UNITED STATES PATENT AND TRADEMARK OFFICE
`______________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`______________
`
`GENERAL ELECTRIC COMPANY,
`Petitioner
`
`v.
`
`UNITED TECHNOLOGIES CORPORATION,
`Patent Owner
`______________
`
`Case No. IPR2016-00534
`Patent 8,365,513
`______________
`
`DECLARATION OF ERNESTO BENINI
`
`
`
`
`
`
`
`
`
`UTC-2009.001
`
`GE v. UTC
`Trial IPR2016-00534
`
`
`______________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`______________
`
`GENERAL ELECTRIC COMPANY,
`Petitioner
`
`v.
`
`UNITED TECHNOLOGIES CORPORATION,
`Patent Owner
`______________
`
`Case No. IPR2016-00534
`Patent 8,365,513
`______________
`
`DECLARATION OF ERNESTO BENINI
`
`
`
`
`
`
`
`
`
`UTC-2009.001
`
`GE v. UTC
`Trial IPR2016-00534
`
`
`
`I.
`
`
`Introduction
`
`I, Ernesto Benini, declare as follows:
`
`1.
`
`I have been retained on behalf of United Technologies Corporation to
`
`offer technical opinions relating to U.S. Patent No. 8,365,513 (the ’513 Patent),
`
`and prior art references relating to its subject matter.
`
`2.
`
`In forming my opinions expressed in this declaration, I have relied on
`
`my education and experience in both academia and in consulting for industry. I re-
`
`viewed the ’513 patent and its prosecution history. I have also reviewed the Peti-
`
`tion and accompanying exhibits.
`
`3.
`
`I am being compensated at the rate of 114 Eur/hour for my work in
`
`this matter.
`
`II. Qualifications
`
`4. My name is Ernesto Benini. I am a Professor in Mechanical Engineer-
`
`ing at Padova University in Padova, Italy. My current curriculum vitae is attached
`
`as UTC-2010.
`
`5.
`
`I earned my MSc. (1996) in Mechanical Engineering and my Ph.D.
`
`(2000) in Energy Technology from Padova University. My main research interests
`
`include turbomachinery, propulsion, jet engines, and optimization techniques. I
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`have also done work in artificial intelligence, computational fluid dynamics (CFD)
`
`
`
`1
`
`UTC-2009.002
`
`
`
`of internal and external flows, incompressible, compressible and reacting flows,
`
`and aeroelasticity in turbomachines.
`
`6. My professional affiliations include Member ASME (American So-
`
`ciety of Mechanical Engineers), AIAA (American Institute of Aeronautics and As-
`
`tronautics), AHS (American Helicopter Society), ETN (European Turbine Net-
`
`work), Working Group “Condition Monitoring, Instrumentation and Control”,
`
`AHS (The Vertical-Flight Technical Society, formerly American Helicopter Socie-
`
`ty).
`
`7.
`
`I have received the Best Paper Award in Propulsion, AHS American
`
`Helicopter Society, “A New Methodology for Determining the Optimal Rotational
`
`Speed of a Variable RPM Main Rotor/Turboshaft Engine System”; Best Paper
`
`Award, IAENG International Conference on Systems Engineering and Engineering
`
`Management 2012, San Francisco, CA, “GeDEA-II: A Novel Evolutionary Algo-
`
`rithm for Multi-Objective Optimization Problems Based on the Simplex Crossover
`
`and The Shrink Mutation”; and “2012 Outstanding Reviewer”, Journal of Energy
`
`Engineering (http://ascelibrary.org/journal/jleed9).
`
`8.
`
`I am the author and co-author of 250 scientific papers on international
`
`peer-reviewed journals and congresses.
`
`
`
`2
`
`UTC-2009.003
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`
`
`9.
`
`In particular, my extensive experience with fans, the design of fans,
`
`and optimization techniques for improving the efficiency of fans/engines in opera-
`
`tion is applicable to an analysis of the ’513 patent.
`
`III. Legal Standards
`
`10.
`
`It is my understanding that there are two ways that prior art references
`
`can render a patent invalid: anticipation and obviousness. Counsel told me that Pe-
`
`titioner has the burden in an IPR to show anticipation or obviousness by a prepon-
`
`derance of the evidence.
`
`11.
`
`I also understand that there is a set process as follows: a) the claims of
`
`a patent are properly construed, b) then, you must compare the claim language to
`
`the prior art on a limitation-by-limitation basis. If the prior art reference contains
`
`all the elements of the claim language (explicitly or inherently), arranged as in the
`
`claims, then that is considered anticipation.
`
`12.
`
`I understand that an invention is obvious when the differences be-
`
`tween the subject matter sought to be patented and the prior art are such that the
`
`subject matter as a whole would have been obvious at the time of the invention to a
`
`person having ordinary skill in the art. For this reason, I have been asked to con-
`
`sider the level of ordinary skill in the field that someone would have had at the
`
`time of the claimed invention.
`
`
`
`3
`
`UTC-2009.004
`
`
`
`13. Counsel has also instructed me that in an obviousness determination
`
`the factors to consider are: (1) the scope and content of the prior art, (2) the differ-
`
`ences between the prior art and the asserted claims, (3) the level of ordinary skill in
`
`the pertinent art, and (4) the existence of secondary considerations. Secondary con-
`
`siderations include: a long felt need; commercial success; unexpected results;
`
`praise of the invention; licensing; copying; failure of others; and skepticism by ex-
`
`perts.
`
`14. Counsel has also instructed me that an obviousness inquiry may in-
`
`volve assessing the motivation of a person of ordinary skill to combine references.
`
`The prior art references themselves may provide a suggestion, motivation, or rea-
`
`son to combine, but other times the rationale for combining two or more prior art
`
`references may be common sense.
`
`15.
`
`It is also my understanding through counsel that the combination of
`
`familiar elements according to known methods is likely to be obvious when it does
`
`no more than yield predictable results. It is further my understanding that a proper
`
`obviousness analysis focuses on what was known or obvious to a person of ordi-
`
`nary skill in the art, not just the patentee.
`
`16.
`
`I have been informed that claim terms in the ’513 patent must be giv-
`
`en the broadest reasonable interpretation. Such an interpretation still has to be con-
`
`
`
`4
`
`UTC-2009.005
`
`
`
`sistent with the patent’s specification and with usage of the terms by one of ordi-
`
`nary skill in the art at the time of invention.
`
`17.
`
`I have used October 12, 2006, which is the filing date of the ’513 pa-
`
`tent, as the time of the invention.
`
`IV. Level of Ordinary Skill in the Art
`
`18.
`
`In my opinion, a person of ordinary skill in the art is a professional
`
`who earned at least a Masters Degree in either Mechanical or Aerospace Engineer-
`
`ing, as well as at least three years of experience, after the obtainment of the Mas-
`
`ters, in the field of gas turbine engine design.
`
`V. The ’513 Patent and Claim Terms
`
`A. The ’513 Patent
`19. The ’513 patent issued on February 5, 2013, and discloses a separate-
`
`flow turbofan engine. The turbofan engine described in the ’513 patent includes
`
`low pressure and high pressure compressors, a combustor, and high and low pres-
`
`sure turbines. (’513 patent at 2:21-40.) In the ’513 patent’s turbofan, the low pres-
`
`sure turbine drives a fan. (’513 patent at 2:18-20.) A fan is a bladed turbomachine
`
`which compresses the air intercepted by an engine intake and provides such com-
`
`pressed air to a core engine as well as to a bypass duct.
`
`20. A separate-flow turbofan engine drives air through two primary, sepa-
`
`rated, paths: a core flowpath, where combusted gasses expand across the turbine
`
`
`
`5
`
`UTC-2009.006
`
`
`
`and drive the fan, and a bypass flowpath, where the fan generates most of its thrust
`
`by forcing air through a bypass duct. (’513 patent at 2:48-52.) The nozzle at the
`
`rear of the bypass duct defines a nozzle exit area. I provide below an annotated
`
`version of Figure 1 that shows both flowpaths, the fan, and the nozzle exit area.
`
`
`
`(’513 patent at FIG. 1 (annotated).)
`
`21. Every fan has an operating line. An “operating line” describes the
`
`pressure ratio and mass flow rate that a fan will possess under specified conditions.
`
`(’513 patent at 1:17-27.) Because the fan’s pressure ratio and mass flow rate are re-
`
`lated to an engine’s thrust, an operating line helps describe and predict an engine’s
`
`performance under a variety of conditions.
`
`
`
`6
`
`UTC-2009.007
`
`
`
`22. A fan’s operating line is typically represented in a fan map, which
`
`provides information regarding pressure ratio, mass flow rate, efficiency, and fan
`
`speed for a given fan. In order to represent a fan’s operating line independent from
`
`external boundary conditions (in particular ambient pressure and temperature),
`
`such maps are graphically represented in a way that the compressor ratio is drawn
`
`as a function of the corrected delivered mass flow rate and the corrected rotational
`
`speed. Thus, when I refer to mass flow rate or rotational speed in the context of a
`
`fan map in this declaration, I am referring to the corrected values.
`
`23. An operating line for an exemplary fan is highlighted in green in the
`
`figure below. In the figure, the operating line is the dash-dot line, and the mass
`
`flow rate (
`
`) is defined along the x-axis while the pressure ratio (πf) is de-
`
`fined along the y-axis. The turbofan pressure ratio is the ratio of the total pressure
`
`on the back side of the fan, P2, to the total pressure in front of the fan, P1. (’513
`
`patent at Fig. 1, 3:33-34.) The corrected mass flow rate refers to the mass of a sub-
`
`stance (in this case air) that passes per unit of time, corrected to assume that the in-
`
`let pressure and temperature correspond to specific ambient conditions at sea level.
`
`
`
`7
`
`UTC-2009.008
`
`
`
`L5
`
`fir
`
`L3
`
`Pressure
`
`Ratio
`
`40
`
`60
`
`80
`
`100
`
`120
`
`% design n’z2\l4T2/52
`
`Corrected Mass Flow Rate
`
`(GE—1014.088, Fig. 9-39 (color armotation added).)
`
`24. A fan installed in a turbofan engine will operate at different points
`
`along its operating line based on the throttle input. (GE-1014.078.) An increase in
`
`throttle (which increases combustion rate and resultant temperatures) results in a
`
`higher pressure ratio (vrf) and mass flow rate ("'12‘l92/52 ), causing the fan to operate
`
`at a point along the operating line that is upward and to the right. A decrease in
`
`throttle (which decreases combustion rate and resultant temperatures) results in a
`
`lower pressure ratio and mass flow rate, causing the fan to operate at a point along
`
`UTC-2009.009
`
`
`
`the operating line that is downward and to the left. (GE-1014.078-) The lines that
`
`cut across the operating line (e.g., see below 110, 100, 90, 80, 65, etc.) are constant
`
`speed lines that provide the corrected rotational speed of the fan.
`
`-8
`N
`if 7!;
`*5
`§
`a..
`
`1.5
`Design point
`1'4 Operating line
`u
`Stall line
`
`
`
`1.3
`
`[.2
`
`40
`
`so
`so
`100
`% design n22~!0_2/62
`
`120
`
`'
`
`’
`
`40'
`
`'
`
`60
`80
`100
`% "design m2~!<9—2/62
`
`120
`
`Corrected Mass Flow Rate
`
`Efiect ofthrottle increase (left); Ejfect of throttle decrease (right)
`
`(GE—1014.088, Fig. 9-39 (color annotations added).)
`
`25.
`
`The design and geometry of the fan, the exit area of the fan bypass
`
`nozzle, and other features in the engine flow path affect and define the fan’s oper-
`
`ating line within the fan map. Modifying the geometry of the fan can cause the op-
`
`erating line to be located in more efficient regions of operation within the fan map.
`
`However, efficiency improvements are limited by boundaries where the fan can
`
`become unstable or engine performance can otherwise become undesirable. (’5l3
`
`9
`
`UTC-2009.010
`
`
`
`patent at 1:16-24, 3:30-37.) The ’513 patent discusses the “stall boundary,” which
`
`is when airflow across the fan is permanently separated, and the “flutter bounda-
`
`ry,” which is when the fan oscillates in unstable ways potentially leading to failure.
`
`(UTC-2008, 46:13-15.) Fan flutter, surge, and stall can all be dangerous to the fan,
`
`the engine, and the aircraft. The stall boundary is fixed for a given fan geometry,
`
`and designers typically design a fan’s geometry so that the fan’s operating line
`
`avoids crossing this boundary. Thus, fan maps are an important part of a turbofan
`
`engine designer’s work.
`
`26. The design of other features within the turbofan engine can also move
`
`the fan’s operating line. One of these design features is the exit area of the fan by-
`
`pass nozzle. (’513 patent at 3:24-37.) Most turbofan engines use fixed nozzles for
`
`the bypass duct. (’513 patent at 1:14-15) Using a fixed bypass nozzle with a larger
`
`exit area decreases the pressure downstream of the fan and increases the amount of
`
`air that can flow through the bypass passage, thereby causing the fan to operate on
`
`a line further away from the stall or flutter boundary. On the other hand, using a
`
`fixed nozzle with a smaller exit area increases the pressure downstream of the fan
`
`and decreases the amount of air that can flow through the bypass passage, causing
`
`the fan to operate on a line closer to the stall or flutter boundary.
`
`
`
`10
`
`UTC-2009.011
`
`
`
`Operating Imc 2i—’
`
`A.I
`I
`
`/‘F
`
`//
`
`l
`
`.
`
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`
`y
`
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`
`~
`
`/
`
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`
`/
`
`1.4 —
`
`,
`
`:32’
`Q) Hf
`I-n
`a
`2
`9..
`
`13 —
`
`12—
`
`Stall line .\
`
`"'
`
`,
`
`]_|
`
`I
`40
`
`I
`60
`
`I
`80
`
`I
`100
`
`I
`120
`
`.
`
`40
`
`so
`
`so
`
`100
`
`120
`
`% design I)1_~\IE/(53
`
`% design nz_~N'I9_»/I53
`
`Corrected Mass Flow Rate
`
`Eflect oflarger bypass exit area (left); Effect ofsmaller bypass exit area (right)
`
`(GE-1014-088, Fig- 9-39 (with modifications)_)
`
`27. Using a fixed nozzle requires engine designers to select an exit area
`
`that allows the fan to operate in all conditions but is potentially not ideal for any
`
`particular set of conditions. (’5l3 patent at 1:26-31.) This compromise is required
`
`at least in part because the operating line and stall or flutter boundary are typically
`
`non-parallel lines, and an operating line located too close to the stall or flutter
`
`boundary may result in the fan crossing the boundary, leading to potential stall or
`
`flutter problems. Thus, for fixed nozzle designs, the desire to use a smaller nozzle
`
`exit area for high pressure, high mass flow situations (e.g_, to increase efficiency
`
`during cruise) must be compromised by the need to avoid crossing the stall or flut-
`
`ter boundary in other situations (eg, to increase safety margin during takeoff and
`
`landing). (See, e.g_, ’5 13 patent at 1:24-31.)
`
`1 1
`
`UTC-2009.012
`
`
`
`Stall or Flutter
`
`Boundary
`
`PressureRatio
`
`
`Dark Blue Line Has
`Larger Operability
`Margin Than Light
`Blue Line
`
`‘
`
`Lmes
`
`Corrected Mass Flow Rate
`
`28- As illustrated in the figure above, the dark blue operating line is closer
`
`to the red stall or flutter boundary at lower mass flow rates and lower pressure rati-
`
`os, than it is at higher mass flow rates and higher pressure ratios. This means that
`
`the fan operability margin is less at the lower flow rates and pressure ratios than at
`
`the higher flow rates and pressure ratios. Similar observations apply to the light
`
`blue operating line, although the light blue operating line provides less fan opera-
`
`bility margin, with the operating line closely approaching the stall or flutter bound-
`
`ary at low pressure ratios and mass flow rates. For an engine with a fixed-geometry
`
`nozzle, the operating condition represented by the light blue line may represent the
`
`limiting condition, or “worst—case scenario” for the fan operability margin, which
`
`12
`
`UTC-2009.013
`
`
`
`cannot be permitted to cross the stall or flutter boundary. Conditions encountered
`
`during flight, such as inlet flow distortions and transients, can also cause the fan to
`
`temporarily deviate from its operating line. Given the undesirable effects of the fan
`
`crossing the fan stall or flutter boundary, designers build in an additional margin
`
`between the fan operating line and the stall or flutter boundary. (’513 patent at
`
`1:59-62, 3:24-37-) I provide below a figure that indicates the margin with green
`
`lines:
`
`Pressure
`
`Ratio
`
`Exemplary
`margin
`
`Stall or Flutter
`
`Boundary
`
`
`
`
`Exemplary
`margin
`
`Corrected Mass Flow Rate
`
`29.
`
`To overcome these and other issues, the ’513 patent defines a “target
`
`operability line,” which I will explain in more detail below. The ’5l3 patent uses a
`
`flow control device that “effectively chang[es]” the nozzle exit area to achieve the
`
`target operability line in response to airspeed and/or throttle position. (’513 patent
`
`1 3
`
`UTC-2009.014
`
`
`
`at 1:46-56.) The patent discloses a controller that commands the flow control de-
`
`vice. (’5l3 patent at 1:51-52.) Below is a figure showing the control arrangement:
`
`Controller
`
`34
`
`58
`
`52
`so
`'
`
`CWROLLER
`F
`Airspeed sensor
`£3.
`Flow control devi
`
`I
`/4
`
`CC
`
`)
`
`Throttle position
`sensor
`
`
`
`e
`“‘ /’
`
`
`
`(’513 patent at Fig. 2 (armotations added).)
`
`30-
`
`The flow control device can effectively change the nozzle exit area
`
`using structure (e.g., with hinged flaps) or by non—structural methods, such as alter-
`
`ing a boundary layer. (’5 13 patent at 2:54-65.) I include Figure 2 above, which de-
`
`picts the hinged-flap design- In the hinged-flap design, multiple hinged flaps 42 are
`
`arranged around the circumference of the bypass duct outlet. (’513 patent at 3:18-
`
`20.) Actuators 46 connect to the flaps and help pivot the flaps individually or in
`
`groups. (’5 13 patent at 3:20-23.) The actuators are connected to and controlled by a
`
`controller 50 to drive the flaps to a position that causes the engine to achieve the
`
`target operability line. (’5 13 patent at Fig- 2.)
`
`14
`
`UTC-2009.015
`
`
`
`31. A “target operability line” is a line connecting points across different
`
`fan operating lines that optimizes fan operability margin. The engine uses the flow
`
`control device to effectively change the nozzle exit area to achieve the “target op-
`
`erability line.” (’513 patent at 1:51-52.) The controller is programmed to command
`
`the flow control device for effectively changing the nozzle exit area to achieve the
`
`target operability line “in response to an engine operating condition . . . .” (’513 pa-
`
`tent at 4:14-17.)
`
`32. The ’513 patent gives examples of how the controller changes the
`
`nozzle exit area to achieve the “target operability line” across the flight envelope
`
`and different operating lines. Referring to Figure A below, during idle, for exam-
`
`ple, the controller can command an increase in the nozzle exit area so that the op-
`
`erating line (blue) matches the target operability line (green) for lower pressure ra-
`
`tio and mass flow conditions. (See ’513 patent at 3:51-54.) During cruise, which
`
`involves higher pressure ratios and mass flow rates, the controller can command
`
`the flow control device to match the target operability line for that operation condi-
`
`tion, as shown in Figure C below. (See ’513 patent at 3:57-58.). The controller can
`
`also command the flow control device to accommodate intermediate conditions, as
`
`shown in Figure B below. (See ’513 patent at 3:58-59).
`
`
`
`15
`
`UTC-2009.016
`
`
`
` Controlling
`
`operating lineto
`match target
`operability linefor
`lo_w pressu relflow
`
`PressureRatio
`
`Mass Flow Rate
`
`
`
`Controlling
`operating line to
`match target
`' operability linefor
`intennediate
`
`pressu refflow
`
`#7
`1
`
`
`
`Mass Flow Rate
`
`16
`
`UTC-2009.017
`
`PressureRatio
`
`
`
`PressureRatio
`
`Controlling
`operating lineto
`match target
`operability linefor
`h_’gfl pressu relfl ow
`
`Mass Flow Rate
`
`33.
`
`Thus, for any flight condition, the controller can dynamically adjust
`
`the flow control device to maintain the operation of the fan at the target operability
`
`line. (’513 patent at 3:54-55.) Achieving the target operability line allows the fan to
`
`operate closer to the stall or flutter boundary line across all operating conditions,
`
`and therefore, more efficiently. This will be effective for the range of conditions
`
`between the open and closed conditions of the variable nozzle-
`
`34.
`
`It is important to note that operating along a “target operability line”
`
`requires closing and opening the flow control device. (’513 patent at 3:30-33 (“A
`
`change in the effective nozzle exit area .
`
`.
`
`. is used to move the operating line to-
`
`ward the stall or flutter boundary of the turbofan 20 to a target operability line.”).)
`
`This is not a normal operating line, which a fan operates along due to throttle input
`
`alone.
`
`1 7
`
`UTC-2009.018
`
`
`
`35. The ’513 patent refers to “mov[ing]” the operating line by opening
`
`and closing the flow control device. (’513 patent at abstract (“A change in the noz-
`
`zle exit area . . . is used to move the operating line.”).) In this context, “moving”
`
`the operating line refers to passing from one operating line to another operating
`
`line.
`
`36. Because a “target operability line” includes points from many operat-
`
`ing lines, a target operability line cannot possibly lie along a single one of the fan’s
`
`operating lines. This is because opening or closing the nozzle exit area causes the
`
`fan to pass between operating lines. (’513 patent at abstract (“A change in the noz-
`
`zle exit area . . . is used to move the operating line.”).) Progressive closing of the
`
`flow control device causes the fan to continuously change to new operating lines.
`
`In other words, the target operability line intersects points from multiple operating
`
`lines, as I show in the Figure below:
`
`
`
`
`
`18
`
`UTC-2009.019
`
`
`
`Target Oper-
`ability Line
`
`
`
`Pressure
`
`Ratio
`
`,1
`
`Operating
`Lines
`
`
`
`Corrected Mass Flow Rate
`
`37.
`
`The flexibility created by a “target operability line” is beneficial be-
`
`cause it allows the line to have a shape that is unconstrained by the shape of the
`
`fan’s operating line(s). Thus, the “target operability line” can more closely hug the
`
`stall or flutter boundary, as depicted above, achieving efficient engine operation
`
`across all operating conditions. The ’513 patent explains, “[b]etter fuel consump-
`
`tion, for example, is achieved by decreasing the turbofan pressure ratio toward the
`
`stall or flutter boundary, which decreases the fan operability margin.” (’513 patent
`
`at 3:30-37.) By setting the “target operability line” based on the stall or flutter
`
`boundary, the controller can provide “desired fuel consumption, engine perfor-
`
`mance, and/or fan operability margin.” (’5 13 patent at 1:47-49.)
`
`19
`
`UTC-2009.020
`
`
`
`38. The ’513 controller achieves the “target operability line” in response
`
`to an “engine operating condition.” The engine operating condition can include “at
`
`least one of airspeed and throttle position.” (’513 patent, claim 1; see also 1:54-56
`
`(“The effective change in nozzle exit area achieves the target operability line in re-
`
`sponse to an engine operating condition that is a function of airspeed and throttle
`
`position.”).) The ’513 patent shows sensors connected to controller 50, including
`
`an airspeed sensor 52 and a throttle position sensor 58. (’513 patent at 3:42-43,
`
`3:44-46, Figure 2.)
`
`B. Claim Construction
`I have been informed that it would be useful to provide some guidance
`39.
`
`in this proceeding with respect to certain terms. As part of that, for each term ad-
`
`dressed below, I considered each term’s context within the claim, each term’s use
`
`within the specification, the prosecution history, and my understanding of how one
`
`of ordinary skill in the art would understand the term around the time of the inven-
`
`tion. I have been informed that I must construe the claims using the broadest rea-
`
`sonable interpretation consistent with the specification.
`
`
`
`20
`
`UTC-2009.021
`
`
`
`1.
`
`“Target Operability Line”
`
`A line connecting points
`across different fan oper-
`ating lines that optimizes
`fan operability margin-
`
`The series of points with-
`in a fan map that the fan
`section is designed to op-
`erate (i.e., an operating
`line). (Pet. 22.)
`
`sion 8.)
`
`A specific operating line
`that is defined by the se-
`ries of points on a fan
`map at which the fan sec-
`tion of a turbofan engine,
`or turbofan, is designed to
`operate. (Institution Deci-
`
`40.
`
`I explain the term “target operability line” by first explaining the well-
`
`known term “operating line.” The term “operating line” refers to a line on a fan
`
`map that defines the steady-state pressure ratio and corrected mass flow rate that a
`
`gas turbine engine’s fan will possess for a given fan speed. I have included an an-
`
`notated fan map below. It shows the operating line as the green dash—dot line.
`
`21
`
`UTC—2009.022
`
`
`
`Pressure Rf
`
`Ratio
`
`40
`
`60
`
`80
`
`100
`
`120
`
`% design trip/9-2/62
`
`Corrected Mass Flow Rate
`
`(GE-1014.088, Fig. 9-39 (color annotation added).)
`
`41- During flight, a fan typically operates at different points up and down
`
`a single operating line. (GE—1014.078.) An increase in throttle increases combus-
`
`tion rate in the engine and resultant temperatures. This in turn results in a higher
`
`pressure ratio and corrected mass flow rate, causing the fan to operate at a point
`
`along the operating line that is upward and to the right in the figure above. (See
`
`GE-1014.078.) A decrease in throttle decreases combustion rate and resultant
`
`temperatures, which in turn results in a lower pressure ratio and corrected mass
`
`flow rate, causing the fan to operate at a point along the operating line that is
`
`downward and to the left in the figure. (GE-1014.078.)
`
`22
`
`UTC-2009.023
`
`
`
`42. An “operating line” is inherent to every fan, and a person having ordi-
`
`nary skill in the art would understand its meaning. The ’513 patent describes and
`
`uses the term “operating line” consistent with the person of ordinary skill’s under-
`
`standing. The ’513 patent states that the “fan operating line is defined, for example,
`
`by characteristics including low spool speed, turbofan airflow and turbofan pres-
`
`sure ratio.” (’513 patent at 1:19-22.)
`
`43. The ’513 patent first teaches that “target operability line” and “operat-
`
`ing line” are distinct terms (and that “operating” and “operability” are different
`
`concepts). The ’513 patent distinguishes between these terms. For example, the
`
`’513 patent states (I added the emphasis in each instance):
`
`The change in nozzle exit area (40) achieves the target
`operability line in response to an engine operating condi-
`tion that is a function of airspeed and throttle position. A
`change in the nozzle exit area (40) is used to move the
`operating line toward a fan stall or flutter boundary by
`manipulating the fan pressure ratio. (’513 patent at Ab-
`stract.)
`
`The invention relates to a turbofan engine, and more par-
`ticularly, the invention relates to managing fan operabil-
`ity and operating characteristics. (’513 patent at 1:5-7.)
`
`
`
`
`23
`
`UTC-2009.024
`
`
`
`The fan operating line can be manipulated during engine
`operation to ensure that the fan operability margin is suf-
`ficient. (’513 patent at 1:17-19.)
`
`What is needed is a turbofan engine that provides im-
`proved operability for a variety of engine operating con-
`ditions while minimizing performance penalties through-
`out the flight envelope. (’513 patent at 1:37-40.)
`
`The effective change in nozzle exit area achieves the tar-
`get operability line in response to an engine operating
`condition that is a function of airspeed and operating
`condition. (’513 patent at 1:54-56.)
`
` A
`
` change in the effective nozzle exit area is used to move
`the operating line toward a turbofan stall or flutter
`boundary by manipulating the turbofan pressure ratio. As
`a result, engine operating conditions that normally have
`unnecessarily large operating margins with conventional
`fixed nozzles can be made more efficient. (’513 patent at
`1:56-62.)
`
` A
`
` change in the effective nozzle exit area, which changes
`the turbofan pressure ratio, is used to move the operating
`line toward the stall or flutter boundary of the turbofan to
`a target operability line. (’513 patent at 3:30-33.)
`
`
`
`24
`
`UTC-2009.025
`
`
`
`Based on these passages, in conjunction with the use of a term that differs from
`
`known terms in the art, it is my opinion that a person of ordinary skill in the art at
`
`the time of the ’513 invention would have understood that an “operating line” is
`
`distinct from a “target operability line.”
`
`44. Claims 1 and 4-8 all require a “target operability line.” It is a term
`
`unique to the ’513 patent, and the ’513 patent reveals its meaning. It is my opinion
`
`that one of ordinary skill in the art would have understood this claim term to mean,
`
`consistent with the specification, “a line connecting points across different fan op-
`
`erating lines that optimizes fan operability margin.”
`
`45. Before the ’513 patent introduces the “target operability line,” it ex-
`
`plains the importance of the “fan operability line” and its relationship to “fan oper-
`
`ability margin.” (’513 patent at 1:16-40.) It teaches that “[t]he engine is designed to
`
`meet the fan operability line and optimize the overall engine performance through-
`
`out the flight envelope.” (’513 patent at 1:25-27.) The fan operability line is de-
`
`fined by the fan operability margin that is required to avoid undesired fan condi-
`
`tions: “[t]he fan’s operating line must be controlled to avoid undesired conditions
`
`such as fan flutter, surge or stall . . . [and] can be manipulated during engine opera-
`
`tion to ensure that the fan operability margin is sufficient.” (’513 patent at 1:16-
`
`19.) Thus, a “desired fan operability margin” can be maintained “to avoid unde-
`
`sired conditions” by “chang[ing] the fan operating line.” (’513 patent at 1:22-24.)
`
`
`
`25
`
`UTC-2009.026
`
`
`
`This is consistent with the plain meaning of “operability” in this industry. For ex-
`
`ample, one resource in the field states that “[t]he goal of engine operability is to as-
`
`sure that the engine operates free of instability or with an acceptably small number
`
`of recoverable aerodynamic instabilities during the on-aircraft life of the engine.”
`
`(UTC- 2011, Aircraft Propulsion Systems Technology and Design 340 (Gordon C.
`
`Oates ed., 1989).)
`
`46. The ’513 patent’s invention introduces the concept of a “target” oper-
`
`ability line based upon the key concept that an optimized fan operability margin
`
`may be achieved by changing the fan operating line. As described in the ’513 pa-
`
`tent, conventional engines must compromise fuel consumption or engine perfor-
`
`mance to ensure adequate fan operability margin. (’513 patent at 1:27-36 (to meet
`
`fan operability margin requirements, “the engine design is compromised to ac-
`
`commodate various engine operating conditions that may occur during the flight
`
`envelope.”) This is because they are able to operate on only one operating line for
`
`a given set of flow conditions. In other words, they are not able to move from one
`
`operating line to another to improve their performance. Conventional engines
`
`therefore must be designed with margin that will be sufficient in the worst-case
`
`scenario in the flight envelope. This results in “performance penalties” due to “un-
`
`necessarily large operating margins.” (’513 patent at 1:34-36; 1:58-61, 3:28-30.)
`
`
`
`26
`
`UTC-2009.027
`
`
`
`47. The variable nozzle and control arrangement of the ’513 patent
`
`changes this model. It teaches establishing a “target” fan operability line seeking to
`
`avoid “unnecessarily large operating margins.” (’513 patent at 1:58-61, 3:28-30.)
`
`The target operability line thus “provides desired fuel consumption, engine per-
`
`formance and/or operability margin.” (’513 patent at 1:47-49; see also 3:34-37.) It
`
`does this by controlling a variable nozzle “to move the operating line toward the
`
`stall or flutter boundary . . . to a target operability line,” thereby “decreasing the
`
`turbofan pressure ratio toward the stall or flutter boundary, which decreases the
`
`fan operability margin.” (’513 patent at 3:30-37 (emphasis added).)
`
`48. An operating line does not literally “move” to a target operability line;
`
`rather, the fan passes from operating line to operating line. This is depicted below,
`
`where the fan moves across points on a series of operating lines. It is this series of
`
`points on different operating lines that make up the target operability line, and
`
`those points are specifically chosen to optimize the fan operability margin.
`
`
`
`27
`
`UTC-2009.028
`
`
`
`Target Opera-
`bility Line
`
`
`
`Pressure
`
`Ratio
`
`2,
`
`Operating
`Lines
`
`
`
`Corrected Mass Flow Rate
`
`49.
`
`This approach achieves the ’513 patent’s stated objective to provide
`
`“improved operability for a variety of engine operating conditions while 1ninirniz—
`
`ing performance penalties throughout the flight envelope.” (’5l3 patent at 1:37-
`
`40.) Accordingly, optimizing fan operability margin improves engine performance.
`
`(’5l3 patent at 1:25-27 (“[t]he engine is designed to meet the fan operability line
`
`and optimize the overall engine performance throughout the flight envelope.”).)
`
`50.
`
`The “target operability 1ine” therefore is “a line connecting points
`
`across different fan operating lines that optimizes fan operability margin.”
`
`51.
`
`I understand that the Board’s Institution Decision preliminarily con-
`
`strued “target operability line” as “a specific operating line that is defined by the
`
`28
`
`UTC-2009.029
`
`
`
`series of points on a fan map at which the fan section of a turbofan engine, or tur-
`
`bofan, is designed to operate.” (Institution Decision 8.) This is similar to Petition-
`
`er’s proposed construction, which defines target operability line as
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