How to start combustion operation of a fuel-operated vehicle heating system.

Abstract

The present invention provides a method for initiating combustion operation of a fuel-operated vehicle heating system that prevents the occurrence of an acoustically perceptible combustion state during the startup phase when transitioning to combustion operation. [Solution] A method for starting combustion operation of a fuel-operated vehicle heating system, wherein the vehicle heating system comprises a group of combustion chamber components to which fuel and combustion air are supplied, a fuel pumping device for pumping fuel into the combustion chambers of the group of combustion chamber components, and a combustion air pumping device for pumping combustion air into the combustion chambers, the combustion air pumping device comprising at least one feed wheel that is rotatably driven to pump the combustion air,

Description

[Technical Field]

[0001] The present invention relates to a method for initiating combustion operation of a fuel-operated vehicle heating system. [Background technology]

[0002] Fuel-operated vehicle heating devices used as auxiliary heaters, parking heaters, or cabin heaters are started by supplying a preset amount of fuel and combustion air for the starting phase to the combustion chambers of the combustion chamber components of such vehicle heating devices to produce an ignitable mixture within these combustion chambers, particularly in the area of ​​the ignition mechanism, such as the glow plug. After ignition of this mixture, a flame is generated within the combustion chamber components. Until stable combustion or a fully formed flame is obtained, locally unstable combustion conditions may occur based on the thermal state within the combustion chamber components, particularly based on the relatively low temperature of the flame tubes of the combustion chamber components surrounding the formed flame. These unstable combustion conditions, under appropriate excitation, may lead to acoustically perceptible combustion resonances. [Overview of the project] [Problems that the invention aims to solve]

[0003] The object of the present invention is to provide a method for initiating combustion operation of a fuel-operated vehicle heating system that can prevent the occurrence of an acoustically perceptible combustion state during the startup phase when transitioning to combustion operation. [Means for solving the problem]

[0004] According to the present invention, the problem is solved by a method for starting the combustion operation of a fuel-operated vehicle heating device, wherein the vehicle heating device is - A group of combustion chamber components to which fuel and combustion air should be supplied. - Fuel pumping device for pumping fuel into the combustion chamber of the combustion chamber configuration group. - A combustion air pumping device for pressurizing combustion air into a combustion chamber, comprising at least one feed wheel that is rotatably driven to pressurize combustion air. It is solved by a method that includes [the necessary features / methods].

[0005] The above method involves the following steps, namely, a) In the ignition phase after the generation of a start command to initiate combustion operation, in order to provide an ignitable fuel-combustion air mixture, the combustion air pumping device for pumping combustion air into the combustion chamber is operated at the ignition phase rotation speed assigned to the ignition phase, and the fuel pumping device for pumping fuel into the combustion chamber is operated at the ignition phase pumping rate assigned to the ignition phase. b) In the first rotational speed adjustment stage following the ignition stage, the rotational speed of the combustion air supply device is changed to a flame stabilization stage rotational speed that does not lead to the occurrence of combustion resonance in the combustion chamber components. c) In the flame stabilization stage following the first rotational speed adjustment stage, the combustion air supply device is operated substantially at the flame stabilization stage rotational speed, d) In the second rotation speed adjustment stage following the flame stabilization stage, the rotation speed of the combustion air supply device is reduced to the combustion operating rotation speed. e) In the combustion operation following the second rotational speed adjustment stage, the combustion pneumatic pump is operated at substantially the combustion operating rotational speed. Includes steps.

[0006] In the method according to the present invention, the rotational speed of the combustion pneumatic pump is changed following the ignition stage, and therefore immediately after ignition of the mixture of fuel and combustion air formed in the combustion chamber, so that the excitation frequency of the combustion pneumatic pump, which is substantially determined by the rotational speed of the combustion pneumatic pump and the configuration of the feed wheel of the combustion pneumatic pump, particularly the number of feed vanes of the feed wheel, is not within the range of the resonant frequencies of the combustion that takes place in the combustion chamber or in the flame tubes leading to the combustion chambers of the combustion chamber configuration group to form a flame. Depending on the configuration of the vehicle heating equipment and the surrounding conditions, such a resonant frequency may be in the range of 70 to 80 Hz.

[0007] Therefore, it is possible to avoid the excitation of combustion resonance in the combustion chamber components, which is acoustically perceptible, at the stage when the combustion chamber components have not yet reached operating temperature and therefore thermally unstable conditions exist, particularly in the region of the combustion chamber components surrounding the flame that is formed. At the same time, at this stage when stable combustion occurs, the region of the combustion chamber components surrounding the flame, particularly the flame tube of the combustion chamber components, can be brought to operating temperature. Once this state is reached, even if the excitation frequency of the combustion pneumatic pump is within a value range that is essentially critical with respect to the excitation of combustion resonance, the thermal interaction between the flame and, for example, the flame tube is generally unlikely to cause the generation of combustion resonance.

[0008] In order to prevent excitation of combustion resonance on the one hand and the release of an excessive proportion of harmful substances or unburned fuel on the other hand by changing the rotational speed of the combustion pneumatic pump, in step b), it is proposed to increase the rotational speed of the combustion pneumatic pump from the ignition stage rotational speed to a flame stabilization stage rotational speed that does not lead to the occurrence of combustion resonance in the combustion chamber components, so that in step c), a mixture of fuel and combustion air at a ratio below the stoichiometric ratio is generated in the combustion chamber.

[0009] In particular, in this case, step b) may specify that the rotational speed of the combustion pneumatic feeder be increased such that the mixture of fuel and combustion air produced in the combustion chamber has a lambda value of less than 0.8. Such a low lambda value has been shown to be achieved by a high pumping rate and, consequently, a high rotational speed of the combustion pneumatic feeder, such that periodic pressure fluctuations generated in the pumped air by the rotation of the feedwheel of the combustion pneumatic feeder and propagated into the combustion chamber region cannot lead to the excitation of combustion resonance.

[0010] In order to reach ignition as quickly as possible after the generation of the start command, in step a), the ignition stage rotation speed and the ignition stage pressure rate can be adjusted to provide a fuel-combustion air mixture that is substantially at the stoichiometric ratio, or, for example, slightly above the stoichiometric ratio.

[0011] To achieve a substantially uniform transition between various rotational speed states of the combustion pneumatic pump, it is proposed that in step b), the rotational speed be increased at a substantially constant rate of change, and / or in step d), the rotational speed be decreased at a substantially constant rate of change.

[0012] In order to reach an operating stage in which the flame can be stabilized as quickly as possible, it is proposed that in step b), the rotational speed is increased by a first maximum value of the rotational speed change rate, and in step d), the rotational speed is decreased by a second maximum value of the rotational speed change rate, where the first maximum value is greater than the second maximum value.

[0013] In this case, particularly preferably, the first maximum value of the rate of change substantially corresponds to the maximum adjustable rate of change in the combustion pneumatic feeder for increasing the rotational speed. This means utilizing structural or control technology possibilities as much as possible to rapidly increase the rotational speed of the combustion pneumatic feeder or at least one feedwheel of the combustion pneumatic feeder without incurring the risk of damaging the system area, especially the combustion pneumatic feeder. The maximum adjustable rate of change in rotational speed can be defined or limited, for example, by the maximum voltage that can be applied to the electric motor of the combustion pneumatic feeder, i.e., the maximum voltage provided by the onboard power supply voltage network, or by the maximum permissible operating voltage or average operating voltage for such an electric motor. In electrically rectified motors, the change in rotational speed can be controlled by voltage. Such rapid changes in the rotational speed of the combustion pneumatic feeder ensure that the excitation frequency range in which the resonant frequency of the combustion pulsation of the formed flame also exists also passes very quickly, thereby avoiding the occurrence of combustion resonance.

[0014] A rapid transition to the flame stabilization stage can also be assisted by the ignition stage duration being in the range of 2 seconds to 4 seconds, preferably about 3 seconds.

[0015] It may be specified that the duration of the flame stabilization stage is adjusted depending on the ambient temperature and / or the temperature in the region of the combustion chamber group so as to take into account the ambient conditions during flame stabilization. Advantageously, in this case, the duration of the flame stabilization stage is increased in response to a decrease in the ambient temperature and / or the temperature in the region of the combustion chamber group.

[0016] In order to ensure that a mixture below the stoichiometric air-fuel ratio consisting of fuel and combustion air is produced in the flame stabilization stage, the fuel pumping rate in the first rotational speed adaptation stage and the flame stabilization stage may substantially correspond to the ignition stage pumping rate.

[0017] To transition to the combustion operation following the start-up stage, in the second rotational speed adaptation stage, the fuel pumping rate can be adjusted to the combustion operation pumping rate set for the combustion operation. If the target heating output of the vehicle heating device set for the subsequent combustion operation requires a larger amount of fuel, the fuel pumping rate can be increased accordingly in the second rotational speed adaptation stage. If the vehicle heating device is operable, for example, only at one heating output stage, and thus, for example, the fuel pumping device can only be switched on and off, and its pumping amount is substantially unchangeable, the combustion operation pumping rate set for the subsequent combustion operation may correspond to the ignition stage pumping rate already adjusted in advance, for example, for the ignition stage. Thereby, adjusting the fuel pumping rate to the combustion operation pumping rate set for the subsequent combustion operation substantially includes maintaining the fuel pumping rate already utilized in advance.

[0018] The present invention will be described in detail below with reference to the accompanying drawings.

Brief Description of the Drawings

[0019] [Figure 1] It is a schematic diagram showing a fuel-operated vehicle heating device. [Figure 2] It is a time graph showing an example of the change in the amount of fuel or combustion air pumped at the start stage of the combustion operation of a fuel-operated vehicle heating device.

Embodiments for Carrying Out the Invention

[0020] In Fig. 1, a fuel-operated vehicle heating device 10 is shown in a schematic diagram. The vehicle heating device 10 includes a combustion chamber group 12 as a central component group. This combustion chamber group has a combustion chamber 18 defined by a peripheral wall 14 and a bottom wall 16, and a flame tube 22 connected to the peripheral wall 14 in the region of, for example, a flame throttle 20.

[0021] The combustion chamber 12 is surrounded at least in a predetermined region by a heat exchanger group 24 including a heat transfer medium flow chamber 30 defined by a pot-shaped inner housing 26 and a pot-shaped outer housing 28. The liquid medium to be heated can flow into the heat transfer medium flow chamber 30 from the heat transfer medium inlet 32, flow through the heat transfer medium flow chamber for heat absorption, and flow out again from the heat transfer medium outlet 34. It is supplemented that when the vehicle heating device 10 is formed to heat a gaseous heat transfer medium, for example, air introduced into the vehicle interior, the combustion chamber 12 may be arranged in a housing through which the air to be heated can flow.

[0022] To generate heat, the liquid fuel taken out from the tank is supplied into the combustion chamber 18 by, for example, a fuel pumping device 36 formed as a metering pump. When the combustion chamber group 12 is configured as an evaporator burner, the liquid fuel can be supplied to, for example, a porous evaporator medium and discharged into the combustion chamber 18 as a gas through this. When configured as a spray burner, the liquid fuel can be supplied to a spray nozzle, and the fuel is discharged into the combustion chamber 18 in the form of droplets through this spray nozzle.

[0023] To provide the oxygen necessary for combustion, combustion air is supplied into the combustion chamber 18 by a combustion air pumping device 38, which is formed, for example, as a lateral passage fan. The combustion air pumping device 38 has a rotatable feed wheel 40 for pumping the combustion air, and the feed wheel is generally driven and rotated by an electric motor.

[0024] The fuel pumping device 36 and the combustion air pumping device 38 are under the control of a control unit 42. This control unit can receive information regarding the rotational speed of the feed wheel 40 of the combustion air pumping device 38 from, for example, a rotational speed sensor 44 assigned to the combustion air pumping device 38, and the control unit 42 can take this actual rotational speed into consideration and control the combustion air pumping device 38 so that the feed wheel 40 of the combustion air pumping device rotates at a target rotational speed specified for a given operation. As an alternative to this closed-loop controlled operation of the combustion air pumping device 38, the combustion air pumping device can be operated in an open-loop controlled operation by applying a voltage or average voltage corresponding to the target rotational speed of the feed wheel 40.

[0025] The fuel pumping device 36 is also under the control of the control device 42, and especially when it is configured as a metering pump, the fuel pumping device 36 can be controlled to operate at a clock frequency corresponding to such a target fuel amount predetermined for a given operation, in order to adjust the amount of fuel to be supplied into the combustion chamber 18.

[0026] To ignite the mixture of fuel and combustion air that is present or formed within the combustion chamber 18, the combustion chamber component 12 has an ignition mechanism 46, which is formed, for example, as a glow ignition pin. Since this ignition mechanism is also under the control of the control unit 42, when the combustion operation of the vehicle heating equipment 10 starts, the control unit 42 controls the ignition mechanism 46 to generate a temperature sufficient for ignition of the mixture of fuel and combustion air that is formed or generated within the combustion chamber 18.

[0027] The following describes a method for operating the vehicle heating equipment 10 during the startup phase to initiate combustion operation, with reference to Figure 2.

[0028] At time t0, the vehicle's control unit 42 or other system area generates a start command to begin operation of the vehicle heating equipment 10, including a starting phase leading to continuous combustion operation. After the start command is generated or supplied, the control unit 42 activates the pressurizers 36, 38, which are initially not in operation, thereby setting the rotational speed N of the combustion air pressurizer 38 or the feed wheel 40 of the combustion air pressurizer to the ignition speed N up to time t1 in the ignition phase following time t0. Z For example, the rotational speed is increased at a substantially constant rate of change until the end of the ignition phase at time t2.

[0029] As the combustion air pumping device 38 starts operating and the rotational speed N of the feed wheel 40 increases, the fuel pumping device 36 also operates, and the fuel pumping rate F of the fuel pumping device is, for example, substantially constant at the ignition stage rotational speed N Z Ignition stage pressure rate F corresponding to Z It rises to. The fuel feed rate F can be increased in parallel with the rotational speed N in order to provide a mixture of combustion air and fuel that substantially corresponds to the ratio provided for the ignition stage throughout the entire ignition stage, thereby the ignition stage feed rate F Z This is effectively achieved at time t1, and then, throughout the remainder of the ignition stage, combustion air and fuel are continuously supplied at the mixture ratio to be set for the ignition stage, for example, substantially at the stoichiometric air-fuel ratio, i.e., for a lambda value of 1. This ratio may deviate slightly from a lambda value of 1 for the ignition stage, for example, in the direction of greater than the stoichiometric air-fuel ratio, or optionally in the direction of less than the stoichiometric air-fuel ratio. Depending on the structural mode of the vehicle heating equipment 10, the ignition stage rotational speed N Z and ignition stage pressure rate F Z This can be achieved at different points in time.

[0030] The ignition phase between time points t0 and t2 may be designed, for example, such that this ignition phase lasts for about 3 seconds. Thereby, during this ignition phase, on the one hand, an ignitable mixture composed of fuel and combustion air can be generated in a predefined quantitative ratio for the ignition phase, and on the other hand, ignition can also be carried out by excitation of the ignition mechanism 46 in this ignition phase. This means that combustion already starts in the combustion chamber 18 in the ignition phase and the flame F begins to form.

[0031] Following the ignition phase, in the first rotational speed adaptation phase, the rotational speed N of the combustion air delivery device 38 is significantly increased from time point t2 to time point t3, and thus the delivery rate is also significantly increased. Preferably, in the first rotational speed change phase, it is assumed that the rotational speed N is increased at the maximum adjustable rotational speed change rate in the combustion air delivery device 28. This maximum adjustable rotational speed change rate is, for example, maximally provided by the vehicle's on-board power supply voltage network and may be limited by the on-board power supply voltage applied continuously, i.e., at a duty ratio of 100%, to the electric motor of the rotational speed delivery device 38 in this state. If this on-board power supply voltage is higher than, for example, the voltage that can be maximally applied to the electric motor of the combustion air delivery device 38, the maximum adjustable rotational speed change rate may be limited by the maximally available voltage for the combustion air delivery device 38, or by setting a correspondingly limited duty ratio with respect to the voltage applied to the electric motor of the combustion air delivery device 38, or by an adjustable average voltage.

[0032] In the first rotational speed adaptation phase, the rotational speed N is increased, for example, at a substantially constant rotational speed change rate to the rotational speed N in the flame stabilization phase corresponding to the flame stabilization phase following time point t3. F In the flame stabilization phase, until time point t4, the rotational speed N in the flame stabilization phase F is maintained substantially constant, for example.

[0033] The rotational speed N of the combustion air delivery device 38 is significantly higher in the flame stabilization phase rotational speed N Z than in the ignition phase rotational speed N FBy rapidly increasing the excitation frequency, it is achieved that the excitation frequency of the combustion air pump 38 during the flame stabilization stage becomes significantly higher than the resonance frequency due to combustion heterogeneity in the formed flame F. When such combustion heterogeneity is excited by an excitation frequency within its resonance frequency range, acoustically perceptible combustion resonance may occur in the combustion chamber configuration 12, especially when the surrounding area of ​​the combustion, i.e., particularly the peripheral wall 14 or flame tube 22, has not yet reached operating temperature, and the thermal interaction between the formed flame and its system region promotes the occurrence of combustion heterogeneity.

[0034] Excitation of such vibrations in combustion, which can undesirably lead to combustion resonance, can occur in the region of the combustion air pump 38 by periodic pressure pulsations generated by the rotation of the feed wheel 40, and such periodic pressure pulsations may propagate into the combustion air, into the region of the combustion chamber 18 or the flame F being formed. The frequency of such periodic pressure pulsations generated by the rotation of the feed wheel 40 can substantially be determined by the product of the rotational speed of the feed wheel 40 and the number of feed vanes on the feed wheel. For example, if the combustion air pump 38 is configured as a lateral passage fan, the feed vanes of the combustion air pump's feed wheel move through a demarcation region that separates the inlet and outlet of the ring passage of the lateral passage fan with each rotation of the feed wheel, and in this case, each movement of the feed vanes may lead to pressure fluctuations that spread through this demarcation region into the combustion air being pumped.

[0035] The rotational speed N of the combustion pneumatic feeder 38 or the feed wheel 40 of the combustion pneumatic feeder is set to the rotational speed N of the flame stabilization stage. ZBy rapidly increasing the rotational speed N of the combustion pneumatic pump 38, it is possible to quickly pass through the excitation frequency range which potentially carries the risk of combustion resonance, and following the flame stabilization stage, a mixture of fuel and combustion air significantly below the stoichiometric air-fuel ratio is generated and burned in the combustion chamber 18. This ensures, on the one hand, that the introduced fuel can be completely burned even during the flame stabilization stage, and on the other hand, helps to rapidly heat the combustion chamber components 12, particularly the flame tube 22, to an operating temperature that does not lead to the occurrence of combustion heterogeneity that promotes combustion resonance, even in the thermal interaction between the flame F and, for example, the flame tube 22. Increasing the rotational speed N of the combustion pneumatic pump 38 so that the mixture of fuel and combustion air formed in the combustion chamber 18 has a lambda value of less than 0.8 results in a high rotational speed of the combustion pneumatic pump 38, and consequently a high excitation frequency, which has been shown to prevent excitation of combustion resonance even when the flame or combustion is not yet stabilized.

[0036] The rotational speed, excitation frequency, or excitation frequency range of the combustion air supply unit 38, which poses a risk of combustion resonance within the vehicle heating equipment 10, can be determined, for example, in an assembled vehicle heating equipment, by changing the rotational speed of the combustion air supply unit 38 during the startup phase, taking into account various ambient conditions, so that combustion resonance actually occurs. If this critical rotational speed or critical rotational speed range is known, then the flame stabilization stage rotational speed N F This can be selected or preset so that, even when dealing with various surrounding conditions, there is a sufficient safety interval between the rotational speed that promotes the occurrence of combustion resonance and the rotational speed.

[0037] The formation and stabilization of flame F are highly dependent on ambient conditions, such as fuel temperature, the temperature of the combustion air introduced into the combustion chamber 18, the temperature of the combustion chamber 12 itself, air humidity, and air pressure. Therefore, the duration of the flame stabilization phase, i.e., the interval between time points t3 and t4, can be adjusted depending on these ambient conditions, particularly the ambient temperature or the temperature of the combustion chamber itself. These temperatures can be detected, for example, by appropriate sensors, and the output signals from these sensors can be used in the control unit 42 to adjust the duration of the flame stabilization phase. In this case, the duration of the flame stabilization phase can be set to increase as the ambient air temperature or the temperature in the combustion chamber components 12 decreases. For example, it has been confirmed that when the temperature around the vehicle heating equipment 10, and consequently the temperature of the combustion chamber components 12, is room temperature, i.e., approximately 20°C, it is desirable for the duration of the flame stabilization phase to be in the range of 40 to 50 seconds. This promotes stable combustion, especially through sufficient heating of the combustion chamber components themselves. In effect, when the temperature of the combustion air introduced into the combustion chamber 18, or the ambient temperature of the combustion chamber components 12, particularly the flame tube 22, is approximately -40°C, a flame stabilization phase lasting several minutes may be required to stabilize the combustion.

[0038] At the end of the flame stabilization stage at time t4, in the second rotational speed adjustment stage up to time t5, the rotational speed N of the combustion air pump 38 or feed wheel 40 is reduced at a rotational speed change rate that is lower than the value of the rotational speed change rate in the first rotational speed adjustment stage between time t2 and t3. The required heating output is met by the ignition stage pumping rate F of the fuel pump 36. Z If a larger amount of fuel is required than the amount of fuel pressurized into the combustion chamber 18 by operating in this manner, for example, in the second rotational speed adjustment stage, the combustion operation rotational speed N is set in accordance with the heating output that should be adjusted in this case, for example, depending on the ambient conditions or the temperature of the medium to be heated, for subsequent combustion operation from time t5 onward. VAs the rotational speed N decreases in this way, the fuel pumping rate F of the fuel pumping device 36 also decreases, and the combustion operation pumping rate F corresponding to the next combustion operation to be performed or the heating output provided for that operation also decreases. V It can be increased to this extent. If the amount of fuel pumped in the ignition stage is sufficient for the subsequent combustion operation, or if the vehicle heating equipment 10 can operate with basically only a single heating output stage, the fuel pumping rate F may be kept substantially unchanged during the transition from the flame stabilization stage to the combustion operation, that is, between time points t4 and t5.

[0039] Combustion operating speed N V and combustion operation pressure feed rate F V Essentially, for combustion operations performed after time point t5, the amount of mixture consisting of combustion air and fuel set to adjust the required heating output is calculated so that it is supplied at the mixture ratio set for the combustion operation, for example, the stoichiometric air-fuel ratio or a mixture ratio slightly below the stoichiometric air-fuel ratio.

[0040] Using the method described above, the vehicle heating device 10 can transition to combustion operation during a cold start, or, for example, when restarting after the flame has gone out, without generating any acoustically perceptible combustion resonance outside the vehicle heating device 10 when the flame F is formed. At the same time, by operating with a mixture of fuel and combustion air that is significantly below the stoichiometric air-fuel ratio, substantially unburned fuel does not flow out of the combustion chamber components 12 and does not leave the exhaust gas flow chamber 48 formed between the flame tube 22 and the heat exchanger components 24 and head towards the exhaust gas outlet 50 together with the combustion exhaust gas already generated when the flame F was formed.

[0041] The method according to the present invention may differ in various respects from the method described above and shown in Figure 2. For example, in at least one of the rotational speed adjustment stages, the rotational speed N of the combustion air pump 38 can be changed by different rotational speed change rates, thereby creating a temporary maximum rotational speed change rate in one or both of the rotational speed adjustment stages. When the rotational speed change rate is constant, this rotational speed change rate corresponds to the maximum rotational speed change rate in each rotational speed adjustment stage.

[0042] In the ignition and / or flame stabilization phases, unlike the substantially constant rotational speed N or fuel feed rate F shown in the figure, the rotational speed N and / or fuel feed rate F are maintained at approximately the levels shown in the figure, but may be expected to vary slightly within this range. For example, from time t1 or time t2 onward, the fuel feed rate F increases at a relatively small rate of change, almost constant up to time t5, for example, so that from time t5 onward, without further adjustment measures, the fuel is supplied to the combustion operation feed rate F that should be set for the combustion operation to be carried out in this case. V It is assumed that this is supplied into the combustion chamber 18.

Claims

1. A method for starting combustion operation of a fuel-operated vehicle heating device, wherein the vehicle heating device is - Combustion chamber components (12) to which fuel and combustion air should be supplied, - Fuel pumping device (36) for pumping fuel into the combustion chamber (18) of the combustion chamber configuration group (12), - A combustion air pumping device (38) for pumping combustion air into the combustion chamber (18), the combustion air pumping device (38) comprising at least one feed wheel (40) that is rotatably driven to pump combustion air. It is equipped with, The method involves the following steps, namely: a) In the ignition stage after the generation of a start command to initiate combustion operation, in order to provide an ignitable fuel-combustion air mixture, the combustion air pumping device (38) for pumping combustion air into the combustion chamber (18) is configured to have an ignition stage rotation speed (N) assigned to the ignition stage. Ｚ The fuel pumping device (36) for pumping fuel into the combustion chamber (18) is operated at the ignition stage pressure rate (F) assigned to the ignition stage. Ｚ ) Activate it with b) In the first rotational speed adjustment stage following the ignition stage, the rotational speed (N) of the combustion air supply device (38) is set to a flame stabilization stage rotational speed (N) that does not lead to the occurrence of combustion resonance in the combustion chamber configuration group (12). Ｆ ) to change to, c) In the flame stabilization stage following the first rotation speed adjustment stage, the combustion air supply device (38) is substantially set to the flame stabilization stage rotation speed (N Ｆ ) Activate it with d) In the second rotation speed adjustment stage following the flame stabilization stage, the rotation speed (N) of the combustion air supply device is set to the combustion operation rotation speed (N) Ｖ ) to lower it, e) In the combustion operation following the second rotational speed adjustment step, the combustion air supply device (38) is set to substantially the combustion operation rotational speed (N Ｖ ) Activate A method that includes steps.

2. In step b), the flame stabilization stage rotation speed (N) is set such that it does not lead to the occurrence of combustion resonance in the combustion chamber configuration group (12). Ｆ In order to provide the combustion air pumping device (38), the rotational speed (N) is set to the ignition stage rotational speed (N) Ｚ The method according to claim 1, characterized in that, in step c), the mixture consisting of fuel and combustion air is increased to a ratio less than the stoichiometric air-fuel ratio to be generated in the combustion chamber (18).

3. The method according to claim 2, wherein in step b), the rotational speed (N) of the combustion air pumping device (38) is increased so that the mixture of fuel and combustion air generated in the combustion chamber (18) has a lambda value of less than 0.

8.

4. In the step a), the ignition stage rotational speed (N Ｚ ), and the ignition stage pumping rate (F Ｚ ), are adjusted to provide a fuel-air mixture having a substantially stoichiometric ratio, according to any one of claims 1 to 3.

5. The method according to any one of claims 1 to 4, characterized in that, in step b), the rotational speed is increased at a substantially constant rate of change in rotational speed, and / or, in step d), the rotational speed is decreased at a substantially constant rate of change in rotational speed.

6. The method according to any one of claims 1 to 5, characterized in that, in step b), the rotational speed (N) is increased by the maximum first value of the rotational speed change rate, and in step d), the rotational speed (N) is decreased by the maximum second value of the rotational speed change rate, wherein the maximum first value is greater than the maximum second value.

7. The method according to claim 6, characterized in that the maximum first value of the rate of change substantially corresponds to the rate of change of rotation that can be adjusted to the maximum extent in the combustion air pressurizing device (38) to increase the rotational speed (N).

8. The method according to any one of claims 1 to 7, characterized in that the duration of the ignition stage is in the range of 2 to 4 seconds, preferably about 3 seconds.

9. The method according to any one of claims 1 to 8, characterized in that the duration of the flame stabilization stage is adjusted depending on the ambient temperature and / or the temperature in the region of the combustion chamber components.

10. The method according to claim 9, characterized in that the duration of the flame stabilization step is extended in accordance with the decrease in ambient temperature and / or temperature in the region of the combustion chamber components.

11. The fuel supply rate (F) in the first rotational speed adjustment stage and the flame stabilization stage is substantially the same as the ignition stage supply rate (F Ｚ The method according to any one of claims 1 to 10, characterized in that it corresponds to ).

12. In the second rotational speed matching step, the fuel pumping rate (F) is set to the combustion operation pumping rate (F) set for the combustion operation. Ｖ The method according to any one of claims 1 to 11, characterized by adjusting so that ).

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