Method for operating a circulation system, and circulation system

Abstract

The invention relates to a method for operating a circulation system comprising a cooling device with an input port and an output port for cooling water. The invention also relates to a circulation system for implementing said method.

Claims

1. A circulation system comprising: a cooling device for cooling water, the cooling device comprising: an input port, an output port, and wherein the cooling device is configured to identify water temperature at the input port and the output port and to produce water at a set temperature value (T.sub.a) at the output port; a branched pipeline system in fluid communication with the input port and output port of the cooling device, the branched pipeline system comprising: pipe units, comprising at least one single supply line connected to a tapping point, at least one circulation conduit, and at least one flow pipe, wherein the at least one flow pipe comprises at least one of a collective feed line, a riser line, and a building floor line, more than one node, wherein each of the pipe units are connected together through one of the nodes, one or more partial sections thermally coupled to a surrounding, the partial sections comprising one or more pipes units, wherein each partial section further comprises an initial region and end region and wherein each partial section is connected to at least one node proximate at least one of the initial region and the end region; and wherein, for a given apportionment of a volume of water flow emerging from any specified node into one of the pipe units, a mixed water temperature is determinable based on the water flow from the one or more pipe units entering the specified node; a circulation pump in fluid communication with at least one of the pipe units of the branched pipeline system, wherein the circulation pump is configured to provide a particular volumetric rate of water flow (V.sub.z) at the input port of the cooling device and provide water flow through the at least one circulation conduit when water is not being removed through a tapping point; and a regulator, wherein the regulator is configured to formulaically determine a partial section temperature change of water between the initial region and end region of each of the one or more partial sections, and wherein the regulator is also configured to formulaically determine and operationally set the set temperature value (T.sub.a) and the particular volumetric rate of water flow (V.sub.z) such that the water temperature proximate the end region of the one or more partial sections (T.sub.ME) and the water temperature at the input port of the cooling device (T.sub.b) is less than a target temperature (T.sub.soll) and any difference between T.sub.soll and T.sub.b is less than a positive given value (θ).

2. The circulation system of claim 1, wherein the regulator formulaically determines the set temperature value (T.sub.a) and volumetric rate of water flow (V.sub.z) through iterative approximation based on a determined temperature for each of the end region of one or more partial sections (T.sub.ME) initially utilizing a temperature start value (T.sub.MA*) and a volume rate flow start value (V.sub.z*) for the output port of the cooling device.

3. The circulation system of claim 1, wherein the one or more partial sections are thermally coupled to the surrounding through a uniform design along their length between the initial region and end region thereof.

4. The circulation system of claim 1, wherein the pipe units further comprise at least one loop line connected to and in fluid communication with the at least one flow pipe.

5. The circulation system of claim 1, wherein the at least one circulation conduit is connected to and in fluid communication with the at least one flow pipe.

6. The circulation system of claim 4, wherein the at least one circulation conduit is connected to and in fluid communication with the at least one loop line.

7. The circulation system of claim 1, wherein the at least one flow pipe comprises at least one riser line and at least one building floor line.

8. The circulation system of claim 1, wherein the at least one flow pipe comprises a collective feed line connected to a water supply network through a junction.

9. The circulation system of claim 8, wherein the junction is connected to at least one of a connection line and a consumer line.

10. The circulation system of claim 1, further comprising at least one flow divider disposed in at least one of the at least one flow pipe and at least one loop line.

11. The circulation system of claim 1, wherein the cooling device is thermally coupled to a device selected from the group consisting of a cold generator, a heat pump, a water chiller, or a cold supply network.

Description

(1) The drawings show exemplary embodiments in the specification. The drawing, the specification, and the claims contain many features in combination. The skilled person will also advisedly consider the features individually and combine them into further meaningful combinations.

(2) There are shown, as an example:

(3) FIG. 1: in schematic representation, a circulation system according to the invention

(4) FIG. 2: a further embodiment of a circulation system according to the invention

(5) FIG. 3: a further embodiment of a circulation system according to the invention, in which a further heat exchanger is provided

(6) FIG. 4: a further embodiment of a circulation system according to the invention

(7) FIG. 5: a further embodiment of a circulation system according to the invention

(8) FIG. 6: a further embodiment of a circulation system according to the invention

(9) FIG. 7: a further embodiment of a circulation system according to the invention

(10) FIG. 8: a further embodiment of a circulation system according to the invention

(11) The circulation systems represented in FIGS. 1 to 8 are merely examples, the invention not being limited to these systems. In all the systems shown, exactly two volume flows enter a node and one volume flow departs from it, or exactly one volume flow enters and exactly two volume flows depart from it, as in the case of a T-piece. However, the invention is not limited to systems with such nodes. Basically, all of the lines represented between nodes and between nodes and input port, as well as nodes and output port, may consist of one or more partial sections, as defined above.

(12) Similar components are given the same reference numbers.

(13) In the circulation system represented in FIG. 1, one node K1 is connected across a flow pipe 4a to an output port 12b of a cooling device 12. The cooling device 12 has connections on the refrigeration side and a refrigeration pump 13.

(14) At the node K1 there is provided a branching point to a collective line 4, a connection line to a junction 1 at a water supply network and a consumer line 3, the latter and the connection line not being part of the circulation system. Therefore, no volume flow apportioning occurs at the node K1.

(15) The collective feed line 4 is connected to a riser pipe 5, which empties into a node K2. The node K2 branches into a building floor line 6 and a riser pipe 5, which empties into a node K3 and at which there occurs a branching to a building floor line 6 and a riser pipe 5, [which] is connected to a building floor line 6, which empties into a node K4. The node K2 is connected by a building floor line 6 to a node K6. The node K3 is connected by a building floor line 6 to a node K5.

(16) Two partial sections TS1 and TS2, explicitly characterized as such, are connected across the node K4, TS1 representing a partial section of the building floor line 6 and TS2 representing a circulation conduit.

(17) Moreover, at node K4 there occurs a branching across a single supply line 7 to a tapping point 9. To simplify matters, the single supply lines and tapping points connected to the nodes K2 and K3 are not given reference numbers. Since the circulation system according to the invention is operated in order to carry out the method according to the invention in a state in which no water removal occurs, the nodes which are coordinated with the tapping points are not considered in the following and, accordingly, not given reference numbers in the drawings, except for node K4.

(18) The partial section TS2 is connected to a vertical circulation conduit 10a, which empties into the node K5. The node K5 is connected to a circulation conduit 10a, which empties into the node K6. The node K6 is connected to a vertical circulation conduit 10a, which is connected to a horizontal circulation conduit 10a, which in turn is connected across a vertical circulation conduit to the circulation pump 10b.

(19) The circulation system represented in FIG. 2 has a similar structure to the system of FIG. 1, but loop lines are provided in the building floor lines 6, and to simplify matters a reference number 8 is used only for the uppermost loop line represented in FIG. 2. The loop line 8 is coordinated with an optional flow divider 8a. Loop lines are coordinated with nodes K21 to K32.

(20) It is understood that such systems in which only one loop line is present are also covered by the invention.

(21) FIG. 3 shows another system with nodes K31 to K34, but here the circulation conduits 10a emptying into the nodes K34 and K35 are led in parallel with the building floor lines 6 departing from the nodes K32 and K33.

(22) Moreover, an optional decentralized cooling device 14 with an input port 14a and an output port 14b is arranged in the uppermost building floor line 6, while to simplify the representation the existing junctions of a cold-side circuit and a corresponding pump are not shown.

(23) Similarly, further decentralized cooling devices can be arranged in the other building floor lines.

(24) In another embodiment similar to FIG. 3, the heat exchanger 12 may be omitted; in this case, one cooling device 14 or multiple cooling devices 14 are necessary.

(25) Similar to the embodiment of FIG. 3, cooling devices can be provided in the riser pipes 5 and the building floor line of the embodiments of FIGS. 1, 2 and 4 to 8.

(26) FIG. 4 shows a system with nodes K41 to K51 as in FIG. 3, but loop lines 8 are provided in the building floor lines.

(27) FIG. 5 shows a system with nodes K51 to K55, in which circulation conduits 10 are led in parallel with the riser pipes 5 connected to the nodes K52, K53.

(28) FIG. 6 shows a system with the nodes K61 to K69b, where loop lines are provided between the nodes K63, K64, K66, K67 and K68, K69.

(29) FIG. 7 shows a system with the nodes K71 to K75, where riser pipes 5 are connected to the nodes K72 and K73.

(30) FIG. 8 shows a system with nodes K81 to K89b similar to FIG. 7, but with loop lines arranged between the nodes K89a, K89b, K88, K89 and K84 and K85.

(31) The embodiments represented in the clean drawings under FIGS. 1, 3, 5, 7 can also allow only partial regions to have a circulation. Thus, the partial sections may also represent installations in dwellings, for example, which are not permitted to circulate together on account of different requirements (account metering of the water consumption). A water exchanging to maintain the desired temperature could be possible here with automatic flushing.

(32) The method according to the invention is implemented in the systems of FIGS. 1 to 8 in the above-described manner: starting from a temperature start value T.sub.MA*<T.sub.soll and a volume flow start value V.sub.z* for the first partial section connected to the output port (12b), a temperature change of the water between the initial region and the end region is determined according to a model of the temperature change.

(33) Moreover, a temperature change of the water between the initial region and the end region for each further given partial section is determined according to the model of the temperature change, under the boundary condition that the water temperature in the initial region of the given partial section is equal to the water temperature in the end region of the partial section to which the given partial section is connected.

(34) Preferably, one uses the above-described model of the axial temperature change, according to which the water temperature T.sub.ME in the end region of a partial section of length L is calculated by the formula

(35) $T_{\mathrm{ME}}=\left(T_{\mathrm{MA}}-T_{\mathrm{Luft}}\right)*e^{-\epsilon *L}+T_{\mathrm{Luft}}\epsilon =\frac{k_R}{m_M*c_{\mathrm{pm}}}=\frac{k_R}{V_M*P_M*C_{\mathrm{pm}}}$

(36) The value T.sub.a of the water temperature and the value V.sub.z of the volume flow at the output port 12b are chosen such that, in the end region of each partial section of the circulation system, the water temperature is T.sub.ME<T.sub.soll and at the input port 12a the water temperature is T.sub.b<T.sub.soll with T.sub.soll−T.sub.b<θ, where θ>0 is a predetermined value.

(37) It is understood that the circulation pump 10b is not always operated with a constant volume flow, i.e., regardless of whether the port inlet temperature 12a has exactly the setpoint value or even lies below it.

(38) If the port inlet temperature 12a for various reasons should lie at 17° C. for example, where a max. of 20° C. is given, the delivery volume flow of the circulation pump 10b could be reduced. This can be done automatically, for example, under temperature control. As a result, energy savings will be achieved.

(39) Likewise, in such a case the delivery volume flow of the pump 13 can be reduced by temperature control.

(40) If the port inlet temperature for various reasons should lie at 17° C. for example (where a max. of 20° C. is given for example), the flow temperature in the refrigeration circuit could likewise be adjusted. As a result, energy savings would be achieved.

(41) TABLE-US-00006 TABLE 1 Symbol Unit Designation Explanation c.sub.w kJ(kg K) Specific heat Heat for the heating capacity of the of 1 kg of water by water 1K (4.19 kJ/(kg K)) ρ kg/m.sup.3 Density of the Quotient of mass water and volume of water at given temperature α.sub.a W(m.sup.2 K) Outward heat Heat loss of a 1 m.sup.2 transmission surface for a temperature coefficient difference between the surface and air of 1K λD W(m K) Thermal conductivity of the insulation λR W(m K) Thermal conductivity of the pipeline λges W(m K) Thermal insulation conductivity of a structural piece, here a pipeline incl. multilayered $\frac{1}{{\lambda }_{\mathrm{ges}}}$ (m K)W Thermal resistance $\frac{1}{U_R}$ (m K)W Heat transition resistance U.sub.R W(m K) Heat transfer Heat loss of a 1 m coefficient long insulated for the pipe hot water pipe at a temperature difference between the water and the air of 1K d.sub.a mm Pipe outer diameter Outer diameter of a hot water line D mm Pipe outer diameter Outer diameter of an insulated hot water line L m Pipeline length Length of a partial section ϑ.sub.Luft ° C. Air/surrounding temperature Δϑa K Starting temperature Temperature difference difference between surroundings and medium at the start of a partial section ϑ.sub.MA ° C. Medium temperature Temperature of a at start medium at the start of a partial section ϑ.sub.ME ° C. Medium temperature Temperature of a at end medium at the end of a partial section

LIST OF REFERENCE NUMBERS

(42) 1 Connection to a water supply network 2 Connection line 3 Consumer line 4 Collective feed line 5 Riser (down pipe) 6 Building floor line 7 Single supply line 8 Loop line 8a Static or dynamic flow division 9 Tapping point 10 Circulation system 10a Circulation conduit 10b Circulation pump 12 Cooling device 12a Input port 12b Output port 14 Heat exchanger 14a Input port 14b Output port