DE1503490A1 - Aerodynamic pressure wave machine - Google Patents

Description

6/66 DrW / schu

Brown Public Company. Boveri A Cie., Baden (Switzerland) Aerodynamic pressure cylinder machine

The invention relates to a method for operating a aerodynamic pressure wave machine, which comprises at least one cellular wheel and frontal distributor with inlet and outlet openings for hot and cold gas approximately the same pressure of the compressed cold and the hot oasis to be expanded in the high pressure zone and significantly lower pressure of the cold oasis to be compressed compared to the expanded hot oasis in the low-pressure zone, and a pressure wave machine to carry out the process.

In aerodynamic pressure wave machines a hot Oas relaxes from a higher to a lower pressure and the fixpanslonsenergle obtained is used to create a compressing cold oas from a lower to a higher pressure eu * With these machines, two main groups differentiated »

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a) The pressure exchanger (e.g. after the DP 724 998), in which

Pp C ~ Vp. and p. s? p ,, is. DiE means that the cold gas from p to p _? is compressed and the hot gas from p _? on p-, expands. (The indices ν and η therefore stand for before and nacr., 1 and 2 for the lower and higher pressure level, respectively.) As an energy balance shows, a greater amount of energy is available due to the expansion taking place at high temperature than at the same mass flow rate is required for the compression ψ turi (i of the cold gas. To compensate for this, either the mass of cold gas processed in the pressure exchanger must be greater than that of the hot gas, or the excess part of the hot gas must be expanded in another machine , whereby a temperature permissible for this machine is reached by mixing with cold gas, but this means a thermodynamic devaluation.

b) The pressure transducer or pressure transformer (e.g. according to DP 1 000 132), in which the restrictive conditions applicable to the pressure exchanger with regard to pressure equality do not occur. According to the current state of the art, a large pressure difference (p, - p,) can only be achieved if (p _o ■ - Po) is large because otherwise, as can be seen from the pressure-speed diagram, the wave cycle will not close would. Should a greater pressure ratio be required for the cold gas

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be enough, so Ppn ^ lv ^ ^Ρ · 2 ^^ 1η ^his "can also at the same mass flow rate cold and hot gas, the energy balance between compression and Expansionsenerj;. le compensate.

For some thermal processes, a pressure wave machine would be desirable, in which Ppn ^ Ppv ^unci * Ί ^^ l ^{is /} ^ ^ie expansion takes place in as high a temperature range as possible and the mass flow rate of cold and hot gas is approximately the same. If, for example, in a gas turbine system the pressure wave machine is to be connected downstream of the compressor or upstream of the gas turbine on the flow side, then Pp _n ^ Pp / ^ ^a ^ ^er pressure loss in the combustion chamber would be relatively small. The whole mass of the hot combustion gas in the pressure wave machine could expand and the air would be sucked in at a pressure level that would be significantly lower than that of the gas outlet. That would mean that the compressor would be relieved, i.e. less power consumption and therefore useful power and efficiency would increase.

A solution to this problem was not previously known. The invention is based on the object of an aerodynamic To train pressure wave machine so that it is under the

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mentioned conditions can work. According to the invention, this object is achieved in that at least one gas flow divided in the high pressure zone and the main flow is used to generate energy, while the remaining partial flow supports the flushing of the cells in the low pressure zone. A pressure wave machine which is used to carry out this Process is suitable, has an additional inlet opening for the partial flow.

In the drawing are two embodiments of the invention which are described in more detail below. Show it

Fig. 1 and 3 schematic representations of the developments each a cylinder section at half the height of the cells through the cellular wheel and through the frontal ones Distributor with the inlet and outlet openings;

2 and 4 the associated wave cycles in the pressure-speed diagram.

In FIGS. 1 and 2, the hot gas flows to the high-pressure inlet openings 2v of the pressure wave machine and exits again from the low-pressure outlet openings In. The cold gas flows to the low-pressure inlet openings Iv and emerges again from the high-pressure outlet openings 2n. The dashed line illustrates the dividing front between

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1503A90

see hot and cold gas. The direction of movement of the Cells is indicated by an arrow.

At the beginning of the cycle, the oil cell in FeIc O is filled with cold gas. In a known manner, the main stream of the neisser flows through the high pressure inlet opening 2v; Gas enters the cell from the pressure pp in the fields 1, 3, compresses the cold gas to the pressure p, and pushes it out in the fields 2, 4 through the high-pressure outlet opening 2n. The pressures p «and p_sine only v <t-nit; different from each other. The outlet opening 2n is closed in front of the inlet opening 2v, so that the high pressure in field 6 remains after the cell has been rinsed in the high-pressure zone. In field "( a part of the expanded hot gas therefore enters the low-pressure outlet ^{opening In 1} at high speed and sucks in cold gas from the low-pressure inlet opening Iv ¹ in field 8. But because the pressure in field 8 is much lower than in Field 7, reflections of the waves would quickly stop the flushing in the low pressure zone and reverse it. To prevent this, the cell is closed again in good time on both sides and a medium pressure remains in field 9.

According to Figures 1 and 2 now flows into field 10 a part

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flow of the hot gas from _{the pressure kp 2v} into the high-pressure inlet opening 2v 'and charges the cell in the area 11 to a pressure which is higher than that in the area 9. This means that there is enough energy for a second flush in the low-pressure zone. In fields 12, 14 the remaining hot gas flows out into the low-pressure outlet opening In and in field 1} the cell is filled with cold fresh gas through the low-pressure inlet opening Iv. If necessary, a further high-pressure inlet port 2v ^f 'and a third purge vorgeeehen be in the low pressure zone, otherwise the cycle in the box 15 ^a O begins again.

The cycle according to Figures 2 and 4 is identical to that of Figures 1 and 2 up to the state in field 9 Gas which is under pressure p ₂ , branched off a partial flow and fed through the high-pressure inlet opening 2η ¹ in field 10 of the cell, while the main flow is fed to the intended use. This means that the energy required for a second flushing of the cell in the low-pressure zone is available, so that the remaining hot oases in field 12 flow out through the low-pressure outlet opening In. In the fields 13, 14 a thorough flushing and the filling of the cell with cold fresh gas takes place.

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This process is probably inferior to the process according to FIGS. 1 and 2 in terms of overall efficiency. By using of the colder high-pressure gas to support the purging However, the hot gas is displaced from the cell faster and the cell is better flushed through and cooled.

Here, too, if necessary, a further high-pressure inlet opening 2η ¹ 'and a third flush can be provided in the low-pressure zone. It is also possible to divert a partial flow from both the hot and cold high-pressure gas and use it to support the flushing in the low-pressure zone.

According to FIGS. 1 and j5, the separating front reaches in field 6 the right end of the cell, which can be an advantage, as the buffer zone e.g. reduces the heat transfer. The machine can also be designed so that the separating front reaches the other end.

In Figures 1, 1 and JJ there is a reverse flow pressure wave machine shown, i.e. the gas exits on the same side of the cellular wheel on which it entered. Of course, the concept of the invention can also be applied to machines with a flow through which the gas is exposed enters on one side and exits on the other. It is also irrelevant whether the machine is stationary frontal distributing and rotating cellular wheel or with

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rotating distributors and fixed star feeder. Likewise, the inlet and outlet canals within of the machine or several separate lines can be arranged.

The pressure wave machine according to the invention can with thermal Processes are used in which they were previously not applicable or only applicable with disadvantageous restrictions was. The good flushing in the low pressure zone enables a higher degree of purity of the cold to be compressed Gases than he was previously available. If the pressure wave machine is connected upstream of an oasturbine, its speed can can usually be chosen optimally. Should coordination difficulties arise with certain partial load conditions, so gas pockets can be used in a known manner. Further possible uses of the invention

These pressure wave machines are used in the chemical industry, in process engineering and for charging diesel engines available.

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Claims (1)

Patent claims I. Procedure for operating an aerodynamic pressure wave machine, the at least one cellular wheel and end-face distributor with inlet and outlet openings for hot and includes cold oas, with approximately the same pressure as the condensed one cold and the hot gas to be expanded in the high pressure zone and much lower pressure of the to compressing cold gas compared to the expanded hot gas in the low pressure zone, characterized in that that at least one gas flow is divided in the high pressure zone and the main flow is used to generate energy, during the the remaining partial flow supports the rinsing of the cells in the low-pressure zone. II. Aerodynamic pressure wave machine for performing the Λ
Method according to claim I, characterized by at least one additional inlet opening (2v *, 2n ') for the partial flow. Public limited company BROWN, BOVERI ft CIE. 009815/0549 JO Blank page