Power translation device

An apparatus for translating motive energy includes a rotor structure, having mutually spaced rotor members, adapted to react with fluids within the housing. In one embodiment, the rotor structure is rotationally driven by an external power plant for pumping fluids through a tangentially oriented outlet duct. In a second embodiment, the apparatus is driven by fluid under pressure which is conducted toward the rotor structure through an inlet aligned with peripheral portions of the rotor members, for rotationally driving the rotor structure. A variable geometry inlet control system is provided for controlling fluid flow in response to varying flow conditions and for directioning fluid flow to a portion of the rotor structure. The apparatus incorporates a structural configuration which permits its construction of carbonized composite materials, for operation at elevated temperatures.

TECHNICAL FIELD 
This invention relates to power translation devices and, more particularly, 
to turbine and pumping apparatus operable at elevated temperatures. 
BACKGROUND ART 
Designers of turbines such as those employed in vehicular and aircraft 
power plants have observed that high operating efficiencies are generally 
associated with high operating temperatures, because of the greater energy 
levels of high temperature gases. Internal temperatures of modern turbine 
engines may typically exceed 1500.degree. F., for example. Moreover, the 
increased efficiencies potentially obtainable at even higher temperatures 
have not been realized, largely because of limitations in the properties 
of materials in current use. Because of the deleterious effects of high 
temperature gases upon structural components, the use of a variety of 
metallic and non-metallic materials have been considered, including the 
ceramics, tungsten alloys, and more recently, carbonized composites. 
Whereas ceramic materials are known to be capable of sustaining very high 
temperatures in certain applications, they tend to be deficient in 
toughness and resistance to fracture under high stress and vibrational 
loads. In addition, they are subject to failures, particularly during 
extended use, when subjected to rapid temperature variances, and to 
localized thermal shock entailing differing temperatures within an 
integral component. 
Carbonized composite materials are currently being employed in certain 
aerospace structures which sustain substantial mechanical and thermal 
stress. Typical applications include the leading edge portions of space 
craft which are exposed to high temperatures and stresses during reentry. 
Such composite materials typically include a fibrous component, e.g., 
fibrous boron or graphite, in a matrix of a thermosetting polymer 
material, such as a phenolic. Processes for their manufacture typically 
entail the formation of an uncured workpiece substantially of the 
configuration desired for the structure, normally with a large proportion 
of the fibrous components substantially aligned with the axes subject to 
greatest stress. The workpiece is cured under a prescribed 
time/temperature/pressure cycle and then pyrolized under higher 
temperatures to form a high strength carbonized structure, having both 
fibrous and matrix components in the carbonized state. The cured 
workpiece, or substrate, may then be coated with an oxidation resistance 
coating typically containing silicon carbide and silicon metal. Such 
coated carbon-carbon materials have been demonstrated to maintain 
structural integrity when exposed to temperatures in excess of 
2000.degree. F. and have substantially greater structural strength and 
toughness than most ceramic structures. Additionally, they may be 
selectively reinforced to enhance resistance to stress loads along 
particular axes, as suggested above, and at particular regions, by 
appropriate orientation and configuration of the fibrous reinforcing 
material prior to curing. 
The commercial manufacture of such composite structures is difficult, 
however, if parts of complex structural configuration are entailed. For 
example, whereas multi-bladed turbine rotors of complex configuration may 
be formed readily of various metal alloys by techniques well known in the 
art, the manufacture of a carbonized composite rotor having a plurality of 
blades or buckets and having the capability of sustaining extremely high 
circumferential and vibrational loads entails substantial technical 
difficulty. The rotational elements of gas-driven turbine aircraft engines 
may be driven at rotational velocities exceeding 50,000 revolutions per 
minute. If formed as a composite structure, lay-up of the fibrous 
components of such a multi-bladed turbine rotor is difficult because of 
the structural discontinuities alongside and at the periphery of the 
rotor, and because of the angular projection of the blades from the plane 
of the rotor disc. Under the substantial structural loads entailed at high 
rotational velocities, together with the vibrational cyclical thermal 
stresses, such multi-surfaces, bladed components are susceptible to 
distortion and structural failure, and the blades may tend to be broken 
away from the central disc. In contrast, a rotatable composite disc having 
an integral, continuous peripheral region (one not divided into multiple 
blades or buckets) may be more effectively reinforced and manufactured for 
sustaining the circumferential loads entailed even at very high 
temperatures and rotational velocities. 
A turbine-pump apparatus developed by Nikola Tesla, disclosed in U.S. Pat. 
Nos. 1,061,206 and 1,061,142, incorporates a rotor structure having a 
plurality of non-bladed rotor discs mounted coaxially on a rotatable shaft 
in mutually spaced, parallel alignment. As will be understood more fully 
from the description hereinbelow of the present system, such "Tesla 
turbines" and pumps make use of forces derived from surface reactive 
forces, i.e., forces related to the reaction of a fluid against asperities 
on the surfaces of the discs, and from surface tension forces related to 
viscosity of the fluid, i.e., from adhesion of the fluid to the disc 
surfaces. Thus, fluid injected tangentially into a Tesla turbine apparatus 
between the discs reacts with the disc surfaces, because of surface 
tension and reactive impelling forces, to drive the discs in the direction 
of flow. The teachings of the Tesla U.S. Pat. Nos. 1,060,206 and 1,061,142 
are hereby incorporated by reference. 
As disclosed in the U.S. Pat. No. 1,061,142 patent, such rotatable, 
multiple disc structures are also operable as fluid pumps. When the discs 
are rotated by means of an external motor, fluid is ejected by the discs 
through a fluid outlet aligned tangentially with the discs. Inlets are 
provided in the housing communicating through the central regions of the 
discs, as disclosed in the U.S. Pat. No. 1,061,142 patent. Thus, while the 
discussion herein will be directed largely to an improved, gas driven 
turbine, it will be apparent from the description and from the teachings 
of the U.S. Pat. No. 1,061,142 patent that such power translation 
apparatus may also be operated as fluid pumping devices. 
Although such Tesla power translation apparatus have in fact been employed 
in certain industrial applications, they are not commonly used in modern 
gas driven turbines. As will be understood from the description 
hereinbelow of the operation of the present system, propulsive gasses of 
substantial temperatures and mass flow rates are preferably employed to 
drive such turbine apparatus. Because of the high flow energy and 
operating temperatures, conventional, metal components are susceptible to 
rapid deformation and deterioration when used in the preferred embodiment 
of the invention. Furthermore, conventional Tesla turbine configurations 
(as exemplified in U.S. Pat. No. 1,051,206) are undesirably inefficient 
with respect to energy transfer and aerodynamic flow. In such 
configurations, as the inflowing gaseous mixture enters the generally 
cylindrical chamber in which the multiple discs are rotatably mounted, 
flowing from an inlet duct along a tangential axis toward the discs, the 
flow is permitted to expand within an enlarged inlet throat, and 
subsequently within an annular, circumferential manifold cavity or ramp as 
it merges with the interior disc chamber and gradually merges with and 
flows between the discs along a spiral path. Because the gases under high 
pressure passing through such an inlet throat or chamber are permitted to 
expand, they lose potential energy while increasing in turbulence, and 
they subsequently further increase in turbulence as they enter the spaces 
between the discs. Energy is therefore dissipated by the expansion of the 
gases within the throat and manifold chambers prior to reaction of the 
gases with the discs. As the turbulent gases strike the peripheral edges 
of the discs they are divided and enter the multiple annular spaces 
defined intermediate the mutually adjacent discs. Further flow 
inefficiencies result as the expanding gases react turbulently with the 
peripheral edges of the discs and enter the intermediate spaces. 
Conventional Tesla turbine apparatus are further undesirably inefficient 
when the velocity of the propulsive gaseous flow is required to be varied 
from a narrow, optimal range. That is, they suffer from an undesirable, 
substantial decrease in efficiency when the flow velocity of the 
propulsive gases falls below a given optimal range, related to the 
diameter and spacing of the discs and the respective areas of the inlet 
and outlet openings. 
Thus, inefficiencies result in conventional Tesla turbines from the loss of 
energy experienced when the inflowing gases are permitted to expand in an 
inlet throat upstream of the disc chamber, when the turbulently expanding 
gases strike the disc edges, and because of the inefficiencies entailed 
during operational regimes other than a full-power mode, in which the 
gaseous flow rate is "tuned" to the particular rotor and housing. The 
Tesla turbine and pump apparatus has not been practicalle for use in 
modern gas-driven turbine engines or high temperature pumps. 
DISCLOSURE OF THE INVENTION 
It is, accordingly, a major object of the present invention to provide new 
and improved turbine and pumping apparatus. 
Another object is to provide such an apparatus having a plurality of 
planer, disc shaped rotors which are integrally constructed and free of 
peripheral discontinuities, having no turbine blades or buckets. 
A still further object is to provide such a turbine apparatus which is of 
high efficiency over a wide range of power levels. 
A further object is to provide a gas driven turbine, having a plurality of 
disc-shaped rotors, which is reliably operable at elevated temperatures in 
excess of 1800.degree.-2,500.degree. F. 
A still further object is to provide such a gas-driven turbine having no 
expanded manifold inlet chamber, whereby expansion of inlet gases occurs 
within the multiple parallel spaces intermediate the discs rather than in 
an inlet throat or chamber upstream of the discs. 
Yet another object is to provide such a turbine in which the inlet gases 
are initially divided within multiple inlet channels in register with 
respective annular cavities between the multiple discs, whereby flow 
turbulence which otherwise results as the gaseous flow passes between the 
discs is substantially reduced. 
A still further object is to provide such a turbine apparatus having inlet 
means for maintaining the inlet flow at a substantially constant flow 
velocity despite changes in total mass flow rate, for enhancing operating 
efficiencies of the turbine as the mass flow rate is varied during 
differing operational regimes. 
Other objects and advantages will become apparent from the specification 
and drawings and from the accompanying claims.

DETAILED DESCRIPTION 
Referring initially to FIGS. 1 and 2, a preferred embodiment of the turbine 
apparatus 10 includes a generally cylindrical housing 11 mounted upon a 
base structure 12, having an inlet duct 13 extending tangentially from the 
housing and communicating with its interior chamber 19. With additional 
reference to FIGS. 2 and 3, first and second outlet ducts, 14, 15 
communicate with the interior of the housing through outlet openings 16, 
seen more clearly in FIG. 7, in the respective housing end walls 17, 18. 
Preferably, the housing 11 and associated inlet and outlet passageways are 
formed of carbonized composite panels. 
With reference to FIGS. 2 and 7, a rotor structure 20 is coaxially and 
rotatively mounted within cylindrical chamber 19, defined within the 
housing 11. The rotor structure 20 incorporates a plurality of mutually 
spaced discs 21 non-rotatably and coaxially mounted upon a common shaft 
22, which extends through corresponding circular openings formed centrally 
through the respective sidewalls 17, 18 of the housing 11. The end 
portions of the shaft 22 extend beyond the respective housing end walls 
17, 18 and are rotatively journaled within first and second thrust bearing 
structures 25, 26, which are mounted upon pedestal structures 27, 28 
affixed to or formed integrally with the base structure 12 at respective 
locations spaced laterally from and on opposite sides of the housing 11, 
as shown most clearly in FIG. 3. The bearings 25, 26 are preferably spaced 
beyond the housing end walls 17, 18 to minimize deleterious effects which 
otherwise result from heat transfer from the housing 11 to the bearings 
25, 26 during operation, from high temperature gaseous flow within the 
housing. 
The central region of the shaft 22, i.e., the portion disposed within the 
housing chamber 19, is integrally formed with raised, linearly extending 
ridges or keyways 30 (FIG. 5) which seat within corresponding grooves 
formed in the circular openings extending centrally through the respective 
annular discs 21, whereby the discs are non-rotatably mounted on the 
shaft. Multiple spacing rings 32, as seen most clearly in FIGS. 2 and 7, 
are similarly mounted on the shaft 22 between the mutually adjacent discs 
21, for maintaining equal spacing between the discs. 
As seen most clearly in FIG. 7, the discs 21 are preferably formed as 
planar, circular plates of carbonized composite material, and they are 
equidistantly mutually spaced along the shaft 22 by the spacer rings 32. A 
plurality of exhaust openings 33 are formed through each disc 21, in an 
annular, concentric array and at mutually spaced intervals around the 
shaft 22. The openings 33 are adjacent to but spaced radially beyond the 
spacer rings 32. Preferably, the discs 21 are angularly aligned upon the 
shaft 22 with their exhaust openings 33 in mutual alignment, in register, 
whereby continuous exhaust flow passageways are defined through the 
exhaust openings 33, extending parallel to and alongside the shaft 22. 
First and second annular partitions 34, 35 are fixedly mounted within 
opposite end portions of the housing 11, spaced inwardly from the endwalls 
17, 18, respectively. Cylindrical spacer rings 36 extend between the 
endwall 17 and partition 34, and between the endwall 18 and the partition 
35, and are aligned coaxially around the shaft 22. Exhaust openings 33' 
are formed through the partitions 34, 35, in alignment with the exhaust 
openings 16 formed through the endwalls 17, 18, at locations spaced 
radially within the cylindrical rings 36 and in radial alignment with the 
openings 33 formed through the discs 21. The end portions of the 
cylindrical rings 36 are preferably affixed to the repective adjacent 
endwalls 17, 18 and partitions 34, 35, whereby an exhaust flow pathway is 
formed through the partitions and endwalls within the cylindrical rings 
36, in radial alignment with the exhaust openings 33 formed in the discs 
21. The exhaust ducts 14, 15 communicate with the exhaust openings 16 of 
the respective endwalls 17, 18 through first and second cylindrical 
manifolds 40, 41, (FIG. 3) respectively, which are affixed to the housing 
endwalls 17, 18, respectively, to define cylindrical manifold chambers 
communicating between the exhaust openings 16 and the exhaust ducts 14, 
15. The exhaust ducts 14, 15 extend tangentially from the manifolds 40, 41 
and communicate with the manifold chambers through corresponding openings 
formed through the sidewalls of the manifolds. 
The housing and duct components are suitably bonded or bolted together by 
conventional fastening means in low temperature areas. In high temperature 
regions, however, conventional fastening means are not sufficient. The 
components are preferably formed integrally, or formed as component parts 
which are bonded together by the application of an uncured phenolic resin 
as a bonding agent, and then subjected to curing and pyrolization 
processes, for producing an integral assembly. As viewed in FIG. 7, for 
example, the second endwall 18 is formed integrally with the cylindrical 
housing 11, and the first endwall 17 is fastened in place by reinforcing 
pins 39. It is preferably further secured by the above-described bonding 
and pyrolization process. During assembly of the components, the rotor 
structure 20 is installed prior to installation of the endwall 17 and the 
intermediate partition 34. An anti-oxidation coating is applied to 
surfaces subject to high temperatures in operation, including the surfaces 
of the reinforcing pins 39. If the apparatus is to be used in an 
application such as expendable missile or the like having a brief 
operational cycle, less stringent assembly and coating procedures may be 
employed. 
High temperature journal bearings 43 (FIG. 7), are seated within the outer 
sidewalls of the first and second cylindrical manifolds 40, 41, where they 
can be conveniently cooled and lubricated, and the shaft 22 is rotatably 
and sealingly fitted within the bearings 43 for preventing any substantial 
leakage of gaseous flow from the housing chamber 19 around the shaft 22. 
It is generally preferable that the total exhaust area provided by the 
disc exhaust openings 33 be substantially equal to that of the outlets 16, 
and to the respective cross-sectional areas of the outlet ducts 14, 15. 
The rotor structure 20 is maintained in a central position within the 
housing 11, and prevented from any substantial longitudinal translation, 
suitably means of thrust bearings 25 and 26 (FIG. 3) mounted on the 
pedestals 27, 28. Alternatively, suitable locking washers or keys, not 
shown, are provided on the end portions of the shaft 22 external of the 
housing 11, adjacent the thrust bearings 25, 26, for preventing lateral 
displacement of the shaft 22 and rotor structure 20. A slight gap is 
provided between the end discs 21 and the inwardly facing side surfaces of 
partitions 34 and 35 to prevent unwanted friction or wear. 
With additional reference to FIGS. 5 and 6, the inlet duct 13 is preferably 
of generally rectangular cross section and extends tangentially of the 
housing 11. The inlet duct 13 communicates between a supply of gas under 
pressure, not shown, and the housing chamber 19 through a corresponding 
inlet opening 45 formed through the housing 11 and extending 
longitudinally along the length of the housing 11. As may be seen in FIGS. 
5 and 6, the inlet duct 13 is in substantial alignment with the peripheral 
portions of the discs 21, whereby inflowing gases may be directioned 
tangentially against the peripheral portions of the discs. As may be seen 
more clearly in FIG. 6, an inlet throat area 46 is defined between the 
inlet duct 13 and the interior of the housing 11. The throat area 46 is 
not of an expanding cross-sectional area relative to the inlet duct, but 
instead provides a continuation of the inlet 13 as it merges into the 
chamber 19. The upper interior surface area 47 of the housing 11 merges 
quickly inwardly toward the rotor structure 20, whereby the propulsive 
gasses are merged into the rotor structure 21 within one quarter of the 
circumference of the discs 21. As seen most clearly in FIG. 5, the upper 
wall portion of the housing 11, which defines the upper wall surface 47, 
is preferably curved slightly outwardly beyond a precisely cylindrical 
configuration, to enlarge the inlet opening 45 and permit rapid merging of 
the inlet flow into the rotor structure 20. The housing 11 is nevertheless 
of substantially cylindrical configuration. With additional reference to 
FIGS. 4b and 4a, a plurality of flow divider vanes 50 are affixed to the 
upper surface area 47, in mutually parallel alignment and in register with 
respective adjacent ones of the discs 21. The vanes 50 project radially 
inwardly from the upper surface area 47 of the housing 11 and are tapered, 
from their leading edges (which confront the inlet duct 13) toward their 
trailing edge portions. The vanes 50 extend parallel to and immediately 
adjacent the peripheral edges of respective ones of the discs 21. The 
leading areas of the vanes 50 are narrowed, in knife-edge configuration 
and, as seen in the drawing, they extend rearwardly as respective 
divergent/convergent airfoils, as seen most clearly in FIG. 4b. 
The purpose of the vanes 50 is to divide the inflowing gasses into 
segregated inlet channels 51 with as little turbulence as possible as the 
gases pass through the inlet throat area 46 and into the spaces formed 
between the discs 21. Turbulence is minimized because the gasses are not 
permitted to expand significantly prior to their entry into the rotor 
structure 20 and, secondly, because the inlet channels 51 (FIG. 4a) 
defined by the throat 46, vanes 50, the confronting discs 21, and the 
upper surface area 47 act to smoothly divide the gasses into individual 
flow paths in register with respective ones of the annular spaces between 
the discs 21. 
With additional reference to FIG. 5, the interior surfaces of the inlet 
duct 13 and housing 11 are subjected during operation to high pressure 
gaseous flow driven along the duct 13 toward the housing 11 under high 
pressures from a gas generator, not shown, and subsequently conducted 
through the housing opening, as seen more clearly in FIG. 6, tangentially 
toward the rotor structure discs 21. Operation of the apparatus will be 
described in more detail in later sections. As has been suggested in the 
previous discussions of the prior art, however, at temperatures above 
1800.degree. F., available metals and alloys begin to suffer deterioration 
and deformation in such rotor structures. Modern turbines employ high 
temperature resistant nickel and cobalt alloys, but any increase above 
such temperature ranges results in deleterious effects, even to such 
alloys. As suggested above, however, propulsive gasses at higher 
temperatures are of higher energy levels and can produce significantly 
higher efficiencies in such disc-type turbines. Thus, in accordance with 
the present invention, those portions of the turbine apparatus 10 which 
are exposed to high temperature propulsive gases are formed of composite 
materials, of sufficient thermal stability and toughness to sustain the 
thermal and physical stresses entailed, including the vibrational and 
centrifugal forces sustained at very high rotational velocities of the 
rotor structure. 
To summarize, because of the high thermal and physical stresses entailed, 
it has previously been impossible to manufacture practicable turbine 
apparatus operable at the high efficiencies obtainable above the 
1500.degree.-2000.degree. F. temperature range. It has been impracticable 
to employ carbonized composite materials in turbine/pump apparatus. In 
accordance with an important aspect of the preferred embodiment of the 
present invention, however, carbonized composite structures are employed 
for the high temperature components of the system. As suggested earlier, 
conventional turbine components are of such complexity that they are not 
readily formed of such composite materials. Accordingly, the present 
apparatus is of a construction which does not incorporate conventional 
turbine construction, but incorporates a combination of components 
particularly adapted for practicable construction and assembly from 
carbonized composite panels, sheets, and rods. Further, the assembly and 
bonding techniques described above permit manufacture of the 
multicomponent turbine apparatus 10 as a rugged unit capable of sustaining 
the mechnical and thermal loads. As discussed above, the manufacturing 
methods for forming the individual component parts of such "carbon carbon" 
composite structures are known in the art and therefore will not be 
described in detail herein. It is significant however, that the assembly 
and rotor structure 20 are of a configuration particularly suited for 
formation by such processes, because of the absence of vanes, blades, and 
buckets or the like on the peripheral areas of the discs, and because the 
rotor structure 20 may be readily assembled from non-detailed, symmetrical 
components. Additionally, the discs may be constructed with continuous 
fibrous reinforcement of optimal configuration as integral, planar 
workpieces, and thereby attain the substantial structural integrity under 
high rotational velocities and temperatures which is required for the 
environment entailed. 
Continuing the description of the preferred embodiment, with reference to 
FIGS. 2 and 5, the inlet duct 13 is suitably of approximately rectangular 
cross-section and, as stated above, communicates tangentially with the 
interior of the housing 12 through the rectangular opening 45 formed 
through the side of the cylindrical housing 11. Because no enlarged cavity 
is interpositioned between the inlet duct 13 and the housing interior, 
expansion of the injected gases occurs substantially entirely within the 
spaces intermediate the discs, rather than in an inlet cavity or manifold. 
In operation, propulsive gasses, typically under widely varying pressures, 
are conducted through the inlet duct and throat area 46 from a gas 
generator, not shown, through the channels 51 (FIG. 4a) and directly into 
the annular spaces defined between the discs 21. The continuous, gradual 
curvature defined by the upper wall surface 47 conducts the flow smoothly 
around the peripheral regions of the discs 21, whereby tangential and 
radial forces, derived from reactive and viscous engagement of the gases 
with the mutually confronting disc surfaces, induce rotational movement of 
the rotor structure 20 upon the bearings 25, 26. Gas under pressure is 
diverted by the upper surface 47 and caused to flow around the cylindrical 
housing chamber 19 and is caused to follow a spiral flow path due to the 
negative pressure gradient toward the central region of the chamber 19, 
from which it exits through the exhaust channels defined through the 
outlets 33, 33', and the outlets 16, into the exhaust manifolds 40, 41, 
and subsequently through the exhaust ducts 14, 15. Because the inflowing 
gases are of a substantial pressure and energy level, they react 
efficiently with the peripheral regions of the rotor discs. As the gases 
flow spirally, radially inwardly, and subsequently through the exhaust 
openings 33 and the exhaust ducts 14, 15, their energy levels and 
temperature are substantially reduced. 
The power output of the apparatus is dependent upon a number of design 
variables, including the flow rate, pressure, and temperature of the 
propulsive gasses, the inlet passageway and outlet areas, and the number, 
diameter, and mutual spacing of the discs. The dimensions of the 
components will therefore relate to the operating envelope of the specific 
application. the design and adaptation of the specific rotor structure of 
such Tesla turbines and pumps for achieving desired operating outputs is 
accomplished by techniques known to those in the art, as typified by the 
study detailed in the article of Dr. Warren Rice, pages 253 to 258, 
Journal of Fluids Engineering, September 1974. Because of the multiplicity 
of design parameters, empirical adjustments of the rotor disc spacings are 
advantageously employed for refinement of operation for a particular 
application. Output is generally increased as the number and diameter of 
the discs is increased, as the spacing between the adjacent discs is 
lessened, and as the gas flow velocity is increased. 
As previously discussed, the efficiencies of such apparatus are sharply 
reduced when the flow velocity of the inflowing propulsive gases falls 
below a nominal range. In operation, this sharp drop in power output 
normally renders such Tesla apparatus difficult to control under varying 
power levels, in that a relatively minor reduction in mass flow rate may 
precipitate a substantial loss of output. Conventional Tesla turbines are 
thus undesirably sensitive to variations in flow rate, and it is extremely 
difficult to obtain a gradual throttling of the rotational velocity by 
controlling the mass flow rate, or to provide a relatively constant 
velocity under varying loads by varying mass-flow rate. 
In the preferred embodiment of the present invention, however, means are 
provided for maintaining the gas flow velocity at a substantially constant 
level as the total mass flow rate is varied. With primary reference to 
FIG. 2, a flow control apparatus 54 is provided for permitting the 
application of propulsive flow to all of the discs, or to only a portion 
of the rotor structure 20, as the mass flow rate is varied. The flow 
control apparatus 54 employs an elongated, directionable guidewall 55 
which is mounted within the inlet duct 13, with its width projecting 
substantially between the upper and lower duct walls. (Directional terms 
such as "upper", "lower" and the like are employed herein with reference 
to the drawing for ease and clarity of description, and are of course not 
to be interpreted as suggestive of a single orientation or operational 
mode for the turbine apparatus 10.) In its preferred embodiment, the 
directionable guidewall 55 is constructed of an elongated, generally 
rectangular sheet of carbonized composite material extending upstream 
within the inlet duct 13, from the housing inlet opening 45 toward a 
mounting block 56 which is affixed in an upright position within the duct 
13 adjacent one side of the duct. The mounting block 56 is suitably a 
sheet of composite material connected between the upper and lower duct 
walls and extending parallel to the duct axis. Clevis 57 is suitably 
formed on the downstream end of the mounting block 56, and a plate member 
60 is slidably mounted within the clevis 57. The upstream end portion of 
the directionable guide wall 55 is pivotally connected to the plate 60 by 
a vertically extending hinge structure 61, also formed of carbonized 
composite material and employing a composite rod as a shaft, whereby 
pivotal movement of the guide wall 55 within the duct 11 is permitted 
about this vertical axis upon the hinge 61. The guidewall 55 is vertically 
oriented within the duct 13 and extends loosely between the upper and 
lower duct walls for effecting a substantially fluid sealed association 
between the upper and lower duct walls, but with sufficient upper and 
lower clearance to permit lateral pivotal movement of the guide wall 
within the duct. The opposite, downstream end portion of the guidewall 55 
is pivotally connected, by a hinge structure 62 similar to hinge 61, to a 
slideable valve gate structure 64 which is mounted for lateral sliding 
movement within the housing inlet opening 45. 
As seen more clearly in FIG. 6, the slideable valve gate structure 64, in 
cross section, is formed substantially as a moveable section of the 
cylindrical housing wall, extending, in width, across the housing inlet 
opening circumferentially across the adjacent portions of the rotor discs 
21, and extending longitudinally substantially along the width of the 
rotor structure 20, when positioned fully extended across the opening 45. 
In cross section, the inner, arcuate surface 65 of the gate structure 64 
is substantially shorter than the outer surface 66, and first and second 
edge surfaces 67, 68 are preferably disposed along mutually diverging 
planes; the surfaces 67, 68 suitably extend along substantially 
perpendicular axes. Corresponding, first and second angular cutout 
surfaces 70, 71 are formed in the housing 11, extending along the length 
of the inlet opening 45 for defining mating surfaces against which the 
gate structure end surfaces 67, 68 are slideable seated, and for providing 
an interlocking relationship between the gate structure 64 and the housing 
11, constraining the gate structure within the housing opening and 
prventing any excessive flexing of the structure 64 under lateral loads, 
while permitting slideable movement of the structure longitudinally along 
the longitudinal axis of the opening 45. 
During operation, loads which are exerted against the valve gate structure 
64 by fluid pressures within the inlet duct 13 tend to urge the gate 
structure rearwardly toward the housing 11, whereby rearward loads are 
transferred primarily to the vertical segment of the second cutout section 
71, and secondarily against the first cutout section 70. Bending and 
torque stress loads on the valve gate structure are thereby substantially 
minimized by interlocking relationships of the gate structure 64 against 
the slideable tracks 70, 71. 
The valve gate structure 64 has a first end portion having a 
perpendicularly projecting mounting flange 73 formed thereon, extending in 
a plane parallel to the discs 21 and the plate member 60, to which the 
upstream end portion of the directionable guide wall 55 is hingedly 
connected. The hinge structure 62 is mounted vertically on the mounting 
flange 73, whereby the directionable plate member 55 is caused to sweep 
generally pivotally across the inlet duct 13 in response to longitudinal 
movement of the valve gate structure 64. Such movement also translates the 
plate member 60 axially, inwardly within the clevis 57, upon the plate 50 
when approaching an intermediate position (in which the plate 55 extends 
perpendicularly from the gate 55 and the housing longitudinal axis.) The 
valve gate structure 64 is longitudinally translatable between a first, 
projected position, which lies beyond that shown in solid lines in FIG. 2, 
in which it extends across a majority of the discs, (e.g., in which it 
covers approximately 90 percent of the length of the inlet area, and a 
second, retracted position, as shown in broken lines in FIG. 2, in which 
it is withdrawn from the rotor structure and in which the housing inlet 
duct 45 is unobstructed along the length of the rotor structure. In the 
retracted position, the second end portion of the valve gate 64, and the 
actuator rod, project outwardly from the housing 11 within an actuator 
housing 79, which communicates with and projects laterally from the inlet 
duct 13. 
As may be seen in FIG. 2, an inlet duct channel or passageway 75 is defined 
within the inlet duct 13, between the upper and lower duct walls, and 
between the moveable, directionable guide wall 55 and a confronting, fixed 
sidewall partition 76 extending longitudinally of the duct along its side 
opposite the directionable guide wall. When the valve gate 64 is in its 
retracted position, in which the housing inlet 45 is fully opened, the 
duct passageway 75 is of a divergent cross section, diverging along its 
length toward the inlet 45. When the gate 64 is conversely positioned in 
its projected position, the passageway 75 converges toward the inlet 45, 
for reasons which will be understood from the description hereinbelow. 
The gate structure 64 and guidewall 55 are positioned by an actuator, now 
shown, through an actuator shaft 77 which has its distal end portion 
connected to the guidewall 55 by means of a hinge structure 78 mounted on 
the mounting flange 73. The actuator is suitably mounted in an actuator 
housing 79, affixed to a side portion of the duct 13 and suitably 
supported by a portion of the pedestal structure 27, and extending 
outwardly from the adjacent sidewall of the inlet duct 13. A power takoff 
gearing and transmission apparatus, not shown, is connected to the rotor 
shaft as required for the particular application. 
In operation, the valve gate structure 64 is retracted to its open position 
during operation under fully powered conditions, i.e., during substantial 
inflowing gaseous flow at or above a range at which the turbine 10 is most 
efficiently operable. As has been previously discussed, when the gaseous 
flow velocity intermediate the rotor discs 21 falls below the optimal 
range, the efficiency and rotational velocity of the turbine decreases 
sharply. Such an effect is prevented, in the present system, by 
translating the valve gate structure 64 to its projected position, wherein 
the directionable guidewall 55 is pivoted in a counterclockwise direction, 
as viewed in FIG. 2, wherein the inlet duct passageway 75 converges toward 
a relatively narrow portion of the housing inlet opening 45. The flow 
velocity of the inflowing gas passing through the inlet 45 is thereby 
increased, because of the reduced area of the inlet 45 and because of the 
smoothly converging flow path 75, and the gaseous flow which is conducted 
to react with the discs 21, adjacent the portion of the inlet 45 which 
remains open to the duct 13, is thus maintained at a relatively constant 
flow velocity despite a reduction in the net mass flow rate through the 
duct 13. It will be understood that the net output torque or power 
available from the rotating disc structure 20 decreases as the inflowing 
mass flow rate decreases, in that the gaseous flow is applied only to a 
portion of the rotor structure 20. In effect, only a portion of the discs 
are then operable. However, the flow velocity of gasses which are directed 
to the selected percentage of the rotor discs is substantially higher than 
would be the case if the reduced mass flow were applied to all of the 
discs. Because of the exponential increase in efficiency of such turbines 
as the gas flow rate is increased, within a nominal operating range, the 
high flow velocities applied only to a few of the discs provides an 
available, usable output which is substantially higher than that which 
would be obtainable by applying the reduced total mass flow to all of the 
discs, at a lower flow velocity. 
During operation under normal loads, the system is operable to provide a 
gradual, controllable decrease in output velocity as the flow rate is 
decreased, providing a non-exponential, proportional relationship between 
inlet mass flow rate and output velocity. Similarly, the flow control 
apparatus 54 may be employed to provide a variable torque output which may 
correspond with a variable load condition, in which it is desired to 
maintain a constant velocity under varying load conditions. 
Whereas, the discussion thus far has referred largely to the use of the 
system as a gas-driven turbine, it will be understood from the initial 
discussion of the Tesla U.S. Pat. No. 1,061,142 that the apparatus may 
also be employed as a fluid pump, wherein motive energy is applied in the 
form of torque applied by an external motor to the drive shaft for 
rotating the rotor structure 20 in a reversed, counter-clockwise direction 
as viewed in the drawing. Fluid within the housing, between the rotor 
discs, is driven in a rotational direction, along an outward spiral path, 
and ejected tangentially outwardly through the (outlet) 45 and along the 
duct 13. Because of the resultant pressure drop within the chamber 19, 
fluid is pumped into the chamber through the ducts 14, 15. The variable 
flow control apparatus 54 is advantageously operable to vary the number of 
operable discs 21, i.e., discs reacting with the fluid, whereby efficient 
flow velocity may be maintained through the housing during a condition in 
which total flow is reduced, when it is desired to reduce total flow but 
to maintain pumping efficiency. Such a pumping apparatus, when constructed 
of the carbonized composite materials discussed above, is uniquely suited 
for pumping fluids at very high temperatures. 
A control system 72 (FIG. 8) is provided for controlling the position of 
the valve gate structure 64 and guidewall 55 in response to varying fluid 
flow conditions. With reference to FIG. 8, a microprocessor 80, which is 
suitably a Hewlett Packard Model 3054C computer based data acquisition and 
control system having a model 3497A data acquisition and control unit, a 
3456A digital voltmeter, and a 3437A system voltmeter, is provided. The 
ROM unit is programmed with an algorithm adapted to process signals 
derived from flow condition sensors mounted within the inlet and outlet 
channels, for providing an output signal to a servocontrol and position 
transducer device 81 connected to the actuator, for commanding the 
actuator to position the valve gate structure 64. A first sensor set 82 
which includes sensor elements responsive to pressure, flow velocity, and 
temperature, is mounted within at least one of the outlet ducts 14, 15, 
and its output is fed to the microprocessor through a multi-conductor 
cable 84. A second, similar sensor set 83 is also installed within the 
outlet duct 14, and its output is fed to the servocontrol 
transducer/sensor 81. A velocity sensing transponder 93 is mounted 
external the housing adjacent the shaft 22 for providing an output signal 
corresponding to shaft rotational velocity and torque, for transmitting 
digitally encoded signals to the microprocessor 80 through cable 85. A 
third sensor set 87 is mounted in the inlet duct 13 providing signals to 
the microprocessor 80, through conductor 88, indicative of inlet fluid 
temperature, flow rate, and pressure within the inlet duct 13. 
Referring additionally to FIG. 9, a flow diagram is employed which is 
repesentative of the data flow paths entailed in a typical embodiment of 
the processor circuit. The processor 80 of FIG. 8 is represented in its 
several functions, as encompassing feedback elements 91, a comparator 89, 
and the actuator servocontroller 81 (FIG. 8). The comparator 89 is a 
comparator circuit which functions as an error signal sensor, receiving 
inputs through conductor 88 (FIG. 8) from the inlet sensor set 87. The 
comparator 89 compares the inlet condition signals derived through data 
link conductor 88 with signals derived through data link conductor 86, 
which is part of a feedback loop for receiving signals derived from the 
shaft output sensor 93 through conductor 85, and signals derived from the 
outlet duct sensor sets 82, 83, all of which are fed through a feedback 
processing circuit 91 which translates the raw signal received from the 
sensor into a digitally encoded signal format. The comparator 89 is a 
multifunction device operating to calculate percent error signal 
corresponding to the respective differences between the inlet and outlet 
temperatures, pressures, and flow rates, and to transmit output signals 
corresponding to the respective error signals, and to the shaft velocities 
and torque, to a function generator 80. The function generator 80 
incorporates the processor controlling hardware and software, including 
algorithms for cyclically processing the data. The algorithms are suitably 
derived as those described in the previously referenced article of Dr. 
Warren Rice, appearing in the American Society of Mechanical Engineering 
Journal of Fluid Engineering. The function generator solves the algorithms 
to provide two outputs relating to the turbine operation, corresponding to 
the actual and optimal delta values between the inlet and outlet sensors, 
for the current flow and load conditions. The equations are cyclically 
solved, and differences between the optimal and actual values are entered 
into the processor 80 which provides position correction commands, in 
accordance with permanently stored algorithms, to a controller 90. The 
controller processes and amplifies the position correction signals and 
provides command signals to the actuator servocontrol 81. 
The processor 80 may be programmed to provide an optimal power output under 
given inlet conditions, or alternatively, to provide a substantially 
constant shaft velocity, under varying conditions, and thereby provides 
substantial versatility of operation. An alternative, mechanical control 
apparatus, not shown, which is less versatile and precise but which 
provides a degree of operative control for less critical applications, 
incorporates a spring which is connected for continuously urging the valve 
gate structure toward its projected position (in which the housing inlet 
opening is substantially closed.) Suitably, a spring is connected between 
the actuator rod 77, and structure fixed relative to the housing, under 
compression or tension, for urging the valve gate toward its projected 
position. Preferably, the spring is positioned external of the high 
temperature regions, suitably in the housing 79. The spring has a spring 
rate sufficient to deploy the gate structure in its projected position 
under low mass flow rate conditions, but not sufficient to overcome 
gaseous pressure within the duct 13 exerted against the directionable 
guide wall during higher mass flow rate conditions under which the gate 
structure is optimally positioned in its retracted position. Accordingly, 
gaseous pressures during such high flow rate conditions exert forces 
against the directionable guide wall urging it rearwardly and retracting 
the valve gate structure, overcoming the oppositely directioned forces 
exerted by the spring. Thus, opening and closing of the valve structure is 
effected in a manner suitable for non-critical applications, in which 
precise control of the gate position is not required. 
Exemplary applications of the apparatus include use in a gas turbine 
engine, in an aircraft or vehicular power plant, or as a power take-off 
turbine, as in in an automobile turbocharger system. In the latter 
application it is connected in series with the exhaust manifold and 
drivingly connected to a compressor pump, for delivering compressed air to 
the carburation system. When the apparatus is employed in such an 
automobile supercharger system, the increased rotational velocity attained 
even at reduced inlet flow rates maintains a substantial pumping action 
and resultant air pressure at the carburator during idling conditions, 
whereby there is no "supercharger lag" during initial acceleration from 
idle. 
It can now be seen that the invention provides an efficient apparatus for 
translating motive energy into an alternative form. When employed as a gas 
driven turbine, the apparatus provides an efficient conversion of fluid 
flow and pressure into mechanical energy in the form of rotational output 
derived at the shaft 22. When employed as a pump, the apparatus is 
effective to translate rotational energy into fluid flow, and is operable 
under a variety of temperature and fluid conditions. When the apparatus is 
employed as a turbine, it obviates many of the difficulties previously 
experienced in the operation of turbines of the rotational disc type. The 
continuously adjustable inlet flow control means 54 provides enhanced 
efficiency and versatility of operation under varying operational regimes, 
and in the projected position, the converging inlet duct, in combination 
with the retricted area inlet, provides substantially increased 
efficiency. The use of planar rotor discs rather than bladed rotors and 
the use of component structures particularly adapted for carbonized 
composite materials, permits the substantial use of carbonized composite 
materials, permitting practicable operation at temperatures substantially 
in excess of 1800.degree. F., thereby further enhancing operational 
efficiency. Because of the substantial use of planar sheet components as 
moveable elements in the apparatus, and the use of 
bonding-curing-pyrolization bonding procedures for joining the components, 
optionally supplemented by the composite pins, practicable, relatively 
inexpensive construction of the apparatus with composite materials is made 
possible. The system may thus be made operable at substantially higher 
temperatures than those employed in conventional turbines. Because of the 
high strength to weight ratio of carbonized composities, substantial 
rotational velocities are permitted, and warpage and thermal expansion of 
the parts are minimized because of the thermal stability of the materials. 
It will further be appreciated by those in the art that because of the 
substantially constant cross-sectional area of the duct 13 and the throat 
45, and because of the direct injection of the inlet flow between the 
rotor discs 21, efficiency losses are minimized, in that expansion of the 
gasses occurs substantially within the rotor structure 20. As suggested 
above, the flow divider vanes in register with the rotor blades, and the 
smoothly contoured upper deflecting surface 47, further reduce turbulence 
and resultant energy losses, in that the flow is smoothly channeled into 
the spaces 51 between the discs. 
Accordingly, the particular turbine construction, employing multiple rotor 
discs of a carbonized composite material, permits the high efficiency 
outputs obtainable only from high temperture gaseous flow substantially in 
excess of 1800.degree. F., and the variable flow control system 54 permits 
versatile, practicable operation of such a multiple rotor disc structure. 
While only two embodiments of the invention, together with modifications 
thereof, have been described in detail herein and shown in the 
accompanying drawing, it will be evident that various further 
modifications are possible in the arrangement and construction of its 
components without departing from the scope of the invention.