide the enthalpy of the superheated steam. Can be measured while improving the measurement accuracy and reducing the measurement cost. As a result, the dryness of wet steam can be improved. It is possible to measure while achieving cost reduction of the fine measurement costs.
Therefore, to improve the accuracy of measurement of enthalpy of saturated water as information for measuring the dryness of wet steam, the latent heat of evaporation of saturated water and the enthalpy of superheated steam, and to reduce the measurement cost, the dryness of wet steam It has become possible to provide a wet steam dryness measuring device capable of improving the measurement accuracy and reducing the measurement cost.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1, the wet steam dryness measuring apparatus adiabatically expands the measurement steam supply path 1 that guides the wet steam to be measured and the wet steam supplied in the measurement steam supply path 1. Adiabatic expander 2 for making superheated steam, a steam discharge path 3 for discharging steam from the adiabatic expander 2, and a flow rate adjustment for adjusting the amount of wet steam supplied to the adiabatic expander 2 through the steam supply path 1 for measurement A wet steam pressure sensor 5 (corresponding to a wet steam pressure detecting means) that detects the pressure of wet steam at a location upstream of the flow rate adjusting valve 4 in the measurement steam supply path 1, and an adiabatic expander A superheated steam pressure sensor 6 (corresponding to a superheated steam pressure detection means) for detecting the pressure of superheated steam in the heat pump 2 and a superheated steam temperature sensor 7 (superheated steam temperature detection for detecting the temperature of the superheated steam in the adiabatic expander 2). Equivalent to the means) and those wet A processing unit 8 that calculates the dryness of the wet steam based on detection information of each of the steam pressure sensor 5, the superheated steam pressure sensor 6, and the superheated steam temperature sensor 7, and an operation unit 9 that instructs the processing unit 8 to process information. And a display unit 10 for displaying the calculation result of the processing unit 8.
[0023]
Since the adiabatic expander 2 is well known, detailed description and illustration are omitted, but wet steam supplied through the measurement steam supply path 1 is blown into the adiabatic expander 2 by giving a throttle and adiabatic expansion ( It is configured to be superheated steam by changing the enthalpy.
[0024]
The processing unit 8 is configured by using a microcomputer, and the processing unit 8 is based on the detection information of the wet steam pressure sensor 5 and multiplies the fourth root of the absolute pressure of the wet steam by a coefficient to obtain wet steam. Wet steam index value deriving means 81 for obtaining the index value p, and saturated water for obtaining the enthalpy i1 of the saturated water by an nth-order equation (n is a positive integer) for deriving saturated water enthalpy using the wet steam index value p as a variable. Enthalpy deriving means 82; saturated water evaporating latent heat deriving means 83 for obtaining saturated water evaporating latent heat r by an nth order equation (n is a positive integer) for deriving saturated water evaporating latent heat with wet steam index value p as a variable; Based on the detection information of the superheated steam pressure sensor 6, a coefficient index value a is obtained by a linear expression for deriving a coefficient index value using the superheated steam pressure as a variable, and a constant using the superheated steam pressure as a variable In the primary expression for deriving index values for terms Based on the detection information of the superheated steam index value deriving means 84 and the superheated steam temperature sensor 7 for obtaining the index value b for several terms, the index value for coefficient a is a coefficient of a term whose temperature is the temperature of the superheated steam, and the constant The superheated steam enthalpy deriving means 85 for obtaining the enthalpy i2 of the superheated steam by a linear expression for deriving the superheated steam enthalpy with the term index value b as a constant term, the enthalpy i1 of the saturated water, and the latent heat of vaporization r of the saturated water And a dryness deriving means 86 for obtaining the dryness x of the wet steam by the following equation 5 based on the enthalpy i2 of the superheated steam.
[0025]
[Equation 5]
x = (i2-i1) / r
[0026]
Specifically, each of wet steam index value deriving means 81, saturated water enthalpy deriving means 82, saturated water evaporation latent heat deriving means 83, superheated steam index value deriving means 84, superheated steam enthalpy deriving means 85, and dryness deriving means 86. Each means is constituted by a program for causing the processing unit 8 to function as each means, and these programs are stored in a storage unit (not shown) of the processing unit 8.
[0027]
The wet steam index value deriving unit 81 will be described. The wet steam index value deriving unit 81 calculates the gauge pressure of the wet steam to be measured detected by the wet steam pressure sensor 5 as P.₁Assuming (MPaG), the wet steam index value p is obtained by the following equation (6).
[0028]
[Formula 6]

Coefficient k₁Is set to the fourth power of 1000, for example.
[0029]
The saturated water enthalpy deriving unit 82 will be described. The saturated water enthalpy deriving unit 82 uses the wet steam index value p obtained by the above Equation 6 as a variable for the saturated water enthalpy i1 (kJ / kg). This is obtained by a quadratic equation for deriving saturated water enthalpy expressed by Equation (7).
[0030]
[Expression 7]
i1 = k₂× p²+ K_Three× p + k_Four
k₂, K_Three, K_FourIs a constant, and is set as follows, for example.
k₂= -1.8871
k_Three= 156.01
k_Four= −54.846
[0031]
When the saturated water evaporation latent heat deriving unit 83 is described further, the saturated water evaporation latent heat deriving unit 83 uses the wet steam index value p obtained by the above equation 6 as the variable for the latent heat of evaporation of saturated water r (kJ / kg). It calculates | requires by the secondary type | formula for derivation | leading-out saturated water evaporation latent heat shown by the following several 8.
[0032]
[Equation 8]
r = k_Five× p²+ K₆× p + k₇
k_Five, K₆, K₇Is a constant, and is set as follows, for example.
k_Five= -3.6590
k₆= −65.746
k₇= 2500.29
[0033]
The superheated steam index value deriving unit 84 will be described. The superheated steam index value deriving unit 84 calculates the gauge pressure of the superheated steam detected by the superheated steam pressure sensor 6 as P.₂(MPaG), the index value a for the coefficient is the superheated steam pressure P₂Is obtained by a linear expression for deriving the index value for the coefficient of the following formula 9, and the index value b for the constant term is determined from the pressure P of the superheated steam.₂Is obtained by the following linear expression for deriving the index value for the constant term of the following ten.
[0034]
[Equation 9]
a = k₈× P₂+ K₉
[0035]
[Expression 10]
b = k_Ten× P₂+ K₁₁
k₈, K₉, K_Ten, K₁₁Is a constant, and is set as follows, for example.
k₈= 0.1702
k₉= 0.47625
k_Ten= -44.464
k₁₁= 591.625
[0036]
The superheated steam enthalpy deriving means 85 will be described. The superheated steam enthalpy deriving means 85 uses the superheated steam enthalpy i2 (kJ / kg), the coefficient index value a as the superheated steam temperature T (° C) as a variable. The following equation 11 is used to obtain the superheated steam enthalpy derivation using the constant term index value b as a constant term.
[0037]
## EQU11 ##
i2 = 4.18605 × (a × T₂+ B)
[0038]
The dryness deriving means 86 calculates the dryness x of the wet steam based on the enthalpy i1 of saturated water, the latent heat of evaporation r1 of saturated water and the enthalpy i2 of superheated steam obtained as described above. 5 is obtained.
[0039]
The operation unit 9 is configured to be able to command freely what to measure from the enthalpy i1 of saturated water, the latent heat of vaporization r of saturated water, the enthalpy i2 of superheated steam, and the dryness x of wet steam. The processing unit 8 functions to measure what is instructed from the operation unit 9 and causes the display unit 10 to display the measurement result.
[0040]
That is, when the measurement of the saturated water enthalpy i1 is commanded, the wet steam index value deriving means 81 and the saturated water enthalpy deriving means 82 are operated to measure the saturated water enthalpy i1, and the measured saturated water enthalpy is measured. When i1 is displayed on the display unit 10 and the measurement of the saturated water evaporative latent heat r is commanded, the wet steam index value deriving unit 81 and the saturated water evaporating latent heat deriving unit 83 are activated, and the saturated water evaporating latent heat r is obtained. The measured latent heat of vaporization r of the saturated water is displayed on the display unit 10.
Further, when the measurement of the superheated steam enthalpy i2 is commanded, the superheated steam index value deriving means 84 and the superheated steam enthalpy deriving means 85 are operated to measure the superheated steam enthalpy i2, and the measured superheated steam enthalpy i2 is measured. i2 is displayed on the display unit 10.
When the measurement of the wet steam dryness x is commanded, the wet steam index value deriving means 81, the saturated water enthalpy deriving means 82, the saturated water evaporation latent heat deriving means 83, the superheated steam index value deriving means 84, the superheated steam enthalpy. The deriving unit 85 and the dryness deriving unit 86 are operated to measure the dryness x of the wet steam, and the measured dryness x is displayed on the display unit 10.
[0041]
According to the wet steam dryness measuring apparatus configured as described above, it is possible to continuously measure the enthalpy i1 of saturated water, the latent heat of evaporation r of saturated water, the enthalpy i2 of superheated steam, and the dryness x of wet steam. Is possible.
[0042]
[Another embodiment]
Next, another embodiment will be described.
(A) In the above embodiment, the embodiment of the wet steam dryness measuring device has been described. Hereinafter, based on FIG. 1, the saturated water enthalpy measuring device, the saturated water evaporation latent heat measuring device, and Each embodiment of the enthalpy measuring device for superheated steam will be described.
The saturated water enthalpy measuring device includes the measuring steam supply path 1, the wet steam pressure sensor 5, the processing unit 8, the operation unit 9, and the display unit 10 among the wet steam dryness measuring devices described in the above embodiment. The processing unit 8 includes wet steam index value deriving means 81 and saturated water enthalpy deriving means 82.
[0043]
The saturated water evaporative latent heat measuring device includes the measuring steam supply path 1, the wet steam pressure sensor 5, the processing unit 8, the operation unit 9, and the display unit among the wet steam dryness measuring devices described in the above embodiments. The processing unit 8 includes a wet steam index value deriving unit 81 and a saturated water evaporation latent heat deriving unit 83.
[0044]
The superheated steam enthalpy measuring device includes the measuring steam supply path 1, the adiabatic expander 2, the steam discharge path 3, the flow rate adjusting valve 4, the superheated steam among the wet steam dryness measuring apparatuses described in the above embodiment. The pressure sensor 6, the superheated steam temperature sensor 7, the processing unit 8, the operation unit 9, and the display unit 10 are configured. The processing unit 8 includes a superheated steam index value deriving unit 84 and a superheated steam enthalpy deriving unit 85.
[0045]
(B) In the above embodiment, a quadratic polynomial is set as the nth-order equation for deriving saturated water enthalpy and the nth-order equation for deriving saturated water evaporation latent heat, respectively. A third or higher order polynomial may be set. However, since a first-order polynomial has a large error, it is preferable to set it to a second-order or higher polynomial.
[0046]
(C) The saturated water enthalpy i1 is artificially calculated by the equation for deriving the wet steam index value expressed by the above equation 6 and the secondary equation for deriving the saturated water enthalpy expressed by the equation 7 above. You may ask.
The saturated water evaporative latent heat r is obtained by artificially calculating by the above equation for deriving the wet steam index value expressed by Equation 6 and the secondary equation for deriving the saturated water evaporative latent heat expressed by Equation 8. May be.
The enthalpy i2 of the superheated steam is defined as the linear expression for deriving the index value for the coefficient represented by the above formula 9, the primary formula for deriving the index value for the constant term represented by the formula 10, and the superheated steam represented by the formula 11. It may be obtained by artificial calculation using a linear expression for enthalpy derivation.
You may obtain | require the dryness x of wet steam by calculating artificially as follows. That is, as described above, the enthalpy i1 of saturated water, the latent heat of evaporation r1 of saturated water, and the enthalpy i2 of superheated steam are calculated, and the enthalpy i1 of saturated water, the latent heat of evaporation r of saturated water, and the enthalpy i2 of superheated steam are calculated. Based on the above, the dryness x of the wet steam is obtained by the above equation (5).
[0047]
(D) Constant k₁, K₂, K_Three, K_Four, K_Five, K₆, K₇, K₈, K₉, K_Ten, K₁₁The specific values are not limited to the values exemplified in the above embodiment, and can be set in various ways so that each value for the derivation purpose can be obtained with high accuracy. For example, when the wet steam dryness is divided into a plurality of ranges of 0 to 100% and each constant is set so that the dryness can be measured accurately for each range, It becomes possible to further improve the measurement accuracy of the dryness.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a wet steam dryness measuring apparatus according to an embodiment of the present invention.
[Explanation of symbols]
2 Adiabatic inflator
5 Wet steam pressure detection means
6 Superheated steam pressure detection means
7 Superheated steam temperature detection means
81 Wet steam index value deriving means
82 Means for deriving saturated water enthalpy
83 Means for deriving latent heat of saturated water evaporation
84 Superheated steam index value deriving means
85 Deriving means for superheated steam enthalpy
86 Dryness derivation means

Claims (8)

  The wet steam index value is obtained by multiplying the fourth root of the absolute pressure of the wet steam to be measured by a coefficient, and the saturated water enthalpy i1 is calculated by the nth-order equation for deriving the saturated water enthalpy using the wet steam index value as a variable. How to measure enthalpy of saturated water. Wet steam pressure detecting means for detecting the pressure of the wet steam to be measured;
Wet steam index value deriving means for obtaining the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam by a coefficient based on the detection information of the wet steam pressure detecting means;
A saturated water enthalpy measuring device provided with saturated water enthalpy deriving means for obtaining an enthalpy i1 of saturated water by an n-order equation for deriving saturated water enthalpy using the wet steam index value as a variable.   Calculate the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam to be measured by a coefficient, and use the nth-order equation for deriving the saturated water evaporation latent heat with the wet steam index value as a variable. A method for measuring the latent heat of evaporation of saturated water to obtain r. Wet steam pressure detecting means for detecting the pressure of the wet steam to be measured;
Wet steam index value deriving means for obtaining the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam by a coefficient based on the detection information of the wet steam pressure detecting means;
An apparatus for measuring latent heat of evaporation of saturated water, comprising: saturated water evaporation latent heat deriving means for obtaining saturated water evaporation latent heat r by an n-order equation for deriving saturated water evaporation latent heat using the wet steam index value as a variable.   A linear expression for deriving an index value for a constant term using a primary expression for deriving an index value for a coefficient with the pressure of the superheated steam to be measured as a variable, and deriving an index value for the constant term using the pressure of the superheated steam to be measured as a variable The index value for the constant term is obtained by a linear expression for deriving superheated steam enthalpy using the index value for the coefficient as the coefficient of the term with the temperature of the superheated steam as a variable and the index value for the constant term as the constant term. The method for measuring the enthalpy of superheated steam to obtain the enthalpy i2 of superheated steam. Superheated steam pressure detecting means for detecting the pressure of the superheated steam to be measured, and superheated steam temperature detecting means for detecting the temperature are provided,
Based on the detection information of the superheated steam pressure detecting means, a coefficient index value is obtained by a linear expression for deriving a coefficient index value using the superheated steam pressure as a variable, and a constant using the superheated steam pressure as a variable Superheated steam index value deriving means for obtaining an index value for a constant term with a linear expression for deriving an index value for a term;
Based on the detection information of the superheated steam temperature detecting means, the coefficient index value is a coefficient of a term having the temperature of superheated steam as a variable, and the primary for deriving superheated steam enthalpy having the constant term index value as a constant term The superheated steam enthalpy measuring device provided with the superheated steam enthalpy deriving means for obtaining the enthalpy i2 of the superheated steam by the equation. The wet steam index value is obtained by multiplying the fourth root of the absolute pressure of the wet steam to be measured by a coefficient, and the saturated water enthalpy i1 is calculated by the nth-order equation for deriving the saturated water enthalpy using the wet steam index value as a variable. Determining the evaporation latent heat r of saturated water by the nth order equation for deriving the latent heat of saturated water evaporation using the wet steam index value as a variable,
Obtain a coefficient index value by a linear expression for deriving a coefficient index value using the pressure of the superheated steam generated by adiabatic expansion of the measurement target wet steam as a variable, and a constant term using the pressure of the superheated steam as a variable The index value for the constant term is obtained by a linear expression for deriving the index value for the index, the index value for the coefficient is used as a coefficient of a term whose temperature is the temperature of the superheated steam, and the index value for the constant term is used as the constant term Obtain the enthalpy i2 of the superheated steam using the primary equation for enthalpy derivation
Based on the enthalpy i1 of the saturated water, the latent heat of vaporization r of the saturated water and the enthalpy i2 of the superheated steam, the dryness x of the wet steam is expressed as follows:

Method for measuring dryness of wet steam obtained by Wet steam pressure detecting means for detecting the pressure of the wet steam to be measured;
An adiabatic expander that adiabatically expands the wet steam to be measured into superheated steam;
Superheated steam pressure detecting means for detecting the pressure of the superheated steam generated by the adiabatic expander;
And a superheated steam temperature detecting means for detecting the temperature of the superheated steam,
Wet steam index value deriving means for obtaining the wet steam index value by multiplying the fourth root of the absolute pressure of the wet steam by a coefficient based on the detection information of the wet steam pressure detecting means;
Saturated water enthalpy derivation means for obtaining an enthalpy i1 of saturated water by an n-order equation for deriving saturated water enthalpy using the wet steam index value as a variable;
Saturated water evaporation latent heat deriving means for obtaining saturated water evaporation latent heat r by an nth-order equation for deriving saturated water evaporation latent heat with the wet steam index value as a variable;
Based on the detection information of the superheated steam pressure detecting means, a coefficient index value is obtained by a linear expression for deriving a coefficient index value using the superheated steam pressure as a variable, and a constant using the superheated steam pressure as a variable Superheated steam index value deriving means for obtaining an index value for a constant term with a linear expression for deriving an index value for a term;
Based on the detection information of the superheated steam temperature detecting means, the coefficient index value is a coefficient of a term having the temperature of superheated steam as a variable, and the primary for deriving superheated steam enthalpy having the constant term index value as a constant term The superheated steam enthalpy deriving means for obtaining the superheated steam enthalpy i2 according to the equation is provided,
Based on the enthalpy i1 of the saturated water, the latent heat of vaporization r of the saturated water and the enthalpy i2 of the superheated steam,

The wet steam dryness measuring device is provided with a dryness deriving means for obtaining the dryness x of the wet steam.

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