DE2214566A1 - Rotating steam generator - Google Patents

Description

The invention relates to rotating steam generators, in particular to a novel construction of rotating steam generators Steam generators, especially in machines with closed Rankine circle can be used.

Rotating steam generators are known per se; it is known that they have a number of advantages over conventional steam generators to have. For example, the high centrifugal acceleration leads in such a steam generator to form a sharp boundary between liquid and steam during the evaporation processj such Steam generator produces high quality steam with a steady flow of water and steam and the steam generator works regardless of the general gravitational field and its

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Direction. In addition, the high rotational speeds usually used in rotating steam generators make it possible Heat flows that are considerably above the highest evaporation level for the general gravity field

A machine with a closed Rankine cycle with external combustion as the heat source is an excellent, low-pollution replacement for the internal combustion engines commonly used in motor vehicles. A machine with a closed Rankine cycle developed practically for this application must be small and compact and with organic components Drive fluids of high molecular weight are operated, which can be evaporated with little or with avoidance of decomposition of the organic fluid.

It has been found that rotating steam generators with high molecular weight organic drive fluids, at operated at high speed, can be used effectively to control the high heat flux at the boundary between liquid and to achieve steam that is required for the required compact design of the rotary steam generator, such as for example in U.S. Patent 3,590,786.

However, in rotating steam generators with a flat, heat-conducting wall, a cylindrical steam generator is used the short axial length needed to make a practical Rankine machine strong heat transfer on the wall of the steam generator, and the temperature difference between the inside of the wall of the steam generator and the boundary between liquid and steam in the steam generator is so large that you can either turn off the engine with a very considerably reduced thermal Motor efficiency or at the expense of an unacceptable

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would have to operate a high degree of decomposition of the organic drive fluid for the steam generator.

On the other hand, because the maximum degree of decomposition of the organic drive fluid in a practically usable Rankine engine must be very low and therefore the maximum temperature of the steam generator jacket is determined, a high temperature difference between the wall of the steam generator and the liquid / vapor boundary layer a lower one Result in the temperature of the liquid / vapor boundary layer, which, at a fixed temperature of the condenser, leads to a considerable reduction in the thermodynamic effect Efficiency of the overall system would lead.

It has been shown that the difficulties referred to may be overcome or suppressed to a minimum value by a compactly built rotating steam generator is constructed by a relatively small axial length, which is formed by an axial distance opposing side walls and a running around the outer wall _s which a suitable structural configuration has received, for example corrugated or provided with grooves in the circumferential direction of the steam generator in order to present in the axial direction transverse to the circumferential wall a surface that conducts the heat of combustion and is much larger in extent or length than the straight axial distance between the walls delimiting the steam generator on the liquid / steam Boundary layer.

In such a rotating steam generator that is driven at speeds at which an annular body of high molecular weight organic steam generator liquid continuously on the inside of the peripheral wall with a cylindrical liquid / vapor interface with a radius from the axis of rotation that corresponds to the im general gravitational field achievable boiling heat fluxes

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increases, the greater expansion or length of the steam generator peripheral wall causes a considerably reduced heat flow on the wall, which is considerably smaller than the high heat flow on the liquid / vapor boundary layer, so that the temperature difference between the peripheral wall and the liquid ts / vapor boundary layer is considerably reduced while maintaining the high Π ie de heat flow at this liquid / vapor boundary layer, which is required for a compactly built steam generator, where g] ο j oh; 'cij 1 if _: only (-'a very slight decomposition of the organic vapor ei ·; ·· ■ ujerί Jnid :; occurs.

i rl jndunrs according i:> t (? in rotating steamer zougc-r neuartiror 1 '' -.ciif- 1 rü ti cn.-uj · "ben, which is used to evaporate liquid gl ^(> i .1 cn, cj jiSrhJ 3 .. "iß3 i ⁽¹ J) l ^T '.r; PFIR and Kui]] Oi ¹ I"} \\ s ui gKc- it suitable isi, ii i nsbenonder ^"5 Jici doors with CLOSED: onem Känkinc-Kreislaüi ι - j ng «. ':" 1 <- 1 x.crOcn J aim, Dei "rotating'" * Dampfei-zoufcr zeij-1 an insfcs.im-; cylindrical structure v. \\ X in mutual axial; distance nnp , e] 5rach1 "en Seitenw.'find by a / usaiiimonji '^))'. ' ^1] !!} · '? Ujnfangswand v rbund' n 'ίπΊ so that a vapor "') · · <- Uferr r. R>.. \" With Judges, üowi · - (Uf ΙΊϋ :: si gke i tszul (? i ι ung ίίίΐ ^Λ dfiii j:, j »: j ί '? r. <;u; err <3uin, fennir ο inen rotary drive, the Q (ii \ Du) i] i i. ^j rz ('Uj ·) with a vorgt-j' / O ^ oinrii Drelizali] in 'Dre) iui; g ν · ι irritates, mil e, ¹ : ·)) 7u: »<3mrnenhrinj- <Mi (l ^f in ]] '") · .; ri gke it u) .'Ji-pe r aur; this I 3 ü ri ri K · ^f an der Inneneilf i3 «.» r Uiui angsv.and in i 1 ein) ¹ ;; y] JHd) ¹ J Γ (;] ι; ΐι liquidu / Diiinj i-Grenzschi cht in vcrg «? gf?] jo'iiem ladi-ilnin distance from ü <; v ] jri ^j l; aclise to erriclitcn, r, n t. '/ i /?:; ■)'('I) I ₁ Sied« - ^j -v: ärnios1 röme erjrlion, dip die im a]] g «? iji <iii; _v n :, < Liore j eld accessible ub '± rste igen, far «ir oiiK? Vcrbrennujij "arrangement on the circumferential wall of the steam generator: for heating and vaporizing the liquid located in the steam generator, and finally a device for drawing off the steam from the steam generator, whereby the

• AD ORIGINAL

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straight axial distances between the side walls of the steam generator at the liquid / vapor interface and on the peripheral wall are approximately the same and the peripheral wall is shaped in the transverse and circumferential directions of the steam generator so that a circumferential wall with an inside or outside that conducts the heat of combustion is created, which against the liquid or the combustion arrangement is directed, furthermore these surfaces have a total length in the axial direction which is significantly greater than the straight axial distance the side walls of the steam generator, which creates a heat flow on the peripheral wall that is much smaller than the heat flow at the liquid / vapor interface and a much smaller temperature difference between the wall and the liquid / vapor interface has, while the high boiling heat flow at the liquid / Steam boundary layer is maintained anyway.

The various details and features of the construction and the operation of the steam generator are described using the following drawings, which show:

1 shows a cross-section diametrically through a rotating steam generator according to the invention with a fixed combustion chamber, schematically placed in an energy generation system _t with a closed Rankine cycle with turbine and condenser;

Fig. 2 is a cross-section along the line 2-2 in Fig. Ij Figure 3 is a partial view taken on line 3-3 in Figure 2;

FIG. 4 shows an enlarged partial section corresponding to FIG. 3, with a schematic representation of the radial component of the convection flow of the liquid in the

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Evaporator;

5 shows an enlarged section along the line 5-5 in FIG. 1 for the schematic representation of the tangential or spiral components of the convection current the liquid in the steam generator;

6 shows a view corresponding to FIG. 1 of a modified construction according to the invention of a rotating Steam generator;

Figure 7 is a section along line 7-7 in Figure 6;

8, 9, 10 and 11 enlarged partial cross-sections of Deviations according to the structure and construction of the outer circumferential wall of the rotating steam generator

If you first look in particular at FIGS. 1 and 2, it can be seen that an embodiment of a rotating Steam generator according to the invention a generally cylindrical housing 1 with side walls 2 and 3, which are an axial Have a distance from each other, and a circumferential wall 4 running around it of a predetermined cross-sectional shape and dimension, which will be described in detail below. Is coaxial through the housing side walls 2 and 3 firmly connected therewith guided a shaft assembly 5 on which the steam generator housing 1 is rotatably mounted in bearings 6 and 7. The steam generator can be powered by an electric motor M, which drives a gear 8, which in turn sets the gear 9 attached to the shaft 5 in rotation, are driven.

The barely between the circumferential wall H and the side walls

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and 3 of the steam generator delimits a steam space V within the housing "1 of the rotating steam generator. The space V is connected via a number of steam pipes 10 to an axial passage 11 in the position 5 in such a way that the steam formed in the steam generator is the collects in the space V, from the rotating steam generator through the steam pipe 10, the axial passage 33 and a line 12, for example into a turbine IS or another expansion device torsional energy in cite η damping ii ₍ <~: as line u ' Auntri 1 te sys 1 f? in, when the vapors leave the steam (r;: e up er <iin ch the shaft b and the pipes 3 0 raf' -.rf _; lei '.]] iii-ii! \ p over the circumference <>? i wave I distributed in dun Da :; j i>vz> u <- r, -, «ν (V"]>-; 5.in / "iiriob d. ^ Rch öm Hot or II <.ji; e üUip-j'.lic);'·?' :: J:" »-jhJ .'-'.- C ^ Un ₄ -, "t ^ ti find t ♦

Flüs.sigi't ■ - · · '.'ird>' - * · ■! - ■ ':;. r: · :: --U [^ t; -. r: .ge31 in GfMn same hatred ·? trains; i? t ₅ ι: '■ - H ^r -. · ■■ ·.-.- ά. ΐκρίΧ i: · < ^T ·: i · -] ·.-r drawn versionFi-ji. "t? -i1i die 1 lv"; r- it j.- the steam ore ^: uger in Fon from f ^{! ;} l ·:> i _t <-: cn Κ <_ικ '^ γ ·; · .ι1. : > Δ \ cuinn Axieldurnhlaß 11 in <: ■ · '■ VJeIl': b uii '" r-iiw. Number / Julfi tungsrohre Ib in the der j ■' rzr: U; - <* v ^ 'r;dir; to] .- ¹ '. ι ·; -, Frciln e extending from the axial'ί; chia ¹ * i.'t rU'i "ι, iijdidl <3 I ichttinjr to au one point untf; ■ '. ⁵ It - ^ r 'ι i ¹ :; - ·. α in d ^{; 1} r! !. n: pf (.i .curerf] üss f ^T ~ standardize the '' vlei .tunp: ^r '. ι ^rl It- rinc \ ·; ugsui ". ⁵ - ί <-c v.virmoi sn 3iert ode) jus ': -i: .- <? :: "τ li-scnri": - J κι;] i < j r> ati ? Ri α 1 hf? Rgt-Ftf ^: ' J t, because the I " · ^{ '~ Si fkeii :: <i - ι .ir: \ < η i - ■ · η "J ■' jiiiiUr.t nit ^ eir Radi alsbiv * ■ - ··· '"" τ \: ind ' / ■ \ -. 'Βη <Ί rc] · - ^; "ni'-ct'- i ^ r in dc'U'irn dei- Dreh · ..- '! ■ :, no d.'ik- h ^: .i Π1: ί ..'.» Ά ;: , 'y : ■ Er \: ^r n:, unp, der υ ;.' ·: R lower-? "Ru«. ·]; r- ci.i τ) ·: · 'η;"!" μ i '~' · ■ it Ddi .jj inner: "> 5 der hciir '· U M [.''ha]' ■ i, vv ^ 'ijeii and <- · ι- 3ϊΓ.ϊ;: ; ^τ b'.iji I- ;:] en der nüsr: «'ii eintr · leu j:" - nn1: c,

The flowing ■■■ Kondeirai \ ⁷ ird to the / · ^ ".. J through] ah · IM dur ..]? I ^j ine. Line 3 (->" iUR (»inem Kondcns-Ttoj-" i /;: rf-e] eii ei, den: f-.v τ ".ί» '~

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passage via a line 18 to the outlet of the turbine 13
connected is. The supply pipes 15 are just like
the steam pipes 10 are evenly distributed in the steam generator housing because of the balanced rotational movement. The radial steam pipes 10 and supply pipes 15 are shown in FIG
a steam generator of the type described required to the radial flow of the liquid and the steam in the interests of undisturbed and efficient operation of the
To enable steam generator; the reasons for this are in
individually in said U.S. Patent 3,590,786. Instead of the tubes 10 and 15, however, can also
Baffle plates or similar devices are used, which ensure that the liquid located in the steam generator rotates with the steam generator.

The rotating steam generator is powered by a motor M with
a predetermined speed in rotation, which is calculated so that a sufficiently large centrifugal force
arises in order to distribute the selected steam generator liquid evenly along the circumference and in contact with the inside of the circumferential wall M and in this state to
hold, with a liquid ^ / vapor boundary layer denoted by χ (Fig. 1), which is very stable and in the
is substantially cylindrical and concentric to the axis of rotation of the steam generator. The liquid / vapor boundary layer χ is essentially at a predetermined radial distance from the axis of rotation of the steam generator, in order to achieve a high boiling heat which exceeds that which can be achieved under the general effect of gravity, and uir: the required steam generator (steam) pressure
to generate r >> r the radial length of the liquid column
is assigned in the supply pipes 15.

Around a rotating steam generator of sufficiently small dimensions for you to be able to produce practical use in an engine with a closed Rankine cycle,

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must be the diameter of the outer peripheral wall 4 of the Steam generator and the axial distance between the end walls 2 and 3 are kept as small as possible and there must be a liquid / vapor boundary layer at the same time as the rotational speed χ are made of sufficient axial length and with a sufficiently large radius, to generate the above-mentioned high boiling heat flux and the required steam generator (steam) pressure.

As mentioned, it has not yet had a powerful rotating steam generator for the use of organic drive fluids given high molecular weight in a closed Rankine cycle engine because of the usual constructions of rotating steam generator with the usual flat peripheral wall, their axial extension is equal to the axial length of the liquid / vapor layer, the heat flux on the peripheral wall is high and the temperature difference between this wall and the liquid / vapor layer is so large, "that the engine can only use one very low thermal efficiency or at the expense of very rapid decomposition of what is to be evaporated organic drive fluids can be operated.

In the context of the invention it has been shown that by a certain shape or a certain structure of the Peripheral wall 4 of the steam generator, so that in the axial In the direction transverse to the wall 4, a surface which mediates the heat conduction between combustion and liquid is provided whose total length is much greater than the linear axial distance between the side walls 2 and in the area of the liquid / vapor boundary layer, a significant caused lower heat flow on the steam generator wall 4 is, resulting in a significant decrease in the temperature difference between the steam generator wall

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and the liquid / vapor interface. Surprisingly this temperature difference is significantly lower than merely due to the increase in Area of the corrugated circumferential wall of the steam generator 4 compared to the area of a corresponding steam generator wall usual flat shape can be expected. Due to this design and the associated consequences, the required high heat flux at the liquid / vapor interface can be maintained and the steam generator with maximum overall engine efficiency with very little or operated at all without decomposition of the organic vapor-generating fluid.

The required increase or greater axial length the area of the circumferential wall of the steam generator that conducts the heat of combustion results from the circumferential wall 4 so that in its circumferential line a number of parallel grooves 20 (Fig. 1) develop. The wall 4 is made of any heat-conducting material, such as steel, copper, aluminum and the like and the number of grooves 20 and their shape and dimensions are selected and calculated so that a total length the heat-conducting peripheral wall surface in the axial Longitudinal direction compared to the straight axial length of the liquid / dampening boundary layer is created, which is sufficient that the steam generator with minimal decomposition of the organic drive fluid with a maximum overall thermal efficiency of the motor operating with a closed Rankine cycle.

In particular, it has been found that the total axial length of the heat according to the invention in the liquid conductive peripheral wall surface at least one and a half should be times as big as the AxialaNfitanc! .-. v / i-

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see the side walls 2 and 3 of the steam generator in the Area of the liquid / vapor interface (i.e. the straight axial length of the boundary layer χ in Fig. 1); preferably and for the best results, should said length approximately three to five times the straight axial distance between the end walls 2 and 3 of the steam generator at the boundary layer χ or the axial length of this boundary layer. This information apply to "smooth" inner surfaces of wall H and these Results can be achieved in addition to the other possibilities that result from increasing the surface roughness result, i.e. by the "boiling stone effect", which is produced in a manner known per se by sandblasting the inner wall surface of the steam generator or by gluing metal powder or porous materials to the wall.

The liquid ring in the steam generator can be brought to the boiling temperature required for evaporation, for example by burning a suitable fuel-air mixture in a fixed combustion chamber 21 which surrounds the housing of the rotating steam generator 1. The required for the combustion of fuel is injected through a nozzle 22 in the required amount and under proper pressure into the combustion chamber 21, and for mixing with the fuel eriorderliche air passes through a ⁷ eIHE i'finunpcn 23 in the Umfangswanc. 2U in the front! ι ennuiij t ^; ? a'im. Line Haul. ·· » 7L · forms an air chamber 26 into which air is introduced through a duct 27 under suitable pressure and volume conditions, so that effective combustion of the > Brcnr .: ' of fsr, u «l'rhitzen (V ¹ V liquid ⁴ " in d <-rr J ^ jmpferzcuf-erfehause to the required temi '· "iii i; r takes place. gases enter 'lurjh a ΑΙ., ςβε] ·. tv.; =. \ « ^; f into the open, and (i) · fixed] ·? transverse wall? 9 K'i.t ι, νη'Μ r'n 30 which are shown in Fig. 1-

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len 20 protrude into the steam generator peripheral wall 4 is arranged between the fuel nozzle 22 and the exhaust passage 28 to allow the circulation of the combustion gases steer.

In one construction, a rotating steam generator constructed in accordance with the invention had a circumferential steam generator wall 4 made of metal of 0.787 mm (0.031 ") thickness and contained circumferential grooves 20. The inner or The outer diameter of the groove surface was 15.24 cm (6 ") or 17.62 cm (6 15/16"), and the spacing was more corresponding Profile points of the grooves in the axial direction was 8.51 mm (0.335 "), the outer and inner radius of curvature the groove tips were 0.787 mm (0.031 ") and 1.574 mm (0.062") with a straight axial spacing of 3.4 cm (1.34 ") at the liquid / vapor interface between sidewalls 2 and 3 of the steam generator.

In the specified steam generator, the circumferential wall 4 has the grooves 20 in the axial steam generator direction Total length of the surface of the peripheral wall 4, which is 3.16 times the straight axial distance between the side walls of the steam generator,

In operation, the rotating steam generator described has a very low heat flux at the peripheral wall 4 and develops much smaller temperature differences between the viand 4 and the liquid / steam boundary layer with a high boiling heat flux at this boundary layer, compared to τ. it ninein rotating steam generator of the same type with a flat or axially flat peripheral wall surface. If, for example, el, Qk- ^Bi ( ^{ti: i} ifluoromethyl) benzyl alcohol] for the operation of the steam generator at 4,500 rpm and a

2
Steam generator pressure of 3.87 kg / cm abs. (55 psia) spoiled. "-!

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and heated so that a heat flow of 12 820 cal / hour on the steam generator wall 4. cm ² (47 200 Btu / hr ft ² ) is formed, there is a temperature difference of 32.2 ° C (58 ° F) between the wall 4 and the liquid / vapor boundary layer. A similar steam generator with a flat peripheral wall and the same straight axial distance between the side walls of the steam generator would be 1/3.16 of the steam generator area and therefore require a heat flow of 40 cal / hr cm ² (149,000 Btu / hr ft ² ) to achieve the Fluid to be able to supply the same amount of heat.

In comparison, in a similar steam generator with a flat peripheral wall, under the same conditions, but with a heat flow of 40,400 cal / hr cm (149,000

Btu / hr ft) working on the boiler wall, the temperature difference between the peripheral wall and the liquid / vapor interface is 46.1 ° C (83 ° F). If, on the other hand, the same steam generator with a flat circumferential wall was heated less, so that only a heat flow of 12 820 cal / hour cm ² (47 200.-

Btu / hr ft), there was still a temperature difference of 41.7 ° C (75 ° F) between the peripheral wall and the liquid / vapor interface.

In the following table I the results are given, which result from the above-described and from further experiments with structured steam generator walls in Compared to steam generators with a flat peripheral wall:

Table I.

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Table I.
The steam generator was operated at 4500 rpm.

Steam generator wall construction

Steam generator pressure psia (kg / cm ² abs.) Heat flow

Btu / hour fir (cal / hour cm) Mean Same length Executed temperature surface wall steam generator difference

wall ⁰ F ( ⁰ C)

Steam generator liquid: cL, d — Bi (trifluoromethyl) benzyl alcohol

H in oo

NJ O CD CO

Wall with grooves flat wall flat wall

55 (3.87) 55 (3.87)

55 (3.87)

Steam generator fluid: benzene Wall with grooves 14.7 (1.03)

flat wall flat viand wall with grooves flat wall flat wall

14.7 (1.03) 14.7 (1.03) 14.7 (1.03) 14.7 (1.03) 14.7 (1.03) 149.000 (40,400)

149,000 (40,400)

47,200 (12,820)

368,000 (-9 9,200)

368,000 (99,200

116,500 (31,600)

272,000 (73,750)

272,000 (73,750)

86,100 (23,340)

47,200 (12,820)

149,000 (40,400)

47,200 (12,820)

116,500 (31,600)

358,000 (99,200

116,500. (31,600)

86,000 (23,340)

272,000 (73,750)

8 6,100 (23,340)

58 (32.2)

83 (46.1)

7 5 (41.7)

66, (36.7)

111 (61.7)

80 (44.4)

66 (36.7)

100 (55.6)

77 (42.8)

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The unexpected advantages brought about by the inventive Training of the steam generator achieved seem to be of a novel scrubber effect between the particles of the steam generator liquid and the in the circumferential wall extending annular surfaces, which are formed by the grooves in the circumferential wall U of the steam generator. As in FIGS. 4 and 5 schematically shown, the particles of the steam generating liquid are moving within the rotating steam generator on trajectories that contain both radial and tangential sections, with different accelerations and speeds, as shown in FIGS. U and 5 by the arrows is indicated "

For example, it is assumed that a liquid particle extending from the peripheral wall U inwardly into Moves towards the liquid / vapor interface, is accelerated and in the direction of the steam generator rotation runs at a speed that is greater than that of the steam generator (arrow A in Fig. 5), while a liquid particle, that differs from the liquid / vapor interface moved away towards the peripheral wall t, from the greater velocity of the liquid at the liquid / vapor interface practically on the Speed of the peripheral wall at its outer radius is slowed down (arrow B in Fig. 5).

As a result of this inward and outward orbital movement of the liquid particles with the associated changes the path speed due to accelerations and decelerations in the liquid body of the steam generator, ' the individual liquid particles seem to rotate in a * "at high speed« "· <·: i> Steam generator a number of circulations - within the umlauji'-nden liquid -

-lh - '^.' ■■ '■ ..

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, 2 21

/ b

before they reach the liquid / vapor interface arrive and be vaporized at the desired steam generator (steam) pressure. Under these circumstances the liquid particles become in scrubber interaction with the inside of the peripheral wall for a period of time 4 held, with maximum heat transfer from the wall 4 to the steam generator liquid.

Further advantages result in the context of the invention from the reduced thickness of the grooved Steam generator wall. The steam generator wall equipped with grooves is set up for the same load much thinner than the flat wall of the steam generator of the same axial extent that at the liquid / steam boundary layer causes the same heat flow. The thinner metal wall of the fluted steam generator requires when operating with a fraction of that occurring in a steam generator with a flat wall on the peripheral wall Heat flow a considerably smaller temperature gradient in the metal wall in order to achieve the required heat flow to guide through the wall. The difference in temperature gradient between a fluted and a flat one Wall in a steam generator is even larger if the steam generator has flat wall projections on the Has outside of the wall in order to increase the heat transfer from the combustion gases. The degradation of the temperature gradient at the steam generator wall in a steam generator with a corrugated wall sets the middle ' ler wall temperature and thereby allows the use of cheaper alloys. That means that the normally required expensive steam generators operating in a closed Rankine cycle Alloys do not need to be used. In addition, the lower temperature increases the outside of the

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corrugated steam generator wall significantly because of the larger heat transfer from the hot combustion gases Temperature difference between the hot gases and the steam generator wall; .the burner efficiency is thereby improved. Another benefit of the specified steam generator's thinner metal wall is that it is faster Response to increased heat input.

Figures 6 and 7 show a modified construction a rotating steam generator according to the invention again. The rotating steam generator then represents a wheel-like structure, consisting of. a ring housing la with side walls that are axially spaced from one another 2a and 3a and a contiguous outer circumferential wall Ha led around with also led around coherent and mutually parallel grooves 20a of the construction and arrangement described above. The ring housing la is carried concentrically by a shaft 5a and a number of steam tubes 10a. The wave 5a is rotatably mounted in bearings 6a and 7a and the steam generator can be powered by an electric motor M ', which is a Driving gear 8a, which meshes with a gear 9a mounted on the shaft 5a, at the required speed be set in rotation.

The space delimited by the circumferential wall la and the side walls 2a and 3a of the housing la represents a steam chamber V ¹ which is connected via the steam tubes 10a to an axial passage lla in the shaft 5a, so that the steam formed in the steam generator is collects in the space V, is passed inward through the steam tubes 10a and the axial passage lla into an expansion space already mentioned above.

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The liquid is supplied to the steam generator, for example as a liquid condensate, through an axial passage IUa in the shaft 5a is supplied with a number of supply pipes 15a which radially outward within the steam pipes 10a to a point below the level of the steam generator liquid are led. The steam pipes 10a and the supply pipes 15a have with respect to the shaft 5a and of the steam generator housing la the same arc spacing so that no unbalance phenomena occur on the steam generator.

The rotating steam generator is set ^{in rotation by the motor M 1} at a predetermined speed in such a way that the selected steam generator liquid is evenly distributed over the circumference of the inner side of the circumferential wall 4a of the steam generator and a cylindrical liquid / steam, denoted ^{by x 1 in FIG.} Boundary layer occurs. If the steam generator is operated in the manner explained in connection with FIGS the liquid / vapor boundary layer x ¹ than is the case with a corresponding rotating steam generator with a flat peripheral wall.

The design and structure of the circumferential wall of the steam generator are not based on the special designs with grooves20 and 20a in the walls 4 and 4a according to FIGS. 1 and 6 limited. Various other designs can be selected, as shown for example in FIGS. 8, 9, 10 and 11, the embodiments according to FIGS. 8 and 10 as long as preference over the configurations according to FIGS. 9 and 11 is to be given, as the training of the

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circumferential wall used the increased overall axial length the surface of the wall Ha that emits the heat to the liquid ensures the required low Heat flow on the peripheral wall and the low temperature difference between the wall and the liquid / vapor interface to deliver the necessary for the operation of the steam generator at the desired high heat flow to the Liquid / vapor boundary layer with the lowest possible Decomposition of the steam generator fluid are required.

From the above description it can be seen that the invention provides a rotating steam generator which is relatively small due to the compact design and has high strength. Such a steam generator is particularly suitable for the use of high molecular weight organic drive fluids and provides one high heat flux at the liquid / vapor interface with minimal degradation of the drive fluid and significantly lower heat flow on the circumferential wall of the steam generator. The resulting temperature difference between the circumferential wall of the steam generator and the liquid / Steam boundary layer is sufficiently low to be rotating Steam generator in a closed Rankine cycle engine with aiaximal overall thermal efficiency to let the engine work with rapid response to increased heat input.

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Claims (2)

cR-7158 g 2 21 A 5 6 6 2 k. MAR. 1972 Patent claim: Rotating steam generator, characterized by a generally cylindrical structure with mutually spaced side walls (2, 3), which through ane contiguous peripheral wall (4) are connected, so that a steam generator space (V) is created, a liquid feed line (15) for the steam generator space (V), a rotary drive (M, 8, 9) that connects the steam generator set in rotation at a predetermined speed to form a coherent body of liquid from this liquid on the inside of the peripheral wall (4) with a cylindrical liquid / vapor boundary layer (x) in a predetermined to erect radial distance from the axis of rotation, so that high boiling heat flows result, which in the exceed the general gravity field achievable, a combustion arrangement on the peripheral wall (4) of the Steam generator for heating and vaporizing the liquid in the steam generator, and by means for drawing off the steam from the steam generator, the straight axial distances of the Side walls (2, 3) of the steam generator at the liquid / vapor boundary layer (x) and on the peripheral wall (U) approximately are the same and the peripheral wall in the transverse and circumferential directions of the steam generator is shaped so that one the The circumferential wall that conducts combustion heat is created with an inner or outer side that acts against the liquid or the - 20 209841/0126 CR-7158 j. combustion arrangement is directed, furthermore this Areas have a total length in the axial direction that is significantly greater than the straight axial distance of the Side walls (2, 3) of the steam generator, whereby a heat flow is created on the peripheral wall (4), which is essential is smaller than the heat flow at the liquid-vapor layer (x) and a much smaller temperature difference between the wall (4) and the liquid / vapor boundary layer (x), while the high Boiling heat flow at the liquid / vapor interface (x) is maintained anyway. - 21 - 209841/0126 Blank page