JPH07296051A - Method for calculating pipe network - Google Patents

Abstract

PURPOSE:To automatically set the initial value of a pipe network at the time of calculating the pipe network by using an energy level method. CONSTITUTION:(a) Based on the total resistance of a route from a supply source node to each node, the nodes of the upstream and downstream sides of each pipe and the pipe on the upstream side of each node are decided. (b) A pipe which is not specified to be the pipe on the upstream side among all the pipes is set to be a most downstream pipe. (c) The order of a node showing the order of each node from the downstream side to the supply node is decided based on the nodes on the upstream and downstream sides of each node by neglecting a most downstream pipe. (d) The pipe network is set to be tree structure by setting the flow rate of the most downstream pipe to be '0', the flow rate of the pipe supplied to the node is specified from the demanding quantity of a node at a terminal, and the flow rate of the pipe on the upstream side is specified, while adding the demanding quantity of each node, to be the initial value of the flow rate of the pipe. (e) The pressure of the supply source node is set. (f) The initial value of the pressure of each node is calculated by using the pressure of the supply source node and the initial value of the flow rate of the pipe. (g) The pipe network is calculated by using the energy grade method through the use of the initial value of the pressure of each node obtained by the process (f).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calculation method for a pipe network.

[0002]

2. Description of the Related Art Conventionally, in water supply business, gas business, etc.
When installing a new pipe or considering stable supply, the flow rate of the pipe network was calculated. Also, in the electric power industry, the electric wire network current was similarly calculated.

Regarding such a pipe network calculation, for example, "Analysis and Design of Water Distribution Pipe, Morikita Publishing, Tetsuo Takakuwa, 1978.
There is a calculation method by the energy level method on page 113, August 1, 2000. In such a pipe network calculation, after setting the initial flow rate of each pipe for the target pipe network, the energy of each node is taken as an unknown and the relationship between the fluid conservation law and the flow rate between pipes for each node is set. Find a solution that satisfies the equation shown.

[0004]

However, since the initial values are set by human intuition, there is a problem that if the initial values are bad, the number of calculations is repeated and the network calculation takes a long time. .

The present invention has been made in view of the above problems, and an object of the present invention is to provide a pipe network calculation method capable of automatically setting an initial value of the pipe network.

[0006]

In order to achieve the above-mentioned object, the present invention provides a pipe network in which at least one source node and a plurality of nodes are connected by a pipe having resistance (a) said supply Determining the upstream node and the downstream node of each pipe and the upstream pipe of each node based on the total resistance of the path from the source node to each node, and (b) in the above process, Making a pipe that is not designated as an upstream pipe a downstream pipe, and (c) ignoring the downstream pipe of the pipe network,
Determining a node order indicating how many downstream nodes each node has with respect to the source node, based on upstream nodes and downstream nodes of each node; The flow rate of the most downstream pipe is set to “0”, the pipe network has a tree structure, the flow rate of the pipe supplied to the node is determined from the demand amount of the end node, and the demand amount of each node is added to the upstream side pipe. Determining the flow rate and setting it as an initial value of the pipe flow rate; (e) setting the pressure of the supply source; and (f) the pressure of each node using the pressure of the supply source and the initial value of the pipe flow rate. Of the pipe network including the step of: calculating an initial value of the pipe network; and (g) performing a pipe network calculation by the energy level method using the initial value of the pressure of each node obtained in the step (f). It is a calculation method.

[0007]

In the present invention, (a) the upstream node and the downstream node of each pipe and the upstream pipe of each node are determined based on the total resistance of the path from the supply source node to each node, and (b) ) In the above step, a pipe that is not designated as an upstream pipe among all pipes is a downstream pipe,
(C) Disregarding the most downstream pipe of the pipe network, and assigning a node order indicating how much downstream each node is with respect to the source node to the upstream node and the downstream node of each node. Based on the side node, (d) the flow rate of the most downstream pipe is set to "0", the pipe network has a tree structure, and the flow rate of the pipe supplied to the node is determined from the demand of the terminal node, While adding the demand of each node, determine the flow rate of the upstream pipe and set it as the initial value of the pipe flow rate.
(E) The pressure of the supply source is set, (f) the initial value of the pressure of each node is calculated using the pressure of the supply source and the initial value of the pipe flow rate, and (g) in the step (f). Pipe network calculation is performed by the energy level method using the obtained initial value of the pressure at each node.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a flowchart of a pipe network calculation method according to an embodiment of the present invention. As a target pipe network, for example, a pipe network as shown in FIG. 5 is taken.

A description will be given below with reference to these figures. Step 100 First, step 100 will be described.

In step 100, the number of nodes NN indicating the number of junction points of the pipe network, the fluid demand q (NN) allocated to each node, the number of pipes PN of the pipe network, the pipe resistance RES (PN) of each pipe, Of the nodes at both ends of the pipe, one node number NPPN1 (PN) arbitrarily determined, the other node number NPPN2 (PN), the fluid supply source node number NF, and the fluid supply source node number NFIX (NF) are set as known numbers. The storage unit to be stored is defined.

NN, PN, N in parentheses in the alphanumeric characters
F indicates that there are NN pieces, PN pieces, and NF pieces of respective data. When there is a demand for fluid in the middle of the pipe, the fluid demand q (N
N) and are added. The pipe resistance R
ES (PN) is fluid pressure P, flow rate Q, specific gravity P,
Assuming that the pipe inner diameter is D, the extension is L, the parameters are M and N, and the functions are F and G, P ^m = F (Q) · G (P, L,
D) When expressed by Q ^N , it is a value of G (P, L, D) that can be calculated regardless of the flow rate Q.

In the case of the pipe network shown in FIG. 5, NN = 10, PN
= 13, NF = 2, and a node number is assigned to each node. Furthermore, each pipe is also numbered, and the resistance of each pipe is calculated in advance. In the case shown in FIG. 5, node numbers from "1" to "10" are assigned,
A pipe number from "1" to "13" is assigned to each pipe.

FIG. 2 is a diagram showing one node number NPPN1 (PN) and the other node number NPPN2 (PN) which are arbitrarily defined among the nodes at both ends of the pipe.

In FIG. 2, A indicates a pipe number, there are nodes at both ends of the pipe, and the number in the node is the node number. C indicates the resistance of the pipe. Here, if one node is “9” for the pipe 13, the other node is “2”, and NPPN1 (13) = 9, NP
PN2 (13) = 2.

In FIG. 5, since the nodes "1" and "4" are fluid supply source nodes, the number of fluid supply source nodes NF = 2, and the fluid supply source node number NFLX.
(1) = 1 and NFLX (2) = 4.

FIG. 3 defines the demand quantity, and shows that the demand quantity of the node "2" is q (2). This demand will be described with reference to FIG. Step 200 Next, step 200 will be described. Step 20
0 defines a storage unit for storing unknowns.

That is, in step 200, the upstream pipe number IPIPE (N
N), the total resistance SD (NN) from the fluid source, the node order LEVEL (NN) from the fluid source, and the upstream node number NPPN1 (N) given to the pipe.
P), the downstream node number NPPN2 (NP) and the initial flow rate QN (NP), the number of loops LN, and the storage unit for storing the values of the most downstream pipe LOOP (LN) are defined.

As shown in FIG. 4, the upstream pipe IPIP
E shows the pipe of the route with the least resistance from the fluid source. For example, pipe numbers "1", "2", "1"
When the pipe “1” is selected from the pipes in “3” and is set as the upstream pipe, IPIPE (2) = 1.

The total resistance SD (NN) from the fluid source is
For each node, it is the smallest of the sum of the pipe resistances RES of the plurality of paths from the fluid supply source to this node.

Node order LEVEL from fluid source
(NN) indicates how downstream each node is from the fluid supply source.

In the upstream node number NPPN1 (NP) and the downstream node number NPPN2 (NP), the node having the smaller total resistance SD from the fluid supply source is connected to the upstream pipe NPP.
N1 and the larger one is the downstream pipe NPPN2.
For example, in FIG. 2, the node "9" is replaced by the node "5".
If SD is small, NPPN1 (13) = 9 and N
PPN2 (13) = 2.

The initial flow rate QN (NP) is an initial value of the flow rate when each pressure is obtained when the pipe network is calculated.

LN is a parameter, the most downstream pipe LOOP
(LN) is a pipe number determined by this embodiment. Step 300 Next, step 300 will be described. Step 30
0 calculates the total resistance SD from the source of each node,
The upstream node number NPPN1, the downstream node number NPPN2 of each pipe, and the upstream pipe number IP of each node
This is a process of determining the IPE.

The process of step 300 will be briefly described with reference to FIGS. 8 and 9. FIG. 8A shows a change in the node relation data, and FIG. 8B shows a change in the pipe relation data.

In FIG. 8A, the upstream pipe number IPIPE is provisionally set for each node. In this case, since the nodes “1” and “4” are supply source nodes, the upstream pipe number is not determined. Then, for example, "100" is given to each node except the supply source node as an initial value of the total resistance SD. Next, the total upstream resistance SD is calculated based on the upstream pipe number of each node and the resistance of each pipe.

For example, in FIG. 5, the upstream pipe of the node "5" is "4", the upstream pipe of the node "6" is "7", and the resistances RES of the pipes "4" and "7".
Are "20" and "15", respectively, so the upstream total resistance SD of the node "6" is "35 (= 20 + 15)".
Becomes In this way, the upstream total resistance SD of the nodes other than each supply source node is calculated.

Next, as shown in FIG.
Considering the node set in (a) and its upstream pipe number, the upstream node number NPPN1 and the downstream node number NPPN2 are determined for each pipe. For example, in FIG.
From (a), the upstream pipe of the node "6" is pipe "7".
Therefore, in FIG. 8B, the upstream node number of the pipe “7” is “5” and the downstream node number of the pipe “7” is “6”. If the upstream node number and the downstream node number cannot be determined due to the relationship between the node number and the upstream pipe number in FIG. 8A, the upstream node number and the downstream node number are provisionally determined. Thus, for each pipe, the upstream node number NPPN1 and the downstream node number N
Calculate PPN2.

Next, the upstream total resistances SD (1) and SD (2) of the upstream node and the downstream node calculated in FIG. 8 (b) for each pipe are shown in FIG. 8 (a). Obtained and compared, if SD (1) ≦ SD (2),
SD without changing the upstream and downstream node numbers
If (1)> SD (2), the node numbers on the upstream side and the downstream side are exchanged. For example, since the upstream side node and the downstream side node of the pipe with the pipe number “2” are the node “2” and the node “3”, respectively, FIG.
Read the upstream total resistance SD (1) = 10 of the node “2” and the upstream total resistance SD (2) = 21 of the node “3” from
Since SD (1) ≦ SD (2), the upstream node number and the downstream node number are not exchanged for the pipe “2”.

On the other hand, the upstream node and the downstream node of the pipe with the pipe number "3" are the node "3" and the node "4", respectively. The upstream total resistance SD (1) = 21 and the upstream total resistance SD (2) = 0 of the node “4” are read, and SD
Since (1)> SD (2), the upstream node number and the downstream node number are exchanged for the pipe "3".

As shown in FIG. 8B, the upstream side node and the downstream side node are exchanged for the pipes having the pipe numbers "3", "9" and "11".

Corresponding to this replacement, as shown in FIG. 8A, the total resistance SD from the supply source node is calculated for each node, and when there are a plurality of paths, the maximum of all the resistances is calculated. The upstream pipe of the small path is the upstream pipe, and the total resistance of the path is the upstream total resistance. Figure 8
In the case of (a), the upstream pipe numbers of the nodes "3", "7", and "10" are changed to "3", "9", and "11".

Next, as shown in FIG. 9, the upstream pipe number IPIP for each node is calculated using the node relation data and the pipe relation data in the same procedure as described above.
E and the upstream node number NPPN1 for each pipe
And the downstream node number NPPN2.

FIG. 14 is a flow chart for computer processing of the process shown in step 300.

The value of the total resistance SD from the fluid supply source is temporarily set to a large value that cannot actually occur, for example, "100" (step 301). Next, "0.0" is set to the total resistance SD of the fluid supply source node (step 30).
2). As a result, the column 10 of the total resistance on the upstream side of FIG.
This means that the leftmost number of 3 has been set. Next, the switches ISW1 and ISW2 are set to "0" (step 30
3) The value of the pararouter I for picking up the pipes from "1" in ascending order is set (step 304). The total resistance SD from the fluid supply sources of the upstream node and the downstream node of the I-th parameter is compared, and the upstream node NPP is compared.
A node number having a small SD value and a node number having a large SD value are set in N1 and the downstream node NPPN2, respectively (steps 305, 306, 307).

In the pipe number "1" shown in the pipe number column of FIG. 8B, NPPN1 (1) and NPPN2
Since the node numbers in (2) are "1" and "2", respectively, and the total resistances SD (1) and SD (2) from the supply source of each node are "0.0" and "100", respectively, SD (1) ≤
Since SD (2) is satisfied, NPPN1 (1) and NPPN2 (2) are not replaced in step 306, and the values become "1" and "2", respectively.

When the total resistance SD from the fluid supply source of the downstream node number is "100", the value of ISW is set to 1 (steps 308 and 309). For example, the SD of the node number “2” shown in the column 103 of the total resistance on the upstream side in FIG.
Since (2) is "100", the value of ISW is "1" in this case. A value SDNEW obtained by adding the total resistance SD from the fluid supply source of the upstream node NPPN1 and the resistance RES of the pipe to the total resistance SD from the fluid supply source of the downstream node NPPN2, and the value of ISW2 when SDNEW is small. Is set to "1", the value of SDNEW is stored in the total resistance SD from the fluid supply source of the downstream node NPPN2, and the pipe number I is determined as the value of the upstream pipe IPIPE of the downstream node NPPN2. For example, in this step, when the pipe number of FIG. 8A is “1”, the downstream node number NPPN2 (2) is “2”, and the fluid supply source of the node number “2” of FIG. The total resistance SD (2) from is changed from "100" to "10", and the upstream pipe IPIPE (2) is changed to 1.

Next, by adding 1 to the value of the parameter I and setting it to I, preparation is made for data processing for the next pipe. By comparing the value of parameter I with the number of pipes NN in step 313, step 314
Then, when data processing is not performed for all the pipes, the process proceeds to step 305 to perform data processing for the next pipe, but when data processing is performed for all the pipes, the process proceeds to step 315 and both ISW1 and ISW2 are set to "0". To see if When ISW1 is "1", the total resistance SD to the fluid supply source in the node is "100", that is, the data processing is not completed because the temporary value remains, and ISW2 is "1". At this time, since the value of the total resistance SD from the fluid supply source has changed, it is not known whether or not the data processing is completed. Therefore, the process proceeds to step 303, and the data processing is indicated again.

As described above, as shown in FIG.
The upstream node number NPPN1 and the downstream node number NPPN2 are exchanged with the pipe numbers "3", "9", and "11". Node numbers "2", "3", "5" ...
The upstream IPIPE of "10" and the total resistance SD from the fluid source have been set or changed. In particular, FIG.
In the node number “3” of (a), the data once set or changed in the data processing process of the pipe number “2” is changed again in the data processing process of the pipe number “3”.
Similar re-modifications are also found at node numbers "7" and "10". In the first data processing process (Fig. 8),
Since both ISW1 and ISW2 have been changed to 1 in step 309 and step 312, the process proceeds to the second data processing step (FIG. 9). In the second data processing process, the upstream node number N
PPN1 and the downstream node number NPPN2 change,
By the data processing of steps 310 to 313,
The upstream pipe number IPIPE of the node number "6" changes from "7" to "8", and the total resistance S from the fluid supply source S
D also changes from "35" to "23".

In FIG. 5, the upstream pipe IPIPE of the node "6" changes from the pipe number "7" to "8". In the case of the pipe number “10” in FIG. 9, the upstream node number N
Although the PPN1 and the downstream node number NPPN2 are exchanged, SD is used in steps 310 and 311.
Since NEW ≧ SD (NH), the node relation data is not moved. In the second data processing process, step 312
Since it has passed through only once, ISW2 = 1. Therefore, 3 is determined according to the determination in step 315
Enter the second data processing process. In the third data processing process, there is no data change and the process of step 312 is not performed, so both ISW1 and ISW2 are "0".
In step 316, the day processing process ends.

As described above, according to step 300,
Even if the node number and the pipe number are freely set in the initial stage, the upstream node number NPPN1 and the downstream node number N
It can be seen that PPN2 and upstream pipe number are determined. (Below margin) Step 400 Next, Step 400 will be described. Step 400 is
This is a process of calculating the parameter LN and assigning a pipe not designated as the upstream pipe number as the most downstream pipe.

FIG. 10 is a diagram showing the processing at this time. FIG. 10A shows node relation data.
The upstream pipe number IPIPE calculated for each node in step 300, the total upstream resistance SD, and the node rank level from the supply source are shown, and "99" is given as an initial value of this node rank. Figure 10 (b)
Indicates pipe-related data, and indicates a pipe resistance RES, an upstream node number NPPN1 and a downstream node number NPPN2 for each pipe. FIG. 10C shows the relationship between the loop number and the most downstream pipe number LOOP.

The processing in step 400 is as follows when it is simplified. The upstream pipe number I in FIG.
The pipe specified in PIPE (here, "1",
"3", "4", "8", "9", "6", "12",
The sign of the pipe resistance RES of "11") is made negative as shown in FIG. 11B, and the pipes ("2" and "5" here that are not specified in the upstream pipe number IPIPE of FIG. 10A). , "7", "10", "13") are the most downstream pipes, and the most downstream pipe number LOOP is associated with the loop number as shown in FIG. 10 (c).

FIG. 15 is a flow chart when the processing of step 400 is processed by computer.

The parameter N is set to "1", and preparations are made for data processing in ascending order of the node numbers "1" to "NN" (step 401). Next, the node whose total resistance SD from the fluid supply source is “0” is not processed,
For a node for which the total resistance SD is not "0", the resistance value RES of the upstream pipe of the node is made negative and LEVEL of the node is set to "99" (steps 402 and 403). The numerical value "99" means a large numerical value that is not possible in practice, and need not be "99". Step 5 for the meaning of LEVEL
00 will be described later. The provisional numerical value “99” is set in LEVEL in step 400 because the preprocessing of the next step 500 is executed in step 400 together with other processing. In step 403, the pipe resistance is replaced with a negative number, but the pipe number specified in the upstream pipe is marked so that it can be identified. Instead of using a negative number, a flag is added to the total number of pipes NN. You may prepare.

Next, "1" is added to the parameter N to prepare for the data processing of the next node number (step 40).
4). The process returns to step 402 until the data processing of all the nodes is performed in step 405, and when the data processing of all the nodes is completed, the process proceeds to step 406. As a result of the data processing in steps 401 to 405, FIG.
LEVEL of (a) and pipe resistance R of FIG.
Data changes like ES. In steps 406 to 410, the values of the pipe resistance RES of the pipe numbers “1” to “NP” are sequentially inspected, the number of positive pipes is counted, and the pipe number is set to the most downstream pipe number LOOP.

Parameter L defined in step 200
N means the number of unknown flow rates. Step 40
By the data processing of 6 to step 410, FIG.
As described above, the most downstream pipe number LOOP is obtained corresponding to the number. Step 500 Next, step 500 will be described. Step 50
0 is a process of determining the node rank LEVEL from the supply source using the upstream node number NPPN1 and the downstream node number NPPN2 of each pipe.

The process of step 500 will be briefly described with reference to FIG.

This process is a process for calculating the node order indicating the order of each node from the supply source node in the pipe network in which the most downstream pipe determined in step 400 is removed.

As shown in FIG. 6, in the target pipe network, the pipe designated as the most downstream pipe in step 400 is indicated by a broken line. The numbers in the triangles in the figure indicate the order of nodes from the supply source. Source node "1", "4"
Has a node rank of "1". The node order of the nodes “2”, “5”, and “9” on the downstream side of the supply source node “1” is “2”.

The node order of the downstream side nodes "3" and "8" of the supply source node "4" is "2". Furthermore, the node order of the nodes “7” and “10” on the downstream side of the node “8” is “3”. Further, the node order of the node "6" on the downstream side of the node "7" is "4".

In this way, the node rank of each node is determined.

FIG. 11 and FIG. 12 show data changes of the node relation data and the pipe relation data in the processing of step 500.

In FIG. 11A, the node "1",
Since "4" is a source node, the node order LEVEL from the source is changed from "99" to "1".

Next, the nodes "2", "3", "5",
Since "8" and "9" are on the downstream side of the nodes "1" and "4", the node order LEVEL can be changed from "99" to "2".

Similarly in FIG. 12, the node rank from the supply source is calculated for each node.

FIG. 16 is a flow chart when the processing of step 500 is processed by computer.

In steps 501 to 504, the node order LEVEL of the fluid supply source node is set to "1". In step 505, the pipe number is sequentially from "1" to "N".
The parameter I which is designated in ascending order up to "P" is set to "1" and the ISW is set to "0". Step 51
When the ISW is changed to "1" in 3, it is possible that the data processing has not been completed, so the processing returns to step 505 and data processing is performed again. In steps 506 to 511, the pipe resistance RES
Since the value exceeding "0" is the most downstream pipe, the process jumps to step 511 without performing any data processing. When the pipe resistance RES is negative, the downstream node N of the pipe number I
Node order LEVE from PPN2 (2) fluid source
L is "99" and the upstream node NPPN of the pipe
Only when the node rank LEVEL from the fluid source of 1 (2) is not “99”
While changing the value of W to "1", the pipe resistance RES
Is negative, the value is returned to positive, and the value obtained by adding "1" to the node rank LEVEL from the fluid supply source of the upstream node NPPN1 (2) is added to the downstream node NPP.
Set to node order LEVEL from N2 (1) fluid source. This is repeated by the number NP of pipes in steps 511 to 512. In step 513,
If the data has changed in step 510, ie, I
When SW = 1, there is a possibility that the node order LEVEL from the fluid supply source of all the nodes has not been determined, so the process returns to step 505 and the calculation is repeated.

As shown in FIG. 11 described above, except that the node order LEVEL from the supply source of the node number "6" is "99" in the first data processing, the supply from other node's supply source is performed. The node order is set. As shown in FIG. 12, in the second day processing, the node rank LEVEL from the supply source of the node number “6” is set to “4” at step 510 and the ISW is also changed to “1”. It Therefore, the process proceeds to the third data processing by step 513. Since the step 510 is not performed in the third data processing, the ISW is held at "0", and the judgment of the step 513 leads to the end of the step 514. Step 600 Next, step 600 will be described. Step 60
0 means that by setting the flow rate of the most downstream pipe to "0",
This is a process in which the pipe network is used as a tree structure to provide an initial value for the flow rate.

The process of step 600 will be briefly described with reference to FIG. In FIG. 7, the flow rate of the most downstream pipe indicated by the broken line is “0”. Demand q for each node
(NN) is given.

In this case, ignoring the most downstream pipe, the nodes "2", "3", "5", "6", "9",
"10" is treated as an end node, and the flow rate of the pipe connected to it is the demand amount of that node. For example, regarding the node "7", the flow rate of the downstream pipe is q (6), and the demand amount of the node "7" is q.
Since it is (7), the flow rate of the pipe on the upstream side of the node “7” is q (6) + q (7). Similarly, the flow rate on the upstream side of the node “8” is q (6) + q (7) + q (8).
It becomes + q (10). In this way, the initial flow rate of the pipe is set.

FIG. 17 is a flow chart when the processing of step 600 is processed by computer.

A storage unit QN (NP) for storing the value of the pipe initial flow rate in step 601 and a flag storage unit QN (NP) for not double counting the fluid demand of each node.
To prepare. Instead of preparing the flag storage unit QN (NP), there is also a method of saving the storage capacity by making the numerical value of the demand amount of the node once added negative. Step 6
In 02, FLAG is set to "0" when adding the flow rate from the upstream side node of the most downstream pipe, and when the flow rate is added from the downstream side node, the FLAG prepared for changing FLAG to "1" is set to "0". Set to. By the steps 604 to 613, the most downstream pipe LOOP
From the upstream node NPPN1 to the upstream pipe IPIPE of the node, and then the upstream node NPP of the pipe.
As in N1, the fluid demand amount of each node is not double counted, and the fluid demand amount is added up to the fluid supply source node. As a means for not performing double counting, the fluid demand amount of each node is once added at step 608 and step 609, and at the same time, the flag QF is changed to 1, so that the fluid demand amount of the node is not added thereafter. When the addition of the flow rate from the upstream side node of the most downstream pipe is completed, since FLAG is “1” in step 612, the process returns to step 604, and FLAG is changed to “0” in step 605, and
The downstream node number of the most downstream pipe is set in the node K of flow rate addition. The procedure of the flow rate addition in the subsequent steps 607 to 611 is the same as when the upstream node number of the most downstream pipe is set. Through steps 613 and 614, the flow rates are repeatedly added by the number of the most downstream pipes. Steps 700 and 800 Next, steps 700 and 800 will be described. Step 700 is a process of inputting the pressure of the supply source node, and step 800 is a process of calculating an initial value of the pressure of each node based on the input pressure of the supply source node.

For example, as shown in FIG. 18, considering the node "1" and the node "2", the node "1"
Is a supply source node and sets a pressure (head value) P ₁ . As described above, the flow rate of the pipe “1” is Q ₁ = q
(2).

Assuming that the pressure (head value) of the node “2” is P ₂ , for example, Q ₁ = S ₁₂ · ΔP = S ₁₂ · (P ₁ −P ₂ ) ^a , where S ₁₂ = 0.27853 C _H · D ^2.63・ L ^-0.54 , a =
0.54 C _H: flow rate counting, D: pipe diameter, L: Since the length of the pipe, P ₂ = P ₁ - a ^{_{(Q 1 / S 12) 1}} / a.

Here, assuming that a = 0.5 in order to simplify the calculation, P ₂ = P _1- (Q ₁ / S ₁₂ ) ² = P ₁ -RES · Q ₁ ² (1) (however, RES = 1 / S ₁₂ ² ) Therefore, if the pressure at the source node is set first,
The pressure at each node can be sequentially obtained using equation (1).

FIG. 19 shows steps 700 and 8
FIG. 13 is a flow chart when the processing of 00 is processed by computer, and FIG. 13 is a diagram showing the pressure value of each node when receiving the processing shown in FIG.

In FIG. 19, "99" is set in the pressure term F of each node (step 801), and P _0i ² is set in the pressure term F of the supply source node (step 802). Therefore, the first pressure is set as shown in FIG.

Next, the resistance RES of the most downstream pipe is set to "9.
9 "is set (step 803), the parameter I indicating the pipe number is set to" 0 ", the flag PF is set to" 0 "(step 804), and I is increased by" 1 "(step 80).
5), I is compared with a parameter N indicating the total number of pipes (step 806). When I is smaller than N, the pipe resistance RES (I) is compared with "99" (step 808). When the pipe resistance RES (I) is smaller than "99", NPPN1 (I) is substituted into K1 and NPPN2 (I) is substituted into K2 (step 809).

Then, F (K1) is compared with "99" (step 810). If F (K1) <"99", then F (K1) <99
(K2) is compared with "99" (step 811), and F
When (K2) = 99, "1" is substituted for PF and F (K
2) = F (K1) + RES · Q (I) ² (step 812).

When I = N in step 806, it is determined whether or not PF = 0 (step 80).
7) If PF is not "0", the process returns to step 804, and if PF = 0, the process ends.

By receiving such processing, FIG.
As shown in 3, the initial value of the pressure at each node is set. In this case, the initial value of the pressure is set by repeating the calculation four times. Step 900 Next, step 900 will be described. Step 90
At 0, the pipe network is calculated by the energy level method using the initial value of the pressure at each node. For the energy level pipe network calculation, refer to "Analysis and design of water distribution pipes, Morikita Publishing,
Tetsuo Takakuwa, August 113, 1978, p. 113 ”, and the details are omitted.

Thus, according to the present embodiment, in setting the initial value of the pressure necessary for calculating the flow rate of the pipe network by using the energy level method and greatly affecting the calculation time, the pipe network is structured as a tree structure. Since the initial value of the pressure is set as, the calculation time can be shortened.

The present invention can be variously modified within the scope of its technical idea. For example, step 10
In the case of 0, the digital mapping data may be processed and edited to prepare, or if the number of nodes is about 50, it may be created by hand.

Further, the present invention can be applied to the calculation of water pipe network, the calculation of gas pipe network, and the calculation of electric wiring network current. In the electric wire network current calculation, it is sufficient to consider the pipe as the wiring and the flow rate as the current.

[0076]

As described above in detail, according to the present invention, when the pipe network is calculated using the energy level method,
The initial value of the pipe network can be set automatically.

[Brief description of drawings]

FIG. 1 is a flowchart showing processing steps for selecting a loop, setting an initial value, and calculating a network according to an embodiment of the present invention.

FIG. 2 is a diagram showing the definition of a pipe

[Figure 3] Diagram showing the definition of demand

FIG. 4 is a diagram showing a node definition

FIG. 5 is a diagram showing a target pipe network in this embodiment.

FIG. 6 is a diagram showing the most downstream pipes and node order.

FIG. 7 is a diagram showing an example of calculating an initial value of a flow rate.

FIG. 8 is a diagram showing the processing of step 300.

FIG. 9 is a diagram showing a process when the number of repetitions of step 300 is 2;

FIG. 10 is a diagram showing the processing of step 400.

FIG. 11 is a diagram showing the processing of step 500.

FIG. 12 is a diagram showing a process in which the number of repetitions of step 500 is two.

FIG. 13 is a diagram showing the processing of steps 700 and 800.

FIG. 14 is a flowchart when the processing of step 300 is computer-processed.

FIG. 15 is a flowchart when the processing of step 400 is computer-processed.

FIG. 16 is a flowchart of a case where the processing of step 500 is processed by a computer.

FIG. 17 is a flowchart when the processing of step 600 is processed by a computer.

FIG. 18 is an explanatory diagram of a pressure calculation method.

FIG. 19 is a flowchart of a case where the processes of steps 700 and 800 are processed by a computer.

[Explanation of symbols]

 A: Pipe number B: Node C: Pipe resistance

Claims (4)

[Claims] 1. A pipe network in which at least one supply source node and a plurality of nodes are connected by a pipe having resistance, (a) based on a total resistance of a path from the supply source node to each node, An upstream node and a downstream node of the pipe, a step of determining the upstream pipe of each node, and (b) a step of making the pipe not designated as the upstream pipe among all the pipes the most downstream pipe in the step, (C) Disregarding the most downstream pipe of the pipe network, and assigning a node order indicating how much downstream each node is with respect to the source node to the upstream node and the downstream node of each node. (D) The flow rate of the most downstream pipe is set to “0”, the pipe network has a tree structure, and the power supply to the node is supplied from the demand amount of the end node. (E) setting the pressure at the supply source node, and determining the flow rate of the upstream pipe while adding the demand of each node, and setting the flow rate of the upstream pipe to the initial value of the pipe flow rate. ) Calculating the initial value of the pressure of each node using the pressure of the supply source node and the initial value of the pipe flow rate; (g) the initial value of the pressure of each node obtained in step (f). A method of calculating a pipe network by using the energy level method using, and a pipe network calculation method comprising: 2. The method of calculating a pipe network according to claim 1, wherein the pipe network is a gas pipe network. 3. The pipe network is a water supply pipe network.
Calculation method of pipe network described in paragraph. 4. The calculation method for a pipe network according to claim 1, wherein the pipe network is a power network, the flow rate is an electric current, and the pipe is a wiring.