JP2012508343A - Engine cleaning system and method - Google Patents

Abstract

A system for cleaning a gas turbine engine. The gas turbine engine has an intake portion and an exhaust portion, and the exhaust portion has an inner surface and an outer surface. The system includes a confinement structure that captures gaseous, liquid, and solid substances exiting the engine, a filtration system that separates gaseous, liquid, and solid substances, and a confinement structure that is secured to the exhaust. A retaining ring that is adjustable in size and / or shape to sealingly engage the inner surface of the exhaust. The confinement structure may comprise an expansion chamber. The system may further comprise a flexible boot connecting the confinement structure to the exhaust.
[Selection] Figure 1

Description

  The techniques described herein generally relate to gas turbine engines, and more particularly to systems and methods for cleaning a gas turbine engine and methods for determining a cleaning interval for a gas turbine engine.

  At least one known gas turbine engine assembly includes a fan assembly mounted upstream of the core gas turbine engine. In operation, a portion of the air flow exhausted from the fan assembly is directed downstream to the core gas turbine engine where the air flow is further compressed. The compressed air stream is then directed to a combustor, mixed with fuel, and ignited to produce hot combustion gases. The combustion gas is then directed to a turbine that extracts the energy that drives the compressor from the combustion gas and generates useful work to propel the aircraft in flight. The other part of the air flow exhausted from the fan assembly exits the engine through the fan flow nozzle.

  During operation, particularly when the aircraft is near the ground, such as during takeoff and landing operations, the gas turbine engine may inhale various forms of foreign matter such as dust, dirt, insects and the like. Such objects may be small enough to pass through without damaging the engine, or may be sufficiently brittle, but can leave residue on the internal surface of the engine. Combustion by-products passing through the engine, and oxidation of various components, can also generate residue and leave it on the internal surface of the engine. Over time, such residues can accumulate and adversely affect engine performance.

  Various systems and methods have been developed that "clean" or clean the interior surfaces of such gas turbine engines with a cleaning solution, thereby removing residue and restoring performance. However, many such systems have many components and / or large flexible structures that enclose the engine to be cleaned and are cumbersome to use. Many systems also fail to adequately capture the residue and post-use cleaning solution, resulting in loss of reusable solution and contamination of the external environment surface with the residue and cleaning solution.

  Accordingly, there remains a need for improved systems and methods for cleaning gas turbine engines that provide improved capture of residues and cleaning solutions.

  In addition, many operators of gas turbine engines rely on published recommendations based on operating conditions and elapsed operating time to determine when the engine needs to be cleaned. Others perform cleaning operations based on a certain operation cycle or a certain frequency. Still others rely on some change in engine performance levels. However, such a method of determining when cleaning is required can result in over- or under-performing cleaning operations for optimal performance.

  Accordingly, there remains a need for improved methods of determining when engine cleaning is required for optimal implementation.

  In one aspect, a system for cleaning a gas turbine engine is described, the gas turbine engine having a suction portion and an exhaust portion, the exhaust portion having an inner surface and an outer surface. The system includes a confinement structure that captures gaseous, liquid, and solid substances exiting the engine, a filtration system that separates gaseous, liquid, and solid substances, and a confinement structure that is secured to the exhaust. A retaining ring that is adjustable in size and / or shape to sealingly engage the inner surface of the exhaust.

  In another aspect, a method for cleaning a gas turbine engine is described, the method comprising preparing a gas turbine engine, the engine having an intake portion and an exhaust portion, the exhaust portion having an inner surface and an outer surface. Providing a system for cleaning a gas turbine engine, the system comprising a confinement structure, and removably securing the confinement structure to an inner surface via a retaining ring; A step of feeding the cleaning liquid into the intake section and a step of collecting the cleaning liquid within the confinement structure.

  In another aspect, a method for determining when to clean a gas turbine engine is described, the method comprising measuring gas turbine engine engine performance data, wherein the gas turbine engine is in a regional operating condition. fleet) and steps that are part of engine family operating fleet, calculating average performance data of area operating equipment, calculating average performance data of engine family operating equipment, and gas It is necessary to clean the gas turbine engine when comparing the performance data of the turbine engine with the average data of the area operating equipment and when the comparison shows that the performance of the gas turbine engine has deteriorated. Showing a sex.

  In another aspect, a method is described for determining an appropriate cleaning interval for cleaning a gas turbine engine, the method comprising measuring gas turbine engine engine performance data, wherein the gas turbine engine is a regional operational equipment. And calculating the key engine performance characteristics of a gas turbine engine from measurement data and engine manufacturer development and testing throughout the gas turbine engine life cycle, Calculating the average rate of equipment change in key performance characteristics derived from the engine manufacturer's algorithms and modeling for uncleaned and cleaned engines, the key performance characteristics of the gas turbine engine derived by the engine manufacturer, and , Equipment data and Calculating the average duration of cleaning effects based on the rate of change of these key performance characteristics based on operational requirements, collecting average section fuel combustion data for specific area operational equipment, maintenance costs and Calculating other cost of ownership affected by engine cleaning, including impact on overhaul intervals, collecting fuel costs and engine cleaning cost data for specific area operating equipment, and each specific aircraft Calculating an optimal cleaning interval based on an economic cost-benefit analysis for a particular area operating equipment, personalized for the company.

1 is a side view of an exemplary gas turbine engine and engine cleaning system. FIG. FIG. 2 is a top view of the gas turbine engine and engine cleaning system shown in FIG. 1. FIG. 3 is an elevational cross-sectional view of the engine cleaning system shown in FIG. 1 along line 3-3 showing the primary mist collection device. FIG. 4 is an exploded view of a mist collector suitable for use in the engine cleaning system shown in FIGS.

  FIG. 1 is a side view of an exemplary gas turbine engine assembly 10 having a longitudinal axis. The gas turbine engine assembly 10 includes a fan assembly and a core gas turbine engine. The core gas turbine engine includes a high pressure compressor, a combustor, and a high pressure turbine. In the exemplary embodiment, gas turbine engine assembly 10 also includes a low pressure turbine, a multi-stage booster compressor, and a splitter substantially surrounding the booster.

  The fan assembly includes a series of fan blades that extend radially outward from the rotor disk. The gas turbine engine assembly 10 has an intake surface and an exhaust surface. The fan assembly, the booster, and the turbine are integrally coupled by a first rotor shaft, and the compressor and the turbine are integrally coupled by a second rotor shaft.

  In operation, air flows through the fan assembly and a first portion of the air flow is directed through the booster. The compressed air discharged from the booster is directed through a compressor that further compresses the air flow and is discharged to the combustor. Hot combustion products from the combustor are used to drive the turbine, and one turbine is used to drive the fan assembly and booster via the shaft. The first part of the air flow is discharged to the atmosphere through the nozzle 15 along with the combustion products. The gas turbine engine assembly 10 is operable in an operating state region between a designed operating state and an off-design operating state.

  A second portion of the air flow exhausted from the fan assembly is directed through a bypass duct that bypasses a portion of the air flow from the fan assembly around the core gas turbine engine. More specifically, the bypass duct extends between the fan casing or shroud and the splitter. Thus, the first portion of the air flow from the fan assembly is then routed through the booster and then to the compressor, as described above, and the second portion of the air flow from the fan assembly is directed through the bypass duct. For example, thrust is generated for an aircraft. The gas turbine engine assembly 10 also includes a fan frame assembly that provides structural support for the fan assembly and is also used to couple the fan assembly to the core gas turbine engine.

  Also shown in FIG. 1 is an engine wash system 20. The engine cleaning system 20, shown in the form of an exemplary water wash trailer (WWT) unit, includes a trailer 30 or other suitable vehicle, a flexible boot 40, an annular clamp 45, and a droplet receiver. A capture device 50, a collection system 60, an optional storage cabinet 70, and a cleaning liquid ejection system (not shown), which may be a commercially available system.

  The engine cleaning system 20 is designed to collect waste water and engine exhaust particles from the exhaust nozzle 15 while performing an engine cleaning operation with the gas turbine engine assembly 10 mounted on an aircraft. Emerging from a gas turbine engine is typically a combination of gaseous, liquid, and solid materials, such as air, water or cleaning solutions, and particulate materials.

  The flexible boot 40 is mounted inside the exhaust nozzle 15 via a retaining ring in the form of an annular clamp 45, which is an internal annular clamp specially designed for this purpose. It is dimensioned and configured to engage with the inner surface. That is, the annular clamp 45 can secure the flexible boot to the exhaust nozzle without the need for additional metal products or specially designed mechanisms on the gas turbine engine assembly 10. In order to secure the boot 40 to the nozzle 15, the annular clamp 45 is reduced in size to a diameter smaller than the diameter of the exhaust nozzle 15 and is sufficient in the nozzle 15, eg about 3 inches from the outlet of the exhaust nozzle 15. It is inserted only a certain distance. The annular clamp 45 is then expanded by any suitable mechanism, such as the hand crank screw shown in the embodiment of FIG. 1, to move the flexible boot 40 and the inner surface of the nozzle 15 along their circumference. Make sure to make contact. This engagement ensures a positive sealing engagement that helps to ensure a high capture rate for the exhaust air exiting the nozzle 15. An annular clamp or retaining ring may be variable in shape in addition to or instead of being dimensioned so that it can be inserted into the exhaust nozzle and then engaged with the inner surface of the nozzle.

  The collection system 60 has mechanisms that help to capture and collect cleaning fluid and material removed from the gas turbine engine assembly 10. 1-3, the collection system 60 includes a water collection transition plenum 62 that serves as an expansion chamber that decelerates the air and droplets exiting the nozzle 15, and primary and secondary mist collection devices 64 and 66. Both are provided. The primary mist collector 64 is designed to intercept water or fluid mist from the exhaust air, and the secondary mist collector 66 captures any mist and droplets that pass through the primary mist collector 64. Designed to capture. FIG. 3 shows in more detail one structure suitable for use as the mist collector 64 and / or 66, although a wide variety of other structures may be suitable. The mist collecting device may have a single layer structure or a multilayer structure as shown in FIG.

  The physical details of the engine cleaning system 20, including the dimensions and shapes of various elements, can be adapted for use with one or more specific configurations of the gas turbine engine assembly 10. Furthermore, the cleaning fluid can be selected for specific cleaning characteristics and atmospheric environments such as temperature. Under some circumstances, normal water from public or other water sources can be used, and in other environments, a mixture of water and a cleaning agent such as a detergent can be used. In the cold state, a mixture of water and alcohol can be used for engine cleaning operations. If desired, the cleaning fluid may be warmed.

  The engine cleaning system 20 may be a fully self-contained unit that both inputs and collects cleaning fluids, such as those currently commercially available that are separately equipped and / or operated. It may also be a collection unit that relies on a cleaning fluid input system. A collection-type unit typically includes a suction pump that removes the collected liquid from the collection system, a filter that removes particulate matter and / or wash solution from the water, and the amount used in normal engine wash procedures. And a storage tank of sufficient capacity, for example 60 gallons. A fully self-contained unit comprises supply and input equipment, including a heater or other pretreatment equipment, and the collection mechanism described above.

  Other optional mechanisms that may be provided include a detergent filtration system, a cold water storage tank, a hot water tank with a heater, a detergent tank, a high-pressure pump for spraying, and a water tank or detergent tank A manual selection valve, a pressure relief valve, and a solution injection tube (often in the form of a shepherd's wand).

  A transition plenum 62 made of a suitable material such as stainless steel captures moisture mist from the exhaust nozzle 15 and collects spent wash water or fluid. The plenum is designed so that the air discharged from the nozzle 15 enters the plenum and expands and slows down, thereby increasing the likelihood of trapping moisture mist and particles. The plenum and / or collection system may include vanes that deflect and / or slow the air flow to facilitate liquid separation. The waste water is drained and falls into the drop receiver 50, where the one or more drop receivers 50 are free from any traces of wash water that may leak from the gas turbine engine assembly 10 or various elements of the engine cleaning system 20. Or it works to capture and collect fluids.

  A pump, such as a self-priming pump, can be used to transfer used wash water or fluid, optionally through a water filtration system, into the storage tank. Appropriate filters may be provided to filter used wash water or fluid to a desired standard, including removing particulate material of a specified size, such as 1 micron. One or more appropriately sized water tanks may be provided for storing filtered water for further use or later disposal.

  Trailer 30 is equipped with a convenient mechanism for supporting, storing, and organizing the various elements of engine cleaning system 20. An elevating mechanism (not shown) can optionally be provided as part of engine cleaning system 20 and / or trailer 30. Such a lifting mechanism can be used to position the elements of the engine wash system 20 at a desired height for use in various configurations of aircraft and gas turbine assemblies. Such a lifting mechanism may be an integral part of the engine cleaning system 20, or may be a separate vehicle or mechanism, and may include a hydraulic pump, an electric motor, and associated manifolds, valves, lines, and check valves, or May be mechanically operated and supported. A suitable lifting mechanism is designed and configured to support the elements of the engine cleaning system 20 and may include safety mechanisms such as locks, struts, etc. that ensure safe operation. A lifting mechanism, or other mechanical, pneumatic, or hydraulic mechanism may be provided to adjust the alignment of the plenums, boots, or other elements of the system, such as hand cranks or other methods. Can be operated manually or driven by an electric motor or other device.

  Other elements that may be included in or used in conjunction with the engine cleaning system 20 include a generator that powers the system, a vacuum cleaner that vacuums and collects any residual water from the exhaust nozzle, or other Included are such seed suction generating devices, and a ground wire that connects to an appropriate electrical grounding device at the operating position.

  In preparation for the work, the water washing procedure from the aircraft operations manual and / or aircraft maintenance manual should be consulted for each type of aircraft that is to carry out the engine washing procedure. One important requirement is that the gas turbine engine should be operated in “dry motoring” mode, and the core components of the gas turbine engine must be engineed without supplying any fuel to the fuel system (such as a fuel nozzle). It is to be rotated by a starter. This is the same as “dry motoring”, but with “wet motoring” that supplies fuel to the fuel system, and for the gas turbine to start and maintain its own power, usually on the ground In contrast to “ground idle”, which operates at the lowest idle speed.

  Prior to operating the engine wash system, the following steps are recommended. Inspect for damage during transport, remove cover and store, check for damage or abnormal events again, open door to storage and ensure generator tank is full, hydraulic Check for system leaks and make sure that the cylinder is in the correct position and the switch is disconnected. On the other hand, the aircraft operator will have the gas turbine engine run at ground idle for about 5 minutes or in other manners recommended by the aircraft maintenance manual, the engine will be stopped, and the engine cleaning system trailer will be connected to the engine centerline. And manually approach the engine until the plenum inlet is about 3 feet away from the nozzle outlet. Make sure the engine and plenum centerlines are coincident and slowly approach the trailer until the plenum inlet is approximately 20 inches away from the nozzle exit face. The flexible boot can then be secured to the engine exhaust nozzle via the retainer ring and the rest of the wash sequence can be performed.

  In order to maximize the benefits of a gas turbine engine water wash program, the wash process should be carried out at a time and at a time interval that will improve the desired performance while balancing the cost and time of the wash process itself. It is.

  The following method can be used to determine when and when to perform the engine cleaning operation for a given gas turbine engine at the appropriate time and at the appropriate time interval. The method comprises the steps of measuring the engine performance of a gas turbine engine, wherein the gas turbine engine belongs to the regional operating equipment and the engine family operating equipment, and calculating the average performance data of the regional operating equipment. And the step of calculating the average performance data of the engine family operating equipment, the step of comparing the engine performance data of the gas turbine engine with the average data of the area operating equipment, and the comparison step reduces the performance of the gas turbine engine. Indicating the need to clean the gas turbine engine.

  This overall method of determining when to clean can be further improved by more detailed methods such as those described below.

  Such a more detailed method of determining an appropriate time to perform an engine cleaning operation for a given gas turbine engine and an appropriate time interval includes the following steps. That is, measuring the engine performance data of a gas turbine engine, where the gas turbine engine is part of the regional and engine family operating equipment, and the measurement data and engine manufacturing throughout the engine life cycle. Calculate key engine performance characteristics from vendor development and testing and, for unwashed and washed engines, calculate the average rate of equipment change in key performance characteristics derived from engine manufacturer algorithms and modeling Calculating the average duration of cleaning effects based on the key performance characteristics derived by the engine manufacturer and the rate of change of those key performance characteristics based on equipment data and operational requirements; Average section fuel combustion volume data for regional operating equipment Collecting and calculating other cost of ownership affected by engine cleaning, including maintenance costs and impact on overhaul intervals, and collecting fuel costs and engine cleaning cost data for specific area operating equipment And calculating an optimal cleaning interval based on an economic cost-benefit analysis for a specific area operating equipment, personalized for each specific airline company.

  These methods can be improved as desired by further considering flight characteristics such as aircraft type, engine type, flight duration and distance. For example, such calculations may be performed using only data relating to a single aircraft type, a single engine type, or equipment or partial equipment having the same flight duration and / or distance.

  The engine wash system containment structure and other elements may be manufactured from any suitable material using any suitable manufacturing method known in the art suitable for the intended configuration and operating environment. Similarly, any suitable liquid can be used as the cleaning fluid, including water, detergents, and / or various solvents. The dimensions, shape, and arrangement of the various elements of the system can be adapted to suit any particular application or any particular requirement such as storage location, transportability, etc.

  While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.

DESCRIPTION OF SYMBOLS 10 Gas turbine engine assembly 15 Exhaust nozzle 20 Engine washing system 30 Trailer 40 Flexible boot 45 Annular clamp 50 Capture device, droplet receiver 60 Collection system 62 Water collection transition plenum 64 Primary mist collection device 66 Secondary mist collection device Collector 70 Storage cabinet

Claims (20)

A system for cleaning a gas turbine engine, wherein the gas turbine engine has an intake portion and an exhaust portion, and the exhaust portion has an inner surface and an outer surface,
A confinement structure that captures gaseous, liquid, and solid matter exiting the engine;
A filtration system for separating the gaseous, liquid, and solid substances;
A holding ring for fixing the confinement structure to the exhaust part,
A system in which at least one of size and shape is adjustable such that the retaining ring is sealingly engaged with the inner surface of the exhaust. The system of claim 1, wherein the confinement structure comprises an expansion chamber. The system of claim 1, further comprising a flexible boot connecting the confinement structure to the exhaust. The system of claim 1, wherein the exhaust is an exhaust nozzle. The system of claim 1 mounted on a trailer. The system of claim 1, comprising a flexible apron that traps liquid under the gas turbine engine. The system of claim 1, comprising a droplet receiver for capturing liquid. The system according to claim 1, comprising a primary mist collecting device and a secondary mist collecting device. The system of claim 1, wherein the retaining ring is an annular clamp. A system for cleaning a gas turbine engine, wherein the gas turbine engine has a suction portion and an exhaust nozzle, and the exhaust nozzle has an inner surface and an outer surface,
A confinement structure that captures gaseous, liquid, and solid matter exiting the engine;
A flexible boot connecting the confinement structure to the exhaust nozzle;
A filtration system for separating the gaseous, liquid, and solid substances;
A retaining ring for fixing the confinement structure to the exhaust nozzle,
A system in which at least one of size and shape is adjustable so that the retaining ring sealingly engages the inner surface of the exhaust nozzle. A method for cleaning a gas turbine engine, comprising:
Providing a gas turbine engine, wherein the engine has an intake portion and an exhaust portion, and the exhaust portion has an inner surface and an outer surface;
Providing a system for cleaning a gas turbine engine, the system comprising a confinement structure;
Removably securing the confinement structure to the inner surface via a retaining ring;
Feeding a cleaning liquid into the intake section;
Collecting the cleaning liquid within the confinement structure. The method of claim 11, wherein the confinement structure comprises an expansion chamber. The method of claim 11, further comprising a flexible boot coupling the confinement structure to the exhaust. A method for cleaning a gas turbine engine, comprising:
Providing a gas turbine engine, the engine having an intake and an exhaust nozzle, the exhaust nozzle having an inner surface and an outer surface;
Providing a system for cleaning a gas turbine engine, the system comprising a containment structure having an expansion chamber;
Removably securing the confinement structure to the inner surface via a flexible boot secured by a retaining ring;
Feeding a cleaning liquid into the intake section;
Collecting the cleaning liquid within the confinement structure. A method for determining when to clean a gas turbine engine, comprising:
Measuring engine performance data of a gas turbine engine, wherein the gas turbine engine is part of a zone operating equipment and an engine family operating equipment; and
Calculating average performance data of the area operational equipment;
Calculating average performance data of the engine family operating equipment;
Comparing the engine performance data of the gas turbine engine with the average data of the area operational equipment;
Indicating the need to clean the gas turbine engine when the comparing step reveals a degradation in performance of the gas turbine engine. The method of claim 15, wherein the data relates to a single gas turbine engine type. The method of claim 15, wherein the zone operating equipment and the engine family operating equipment comprise a single type of aircraft. A method for determining an appropriate cleaning interval for cleaning a gas turbine engine comprising:
Measuring engine performance data of a gas turbine engine, wherein the gas turbine engine is part of a zone operating equipment and an engine family operating equipment; and
Calculating key engine performance characteristics of the gas turbine engine from measurement data and engine manufacturer development and testing throughout the life cycle of the gas turbine engine;
Calculating the average rate of change of equipment for key performance characteristics derived from engine manufacturer's algorithms and modeling for unwashed and washed engines;
Calculating an average duration of cleaning effect based on the main performance characteristics of the gas turbine engine derived by the engine manufacturer and the rate of change of those main performance characteristics based on equipment data and operational requirements;
Collecting average section fuel combustion amount data of the specific area operational equipment;
Calculating other cost of ownership affected by engine cleaning, including maintenance costs and impact on overhaul intervals;
Collecting fuel cost and engine wash cost data for said specific area operational equipment;
Calculating an optimal cleaning interval based on an economic cost-benefit analysis for the specific area operating equipment, individualized for each specific aircraft company. The method of claim 18, wherein the data relates to a single gas turbine engine type. The method of claim 18, wherein the zone operating equipment and the engine family operating equipment comprise a single type of aircraft.