EP1508013A1

EP1508013A1 - Method and device for transmitting heat energy

Info

Publication number: EP1508013A1
Application number: EP03720011A
Authority: EP
Inventors: Rudolf Hirschmanner
Original assignee: Individual
Current assignee: Htps Hirschmanner KG
Priority date: 2002-05-14
Filing date: 2003-05-13
Publication date: 2005-02-23
Also published as: AU2003225321A1; ATA7352002A; AT412110B; WO2003095920A1

Abstract

The invention relates to a method for transmitting heat energy, wherein the heat energy is transmitted into an inner chamber (3) of a rotating centrifuge via a first heat exchanger (4,4a,4b), in which inner chamber (3) a gaseous energy transfer medium is provided, and wherein the heat is discharged from the centrifuge (2) via a second heat exchanger (5; 5a, 5b). The amount of energy used can be reduced substantially by providing the gaseous energy transmission medium inside the rotor (12) in a state of equilibrium and by radially orienting the heat flow in an outward direction.

Description

Method and device for transferring thermal energy

The invention relates to a method for transferring thermal energy, the thermal energy being introduced via a first heat exchanger into an interior of a rotating centrifuge, in which interior there is a gaseous energy transfer medium, and wherein the heat is removed from the centrifuge via a second heat exchanger.

It is known that thermodynamic cyclic processes make it possible to transport thermal energy from a medium which is at a low temperature to a medium which is at a higher temperature. Such cycles are used for example in cooling devices, heat pumps and the like. However, the supply of energy is necessary to maintain the cycle.

The aim of the present invention is to provide a method and a device with which such a cycle process for heat transport from a low temperature to a higher temperature is possible, the energy used for this being significantly reduced. Such a method can be used on the one hand for cooling and on the other hand for heating similar to a heat pump, if it is possible to extract heat from another medium, such as is the case when geothermal energy is used.

From US 5,226,593 A a method and a device for heating buildings is known, in which a fan is used to generate a warm air flow directed through the building, the energy dissipated by the fan simultaneously contributing to the heating of the medium. The energy consumption of such a heating system does not differ fundamentally from that of an electrical resistance heater and is therefore unacceptably high for many applications. Similar disadvantages also apply to a solution as described in US 4,696,283 A. Furthermore, a device is known from US Pat. No. 3,861,147 A in which thermal energy can be converted into mechanical work by a thermally induced flow in a rotor. A targeted transport of heat is not possible with such a device.

The object of the present invention is to minimize the energy expenditure which is necessary for transporting thermal energy from a state of lower temperature to a state of higher temperature. Another object of the invention is that such a method is simple to carry out and that the required device is inexpensive, feasible and has a simple structure.

According to the invention, the method is characterized in that the gaseous energy transmission medium in the interior of the rotor is in a state of equilibrium and in that the heat flow is directed radially outward.

It is essential to the method according to the invention that very large density differences between the areas near the axis and the areas away from the axis occur in the gas mass in the rotor due to the centripetal acceleration caused by the rotation. Due to these density differences, a temperature gradient is formed, so that in the equilibrium state the temperature in the central area of the rotor is lower than in the area of the circumference. If heat is now supplied inside the rotor, it spreads radially outward through heat conduction and can be dissipated on the outside of the rotor. A continuous heat flow in the rotor can be brought about by continuously supplying heat inside and removing heat outside. Assuming a sufficiently high speed and thus a sufficiently large pressure and temperature difference in the radial direction within the rotor, the heat transfer takes place from a low temperature level to a higher temperature level.

In a particularly preferred embodiment of the method according to the invention it is provided that the temperature of the energy transfer medium increases from the inside to the outside and that the temperature difference of the energy transfer medium between the inner region of the rotor and the outer region of the motor is at least 5 K, preferably at least 50 K, particularly preferably at least 100 K and further particularly preferably at least 200 K. In this way, optimal efficiency can be achieved.

It is particularly advantageous if the heat transport in the rotor takes place primarily by heat conduction. Radiation effects within the energy transfer medium in the rotor can also play a role in the solution according to the invention. The extent of the radiation effects occurring depends essentially on the average temperature level of the geometric design of the rotor, on the type of gas and on the nature of the surfaces of the gas space. However, the highest degree of efficiency is achieved when the thermal conductivity effects dominate. It is essential for the invention, however, that convection currents conditions are largely prevented since they are disadvantageous for the exploitation of the effects according to the invention.

To be particularly favorable, it has been found when the rotor at a speed of more than 8,000 min ^"1, preferably of more than 12,000 ^{min" 1} is operated. In this way, favorable temperature conditions can be achieved with a permissible mechanical load on the rotor. In general, it can be assumed that rotors with larger radial dimensions are operated at lower speeds than rotors with smaller radial dimensions.

A cyclical process in which losses due to transient effects can largely be avoided is achieved in that the rotor is operated at an essentially constant speed.

Furthermore, the invention relates to a device for transferring thermal energy with a rotor, which has an interior space which is filled with a gaseous energy transfer medium, a first heat exchanger being provided in the region of the axis of the rotor and one in the region of the outer circumference of the rotor second heat exchanger is provided, which two heat exchangers are in contact with the gaseous energy transfer medium. According to the invention, the device is characterized in that the gaseous energy transmission medium is in a state of equilibrium in the interior of the rotor.

In a particularly advantageous embodiment variant of the invention, the achievable temperature difference can be increased in that several rotors are provided and that a device for energy transfer from the second heat exchanger of a first rotor to the first heat exchanger of a further rotor is provided. In this context, it is particularly favorable if the first rotor and the further rotor are filled with different energy transmission media. This means that each stage can be optimized for itself depending on the average temperature level within this stage. A mechanically simple structure is achieved in this context in particular by the fact that the rotors are firmly connected to one another.

Thermal losses can be avoided in a particularly preferred manner by accommodating at least one rotor in an insulated protective jacket.

In connection with the invention, the use of a gas with a high molar mass or atomic mass, such as mercury vapor, krypton or argon, has proven particularly useful as an energy transmission medium. The occurrence of undesired convection currents can be prevented within the rotor by appropriate obstacles.

The invention is explained in more detail below on the basis of the exemplary embodiments illustrated in the figures. Show it

Fig. 1 is a schematic representation of a device according to the invention;

Fig. 2 and Fig. 3 diagrams to show the pressure and temperature curve at rest or in operation; and

Fig. 4 is a schematic representation of a rotor of another embodiment of the invention.

The apparatus of Fig. 1 comprises a drive motor 1 and a rotor designed as a centrifugal separator 2, which can be rotated at high speed, for example at 10,000 min ^"1 in rotation. The rotor 2 has an annular inner space 3, in the inside, a first heat exchanger 4 and the outside, a second heat exchanger 5 are located. the radius in respect to the axis la of the apparatus is designated by η, and for the second heat exchanger 5 r _a to the internal heat exchanger 4. in the interior space 3 while a suitable gas is sealed.

The diagram of FIG. 2 shows the pressure and temperature profile of the gas in the interior of the interior 3 in the idle state, ie without rotation. In this state, a constant pressure p ₀ is established in the interior 3, and without the addition or removal of heat via the heat exchangers 4 and 5, a temperature equilibrium is established at the temperature T ₀ , which is shown with a solid line in FIG. 2. If a heat flow is continuously introduced into the rotor 2 via the inner heat exchanger 4 and is dissipated analogously via the heat exchanger 5, a temperature gradient is formed in a known manner, which is shown in accordance with the broken line Ti in the diagram in FIG. 2. The steepness of the temperature gradient depends mainly on the heat flow and the geometry of the rotor 2 and the thermal properties of the gas in the interior 3. The heat flows in a manner known per se from a state of higher temperature to a state of lower temperature.

3 shows the pressure and temperature curve during operation of the device according to the invention. Due to the centripetal acceleration occurring during the rotation, the pressure p _{r of} the gas in the interior 3 increases towards the outside and reaches its outer diameter r _{a of} the interior 3 greatest value. A similar curve profile results for the temperature T _{r0 of} the gas in the interior 3, which is shown in FIG. 3 with a solid line. The temperature rises continuously from a temperature T _i0 on the inner diameter η to a temperature T _a0 at r _a . If heat is now introduced into the system at the first heat exchanger 4 and withdrawn from the system at the second heat exchanger 5, the temperature profile T _r ι shown with broken lines is obtained, with a temperature J at η and T _a ι at r _a . It is immediately apparent from FIG. 3 that the following relationships apply:

With a sufficiently high speed of the rotor 2 and correspondingly selected boundary conditions, it can always be achieved that

that is, the heat exchanger 4 can be operated at a lower temperature than the heat exchanger 5. When using the device according to the invention for cooling, the heat exchanger 4 can be arranged in a cooling circuit and the heat exchanger 5 essentially dissipate the heat to the environment. Conversely, when used for heating, the heat exchanger 4 can be connected to a heat source at ambient temperature, and the heat exchanger 5 can be used to deliver heat at a correspondingly higher temperature level.

4 shows a rotor 12 of another embodiment variant of the invention. Two inner spaces 3a, 3b are provided side by side in the rotor 12, each of which is provided on the inside with a first heat exchanger 4a, 4b and on the outside with a second heat exchanger 5a, 5b. The rotor 12 has an insulating layer 6 on the outside to avoid heat losses. The heat transfer media for feeding the heat exchangers 4a, 4b; 5a, 5b are preferably fed in or discharged axially, with 7 schematically denoting a first line for supplying a first heat exchanger 4a, and 8 denoting a second line through which the heat exchanger 5a opposite the first heat exchanger 4a and the other first Heat exchanger 4b is connected and with 9 a line through which the heat from the second heat exchanger 5b is removed from the rotor 12. It is obvious that the lines 7, 8, 9 only indicated here each consist of a supply and discharge line and that corresponding pumps or the like for circulating the heat exchanger media are provided, which are not shown here for reasons of simplification.

4, two interiors 3a, 3b are arranged in a single rotor 12. It is obvious that it is equally possible to provide two separate rotors or two individual rotors, which are manufactured separately but are firmly connected to one another on a common axis la.

The device according to the invention makes it possible to provide a thermodynamically highly effective device which can be used in many different ways.

Claims

PATENT CLAIMS

1. A method for transferring thermal energy, the thermal energy being introduced via a first heat exchanger (4; 4a, 4b) into an interior (3) of a rotating centrifuge, in which interior (3) there is a gaseous energy transfer medium, and the heat being transferred a second heat exchanger (5; 5a, 5b) is removed from the centrifuge, characterized in that the gaseous energy transfer medium is in an equilibrium state inside a rotor (2; 12) of the centrifuge and that the heat flow is directed radially outwards.

2. The method according to claim 1, characterized in that the temperature of the energy transmission medium increases from the inside to the outside and that the temperature difference of the energy transmission medium between the inner region of the rotor (2; 12) and the outer region of the rotor is at least 5 K, preferably at least 50 K. , particularly preferably at least 100 K and further particularly preferably at least 200 K.

3. The method according to any one of claims 1 or 2, characterized in that the heat transport in the rotor (2; 12) takes place primarily by heat conduction and preferably radiation.

4. The method according to any one of claims 1 to 3, characterized in that the rotor (2; 12) is operated at a speed of more than 3,000 min ^"1 , preferably of more than 10,000 min ^{" 1} .

5. The method according to any one of claims 1 to 4, characterized in that the rotor (12) is operated at a substantially constant speed.

6. Device for the transfer of thermal energy with a rotor (12) which has an interior (3) which is filled with a gaseous energy transfer medium, a first heat exchanger (4a, 4b) being provided in the region of the axis of the rotor, and wherein A second heat exchanger (5a, 5b) is provided in the area of the outer circumference of the rotor (12), which two heat exchangers (4a, 4b; 5a, 5b) are in contact with the gaseous energy transmission medium, characterized in that the gaseous energy transmission medium is in the interior (3) of the rotor (12) is in an equilibrium state.

7. The device according to claim 6, characterized in that a plurality of rotors are provided and that a device for energy transfer from the second heat exchanger (5a, 5b) of a first rotor (12) to the first heat exchanger (4a, 4b) of a further rotor is provided ,

8. The device according to claim 7, characterized in that the first rotor (12) and the further rotor are filled with different energy transmission media.

9. Device according to one of claims 7 or 8, characterized in that the rotors are firmly connected.

10. Device according to one of claims 6 to 9, characterized in that at least one rotor is housed in an insulated protective jacket.

11. The device according to one of claims 6 to 10, characterized in that a gas having a high molecular weight or atomic mass, such as mercury vapor, krypton or argon, is present in the rotor (12) as the energy transmission medium.

12. Device according to one of claims 6 to 11, characterized in that means for avoiding convection currents are provided in the rotor (12).

2003 05 12 Ba / Ka