JPH0245669A - Pump discharge measuring device for storage pump - Google Patents

Abstract

PURPOSE:To permit an accurate pump discharge to be measured by outputting a pump discharge signal being based on the total head calculated by using a pressure head signal, actual head signal and a residual speed head signal. CONSTITUTION:A pressure head detecting means 12 detects a pressure of delivery water 9 in a pump 1, outputting a pressure head signal 14a. While an actual head detecting means 11 outputs an actual head signal 6a in accordance with the actual head between a pump well 2 and the pump 1. Further a residual speed head arithmetic means 15 outputs a residual speed head signal 17a by arithmetic means 16, 17. Here a main arithmetic means 18, which calculates the total head of the pump 1 by using the input signals 14a, 6a, 17a while performs predetermined calculation being based on the total head calculation result, outputs a pumped storage flow signal 18a in accordance with the total head. Since a pump discharge measuring device 20 is thus constituted, an accurate pump discharge can be obtained from the total head of the pump 1 and a Q-H curve.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention economically measures the pumping flow rate of a pump used in water treatment equipment without using direct flow rate detection means such as a flow rate sensor. Equipment to measure.

In particular, it relates to a device that can perform highly accurate measurements.

[Conventional technology]

FIG. 2 is an explanatory diagram of the configuration of a conventional pumping water flow measuring device 8 of a pumping pump. In the figure, l is a pump that lifts water 3 from pump well 2 to discharge conduit 4, and 5 is the water level H of pump well 2.
, 4 detection 1-” (Water level signal 5a according to this detection result
A pump well water level gauge that outputs.

6 uses the input water level signal 5a to calculate the formula "C (1)" and generates an actual head signal 6a corresponding to the resulting actual head Ho.
α in equation (1) is the height of the discharge port 1a of the pump 1 from the bottom 2- of the pump well 2.

H, = α-H1... (1) In Fig. 2, 7 is the Q of the pump 1, which is obtained in advance when the actual head note 6a is input, as shown in Fig. 3.
- Perform a predetermined calculation using the H curve ``0'' and false *6a 1
A flow rate calculation means that outputs a flow rate signal 7a that calculates the flow rate Q corresponding to the actual head H0 represented by the signal 6a,
Reference numeral 18 is composed of the above-mentioned water level gauge 5 and calculation means 6 and 7, and has a length of 1 inch.

[Problem to be solved by the invention]

The flow rate measuring device [8 is configured as described above and has a temperature of ℃,
According to the flow rate signal 7a, it is possible to measure the flow rate of the discharged water 9 discharged by the pump I without using a flow rate measuring device such as the Sata Narita type and the direct flow rate measuring device, which is economical. It is a pumped water flow rate measuring device with a temperature of ℃, but in this case, the correct head H to be adopted in the calculation in the flow rate calculation means 7 is:
Actual pump head H0 (C1 pump 1 larger than this H8)
Since the total pumping head Ht is , the flow rate represented by the flow rate signal 7a is always smaller than the actual pumping flow rate in the flow value measuring device B, and the problem is that the flow rate measurement result is inaccurate. be. Here, the total head Ht is the water head expressed by the formula (2), and Hp and HV in the formula (2) are the pressure head and residual velocity head in the discharge water 9, respectively.

Ht=H, + Hp+ Hv −−・・−(Zr
An object of the present invention is to use the total head Ht of the pump as the head H used when calculating the pumping flow rate Q from the Q-H curve of the pump, thereby making it possible to accurately measure the pumping flow rate in degrees Celsius. There is a particular thing.

[Means to solve the problem]

In order to achieve the above objects, the present invention provides a pressure head detection means for detecting the pressure of water discharged from a lift pump that lifts water from a pump well and outputting a pressure head signal corresponding to the pressure of the water discharged from the machine. and an actual pump head detection means that detects the water level of the pump well and performs a predetermined calculation based on the detection result, and outputs an actual pump head comment corresponding to the actual pump head between the pump well and the pump. a residual velocity head calculation means which receives a pumped water flow rate signal, performs a predetermined calculation based on the pumped water flow rate signal, and outputs a residual velocity head No. 1 corresponding to the residual velocity of the discharged water; , the actual head signal and the residual speed head No. 1 are input.Using these three input notes, calculate the lift pump head in cm, and perform a predetermined calculation based on the calculation results here. Go 1
A pumped water flow measuring device is configured to output the pumped water flow rate signal corresponding to the total pumping head.

[Effect]

With the above configuration, the main calculation means calculates the correct pumping flow rate from the total head of the pump and the Q-H curve of the pump and outputs a pumping flow rate signal corresponding to this pumping flow rate. , it is possible to perform accurate pumping flow rate measurement.

〔Example〕

FIG. 1 is an explanatory diagram of the configuration of the present invention. In the figure -c, parts having the same functions as those in FIG. 2 are denoted by the same reference numerals as in FIG.

In Fig. 1, u and II consist of a pump water level gauge 5 and an actual head calculation means 6, which detect the water level H1 of the pump well 2 and perform the above calculation based on the detection result of the pump well 2. An actual head detection means 12 outputs an actual head No. 1 6a corresponding to an actual head H0 between the pump 1 and the pump 1, and 12 detects the pressure P of the discharged water 9 at the pump outlet 1ar. The pump discharge pressure gauge 13 outputting the discharge pressure signal 13aY and the discharge pressure signal t3a are subjected to a predetermined calculation τ.
The pressure head detection means includes a pressure head calculation means 14 which outputs a pressure head calculation means 14a representing the pressure head Hp corresponding to the signal 13a. It can be said that it is a means for detecting the pressure P of t and outputting the pressure head signal 14a according to this pressure P.

15 is the flow rate of the discharged water 9, in other words, when the pumped water flow rate signal 18a representing the pumped water flow rate Q of the pump 1 is input, the cross-sectional area of the discharge port 1a of the pump 1 is S, which is shown in equation C (3). The first calculation means 16 performs calculation and outputs a residual velocity signal 16a corresponding to the flow velocity of the discharged water 9 at the °C discharge port 1a, that is, the residual velocity V of the discharged water 9, and the residual velocity note 16a is expressed by the formula t(4). Residual velocity head calculation means 17 includes a second calculation means 17 that outputs a residual velocity head signal 178 representing the residual velocity head Hv corresponding to the τ speed V, which performs the calculation shown in FIG. The device that simultaneously reads each part of the head deviation IJ6a and the residual velocity head signal 17a at every predetermined time interval τ performs the calculations described below, and the main calculation that outputs the pumped water flow rate signal tSa described above according to the calculation results. It is a means. In equation (4), g is the acceleration of gravity.

Q/S=V ・・・・・・(31■/(
2g) = Hv ・Mountain... (a so "C1
The main calculation means 18 includes a total head calculation means 19 which uses each part of the signals Za*Sa and 17a to calculate the formula c('3) and outputs a total head signal 19a representing the total lift aHt;
When a is input.

The above-mentioned pumping flow rate signal 18a representing the flow rate Q corresponding to the head H equal to the total head Ht represented by the 1 signal 19a is obtained by performing the same calculation as in FIG.
It consists of a flow rate calculation means 7 which outputs instead of a.

In FIG. 1, the residual velocity head calculation means 15 and the main calculation means 18 are constructed as described above, so that the calculation means 15 calculates the pumped water flow j! The main calculation means 18 is a calculation means that performs a predetermined calculation based on the signal 18a and outputs a residual velocity head signal 17a corresponding to the residual velocity V of the discharged water 9. signal 14
a, the actual head signal 6a, and the residual velocity head No. 43 17a are input.

It is a calculation means that uses these three input signals to calculate the total head Ht of the pump l, performs a predetermined calculation based on the calculation result, and outputs the pumped water flow rate *18a corresponding to the total lift & H1. Be able to do it. Reference numeral 20 denotes a pumping flow rate measuring device for the pump 1, which includes the above-mentioned king head detection means 12, actual head detection means 11, residual velocity head calculation means 15, and main calculation means 18.

In the flow measuring device 20, each part is configured as described above, so that the residual velocity iV of the discharged water 9 changes slowly over time compared to the time interval τ of the total head calculation calculation performed by the main calculation means 18. When , it is clear that the residual velocity head Hv represented by the signal 17a is approximately equal to the residual velocity head of the discharged water 9 at the time when the main calculation means L8 reads each of the signals @za and sa. However, such residual velocity V
If the change over time is gradual, the total head signal 19a will almost accurately represent the total head Ht of pump l. d can be measured accurately.The above-mentioned time interval τ is generally set to 10 Cms).

〔Effect of the invention〕

As mentioned above, f:1 The odor system of the present invention detects the pressure of the water discharged from the pump f that lifts water from the pump well.
A pressure head detection means outputs a pressure head signal corresponding to the pressure of the discharged water, and a pressure head detection means detects the water level of the pump well and performs a predetermined calculation based on the detection result to determine the actual head height between the pump well and the pump. and an actual head detection means for outputting an actual head signal according to the actual head.

A residual velocity head calculation means receives a pumped water fi amount signal, performs a predetermined calculation based on the pumped water flow rate signal, and outputs a residual velocity head signal corresponding to the residual velocity of discharged water, and a pressure head signal and an actual head signal. The residual speed and water quality signal are input, and these three input signals are used to calculate the total head of the °C pump.
Equipped with main calculation means that outputs a pumped water flow rate signal according to the total head.

A pumping flow rate measurement device for a storage pump was configured to measure the pumping flow rate of the storage pump based on the pumping flow rate signal.

Therefore, with the above configuration, the main calculation means outputs a pumping flow rate signal corresponding to the correct pumping flow rate by calculating the correct pumping flow rate from the total head of the t# water pump and the Q-H curve of the pump. Since this main calculation means can be constructed in a simple manner, the present invention has the advantage of being able to accurately measure the pumped water flow rate.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the configuration of a refreshing embodiment of the present invention, Fig. 2 is an explanatory diagram of the configuration of a pumping flow rate measuring device for a conventional pump, and Fig. 3 is the operation of the main parts in Figs. 1 and 2. It is an explanatory diagram. 1... Lifting pump, 2... Pump well,
3...Water, 6a...Actual head deviation, 9.
...discharge water, 11...actual head detection means, 12...pressure head detection means, 14a...
. . . Pressure head signal, 15 . . . Residual velocity head calculation means, 17a . . . Residual velocity head signal, 18.
...Main calculation means! 8a... Pumped water fi!
Eclipse, 20... Lifting pump pumping flow rate measuring device f
lZ, Ho...Actual head, H1...Pump well water level. P...Pressure, V...Residual velocity.

Claims (1)

[Claims] 1) Pressure head detection means that detects the pressure of water discharged from a pump that lifts water from a pump well and outputs a pressure head signal corresponding to the pressure of this discharge water; and a pressure head detection means that detects the water level of the pump well. an actual head detection means that performs a predetermined calculation based on the result and outputs an actual head signal corresponding to the actual head between the pump well and the lift pump; residual velocity head calculation means for performing a predetermined calculation and outputting a residual velocity head signal corresponding to the residual velocity of the discharged water; and a residual velocity head calculation means for inputting the pressure head signal, the actual head signal and the residual velocity head signal; A main calculation means that calculates the total head of the water pump using three input signals, performs a predetermined calculation based on the calculation result, and outputs the pumped water flow rate signal according to the total head, A pumping flow rate measuring device for a pumping pump, characterized in that the pumping flow rate of the pumping pump is measured based on the pumping flow rate signal.