DK181051B1 - Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas - Google Patents
Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas Download PDFInfo
- Publication number
- DK181051B1 DK181051B1 DKPA202100342A DKPA202100342A DK181051B1 DK 181051 B1 DK181051 B1 DK 181051B1 DK PA202100342 A DKPA202100342 A DK PA202100342A DK PA202100342 A DKPA202100342 A DK PA202100342A DK 181051 B1 DK181051 B1 DK 181051B1
- Authority
- DK
- Denmark
- Prior art keywords
- engine
- gas
- exhaust
- pressure
- consumer
- Prior art date
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
- F02B37/12—Control of the pumps
- F02B37/16—Control of the pumps by bypassing charging air
- F02B37/164—Control of the pumps by bypassing charging air the bypassed air being used in an auxiliary apparatus, e.g. in an air turbine
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B25/00—Engines characterised by using fresh charge for scavenging cylinders
- F02B25/02—Engines characterised by using fresh charge for scavenging cylinders using unidirectional scavenging
- F02B25/04—Engines having ports both in cylinder head and in cylinder wall near bottom of piston stroke
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
- F02B37/12—Control of the pumps
- F02B37/18—Control of the pumps by bypassing exhaust from the inlet to the outlet of turbine or to the atmosphere
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
- B63B1/32—Other means for varying the inherent hydrodynamic characteristics of hulls
- B63B1/34—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction
- B63B1/38—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using air bubbles or air layers gas filled volumes
- B63B2001/385—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using air bubbles or air layers gas filled volumes using exhaust gas
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Supercharger (AREA)
Abstract
A large turbocharged two-stroke internal combustion engine (100) of the uniflow type configured to supply pressurized scavenging gas and/or exhaust gas to a consumer of pressurized gas (200) and a method for operating such an engine (100).
Description
. DK 181051 B1 METHOD AND LARGE TURBOCHARGED TWO-STROKE INTERNAL
TECHNICAL FIELD The present disclosure relates a method and large turbocharged two-stroke internal combustion engine configured to produce pressurized gas for use in another application in addition to mechanical energy for e.g. propulsion or driving an electric generator and to a method of operating such an engine.
BACKGROUND Large turbocharged two-stroke self-igniting internal combustion engines are typically used in propulsion systems of large ships or as a prime mover in power plants. Their sheer size, weight, and power output render them completely different from common combustion engines and place large two-stroke turbocharged compression-ignited internal combustion engines in a class for themselves. The height of these engines is typically not crucial, and therefore they are constructed with crossheads in order to avoid lateral loads on the pistons. Typically, these engines are operated with natural gas, petroleum gas, methanol, ethane, or fuel oil.
Large turbocharged two-stroke self-igniting internal combustion engines for ship propulsion (marine engines) are tuned in order to support certain fuel-efficient system installations onboard a vessel. In particular, waste heat recovery systems are relevant for the reduction of overall energy consumption and reducing emissions from the marine engine.
, DK 181051 B1 In certain applications, the engine is required to provide pressurized gas, e.g. pressurized air, pressurized exhaust gas, or a mixture of pressurized air and exhaust gas, in addition to providing mechanical energy for e.g.
propulsion. One such application is air lubrication. Marine vessels with a large flat bottom area can take advantage of reducing the resistance when moving through the water by air lubrication, and thereby the needed main engine power to propel the vessel at a given speed. The air lubrication system pumps a steady flow of air bubbles beneath the ship/s hull to lubricate the flat bottom area of the ship’s hull. To achieve the desired reduction in the power needed for ship propulsion, delivery of sufficient air/gas amount at sufficient pressure according to the vessel/s draft to the dedicated air-bubble generator interface is needed. Large two-stroke engines with standard tuning are often limited to provide sufficient pressurized air/gas at all required engine loads. JP2010228679A discloses an engine with standard tuning according to the preamble of claim 1.
SUMMARY It is an object of the invention to provide a large turbocharged two-stroke internal combustion engine of the uniflow type that overcomes or at least reduces the problems indicated above.
In order to avoid or at least reduce costly air compressor unit installation and operation, an adapted two-stroke engine is proposed.
> DK 181051 B1 The foregoing and other objects are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description, and the figures.
According to a first aspect, there is provided a large turbocharged two-stroke internal combustion engine of the uniflow type, according to claim 1 By providing a pressure sensor for sensing the scavenging air pressure or temperature sensor for sensing the temperature of the exhaust gas, and a controller configured to regulate the amount of pressure gas that is bypassed for supplying to the consumer of pressurized gas, it becomes possible to maximize the amount of pressurized gas produced by the engine for the consumer of pressurized gas, without risking the engine running at sub-optimal conditions. Considering that the bypass gas taken from the engine cycle leads inherently to an increase of the engine’s fuel consumption, the business case potential of a marine vessel with air lubrication is considerably enhanced by the engine according to the first aspect. Further, by tuning the engine to provide the highest possible scavenging pressure or the highest possible exhaust gas pressure, the engine can be transformed into a supplier of pressurized gas for delivery to an external consumer of pressurized gas, such as an air lubrication system of a marine vessel, which is much more effective compared to the use of e.g. air compressors driven by an electric drive motor.
In a first possible implementation form of the first aspect, the controller is configured to limit the amount of bypassed pressurized gas supplied to the consumer when the sensed scavenging pressure is below a scavenging
2 DK 181051 B1 pressure threshold and/or the sensed exhaust gas temperature is above an exhaust gas temperature threshold. In a further possible implementation form of the first aspect, the controller is configured to determine actual engine turbocharging effectiveness as a function of the sensed scavenging gas pressure and/or the sensed exhaust gas temperature. The term “engine turbocharging effectiveness” refers to the turbocharging effectiveness as experienced/felt by the engine, independent of ambient conditions. In a further possible implementation form of the first aspect, the controller is configured to limit the amount of bypassed pressurized gas supplied to the consumer as a function of the determined actual engine turbocharging effectiveness. In a further possible implementation form of the first aspect, the controller is configured to determine the actual available effectiveness excess of the one or more turbochargers compared to a predetermined minimum engine turbocharging effectiveness threshold.
In a further possible implementation form of the first aspect, the controller is configured to limit the amount of bypassed pressurized gas supplied to the consumer as a function of the determined available effectiveness of the one or more turbochargers.
In a further possible implementation form of the first aspect, the control unit is configured to adjust the amount of bypassed pressurized gas supplied to the consumer to the need for pressurized gas of the consumer of pressurized
- DK 181051 B1 gas, preferably, in response to a signal from the consumer of pressurized gas, preferably while avoiding exceeding thresholds.
In a further possible implementation form of the first aspect, the one or more turbocharges have, at least in a given engine load range, a turbocharger effectiveness that exceeds a predetermined minimum required engine turbocharging effectiveness.
In a further possible implementation form of the first aspect, the one or more turbochargers have a turbine with a variable geometry turbine allowing adjustment of the turbine flow area, the control unit being coupled to the one or more turbocharges for controlling the variable geometry of the turbine and the control unit being configured to adjust the geometry of the turbine to maximize the pressure delivered by the compressor under the actual the operating conditions of the engine, preferably by reducing the turbine flow area. In a further possible implementation form of the first aspect, the engine comprises two or more turbochargers, wherein the control unit is configured to cut-out one or more of the two or more the turbochargers, to maximize the pressure delivered by the compressor 7 under partial load conditions of the engine, the control unit being preferably configured to cut-out one or more of the two or more turbochargers as a function of the engine load.
In a further possible implementation form of the first aspect, a switch point for cutting out one or more of the two or more turbochargers is placed in the range of 60 to 80 % engine load, and the controller is configured to cut
. DK 181051 B1 out one or more of the two or more turbochargers 5 when the engine load is below the switch point. Additional turbocharges can be added similarly.
In a further possible implementation form of the first aspect, the engine comprises more than two turbochargers 5 and the controller 50 is configured to activate one turbocharge 5 below a first cutout engine load threshold, to activate two turbochargers 5 in an interval between the first cutout engine load threshold and a second cutout engine load threshold, and to activate three turbochargers 5 above the second cutout engine load threshold. In a further possible implementation form of the first aspect, the controller is operably coupled to a first electronic control valve for controlling the amount of scavenging gas taken from the intake system and/or operably coupled to a second electronic control valve for controlling the amount of exhaust gas taken from the exhaust system. In a further possible implementation form of the first aspect, partial engine load covers a range from 20 to 80% of the maximum continuous rating of the engine.
In a further possible implementation form of the first aspect, the controller is configured to operate the engine in a way to maximize scavenging gas pressure and/or exhaust gas pressure and/or maximize scavenging gas bypass mass- flow by one or more of: - increasing a power take in of one or more turbochagers provided with a turbo hydraulic system installation, -continuously running an auxiliary blower in the intake system of the engine,
; DK 181051 B1 - continuously running an EGR blower in an EGR installation of the engine, - activating an additional small turbocharger installation of the engine,
- opening an exhaust gas bypass to a power turbine installation of the engine for driving a dedicated electrically driven compressor,
- opening a cylinder bypass valve in a cylinder bypass installation of the engine, - activating a hydraulically driven compressor powered by a hydraulic pressure system installation of the engine.
In a further possible implementation form of the first aspect, the controller is configured to reduce the amount of bypassed pressurized gas supplied to the consumer when the sensed scavenging gas pressure is below a scavenging gas pressure threshold, the scavenge gas pressure threshold preferably being adjusted according to ambient conditions.
In a further possible implementation form of the first aspect, the controller is configured to reduce the amount of bypassed pressurized gas supplied to the consumer when the sensed exhaust gas temperature is above an exhaust gas temperature threshold, the exhaust gas temperature threshold preferably being adjusted according to ambient conditions.
In a further possible implementation form of the first aspect, partial engine load covers a range from 20 to 800% of the maximum continuous rating of the engine inventors is this a correct indication of the range, in particular in connection with turbocharger cutout, should the upper range.
Lower or higher
. DK 181051 B1
According to a second aspect, there is provided a method of operating a large turbocharged two-stroke internal combustion engine of the uniflow type, for supplying pressurized scavenging gas and/or exhaust gas from the engine to a consumer of pressurized gas, the engine comprising:
a plurality of cylinders with scavenge ports at their lower end and an exhaust valve at their upper end,
an intake system through which scavenging gas is introduced into the cylinders, the intake system comprising a scavenge gas receiver connected to the cylinders via the scavenge ports,
an exhaust system through which exhaust gas produced in the cylinders is exhausted, the exhaust system comprising an exhaust gas receiver connected to the cylinders via the exhaust valves,
at least one turbocharger having an exhaust gas-driven turbine operably coupled to a compressor, with an inlet of the turbine connected to the exhaust system and an outlet of the compressor connected to the intake system for delivering a flow of pressurized scavenge gas to the intake system,
the method comprising a bypass system for supplying bypassed pressurized gas to the consumer of pressurized gas,
bypassing a controlled amount of scavenging gas from the intake system or a controlled amount of pressurized exhaust gas from the exhaust,
sensing the scavenging gas pressure in the intake system and/or sensing the exhaust gas temperature in the exhaust system, and adjusting the amount of bypassed pressurized gas supplied to the consumer as a function of the sensed scavenging gas pressure and/or exhaust gas temperature.
; DK 181051 B1 These and other aspects of the invention will be apparent from and the embodiments described below.
BRIEF DESCRIPTION OF THE DRAWINGS In the following detailed portion of the present disclosure, the invention will be explained in more detail with reference to the example embodiments shown in the drawings, in which: Fig. 1 is an elevated front view of a large two-stroke internal combustion engine according to an example embodiment. Fig. 2 is an elevated side view of the large two-stroke internal combustion engine of Fig. 1. Fig. 3 is a diagrammatic representation of the large two- stroke internal combustion engine according to Fig. 1. Fig. 4 is a diagrammatic representation of an embodiment of the large two-stroke internal combustion engine with a plurality of turbochargers configured for turbocharger cut- out, and Fig. 5 is a diagrammatic representation of an embodiment of the large two-stroke internal combustion engine with a variable geometry turbocharger.
DETAILED DESCRIPTION Figs. 1, 2, and 3 show a large low-speed turbocharged two- stroke diesel engine 100 with a crankshaft 8 and crossheads
9. Fig. 3 shows a diagrammatic representation of a large low-speed turbocharged two-stroke diesel engine with its intake and exhaust systems. In this example embodiment, the engine 100 has six cylinders 1 in line. Large low-speed turbocharged two-stroke diesel engines have typically between four and fourteen cylinders 1 in line, carried by i DK 181051 B1 a cylinder frame 23 that is carried by an engine frame 11. The engine 100 may e.g. be used as the main engine in a marine vessel or as a stationary engine for operating a generator in a power station.
The total output of the engine 100 may, for example, range from 1,000 to 110,000 kW.
The engine 100 is in this example embodiment a compression- ignited engine 100 of the two-stroke uniflow type with scavenging ports 18 at the lower region of the cylinder liners 1 and a central exhaust valve 4 at the top of each cylinder liner 1. However, it is understood that the engine 100 does not need to be compression ignited but can alternatively be spark ignited.
Hence, in the present embodiment, the compression pressure of the engine 100 will be sufficiently high for compression ignition, but it is understood that the engine 100 can operate with lower compression pressure and ignited by spark or similar means.
The intake system of the engine 100 comprises a scavenge air receiver 2. The scavenge air is passed from the scavenge air receiver 2 to the scavenge ports 18 of the individual cylinders 1. A piston 10 that reciprocates in the cylinder liner 1 between the bottom dead center (BDC) and top dead center (TDC) compresses the scavenge air.
Fuel is injected through fuel valves 50 that are arranged in the cylinder cover 22. Combustion follows, and exhaust gas is generated.
An exhaust valve 4 is centrally arranged in the cylinder cover 22 with a plurality of fuel valves 55 is distributed around the central exhaust valve 4. The exhaust valve 4 is actuated by an electrohydraulic exhaust valve actuation system (not shown) that is controlled by a controller 50. The fuel valves 55 are part of the fuel supply system.
The
DK 181051 B1 controller 50 is also configured to control the operation of the fuel valves 55. When an exhaust valve 4 is opened, the exhaust gas flows through an exhaust system that includes an exhaust duct associated with the cylinders 1 into the exhaust gas receiver 3 and onwards through a first exhaust conduit 19 to a turbine 8 of a turbocharger 5 (in an embodiment, the engine 100 is provided with a plurality of turbochargers), from which the exhaust gas flows away through a second exhaust conduit via an economizer 20 to an outlet 21 and into the atmosphere. Through a shaft, the turbine 8 drives a compressor 7 supplied with fresh air via an air inlet 12. The compressor 7 delivers pressurized scavenge air to a scavenge air conduit 13 leading to the scavenge air receiver 2. The scavenge air in the scavenge air conduit 13 passes an intercooler 14 for cooling the scavenge air.
The cooled scavenge air passes via an auxiliary blower 16 driven by an electric motor 17 that pressurizes the scavenge air flow when the compressor 7 of the turbocharger 5 does not deliver sufficient pressure for the scavenge air receiver 2, i.e. in low or partial load conditions of the engine 100. At higher engine loads the turbocharger compressor 7 delivers sufficient compressed scavenge air and then the stopped auxiliary blower 16 is passed via a non-return valve 15.
With reference to the embodiments of Figs. 4 and 5 the large marine engine 100, i.e. a large turbocharged two- stroke internal combustion engine 100 of the uniflow type is configured to supply pressurized scavenging gas and/or
DK 181051 B1 exhaust gas to a consumer of pressurized gas 200. In this embodiment, structures and features that are the same or similar to corresponding structures and features previously described or shown herein are denoted by the same reference numeral as previously used for simplicity. The consumer of pressurized gas 200 can for example be an air lubrication system of a marine vessel in which the large marine engine 100 is installed for reducing the resistance of the marine vessel when moving through the water.
Scavenging gas is introduced into the cylinders 1 through the intake system, the intake system comprising the scavenge gas receiver 2 connected to the cylinders (1) via the scavenge ports 18.
Exhaust gas produced in the cylinders is exhausted through the exhaust system, the exhaust system comprising the exhaust gas receiver 3 connected to the cylinders 1 via the exhaust valves 4, A bypass system supplies bypassed pressurized gas to the consumer of pressurized gas 200 by taking out a controlled amount of scavenging gas from the intake system thereby bypassing the engine 100. Hereto, a first bypass conduit 43 connects to the intake system, at a position downstream of the outlet of the compressor 7, for example as shown at a position on the scavenge air receiver 2. The first bypass conduit or the 3 comprises in an embodiment a first bypass control valve 41 and connects to the consumer of pressurized gas 200. In an embodiment, the first bypass conduit 43 includes a first bypass blower 47 (compressor). The first bypass blower 47 is activated when the amount of pressurized gas supplied by the engine 100 without the support of the first bypass blower 47 is insufficient to i. DK 181051 B1 meet the demand of the consumer of pressurized gas 200.
Preferably, both or either the first bypass control valve 41 and the first bypass blower 47 are controlled by the controller 50, A bypass conduit comprising a first nonreturn valve 45 allows bypassing of the first bypass blower 47 when support by the first bypass blower 47 is not required. A pressure sensor 34 for sensing the pressure in the intake system downstream of the compressor 7 is arranged in the intake system and the signal from the pressure sensor 34 is communicated to the controller 50, for example by a signal line.
Alternatively, or in combination, the bypass system takes out a controlled amount of pressurized exhaust gas from the exhaust system thereby bypassing the turbine. Hereto, a second bypass conduit 49 connects to the exhaust system, at a position upstream of the inlet of the turbine 8, for example as shown at a position on the exhaust air receiver
3. The second bypass conduit 49 comprises in an embodiment a second bypass control valve 42 and connects to the consumer of pressurized gas 200. In an embodiment, the second bypass conduit 49 includes a second bypass blower 46 (compressor). The first bypass blower 47 is activated when the amount of pressurized gas supplied by the engine 100 without the support of the first bypass blower 47 is insufficient to meet the demand of the consumer of pressurized gas 200. A bypass conduit comprising a second nonreturn valve 44 allows bypassing of the second bypass blower 46 when support by the second bypass blower 46 is not required Preferably, both or either the second bypass control valve 42 and the second bypass blower 46 are controlled by the controller 50. A temperature sensor 33 for sensing the pressure in the exhaust system upstream of the turbine 8 is arranged in the exhaust system and the y DK 181051 B1 signal from the temperature sensor 33 is communicated to the controller 50, for example by a signal line.
The controller 50 is configured to adjust the amount of bypassed pressurized gas supplied to the consumer 200 as a function of the sensed scavenging gas pressure and/or exhaust gas temperature. Accordingly, the controller 50 is configured to limit the amount of bypassed pressurized gas supplied to the consumer of pressurized gas 200 when the sensed scavenging pressure is below a scavenging pressure threshold and/or the sensed exhaust gas temperature is above an exhaust gas temperature threshold.
In an embodiment, the controller 50 is configured to determine actual engine turbocharging effectiveness as a function of the sensed scavenging gas pressure and/or the sensed exhaust gas temperature and to limit the amount of bypassed pressurized gas supplied to the consumer of pressurized gas 200 as a function of the determined actual engine turbocharging effectiveness. Preferably, the controller 50 is configured to limit the amount of bypassed pressurized gas supplied to the consumer of pressurized gas 200 when the determined actual engine turbocharging effectiveness is below an actual engine turbocharging effectiveness threshold. The controller 50 is preferably configured to determine the actual available effectiveness excess of the one or more turbochargers 5 compared to a predetermined minimum engine turbocharging effectiveness threshold and also configured to limit the amount of bypassed pressurized gas supplied to the consumer of pressurized gas 200 as a function of the
. DK 181051 B1 determined available effectiveness excess of the one or more turbochargers 5.
In an embodiment, the controller 50 is configured to adjust the amount of bypassed pressurized gas supplied to the consumer 200 to the need for pressurized gas of the consumer of pressurized gas 200, preferably, in response to a signal from the consumer of pressurized gas 200 as long as the determined available effectiveness excess is not exceeded.
Preferably, the one or more turbocharges 5 have, at least in a given engine load range, a turbocharger effectiveness that exceeds a predetermined minimum required engine turbocharging effectiveness.
In the embodiment shown in Fig. 5, the one or more turbochargers 5 have a turbine 5 with a variable geometry turbine 8 allowing adjustment of the turbine flow area. The controller 50 is coupled to the one or more turbocharges 5 for controlling the variable geometry of the turbine 8 and the control unit 50 is configured to adjust the geometry of the turbine 8 to maximize the pressure delivered by the compressor 7 under the actual operating conditions of the engine 100 (as sensed by the controller 50), preferably by reducing the turbine flow area. In the embodiment of Fig. 4 the engine 100 comprises two or more turbochargers 5 and the controller 50 is configured to cut-out one or more of the two or more turbochargers 5, to maximize the pressure delivered by the compressor (s) 7 under partial load conditions of the engine 100. The control unit 50 is preferably configured to cut-out one or more of the two or more turbochargers 5 as a function of the engine load.
Cc DK 181051 B1 A switch point for cutting out one or more of the two or more turbochargers 5 is placed in the range of 60 to 80 % engine load, and the controller 50 is configured to cut out one or more of the two or more turbochargers 5 when the engine load is below the switch point. The switch point for turbocharger cut-out can be optimized (shifted to higher engine load) by using different installation parts or different frame sizes for the turbochargers 5.
In an embodiment (not shown) the engine 100 comprises more than two turbochargers 5 and the controller 50 is configured to activate one turbocharger 5 below a first cutout engine load threshold so that only one turbocharger 5 with a suitable flow area is running at low engine load. The controller 50 is further configured to activate two turbochargers 5 in an interval between the first cutout engine load threshold and a second cutout engine load threshold so that the combination of the flow area of the active turbochargers 5 is suitable running at medium engine load, and to activate three turbochargers 5 above the second cutout engine load threshold, so that the combined flow area of the active turbochargers 5 matches the operating conditions. The activate in sequence can be optimized by using turbochargers 5 with different flow areas, and is not limited to three turbochargers 5, there could be 4 or more turbochargers 5. The engine operation can be optimized by switching the turbochargers 5 on and off in a particular sequence so that only the turbocharger 5 or combination of turbocharges 5 with the most suitable flow area is running at a given load. For example, with increasing load, turbochargers 5 are separately switched on in order to increase the total turbocharger flow area
- DK 181051 B1 step by step until close to maximum engine load all turbochargers are active.
The controller 50 is operably coupled to the first electronic control valve 41 for controlling the amount of scavenge gas taken from the intake system and/or operably coupled to the second electronic control valve 42 for controlling the amount of exhaust gas taken from the exhaust system.
The controller 50 is in an embodiment configured to reduce the amount of bypassed pressurized gas supplied to the consumer 200 when the sensed scavenging gas pressure is below a scavenging gas pressure threshold. The scavenge gas pressure threshold is preferably adjusted according to ambient conditions, with the lowest threshold being applied in Arctic conditions and the highest scavenge gas pressure threshold being applied in tropical conditions. The appropriate level for the scavenging gas pressure threshold and adjustment of the scavenging gas pressure threshold is an embodiment based on tests or simulation of the engine
100. The controller 50 is in an embodiment configured to reduce the amount of bypassed pressurized gas supplied to the consumer 200 when the sensed exhaust gas temperature is above an exhaust gas temperature threshold. The exhaust gas temperature threshold is preferably adjusted according to ambient conditions, with the lowest exhaust gas temperature threshold being applied in Arctic conditions and the highest threshold being applied in tropical conditions. The appropriate level for the exhaust gas temperature threshold and adjustment of the exhaust gas temperature
DK 181051 B1 threshold is an embodiment based on tests or simulation of the engine 100. In the embodiment of Fig. 5 the engine 100 comprises a turbocharger 5 with variable turbine geometry allowing adjustment of the turbine flow area.
The controller 50 is configured to adjust the turbine flow area to maximize the pressure delivered by the compressor 7 under the actual operating conditions of the engine 100, preferably by reducing the turbine flow area of all of the turbochargers 5, to maximize the pressure delivered by the compressor (s) 7 under partial load conditions of the engine 100. In this embodiment, the engine 100 is provided with an optional Exhaust Gas Recirculation (EGR) system that comprises an EGR unit 60, an EGR blower 29 and and EGR valve 32. The EGR blower 29 and the EGR valve 32 are electronically controlled under the command of the controller 50. The EGR unit 60 comprises elements for treating the recirculated exhaust gas such as an EGR cooler 62 and/or a scrubber and water mist catcher 63. The controller 50 is in an embodiment configured to operate the engine 100 in a way to maximize scavenging gas pressure and/or maximize scavenging gas bypass mass-flow by controlling a PTI (Power Take In) functionality of a THS (Turbo Hydraulic System) installation on the one or more turbochargers 5. In another embodiment, the controller 50 is configured to operate the engine 100 in a way to maximize scavenging gas pressure and/or maximize scavenging gas bypass mass-flow by controlling the auxiliary blower installation 16 for additional pressurization at higher loads than usual.
i.
DK 181051 B1 In another embodiment the controller 50 is configured to operate the engine 100 in a way to maximize scavenging gas pressure and/or maximize scavenging gas bypass mass-flow by using the high turbocharging effectivity of a two-stage turbocharger installation.
In another embodiment, the controller 50 is configured to operate the engine 100 in a way to maximize scavenging gas pressure by controlling the cylinder bypass valve installation for pressurization.
In another embodiment, the controller 50 is configured to operate the engine 100 in a way to maximize exhaust gas bypass pressure by controlling the functionality of an EGR blower 29 in an EGR installation on a Tier 3 EGR engine 100 for additional pressurization in Tier 2 mode.
In another embodiment, the controller 50 is configured to operate the engine 100 in a way to maximize the delivered gas pressure by controlling an additional small turbocharger installation for pressurization of additional ambient air or bypassed scavenge air.
In another embodiment, the controller 50 is configured to operate the engine 100 in a way to maximize the delivered gas pressure by controlling an exhaust gas bypass to a power turbine installation for driving a dedicated additional electrical compressor.
In another embodiment, the controller 50 is configured to operate the engine 100 in a way to maximize the delivered gas pressure and/or mass-flow by controlling a hydraulically driven compressor powered by the engine/'s hydraulic pressure system installation.
>0 DK 181051 B1 The engine 100 is operated in accordance with a method that comprises bypassing a controlled amount of scavenging gas from the intake system or a controlled amount of pressurized exhaust gas from the exhaust.
The scavenging gas pressure in the intake system is sensed and/or the exhaust gas temperature in the exhaust system is sensed.
The amount of bypassed pressurized gas supplied to the consumer 200 is adjusted as a function of the sensed scavenging gas pressure and/or exhaust gas temperature.
The various measures to optimize the performance of the engine illustrated in the embodiments above can be combined, e.g. by combining sequential turbocharging (turbocharged cut out) with adjustment of the turbine flow area of one or more variable geometry turbocharges.
The method and engine have been described in conjunction with various embodiments herein.
However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.
In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality.
A single controller or other unit may fulfill the functions of several items recited in the claims.
The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage.
The reference signs used in the claims shall not be construed as limiting the scope.
Claims (13)
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DKPA202100342A DK181051B1 (en) | 2021-04-06 | 2021-04-06 | Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas |
JP2022052673A JP7512319B2 (en) | 2021-04-06 | 2022-03-29 | Large turbocharged two-stroke internal combustion engine and method for delivering mechanical energy and pressurized gas |
KR1020220040946A KR20220138816A (en) | 2021-04-06 | 2022-04-01 | Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas |
CN202210351274.XA CN115199401A (en) | 2021-04-06 | 2022-04-02 | Uniflow type large turbocharged two-stroke internal combustion engine and method of operating the same |
JP2024102661A JP2024125365A (en) | 2021-04-06 | 2024-06-26 | Large turbocharged two-stroke internal combustion engine and method for delivering mechanical energy and pressurized gas |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DKPA202100342A DK181051B1 (en) | 2021-04-06 | 2021-04-06 | Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas |
Publications (2)
Publication Number | Publication Date |
---|---|
DK202100342A1 DK202100342A1 (en) | 2022-10-18 |
DK181051B1 true DK181051B1 (en) | 2022-10-19 |
Family
ID=83658172
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DKPA202100342A DK181051B1 (en) | 2021-04-06 | 2021-04-06 | Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas |
Country Status (1)
Country | Link |
---|---|
DK (1) | DK181051B1 (en) |
-
2021
- 2021-04-06 DK DKPA202100342A patent/DK181051B1/en active IP Right Grant
Also Published As
Publication number | Publication date |
---|---|
DK202100342A1 (en) | 2022-10-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP7512319B2 (en) | Large turbocharged two-stroke internal combustion engine and method for delivering mechanical energy and pressurized gas | |
US8539770B2 (en) | Exhaust arrangement for an internal combustion engine | |
KR101513960B1 (en) | A large low-speed turbocharged two-stroke internal combustion engine with a dual fuel supply system | |
US20060021606A1 (en) | Internal combustion engine and working cycle | |
US20050098162A1 (en) | Internal combustion engine and working cycle | |
US20150136093A1 (en) | Engine Boosting System and Method Therefor | |
DK179313B1 (en) | Large turbocharged two-stroke compression-igniting engine with exhaust gas recirculation | |
Heim | Existing and future demands on the turbocharging of modern large two-stroke diesel engines | |
DK181051B1 (en) | Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas | |
DK181374B1 (en) | Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas | |
DK181437B1 (en) | Large turbocharged two-stroke internal combustion engine with turbochargers and method of operating such engine | |
DK181415B1 (en) | A large turbocharged two-stroke uniflow crosshead internal combustion engine and method for operating such engine | |
KR20160097142A (en) | Internal combustion engine, method for operating an internal combustion engine, cylinder, cylinder liner and closing plate for an internal combustion engine | |
DK181014B1 (en) | A large turbocharged two-stroke internal combustion engine with egr system | |
DK181455B1 (en) | Method and large two-stroke uniflow scavenged internal combustion engine for carbon dioxide capture | |
GB2377730A (en) | Air supply for pneumatically powered aircraft flight instruments taken from the supercharged induction system of a reciprocating-piston engine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PAT | Application published |
Effective date: 20221007 |
|
PME | Patent granted |
Effective date: 20221019 |