A fuel atomizing nozzle

Abstract

The present invention provides a fuel atomizing nozzle (1) for handling at least two fuels and an atomizing fluid, the fuel atomizing nozzle (1) comprising a solid body (10) having a mainly cylindrical shape around a longitudinal axis (X) defining a first end (11), a second end (12) and a contour surface (16) extending there between connecting the two ends (11, 12), wherein the first end (11) comprises at least one outlet (17), wherein the fuel atomizing nozzle (1) further comprises a fluid compartment (14) being arranged centrally around the longitudinal axis (X) in the solid body (10), at least a first and a second fuel compartment (15a, 15b) being arranged in a radial plane between the fluid compartment (14) and the contour surface (16), the fuel compartments (15a, 15b) having an annular shape, the at least first and second fuel compartments (15a, 15b) being connected to a pre-filling chamber (35) by at least a first and a second fuel channel (25a, 25b), respectively, at least one mixing chamber (40) being arranged between the fluid compartment (14) and the at least one outlet (17), and a fluid channel (24) connecting the at least one mixing chamber (40) and the fluid compartment (14), wherein the pre-filling chamber (35) has an annular shape, and the pre-filling chamber (35) is connected via a pre-filling channel (45) to the at least one mixing chamber (40).

Description

[0001] A FUEL ATOMIZING NOZZLE

[0002] Field of the Invention

[0003] The present invention relates to the field of nozzles for fuel atomizers, and more specifically to nozzles for fuel atomizers used for boilers. The present invention also relates to a method of atomizing fuel by the use of a fuel atomizing nozzle and a system of a fuel atomizing nozzle.

[0004] Background of the Invention

[0005] Boilers are used in a wide range of applications such as in power plants, on-board ships and, for processing of food and vegetable oils, etc. One type of boiler is the steam boiler that produces pressurized steam by heating water to its boiling point using a combustion process.

[0006] For a boiler the combustion is done in a burner that mixes fuel and air in order to push heat into the steam boiler system. The mixture of fuel and air is combusted and for having an efficient combustion the fuel is atomized before being combusted.

[0007] During operation of a boiler a fuel atomizing nozzle is used in the burner for atomizing the fuel in order to achieve a fine spray of the fuel, so it is efficiently combusted.

[0008] An atomizing nozzle might be referred to as an atomizer, which disperses a liquid by transforming it into a spray. A nozzle can have one or several outlets. In a burner for a boiler the nozzle normally comprises several outlets.

[0009] A well-known type of nozzle is the so called Y jet nozzle. In this type of nozzle, a number of ports are arranged at an angle to the burner axis to produce a hollow conical spray nozzle. Each port or outlet has a co-axial fluid port for injecting a compressed fluid and a fuel port entering at an angle. The fluid and the fuel are mixed in the exit port, this mixture then expands out of the port and forms a spray. Often the jet of fuel from the fuel port impinges on the one side of the exit port and forms a thick film. This thick film is then transmitted through the exit port and lead to formation of larger fuel droplets than desired. This may result in smaller sized droplets are produced at the outer radius of an exit port and larger droplets are produced at the inner radius of an exit port. If droplets are too large the combustion is non-effective.

[0010] There are thus challenges of known nozzles to achieve an efficient full combustion. Problems with irregular spray having varying droplet size and exiting intermittently. This leads to a non-effective combustion that is environmentally non- sustainable.

[0011] There is thus a need in the art for improved fuel atomizing nozzles.

[0012] Summary of the Invention

[0013] A main object of the present invention is to provide a fuel atomizing nozzle for handling at least two fuels and an atomizing fluid having an improved function to create droplets having regular size resulting in an even spray, leading to more efficient combustion.

[0014] As a first aspect of the invention, there is provided a fuel atomizing nozzle for handling at least two fuels and an atomizing fluid, the fuel atomizing nozzle comprising a solid body having a mainly cylindrical shape around a longitudinal axis (X) defining a first end, a second end and a contour surface extending there between connecting the two ends, wherein the first end comprises at least one outlet. The fuel atomizing nozzle further comprises a fluid compartment being arranged centrally around the longitudinal axis in the solid body, at least a first and a second fuel compartment being arranged in a radial plane between the fluid compartment and the contour surface, the fuel compartments having an annular shape, the at least first and second fuel compartments being connected to a pre-filling chamber by at least a first and a second fuel channel, respectively, at least one mixing chamber being arranged between the fluid compartment and the at least one outlet, and a fluid channel connecting the at least one mixing chamber and the fluid compartment. The pre-filling chamber has an annular shape, and the pre-filling chamber is connected via a pre-filling channel to the at least one mixing chamber.

[0015] As used herein, the term “axially” denotes a direction which is parallel to a longitudinal axis (X). Accordingly, relative terms such as “above”, “upper”, “top”, “below”, “lower”, and “bottom” refer to relative positions along the longitudinal axis (X). Correspondingly, the term “radially” denotes a direction extending radially from the longitudinal axis (X). A “radially inner position” thus refers to a position closer to the longitudinal axis (X) compared to “a radially outer position”. A radial plane is a plane having its normal parallel to the longitudinal axis (X). An axial plane is a plane having its normal perpendicular to the longitudinal axis (X).

[0016] The first end corresponds to the upper end of the nozzle and the second end corresponds to the lower end of the nozzle. The fuel compartments having annular shape mean that these compartments are concentric with each other around the longitudinal axis (X). The first fuel compartment has a radially inner position in relation to the second fuel compartment. The radial extension in the radial plane of the first fuel compartment may be the same as the radial extension in the radial plane of the second fuel compartment. Both compartments may also have the same longitudinal extension in the axial plane. The extensions in the radial plane and in the axial plane may also differ between the first and the second compartment.

[0017] The atomizing fluid can be air or steam, i.e. water vapour. The steam can be saturated or superheated.

[0018] The contour surface can be a cylinder having the same diameter at the first end and the second end of the nozzle. The contour surface can also be a cylinder having a varying diameter along the cylinder, such as a smaller diameter at the first end in comparison to the second end. The transition from one diameter to another can be stepwise or chamfered.

[0019] The pre-filling chamber has an annular shape having an extension in the radial plane and in the axial plane. The extension in the axial plane may be larger than the extension in the radial plane. The pre-filling chamber is concentric with the fuel compartments. The location of the pre-filling chamber is closer to the first end than the fuel compartments and the pre-filling chamber is located radially outside of the mixing chamber. When taking a cross section in the axial plane the pre-filling chamber may be seen as rectangular or triangular. The outer radial wall of the pre-filling chamber may be parallel with the longitudinal axis. The inner radial wall of the pre-filling chamber may be parallel with the longitudinal axis or may be angled in relation to the longitudinal axis such that the inner wall has a smaller radius at the lower end in comparison to the upper end. The inner radial wall of the pre-filling chamber may also comprise a combination of being parallel with the longitudinal axis and being angled in relation to the longitudinal axis.

[0020] The pre-filling channel connects the pre-filling chamber and the mixing chamber. The cross sectional shape of the channel could be smooth like circular or oval, or it could be teardrop shaped, triangular or rectangular.

[0021] The first aspect of the invention is based on the insight that evenly sized droplets, not being too big, lead to a fine spray. A fine spray leads to efficient combustion.

[0022] The inventors have thus found that it is advantageous to have an annular pre-filling chamber being located around the inside of the nozzle that gives a turbulent circulating flow of fuel, so that the fuel reaches the mixing chamber with high speed. In the mixing chamber the fuel is then mixed with the fluid. The mixture of fuel and fluid is thereafter being discharged through the outlet in a highly sheared manner, resulting in a fine spray with small evenly sized droplets throughout the entire opening of the outlet, i.e. the exit port.

[0023] In embodiments of the first aspect, the body is one single solid part. To achieve a nozzle made of one single piece a manufacturing method could be by additive manufacturing. However, the nozzle could also be manufactured according to conventional methods. Known nozzles are often made of two parts being connected. But, when two parts should stick together there are often challenges to secure that they stay tightly connected throughout the lifetime of the nozzle or there might be stresses built into the nozzle leading to shorter lifetime. So, a single solid part overcomes these disadvantages.

[0024] In embodiments of the first aspect, one outlet is connected to one mixing chamber, respectively. Thus, ensuring a direct spray of the mixture of fuel and fluid. The fuel reaching the mixing chamber from the pre-filling channel and the fluid reaching the mixing chamber from the fluid channel.

[0025] In embodiments of the first aspect, the first end comprises at least one chamfered surface comprising the at least one outlet. This results in appropriate spreading of the mixture of fuel and fluid. The angle of the chamfered surface may depend on the size of the nozzle and the environment where the nozzle is used.

[0026] In embodiments of the first aspect, the mixing chamber has a mainly cylindrical shape. The mixing chamber can also be defined as a swirling chamber, since the fuel entering the mixing chamber gets a swirling motion through the chamber, mixing with the atomizing fluid when travelling through the mixing chamber before reaching the outlet. The shape being substantially cylindrical enhances the swirling effect of the fuel reaching the mixing chamber from the pre-filling chamber, so there is efficient mixture of fuel and fluid.

[0027] The shape of the mixing chamber can also be a cylinder with one end being a truncated cone. The end with the truncated cone is preferably the end of the mixing chamber connected to the outlet, where the cone has its smaller diameter.

[0028] The cylindrical shape of the mixing chamber has a longitudinal extension. The axis defining the longitudinal extension may be parallel to a normal of the chamfered surface of the first end of the nozzle. The longitudinal extension of the mixing chamber may also be aligned with the longitudinal extension of the outlet and with the longitudinal extension of the fluid channel. In embodiments of the first aspect, the pre-filling chamber is arranged in a radial plane between the fluid compartment and the contour surface and being arranged in an axial plane between the fuel compartments and the first end. Thereby the fuels have a short path to arrive at the pre-filling chamber from the fuel compartments. The location is also space efficient.

[0029] In embodiments of the first aspect, the fuel atomizing nozzle comprising at least three mixing chambers and three outlets. This ensures adequate spraying distribution. The number of mixing chambers and outlets associated thereto can vary, normally depending on the size of the nozzle. As an example, a larger nozzle normally has a larger number of mixing chambers and outlets associated thereto. Typically, the number of mixing chambers and outlets associated thereto could also be four, five or six, or even more like seven, eight, nine or ten. The number of pre-filling channels is at least one associated with each mixing chamber, so that each mixing chamber is connected with the pre-filling chamber via at least one pre-filling channel.

[0030] In embodiments of the first aspect, the fluid compartment has a mainly cylindrical shape and a longitudinal extension being closer to the first end than the fuel compartments. Thereby the connection to the mixing chamber can be easily established. The fluid compartment is symmetrically arranged around the longitudinal axis, i.e. centrally within the nozzle such that the longitudinal axis passes through the compartment in the middle so that the radial extension in the radial plane of the compartment starting in the longitudinal axis is the same in each direction.

[0031] In embodiments of the first aspect, the number of first and second fuel channels is at least three for each first and a second fuel channel, respectively. Having at least three first fuel channels and at least three second fuel channels connecting the upper part of the first and the second fuel compartment, respectively with the pre-filling chamber ensures sufficient fuel flow. The fuel channels may be spread out evenly along the ring-shaped fuel compartments and the ring-shaped pre-filling chamber. The number of fuel channels for each respective compartment could also be a larger number, such as four, five, six, seven, eight, nine or ten. Every second fuel channel is preferably a first fuel channel, so that a first fuel channel is followed by a second fuel channel.

[0032] In embodiments of the first aspect, the cross sectional shape of the fuel channels is rectangular. By this shape the channels could be maximized from a volume perspective, without space constraint. The cross section of a fuel channel is a plane that is normal to the longitudinal extension of the channel. The channels could also have any other cross sectional shape like circular, oval, cross section of a teardrop or cross section of a cone. The fuel channels may connect to the fuel compartments at the top end of the fuel compartments and the size of the cross sectional shape of the fuel channels in comparison to the radial extension of the fuel compartments may be large enough to minimize backpressure.

[0033] The extension of the fuel channels within the nozzle is both in the radial and axial plane, wherein the first fuel channel connects the first fuel compartment with the prefilling chamber and the second fuel channel connects the second fuel compartment with the pre-filling chamber. The connection is preferably from the upper end of each fuel compartment and the lower end of the pre-filling chamber.

[0034] In embodiments of the first aspect, the size of the cross sectional shape of the fluid channel varies along its length. The cross section of the fluid channel is a plane that is normal to the longitudinal extension of the channel. The cross sectional shape could be largest at each end and smallest at the midpart of its length, which is normally referred to as a venturi shape. Such a shape gives a good pressure recovery for the compressed fluid. The midpart of the length of the fluid channel is anywhere along its length that is not any of the endpoints connecting to the fluid compartment and the mixing chamber. The fluid channel is preferably connected to the middle part or upper end of the fluid compartment and the lower end of the mixing chamber. This means that the channel extends in both the radial and the axial plane. The number of fluid channels is at least three. The number of fluid channels connecting the fluid compartment with the mixing chamber might also be four, five, six, seven, eight, nine or ten.

[0035] In embodiments of the first aspect, the pre-filling channel connects to the mixing chamber at its side, and the fluid channel and the pre-filling channel are substantially perpendicular to each other. This is advantageous for a good mixture of the fluid with the fuel since the fuel entering the mixing chamber from the side enhances the swirling motion. A circular swirling motion of the fuel interacts efficiently with the fluid in order for the two substances to become a good mixture.

[0036] As a second aspect of the invention, there is provided a method of atomizing at least one fuel by the use of a fuel atomizing nozzle, wherein the method comprises the steps of leading a first fuel from a first fuel compartment by a first fuel channel to a prefilling chamber, leading the fuel from the pre-filling chamber by a pre-filling channel further to a mixing chamber, leading a fluid from a fluid compartment by a fluid channel to the mixing chamber, mixing the fuel and the fluid in the mixing chamber, and letting the mixture of the fuel and the fluid out through at least one outlet being connected to the mixing chamber.

[0037] This aspect may generally present the same or corresponding advantages as the former aspect. Effects and features of this second aspect are largely analogous to those described above in connection with the first aspect. Embodiments mentioned in relation to the first aspect are largely compatible with the second aspect.

[0038] The fuel and the fluid are led from respective compartment by pressure since the fuel and the fluid are pressurized. The fuel can be in liquid form.

[0039] In embodiments of the second aspect, there is provided a method of atomizing at least two fuels, wherein the method comprises the steps of leading a first fuel from a first fuel compartment by a first fuel channel to a pre-filling chamber, leading a second fuel from a second fuel compartment by a second fuel channel to the pre-filling chamber, leading the first fuel and the second fuel from the pre-filling chamber by a pre-filling channel further to a mixing chamber, leading a fluid from a fluid compartment by a fluid channel to the mixing chamber, mixing the at least two fuels and the fluid in the mixing chamber, and letting the mixture of the at least two fuels and the fluid out through at least one outlet being connected to the mixing chamber.

[0040] The third aspect is reliable to handle two fuels that are kept in two separate compartments, so that they are not mixed before reaching the pre-filling chamber. The two compartments are isolated from each other so that the two fuels are strictly kept apart. The fuels can be in liquid form.

[0041] As a third aspect of the invention, there is provided a system comprising a fuel atomizing nozzle, wherein the system comprises at least a first and a second fuel compartment for handling at least two fuels, which compartments are separated so that the first fuel is kept separate from the second fuel, and wherein the first and the second fuels are in liquid form.

[0042] This aspect may generally present the same or corresponding advantages as the former aspects. Effects and features of this third aspect are largely analogous to those described above in connection with the first and the second aspect. Embodiments mentioned in relation to the former aspects are largely compatible with the third aspect.

[0043] The system handling at least two fuels may follow the method of the second aspect of the invention.

[0044] The fuels may be oil, methanol, ammonia, biofuel or any other type of liquid fuel.

[0045] The first and the second fuel compartments can each contain a separate fuel. The design ensures that the fuels in the compartments are not in contact with each other. Further embodiments may comprise a third and a fourth fuel compartment that could comprise a third and a fourth fuel being separately held in each respective compartment.

[0046] Brief description of the Drawings

[0047] Figure 1A shows a cross sectional drawing of an atomizing nozzle.

[0048] Figure 1 B shows an enlargement from figure 1 A of a mixing chamber with an outlet.

[0049] Figure 2 shows a cross section taken in a perspective view of an atomizing nozzle.

[0050] Figure 3A shows a flow chart of the method of atomizing at least one fuel.

[0051] Figure 3B shows a flow chart of the method of atomizing at least two fuels.

[0052] Detailed Description

[0053] The fuel atomizing nozzle according to the present disclosure will be further illustrated by the following description with reference to the accompanying drawings.

[0054] Fig. 1A discloses a cross sectional view of an atomizing nozzle 1. The nozzle 1 has a mainly cylindrical shape defined in a longitudinal direction by a longitudinal axis X. The nozzle has a first end 11 and a second end 12, which ends 11 , 12 are located at different ends of the longitudinal axis X. The outer rounded surface of the nozzle 1 is defined by a contour surface 16. The nozzle 1 may have the same diameter throughout the entire length, or it may have a somewhat smaller diameter towards the first end 11. The transition to the smaller diameter may be stepwise as disclosed in the figure. Such a design helps the nozzle 1 to be securely arranged in the burner (not shown here).

[0055] In the centre of the nozzle, along the longitudinal axis X is a fluid compartment 14 located. This compartment is intended to contain an atomizing fluid that can be air or steam. The compartment 14 has a cylindrical shape at the second end 12. The fluid compartment 14 extends towards the first end 11 of the nozzle, at which end the compartment 14 has a conical shape. A plurality of fluid channels 24 connect to the fluid compartment 14 at the conical part of the compartment 14. Each channel 24 connects the fluid compartment 14 with a mixing chamber 40.

[0056] A first and a second fuel compartment 15a, 15b are arranged outside of the fluid compartment 14. Both fuel compartments 15a, 15b have an annular shape, encircling the fluid compartment 14. Closest to the fluid compartment 14 is the first fuel compartment 15a located, which has the purpose to contain a first fuel. The second fuel compartment 15b, intended to contain a second fuel, is located between the first fuel compartment 15a and the rounded outer surface of the nozzle 1, i.e. the contour surface 16. Both fuel compartments 15a, 15b have a certain longitudinal extension being parallel with the longitudinal axis X. Both fuel compartments 15a, 15b have their base at the second end 12 and have a longitudinal extension being shorter than the longitudinal extension of the fluid compartment 14.

[0057] Respective first and second fuel channels 25a, 25b are connected to the first and the second fuel compartments 15a, 15b. The plurality of fuel channels 25a, 25b are connected to the top ends of the fuel compartments 15a, 15b, i.e. the end of each compartment 15a, 15b that is directed toward the first end 11 of the nozzle 1.

[0058] A pre-filling chamber 35 is located in the nozzle toward the first end 11. The prefilling chamber 35 is annularly shaped and is arranged above the fuel compartments 15a, 15b, i.e. closer to the first end 11 than the fuel compartments 15a, 15b. From a radial perspective the pre-filling chamber 35 is located between the first and the second fuel compartments 15a, 15b, so that the pre-filling chamber 35 is arranged radially outside of the first fuel compartment 15a and radially inside of the second fuel compartment 15b.

[0059] The pre-filling chamber 35 has a certain extension in the longitudinal direction and in the radial direction. In the illustrated embodiment the inner radial wall of the chamber 35 is chamfered towards the outer radial wall of the chamber 35, so that the radial extension of the pre-filling chamber 35 is smaller toward the first end 11 of the nozzle. The fuel channels 25a, 25b are connected to the bottom end (i.e. towards the second end 12) of the pre-filling chamber 35.

[0060] The plurality of first fuel channels 25a connect the first fuel compartment 15a with the pre-filling chamber 35. The plurality of second fuel channels 25b connect the second fuel compartment 15b with the pre-filling chamber 35. The first and the second fuel channels 25a, 25b are spread out along the circular shape of the fuel compartments 15a, 15b. Preferably, the first fuel channel 25a is followed by a second fuel channel 25b, which then is followed by a first fuel channel 25a, etc., following the ring shape of the pre-filling chamber 35 and the fuel compartments 15a, 15b.

[0061] The mixing chambers 40 are located close to the first end 11 of the nozzle. So, the mixing chambers 40 are located above the pre-filling chamber 35. And the mixing chambers 40 have a location being radially inwards of the pre-filling chamber 35. A plurality of pre-filling channels 45 connect the pre-filling chamber 35 with the mixing chambers 40. The pre-filling channels 45 may be shaped like a tear drop in a cross section or they could have a circular cross section and have an outlet end connecting to the mixing chambers having a cross section deviating from a circular shape, i.e. being tear dropped shaped.

[0062] The mixing chambers 40 are located in connection to outlets 17. One mixing chamber 40 is associated with one outlet 17. The outlets 17 are arranged at the first end 11 of the nozzle 1. The first end has a chamfered surface 13. The outlets 17 are arranged in the chamfered surface 13.

[0063] The mixing chamber 40 has a mainly cylindrical shape with a smaller diameter at the end connecting to an outlet 17, so that part of the mixing chamber 40 is conically shaped.

[0064] Fig. 1B discloses an enlargement of the area around the outlet 17 and mixing chamber 40 of the atomizing nozzle 1 in figure 1A.

[0065] A fluid channel 24 and a pre-filling channel 45 are connected to each mixing chamber 40. The fluid channel 24 is aligned with the longitudinal direction of the cylindrical mixing chamber 40 and the fluid channel 24 connects to the mixing chamber 40 at the opposite end to the outlet 17. The pre-filling channel 45 connects to the mixing chamber 40 at its side, i.e. at the mantle of the cylinder and towards the end of the mixing chamber 40 where the fluid channel 24 is connected. The fluid channel 24 and the pre-filling channel 45 are perpendicular to each other. The longitudinal direction of the mixing chamber 40 is a normal to the adjacent chamfered surface 13. The pre-filling channel 45 may also deviate from being perpendicular to the fluid channel 24 and the mixing chamber 40. The deviation might be a few degrees.

[0066] The arrows illustrate the flow of the fluid (black arrow) and the flows of the first and the second fuel (patterned arrows), respectively, these arrows are seen e.g. in figure 1A and 1B. The atomizing fluid passes through the fluid channel 24 and enters the mixing chamber 40 at the bottom end. The first and / or the second fuel arrives from the pre-filling channel 45 to the mixing chamber 40 via the side wall. In the mixing chamber 40 the fluid mixes with the first and / or second fuel. The mixing is intensified by a swirling motion.

[0067] The black arrow represents the fluid coming from the fluid compartment 14. While passing through the mixing chamber 40 the fluid mixes with the fuel, so further into the mixing chamber 40 the black arrow represents a mixture of fluid and fuel.

[0068] Fig. 2 shows a perspective view of the fuel atomizing nozzle 1. The perspective view has a cross sectional cut. Thereby the compartments and their shape inside the nozzle can be seen. The flows of the first and the second fuel, as well as the flow of the fluid are represented with one arrow for each substance. The illustrated embodiment has five outlets 17 and five mixing chambers 40, and five fluid channels 24 are connecting to the mixing chambers 40.

[0069] The fluid channels 24 have a mainly cylindrical shape with an indent on the middle section, which normally is referred to as a venturi pipe. This channel 24 can also be described as two truncated cones being aligned with the smaller diameter of each connecting to each other.

[0070] In the represented embodiment there is a first and a second fuel compartment 15a, 15b where the first and the second fuel is represented by arrows being led from each respective compartment 15a, 15b via the respective fuel channel 25a, 25b to the pre-filling chamber 35 and then via the pre-filling channel 45 (shown in figure 1B) to the mixing chamber 40 and out through the outlet 17.

[0071] Typically, the atomizing fluid is saturated steam that is led to the mixing chamber 40 (from the fluid compartment 14) where it is mixed with one or two fuels, so that the mixture being discharged through the outlet 17 is a fine spray. As an example, the first fuel could be biodiesel, and the second fuel could be diesel. Biodiesel is used as a first choice, and if needed diesel could be added to mix with the biodiesel in the pre-filling chamber 35 before reaching the mixing chamber 40 and mixing with the steam.

[0072] The nozzle 1 is made in one part, so the body 10 is manufactured as a solid part. Preferably, the nozzle 1 is formed by additive manufacturing. This means that in the present embodiment the nozzle 1 only consists of one part, however, it is also feasible that the nozzle 1 comprises two or more parts put together in order to have a functioning nozzle 1.

[0073] The method 100 of atomizing at least one fuel according to the present invention is further illustrated by the flow chart presented in figure 3A. The method comprises the steps of first leading 101a a first fuel from a first fuel compartment 15a by a first fuel channel 25a to a pre-filling chamber 35, then leading 102a the first fuel from the prefilling chamber 35 by a pre-filling channel 45 further to a mixing chamber 40. Leading 103 a fluid from a fluid compartment 14 by a fluid channel 24 to the mixing chamber 40 is done at the same time as the first fuel is led to the mixing chamber. The mixing 104a of the fuel and the fluid is done in the mixing chamber 40, before letting 105 the mixture of the fuel and the fluid out through at least one outlet 17 being connected to the mixing chamber 40.

[0074] The method 100 of atomizing at least two fuels according to the present invention is further illustrated by the flow chart presented in figure 3B. The method comprises the steps of leading 101a a first fuel from a first fuel compartment 15a by a first fuel channel 25a to a pre-filling chamber 35, and leading 101b a second fuel from a second fuel compartment 15b by a second fuel channel 25b to the pre-filling chamber 35. The first and second fuels can be led simultaneously to the pre-filling chamber or one after the other. Leading 102b the first fuel and the second fuel from the pre-filling chamber 35 by a pre-filling channel 45 further to a mixing chamber 40 is then done. Leading 103 a fluid from a fluid compartment 14 by a fluid channel 24 to the mixing chamber 40 is done at the same time as the first and second fuels are led to the mixing chamber. The mixing 104b of the at least two fuels and the fluid is done in the mixing chamber 40, before letting 105 the mixture of the at least two fuels and the fluid out through at least one outlet 17 being connected to the mixing chamber 40.

[0075] The invention is not limited to the embodiment disclosed but may be varied and modified within the scope of the claims set out below. The invention is not limited to the type of fuel atomizing nozzle as shown in the Figures.

[0076] REFERENCE LIST

[0077] 1: nozzle

[0078] 10: nozzle body

[0079] 11 : first end of nozzle

[0080] 12: second end of nozzle

[0081] 13: chamfered surface

[0082] 14: fluid compartment

[0083] 15a: first fuel compartment

[0084] 15b: second fuel compartment 16: contour surface 17: outlet

[0085] 24: fluid channel

[0086] 25a: first fuel channel

[0087] 25b: second fuel channel

[0088] 35: pre-filling chamber

[0089] 40: mixing chamber

[0090] 45: pre-filling channel

[0091] X: longitudinal direction 100: method 101a: leading first fuel to pre-filling chamber

[0092] 101a: leading second fuel to pre-filling chamber

[0093] 102a: leading first fuel to mixing chamber

[0094] 102b: leading first and second fuel to mixing chamber 103: leading fluid to mixing chamber

[0095] 104a: mixing fuel and fluid

[0096] 104b: mixing fuels and fluid

[0097] 105: letting mixture out

Claims

CLAIMS1. A fuel atomizing nozzle (1) for handling at least two fuels and an atomizing fluid, the fuel atomizing nozzle (1) comprising a solid body (10) having a mainly cylindrical shape around a longitudinal axis (X) defining a first end (11), a second end (12) and a contour surface (16) extending there between connecting the two ends (11 , 12), wherein the first end (11) comprises at least one outlet (17), wherein the fuel atomizing nozzle (1) further comprises a fluid compartment (14) being arranged centrally around the longitudinal axis (X) in the solid body (10), at least a first and a second fuel compartment (15a, 15b) being arranged in a radial plane between the fluid compartment (14) and the contour surface (16), the fuel compartments (15a, 15b) having an annular shape, the at least first and second fuel compartments (15a, 15b) being connected to a pre-filling chamber (35) by at least a first and a second fuel channel (25a, 25b), respectively, at least one mixing chamber (40) being arranged between the fluid compartment (14) and the at least one outlet (17), and a fluid channel (24) connecting the at least one mixing chamber (40) and the fluid compartment (14), wherein the pre-filling chamber (35) has an annular shape, and the pre-filling chamber (35) is connected via a pre-filling channel (45) to the at least one mixing chamber (40).

2. A fuel atomizing nozzle (1) according to claim 1 , wherein the body (10) is one single solid part.

3. A fuel atomizing nozzle (1) according to claim 1 or 2, wherein one outlet (17) is connected to one mixing chamber (40), respectively.

4. A fuel atomizing nozzle (1) according to any previous claim, wherein the first end (11) comprises at least one chamfered surface (13) comprising the at least one outlet (17).

5. A fuel atomizing nozzle (1) according to any previous claim, wherein the mixing chamber (40) has a mainly cylindrical shape.

6. A fuel atomizing nozzle (1) according to any previous claim, wherein the pre-filling chamber (35) is arranged in a radial plane between the fluid compartment (14) and the contour surface (16) and being arranged in an axial plane between the fuel compartments (15a, 15b) and the first end (11).

7. A fuel atomizing nozzle (1) according to any previous claim, comprising at least three mixing chambers (40) and three outlets (17).

8. A fuel atomizing nozzle (1) according to any previous claim, wherein the fluid compartment (14) has a mainly cylindrical shape and a longitudinal extension being closer to the first end (11) than the fuel compartments (15a, 15b).

9. A fuel atomizing nozzle (1) according to any previous claim, wherein the number of first and second fuel channels (25a, 25b) is at least three for each first and a second fuel channel (25a, 25b), respectively.

10. A fuel atomizing nozzle (1) according to any previous claim, wherein the cross sectional shape of the fuel channels (25a, 25b) is rectangular.

11. A fuel atomizing nozzle (1) according to any previous claim, wherein the size of the cross sectional shape of the fluid channel (24) varies along its length.

12. A fuel atomizing nozzle (1) according to any previous claim, wherein the pre-filling channel (45) connects to the mixing chamber (40) at its side, and the fluid channel (24) and the pre-filling channel (45) are perpendicular to each other.

13. Method (100) of atomizing at least one fuel by the use of a fuel atomizing nozzle (1) according to claims 1 to 12, wherein the method comprises the steps of- leading (101a) a first fuel from a first fuel compartment (15a) by a first fuel channel (25a) to a pre-filling chamber (35),- leading (102a) the fuel from the pre-filling chamber (35) by a pre-filling channel (45) further to a mixing chamber (40),16- leading (103) a fluid from a fluid compartment (14) by a fluid channel (24) to the mixing chamber (40),- mixing (104a) the fuel and the fluid in the mixing chamber (40), and- letting (105) the mixture of the fuel and the fluid out through at least one outlet (17) being connected to the mixing chamber (40).

14. Method (100) of atomizing at least two fuels according to claim 13, wherein the method comprises the steps of- leading (101a) a first fuel from a first fuel compartment (15a) by a first fuel channel (25a) to a pre-filling chamber (35),- leading (101b) a second fuel from a second fuel compartment (15b) by a second fuel channel (25b) to the pre-filling chamber (35),- leading (102b) the first fuel and the second fuel from the pre-filling chamber (35) by a pre-filling channel (45) further to a mixing chamber (40),- leading (103) a fluid from a fluid compartment (14) by a fluid channel (24) to the mixing chamber (40),- mixing (104b) the at least two fuels and the fluid in the mixing chamber (40), and- letting (105) the mixture of the at least two fuels and the fluid out through at least one outlet (17) being connected to the mixing chamber (40).

15. A system comprising a fuel atomizing nozzle (1) according to claims 1 to 12, wherein the system comprises at least a first and a second fuel compartment (15a, 15b) for handling at least two fuels, which compartments are separated so that the first fuel is kept separate from the second fuel, and wherein the first and the second fuels are in liquid form.

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