EP4033152A1

EP4033152A1 - A cooking appliance with an improved exhaust performance

Info

Publication number: EP4033152A1
Application number: EP22152964.7A
Authority: EP
Inventors: Serkan CIGAL; Serkan Emre Erfidan; Sezer Isbilen; Ahmet Ilyas Kodal; Efe Can Yilmaz
Original assignee: BSH Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2021-01-26
Filing date: 2022-01-24
Publication date: 2022-07-27
Anticipated expiration: 2042-01-24
Also published as: TR202101108A1; EP4033152B1

Abstract

The present invention proposes a cooking appliance (100) having a cooking cavity (10) defined within a top wall (11), a bottom wall (12), a rear wall (13), and opposing side walls (14) comprising, a burner (20) having a cylindrical casing (21) and at least one wing unit (22) radiating heat within said cooking cavity (10), an exhaust channel (30) having an inlet (31) which is in fluid communication with the cooking cavity (10) and an outlet (32) which is in fluid communication with an exterior of the cooking appliance (100) wherein the exhaust channel (30) is configured to allow fresh air to enter into the cooking cavity (10) and to allow exhaust gases to vent therefrom and the inlet (31) which is disposed on the top wall to be aligned above a middle portion (23) of the burner (20) so as to provide an airflow region (50) provided between the wing units (22) and the top wall (11) of the cooking cavity (10) wherein the inlet (31) is positioned at a predetermined location such that the inlet (31) is enclosed in an orthogonal projection of the burner (27) on a plane containing the inlet (31) wherein a cross section (312) area of the inlet (31) is sized to be less than a predetermined value.

Description

Technical Field of the Invention

The present invention relates to a cooking appliance with an improved exhaust system for providing effective burning process and for reducing the pollutant emission according to preamble of claim 1.

Background of the Invention

Several cooking appliance that includes isolated compartments suitable for receiving a food item for heating attains the required energy by burning gases so as to heat a cooking cavity. Realizing an efficient combustion process, therefore, requires that the heat needed for cooking food is produced effectively. This combustion process, in addition to the need for producing the heat for cooking, must be carried out in a way that reduces the emissions of pollutants and enables energy to be used more environment friendly. It is surely beyond doubt that the combustion process occurs as a consequence of the exothermic chemical reaction of hydrogen and carbon atoms in oxygen-containing fuels. Nevertheless, if there is not enough oxygen in the cooking appliance, carbon monoxide is created due to a lack of oxygen and the gas is not completely burnt. Accordingly, said partially burned fuel increases the emissions of pollutants by inducing a decline in combustion efficiency. Hence efficient combustion process requires continuous supply of fresh outside air and also a regular flow throughout the cooking cavity.
In addition to the continuous supply of fresh air, the waste gas and/or exhaust gas produced during the burning process must be removed therefrom so as to retain the combustion process. Different techniques are known in the art for exhausting fumes and gases generated during cooking from the cooking chamber. A commonly used method for the safe and efficient disposal of combustion gasses is based on use of exhaust ducts connected to chimneys.
It is desirable therefore to have a low cost and easily applicable system which can provide an effective burning process, remove exhaust gasses from the cooking cavity and reduce the pollutant emission.

Summary of the Invention

It is an object of the present invention to provide a further development with an advantage over the state of the art, hence the present invention provides a cooking appliance which is able to increase exhausting performance and to raise gas combustion efficiency so as to achieve high energy output in an easy, economic and convenient manner.
The embodiments of the present disclosure address one or more of the foregoing or other problems in the art. Any implementation of the present disclosure is concerned in particular with enhanced cooking equipment, its components and/or sub-components, and its apparatus.
The present invention proposes a cooking appliance having a cooking cavity defining within a top wall, a bottom wall, a rear wall, and opposing side walls comprising, an oven burner having a cylindrical casing and at least one wing unit radiating heat downwardly, an exhaust channel having an inlet which is in fluid communication with an interior of the cooking cavity and an outlet which is in fluid communication with an exterior of the cooking appliance wherein the exhaust channel is configured to allow fresh air to enter the cooking cavity and to allow exhaust gases to vent therefrom. Additionally, the inlet is disposed on the top wall and arranged to be aligned above the oven burner to provide an airflow region provided between the wing units and the top wall of the cooking cavity. Hence, a cooking appliance and an exhaust channel of the same which maintains the desired air/fuel ratio and enhances combustion efficiency are provided.
In a possible embodiment of the invention, the inlet is arranged concentrically with the oven burner. In another embodiment of the invention the inlet is configured to be enclosed in a centred manner in the orthogonal projection of the burner on a plane containing the inlet. The orientation of the inlet provides a swirl flow of exhaust gases thereby achieving an efficient combustion process and reduced emissions.
In a possible embodiment of the invention, the center of the cross section of the inlet is arranged over the middle portion bisecting or nearly bisecting the width of the burner.
Said orientation of the inlet enables the exhaust gases to follow an exhaust gas path formed by the exhaust channel. In a possible embodiment of the invention, the center of cross section of the inlet is arranged over the middle portion bisecting or nearly bisecting of the length of the burner. Hence, the waste gas and/or exhaust gas produced in the burning process is removed therefrom to retain the combustion process.
In a possible embodiment, the inlet has a cross sectional area which is sized to be less than a predetermined value which corresponds to the sum of a first cross section area of the airflow region, a second cross section area of the airflow region, twenty percent of a third cross section area of the airflow region and twenty percent of the fourth cross section area of the airflow region. In that, the first cross section area is the cross section of the airflow region at the lateral left side of a left wing unit, the second cross section area is the vertical cross section of the airflow region at the lateral right side of a right wing unit, the third cross section area is the vertical cross section of the airflow region which faces the rear wall of the cooking cavity and taken parallel to thereto and the fourth cross section area is the vertical cross section of a front side of the airflow region wherein said front side is a distal side to the rear wall of the cooking cavity.
In another possible embodiment, at least one edge each of the first cross section and the second cross section of the airflow region is formed by a longitudinal axis of the burner, and at least one edge each of the third cross section and the fourth cross section of the airflow region is formed by a transverse axis of the burner. Since the size of the cross sectional area of the inlet affects the flow rate of the waste gas, the fact that the cross sectional area is lower than said predetermined value prevents the heat needed for the heating of the cooking cavity from being transferred to the exterior of the cooking appliance. The airflow region in which the waste gas generated as a consequence of combustion accumulates is taken into account and hence the airflow region is sized and shaped to minimize emission and ensure adequate combustion efficiency. Alteration of the dimensions of the oven burner, therefore, leads to a change in the pollutant emissions generated from fuel combustion and energy efficiency of the cooking appliance.
In a possible embodiment of the invention, the inlet has a predetermined cross sectional area wherein said area is sized to be larger than a predetermined value depending on a power of the oven burner, a burner coefficient and a safety factor of the oven burner.
Said dimensioning and tolerancing of cross sectional area confine and control heating volume for minimizing the generation of carbon monoxide (CO) and maximizing the production of radiant heat.
In a possible embodiment of the invention, the cross section of the inlet is formed in a substantially rectangular shape with its minor dimension ranging from 10 % to 80 %, optionally 15 % to 35 %, of its major dimension. Hence cross section of the inlet is sized with a tolerance circle, accordingly, advancement in burning efficiency and reduction in emission are provided.
In accordance with another possible embodiment of the invention, said cross section of the inlet has a dimension of 20 mm x 70 mm, thereby ensuring that the temperature of a door surface of a cooking appliance remains within the standard limits without using a further ventilation system. If the dimensions of the inlet are not sufficiently large, exhaust performance would decrease and an effective combustion process canot be obtained due to the insufficient (???) fresh air.
In a possible embodiment, the inlet has a cross sectional area in a range of from 1365 mm² to 1472 mm². Said cross section is therefore sized in such a way that the pollutant emission is minimized and the heat generated by the oven burner is effectively distributed in the cooking cavity.
The exhaust channel is formed in substantially Z-shaped in accordance with a possible embodiment of the invention. Various connection means, such as plug and screws, may be used for associating the exhaust channel with a cooktop and cooking cavity of the cooking appliance In light of the foregoing, therefore, the basic design of the exhaust channel achieves the uncomplicated and cost-effective manufacture and assembly thereof.
In a possible embodiment of the invention, the cooking appliance is an oven, a grill or a gas cooker.
In this context, with the indications "front", "upper", "below", "top", "bottom" etc. the positions and orientations given for intended use and intended arrangement of the cooking device and for a user then standing in front of the cooking device in viewing in the direction of the device are indicated.

Brief description of the figures

The accompanying drawings are given solely for the purpose of exemplifying the invention whose advantages over prior art were outlined above and will be explained in detail hereinafter:

Fig. 1 illustrates a frontal perspective view of the cooking appliance comprising the exhaust channel in accordance with a possible embodiment of the present invention.
Fig. 2 illustrates a partly frontal perspective view of the cooking appliance comprising an aperture arranged on a cooktop in accordance with a possible embodiment of the present invention.
Fig. 3 illustrates a partial top perspective view of the cooking appliance comprising the outlet of the exhaust channel in accordance with a possible embodiment of the present invention.
Fig. 4 illustrates a partial perspective cross sectional view of the cooking appliance comprising the outlet, the inlet, and an air duct of the exhaust channel in accordance with a possible embodiment of the present invention.
Fig. 5 illustrates a frontal view of a cooking cavity comprising the top wall, the bottom wall, the rear wall, sides wall, and the inlet housing in accordance with a possible embodiment of the present invention.
Fig. 6 illustrates a side view of the exhaust channel which depicts the montage thereof in a cooking appliance in accordance with a possible embodiment of the present invention.
Fig. 7 illustrates a perspective view of the exhaust channel having the inlet, the outlet, and the air duct according in accordance with a possible embodiment of the present invention.
Fig. 8 illustrates an exploded view of the exhaust channel depicting in Fig. 7 in accordance with a possible embodiment of the present invention.
Fig. 9 illustrates a partly upper view of the cooking devices without a cooktop in accordance with a possible embodiment of the present invention.
Fig. 10 illustrates a perspective view of an burner comprising the cylindrical casing, the wing unit, the longitudinal axis, and the transverse axis in accordance with a possible embodiment of the present invention.
Fig. 11 illustrates a frontal view of the burner depicted in Fig.10 in accordance with a possible embodiment of the present invention.
Fig. 12 illustrates a side view of the burner depicted in Fig. 10 in accordance with a possible embodiment of the present invention.
Fig. 13 illustrates a partial frontal view of an airflow region arranged between the burner and the top wall in accordance with a possible embodiment of the present invention.
Fig. 14 illustrates a partial side view of the airflow region arranged between the burner and the top wall in accordance with a possible embodiment of the present invention.
Fig. 15 illustrates a partly schematic view of the airflow region comprising a first, a second, a third, and a fourth cross section depicted in Fig.13 and Fig.14 in accordance with a possible embodiment of the present invention.
Fig. 16 illustrates a schematic view representing a middle portion of the burner in accordance with a possible embodiment of the present invention
Fig. 17 illustrates a schematic view depicting the burner and the cross section in accordance with a possible embodiment of the present invention.
Fig. 18 illustrates a schematic view representing the position of the burner and a cross section of the inlet relative to each other in accordance with a possible embodiment of the present invention.
Fig. 19 illustrates a schematic view representing the middle portion of the burner in accordance with a possible embodiment of the present invention.
Fig. 20 comparatively illustrates the relationship between the cross sectional area of the inlet and the amount of carbon monoxide (C0) generated in the oven cavity in accordance with a possible embodiment of the present invention.

Detailed description of the figures

Hereinafter, various possible embodiments of the present invention will be described in detail with reference to the accompanying drawings which are given solely for the purpose of exemplifying embodiments according to the present invention. The list of reference numerals used in the appended drawings is provided at the end of this section.
The present invention relates to a cooking appliance (100), as illustrated in Fig. 1, with an improved exhaust channel (30) conformation for providing an effective cooking performance in a more safe and cost-effective way.
Referring to Fig. 2 and Fig. 3, said cooking appliance (100) generally comprises a cooktop (90) and an aperture (91) associated with an outlet (32) of an exhaust channel (30).
As illustrated in Fig. 4 to Fig. 6, said cooking appliance (100) having a cooking cavity (10) defined within a top wall (11), a bottom wall (12), a rear wall (13), an inlet housing (15) and opposing sidewalls (14) comprises the exhaust channel (30) having an inlet (31) which is in fluid communication with an interior of the cooking cavity (10) and the outlet (32) which is in fluid communication with an exterior of the cooking appliance (100) wherein the exhaust channel (30) is configured to allow fresh air to enter into the cooking cavity (10) and to allow exhaust gases to vent therefrom. As can be seen in Fig. 7 and Fig. 8, the exhaust channel (30) further comprises an air duct (33) having a first piece (34) and a second piece (35). Since the object of the invention is to eliminate the unnecessary cost in the manufacturing process and to provide a user-friendly design, various connection means like plugs and screws can be chosen to provide a connection between the exhaust channel (30) and the cooking appliance (100). Additionally, referring again to Fig. 8, the exhaust channel (30) is formed of a substantially Z-shaped geometry, the uncomplicated, cost-effective manufacture and assembly thereof are provided by means of the basic design of the exhaust channel (30).
Fig. 10 to Fig. 12 illustrates a burner (20) comprising a cylindrical casing (21) and at least one wing unit (22) radiating heat within said cooking cavity (10). Furthermore said cylindrical casing (21) has a plurality of flame ports extending through a top portion thereof. Said wing unit (22) extends outwardly from said cylindrical casing (21) wherein said wing unit (22) is configured to direct and to distribute the heated air the underside of thereof. Moreover said wing unit further comprises a right wing unit (221) and a left wing unit (222).
Referring to Fig. 6 and Fig.9, the inlet (31) which is disposed on the top wall (11) is arranged to be aligned above the burner (20) to provide an airflow region (50) arranged between the wing units (22) and the top wall (11) of the cooking cavity (10).
Various experiments have been conducted to establish the proper position of the inlet (31). Considering the airflow region (50) where the waste gas generated by combustion accumulates, the relationship between the location of the inlet (31) and the sizes of the burner (20) are determined. In that, depending on the width and the length of the burner (20), the position of the inlet (31) is conveniently established. To explain in more detail, the position of the inlet (31) arranged on the top wall (11) is ascertained by taking a parallel and/or orthogonal projection (313) of a cross section (312) of the inlet (31) on a plane where the burner (20) is located as depicted in Fig. 17. Since the experimental studies establish that lower emission levels are achieved when the distance and/or volume between the burner (20) or wing unit (22) and the top wall (11) is increased, a new position of the burner (20) in the cooking cavity (10) is determined in accordance with this increased distance.
Fig. 10 to Fig. 12 illustrate the burner (20) comprising the cylindrical casing (21) and at least one wing unit (22) radiating heat within the said cooking cavity (10). Furthermore said cylindrical casing (21) has a plurality of flame ports extending through a top portion thereof. Said wing unit (22) extends outwardly from said cylindrical casing (21) wherein said wing unit (22) is configured to direct and distribute the heated air downwards.
Referring to Fig. 16, the inlet (31) is positioned over a middle portion (23) of the burner (20). In accordance with a possible embodiment of the present invention, the inlet (31) is positioned such that the inlet (31) is enclosed in an orthogonal projection of the burner (27) on a plane containing the inlet (31) as again depicted in Fig. 9 .
Referring to Fig. 17, said cross section (312) of the inlet (31) has a width (W3) of 20 mm and a length (L3) of 70 mm.
A schematic view representing the orthogonal projection of the burner (27) on a plane containing the inlet (31) is illustrated in Fig. 18 wherein the inlet (31) is configured to be enclosed in a centered manner in the orthogonal projection of the burner (27) on a plane containing the inlet (31). The center (311) of the cross section (312) of the inlet (31) is arranged over the middle portion (23) bisecting or nearly bisecting the width of the burner (20).
In a possible embodiment, the center (311) of the cross section (312) of the inlet (31) is arranged over the middle portion (23) bisecting or nearly bisecting the length of the burner (20).
As illustrated in Fig. 18, a first distance (D1) between the center (311) of the orthogonal projection (313) of the inlet (31) and a longitudinal edge of the burner (L1) corresponds to half the width of the burner (20).
In another possible embodiment, the first distance (D1) between the center (311) of the orthogonal projection (313) of the inlet (31) and the longitudinal edge of the burner (L1) corresponds to slightly less than half the width of the burner (20). In a possible embodiment, the first distance (D1) between the center (311) of the orthogonal projection (313) of the inlet (31) and the longitudinal edge of the burner (L1) corresponds to slightly more than half the width of the burner (20).
Referring again to Fig.18, a second distance (D2) between the center (311) of the orthogonal projection (313) of the inlet (31) and a transverse edge of the burner (W1) corresponds to the half-length of the burner (20). In a possible embodiment said second distance (D2) corresponds to slightly less than the half-length (L1) of the burner (20). In another possible embodiment, said second distance (D2) corresponds to slightly more than the half-length of the burner (20).
As depicted in Fig. 19, said middle portion (23) in accordance with an exemplary embodiment comprises an intersection of second parts which are obtained in a situation where both a length in a longitudinal axis (25) and a width in a transverse axis (26) of the burner (20) are divided into three equal parts.
Fig. 13 and Fig. 14 illustrate the airflow region (50) arranged between the burner (20) and the top wall (11) wherein said airflow region (50) has a shape in the form of a pentagonal prism, or a rectangular pentagonal prism, or rectangular prism shape, or polygon prism.
The airflow region shown in Fig. 15 comprises a first cross section (51) and a second cross section (52) constituting a rectangular conformation whose at least one edge is formed by the longitudinal axis (25) and/or longitudinal edge of the burner (L1) and/or the wing unit (22), and a third cross section (53) and a fourth cross section (53) constituting a pentagon conformation whose at least one edge is formed by the transverse axis (26) and/or a transverse edge of the burner (W1).
An exemplary working embodiment in accordance with the invention is described below in detail. By giving the example, it is solely intended to provide a better understanding, demonstrate a proof-concept and to demonstrate compliance with the enablement requirement. On the other hand, by giving below specified parameter values, it is not intended to unduly limit the scope of the present invention to disclosed specific parameter values.
Turning now to the exemplary working embodiment, the burner (20) employed in the cooking appliance (100) had a width (i.e. a transverse edge (W1)) of 156 mm and a length (i.e. a longitudinal edge (L1)) of 240 mm. It has been discovered through experiments that the width and the length of the burner (20) are decisive when determining the ideal position of the airflow region (50) as mentioned above. According to the results obtained from a computer-based experimental run, the inlet (31) was positioned at the location where the waste gas formed is concentrated. The first distance (D1) between the center (311) of the orthogonal projection (313) of the inlet (31) and the longitudinal edge of the burner (L1) is calculated as 78 mm. Additionally, the second distance (D2) between the center (311) of the orthogonal projection (313) of the inlet (31) and the transverse edge of the burner (W1) is calculated as 120mm. These features are merely examples, which should not unduly limit the scope of the application. One ordinary skill in the art would recognize many variations, modifications, and alternatives.
First formula (I) is used to calculate the lowest cross sectional area "A" of the inlet (31) so as to remove exhaust gasses from the cooking cavity (10) and to provide effective exhaustion performance without using a ventilation system or a requirement to keep the door open. In the formulae, the power of burner (20) employed in the exemplary embodiment is denoted by "P", the burner (20) coefficient is denoted by "E", and the safety coefficient is denoted by "F", $A > 1000 \times P \times E \times F$
The power of burner (20) employed in the working example is 2,1 Kw, the burner (20) coefficient is 0,5 and the safety coefficient is 1,3. On the basis of the first formula (I), the inlet (31) is configured to have a cross sectional area to be greater than 1365 mm².
In order to the determine the maximum value of the cross sectional area of the inlet (31), a second formulation (II), a third formulation (III), a fourth formulation (IV), fifth formulation (V) and a sixth formulation (VI) have been developed as a result of analytical and modelling studies for ensuring energy efficiency of the cooking appliance (100). The following formulas can be employed, individually, for calculating the greatest cross sectional area "A" of the inlet (31), wherein the area of the first cross section (51) of the airflow region (50) to be employed in the exemplary embodiment is denoted by "S1", the area of the second cross section (52) of the airflow region (50) is denoted by "S2", the area of the third cross section (53) of the airflow region (50) is denoted by "S3", and the area of the fourth cross section (54) of the airflow region (50) is denoted by "S4", $A < [S 1 + S 2 + (0.2 \times S 3) + (0.2 \times S 4)]$
$A < 2 \times [(0.2 \times S 3) + S 1]$
$A < 2 \times [(0.2 \times S 3) + S2]$
$A < 2 \times [(0.2 \times S4) + S 1]$
$A < 2 \times [(0.2 \times S4) + S2]$
In accordance with said exemplary working embodiment, area "S1" of the first cross section (51) and the area " S2" of the second cross section (52) of the airflow region (50) are equal to 1920 mm². Moreover, the area "S3" of the third cross section (53) and the area " S4" of the fourth cross section (54) of the airflow region (50) are equal to 2156 mm² wherein "S1", "S2", "S3" and "S4" are calculated based on the dimensions of the burner (20) and the distance between the top wall (11) and the plane containing the burner (20). On the basis of the foregoing five formulas, the inlet (31) is configured to have a cross sectional area to be less than 4271 mm². By giving said example, it is not intended to unduly limit the scope of the present invention to disclosed specific parameter values. One ordinary skill in the art would recognize many variations, alternatives, and modifications.
In experimental studies, burners (20) employed in the exemplary embodiments have various parameters such as power of the burner (20) varying in between 1.5 kW and 3.5 kW, the burner (20) coefficient varying in between 0.5 and 1, and safety coefficient varying in between 1 and 2.
In some of these exemplary embodiments, the first cross section area "S1" and the second cross section area "S2" of the airflow region (50) were determined between 1200 mm² and 2520 mm², and the third cross section area "S3" and the fourth cross section area "S4"were determined in between 1540 mm² and 2460 mm².
As mentioned above, various experiments have been carried out to determine the relative position and cross sectional area of the inlet (31). A graph in Fig. 20 illustrates a few results derived from the experiments wherein the relationship between the cross sectional area of the inlet (31) and the amount of carbon monoxide (CO) is depicted. Referring again to Fig. 20; G30 represents Butane gas, G20 represents Methane gas, G21 represents a gas mixture comprising 13 % Propane gas in Methane gas, H represents higher Wobbe Index range, and L represents lower Wobbe Index range. Moreover the line with the triangle marker represents an arrangement that includes the inlet (31) where the cross sectional area is equal to 1260 mm², while the line with the circle marker represents an arrangement that includes the inlet (31) where the cross sectional area is equal to 1400 mm². The amount of carbon monoxide formed during the combustion process of an oven with a larger cross sectional area (i.e.1400 mm²), is significantly lower than the oven with a narrower cross sectional area (i.e.1260 mm²). As there is more air intake in the arrangement where the cross sectional area is greater and, hence, the combustion process takes place with a more uniform air mixture.
The cooking appliance (100) is not limited to the possible applications and working examples described above. Embodiments of the present disclosure solve one or more of the foregoing or other problems in the art with improved systems for effective exhaustion performance without using a ventilation system or a requirement to keep the door open.

Reference List:

10.: Cooking cavity
11. Top wall
12. Bottom wall
13. Rear wall
14. Side wall
15. Inlet housing

20.: Burner
21. Cylindrical casing
22. Wing unit
221 Right wing unit
222 Left wing unit
23. Middle portion
25 Longitudinal axis
26 Transverse axis
27 Orthogonal projection of the burner

30.: Exhaust Channel
31 Inlet
311 Centre
312 Cross section
313 Orthogonal projection
32 Outlet
33 Air duct
34 First piece
35 Second piece

50.: Airflow region
51. First cross section
52 Second cross section
53 Third cross section
54 Fourth cross section

90: Cooktop
91: Aperture
100.: Cooking appliance
W1:: Transverse edge of the burner
L1:: Longitudinal edge of the burner
D1:: First distance
D2:: Second distance
W3:: Width of the cross section
L3:: Length of the cross section

Claims

A cooking appliance (100) having a cooking cavity (10) defined within a top wall (11), a bottom wall (12), a rear wall (13), and opposing side walls (14) comprising, a burner (20) having a cylindrical casing (21) and at least one wing unit (22) radiating heat within said cooking cavity (10), an exhaust channel (30) having an inlet (31) which is in fluid communication with the cooking cavity (10) and an outlet (32) which is in fluid communication with an exterior of the cooking appliance (100) wherein the exhaust channel (30) is configured to allow fresh air to enter into the cooking cavity (10) and to allow exhaust gases to vent therefrom and the inlet (31) which is disposed on the top wall (11) to be aligned above a middle portion (23) of the burner (20) so as to provide an airflow region (50) provided between the wing units (22) and the top wall (11) of the cooking cavity (10), characterized in that; the inlet (31) is positioned at a predetermined location such that the inlet (31) is enclosed in an orthogonal projection of the burner (27) on a plane containing the inlet (31) wherein a cross section (312) area of the inlet (31) is sized to be less than a predetermined value, which corresponds to the sum of a first cross section (51) area which is the cross section of the airflow region (50) at the lateral left side of a left wing unit (222) and a second cross section (52) area which is the vertical cross section of the airflow region (50) at the lateral right side of a right wing unit (221), twenty percent of a third cross section (53) area which is the vertical cross section of the airflow region (50) which faces the rear wall (11) of the cooking cavity (10) and taken parallel to thereto, and twenty percent of a fourth cross section (54) area which is the vertical cross section of a front side of the airflow region (50) wherein said front side is a distal side to the rear wall (11) of the cooking cavity (10).
A cooking appliance (100) according to Claim 2, wherein at least one edge each of the first cross section (51) and the second cross section (52) of the airflow region (50) is formed by a longitudinal edge of the burner (L1), and at least one edge each of the third cross section (53) and the fourth cross section (54) of the airflow region (50) is formed by a transverse edge of the burner (W1).
A cooking appliance (100) according to Claim 3, the cross section (312) area of the inlet (31) corresponds to the sum of two times the first cross section (51) area and forty percent of the third cross section (53) area of the airflow region (50).
A cooking appliance (100) according to any of the preceding claims wherein a center (311) of the cross section (312) of the inlet (31) is arranged over the middle position (23) bisecting or nearly bisecting the transverse edge of the burner (W1).
A cooking appliance (100) according to any of the preceding claims wherein a center (311) of the cross section (312) of the inlet (31) is arranged over the middle position (23) bisecting or nearly bisecting a longitudinal edge of the burner (L1).
A cooking appliance (100) according to any of the preceding claims wherein said cross section (312) area is sized to be larger than a predetermined value depending on a power of the burner (20), a burner coefficient, and a safety factor of the burner (20).
A cooking appliance (100) according to any of the preceding claims wherein the inlet (31) is configured to be enclosed in a centred manner in an orthogonal projection of the burner (27) on a plane containing the inlet (31).
A cooking appliance (100) according to any of the preceding claims, wherein the cross section (312) of the inlet (31) is formed in a substantially rectangular shape with its minor dimension ranging from 10 % to 80 %, optionally 15 % to 35 %, of its major dimension.
A cooking appliance (100) according to any of the preceding claims, wherein the inlet (31) has a cross section (312) area within the range of from 1365 mm² to 1472 mm².
A cooking appliance (100) according to Claim 1 wherein the inlet (31) is arranged concentrically with the burner (20).
A cooking appliance (100) according to any of the preceding claims, wherein the exhaust channel (30) is formed of a substantially Z-shaped geometry.
A cooking appliance (100) according to any of the preceding claims is an oven, or a grill or a gas cooker.