DE102020107955A1 - Jet fan for ventilation of tunnels, jet fan system and processes - Google Patents

Abstract

The invention relates to a jet fan for ventilating tunnels, in particular road tunnels, a jet fan system and a method for producing a jet fan for ventilating tunnels. In particular, the invention relates to a jet fan for ventilating tunnels, in particular road tunnels, comprising a fan unit (106) for generating an air flow, a silencer (110, 130) arranged on the fan unit (106) with a proximal section (112) and an the distal section (116) adjoining the proximal section (112), characterized in that an angle (120, 122) is established between the distal section and the proximal section.

Description

The invention relates to a jet fan for ventilating tunnels, in particular road tunnels, a jet fan system and a method for producing a jet fan for ventilating tunnels.

Jet fans for ventilating tunnels are known in principle. Such jet fans ventilate and ventilate tunnels, in particular road tunnels, so that high concentrations of exhaust gases in the tunnels can be avoided. Jet fans generate an air flow by means of a fan arranged in a fan shaft, which enters the tunnel at one end of the tunnel and exits again at the other end of the tunnel. The ingress and egress of this air flow can also take place at different locations from the ends of the tunnel, for example by air inflows in the middle of the tunnel. In order to reduce the noise emissions of the jet fan, they usually have silencers.

The air flow within a tunnel has a velocity profile, the flow velocity being low in the floor, ceiling and side sections and increasing towards a central section of the tunnel. The highest flow velocity can usually be achieved in the middle of the tunnel. In terms of flow, it would be advantageous to arrange the jet fan in the middle of the tunnel. However, such an arrangement would reduce the headroom in the tunnel and is therefore generally not practical in practice, since either the height would not be sufficient or the height of the tunnel would have to be increased disproportionately.

As a result, jet fans are usually arranged near the wall and / or ceiling of the tunnel. However, the fan power is converted less and less into an effective air flow through the entire tunnel, the closer the jet fan is arranged to the tunnel wall or the tunnel ceiling. This means in particular that the closer a jet fan is arranged to the tunnel wall or the tunnel ceiling, the worse its efficiency.

In the DE19920513A1 a jet fan is taught which has a nozzle arrangement at the fan inlet and at the fan outlet. The jet fan sucks in the air from the center of the tunnel more easily and expels the air flow accelerated by the fan in the direction of the center of the tunnel. This jet fan improves the ventilation of tunnels, but the headroom is negatively influenced by the jet fan.

Since jet fans for ventilating tunnels reduce the clearance height and therefore a higher tunnel height may have to be provided, it is a requirement of jet fans that they have as little negative impact on the clear height as possible. In addition, it is a requirement of jet fans that as few jet fans as possible are used when providing a defined air flow through the tunnel, since the jet fans as such and their installation and maintenance as well as the cables to be laid cause high costs.

It is therefore an object of the invention to provide a jet fan for ventilating tunnels, in particular road tunnels, a jet fan system for ventilating tunnels, in particular road tunnels, and a method for producing a jet fan for ventilating tunnels, particularly road tunnels, which have a or reduce or eliminate several of the disadvantages mentioned. In particular, it is an object of the invention to provide a solution which reduces the number of jet fans required within a tunnel and / or the costs for jet fans for ventilating a tunnel.

According to a first aspect, this object is achieved by a jet fan for ventilating tunnels, in particular road tunnels, comprising a fan unit for generating an air flow, a silencer arranged on the fan unit with a proximal section and a distal section adjoining the proximal section, characterized that an angle is established between the distal section and the proximal section.

The invention is based on the knowledge that the sound absorbers of a jet fan have a significant influence on the clearance between the jet fan and the roadway. Since the efficiency of a jet fan decreases the closer it is arranged to the tunnel ceiling or the tunnel wall, known jet fans are either arranged at a greater distance from the tunnel ceiling or the tunnel wall or the silencer is arranged at an angle to the fan unit so that the air flow is directed into the center of the tunnel .

However, the inclined arrangement of the silencers reduces the clearance between the jet fan and the roadway. Alternatively, a jet fan with essentially non-inclined sound absorbers can also be used, but then the fan unit must have a large diameter so that the clear height is also reduced. There is also the option of increasing the number of jet fans increase, but this is usually not a suitable solution from an economic perspective.

In a clever way, the jet fan described above enables the jet fan to be arranged directly under a tunnel ceiling and also enables a large clearance between the jet fan and a roadway, in that an angle is set between the distal section and the proximal section, so that in particular the distal section is inclined with respect to the ventilator unit and / or the proximal section. The proximal section can be arranged coaxially to the fan unit. Thus, the jet fan described above combines the advantages of a jet fan without inclined silencers with regard to the headroom and the advantages of a jet fan with inclined silencers with regard to the effective air flow.

The invention thus makes it possible to provide a jet fan with a larger diameter without reducing the clear height. A thrust generated by a jet fan is determined, among other things, from the fourth power of the diameter. For example, a diameter increase of 12% leads to an increase in thrust of 50%. As a result, for example, by increasing the size of the jet fans by a standard size, the number of jet fans for a tunnel can be reduced by 30% to 35%, so that the cost of ventilation can be reduced significantly. The inventor has also found that an increase by two standard sizes is also possible, so that the number of jet fans for a tunnel is reduced by 60%. In Germany, for example, the standard sizes result from a standard.

In addition, it must be taken into account that there are official requirements for tunnels regarding the sound level. For a given thrust, the length of the silencer is usually set within a narrow design window. The silencers which are known in the prior art and inclined towards the road were limited in terms of their length in order to ensure a sufficient headroom. The invention now makes it possible to provide the silencer in any length, since an extension of the proximal section does not lead to a reduction in the clear height.

The jet fan comprises the fan unit for generating an air flow. The fan unit usually has a fan shaft in which a propeller is rotatably mounted. The propeller is usually coupled to an electric drive that rotates the propeller. The fan unit usually has an inlet and an outlet in the direction of flow. Since it can be advantageous that the direction of flow is reversed, the inlet can also act as an outlet and the outlet as an inlet. A silencer is preferably arranged at the inlet and / or at the outlet. At least one silencer is arranged at the inlet or at the outlet.

The muffler has at least a proximal section and a distal section. The proximal section preferably faces the ventilator unit, with the distal section facing away from the ventilator unit. The angle is established between the distal section and the proximal section, so that in particular the distal section is oriented at an incline to the proximal section.

The angle can be an external angle and / or an internal angle, for example. It is particularly preferred that a passage axis of the proximal section and a passage axis of the distal section enclose a passage angle and / or are not aligned in parallel. The proximal section of the muffler can, for example, be designed as a cylindrical casing element. In addition, the distal section can also be designed as a cylindrical jacket element. The muffler can be made in one piece or in two pieces.

According to a preferred embodiment of the jet fan, it is provided that the distal section is designed to guide an air flow generated by the fan unit from a radially outer section of the tunnel into a substantially central section of the tunnel. In addition, the distal section can be designed so that an air flow generated by the fan unit is guided into the fan unit from an essentially central section of the tunnel. Since the direction of flow through the fan unit can be reversed, the distal section can thus be used on the one hand for blowing out or for sucking in the air. Such a design of the distal section achieves an advantageous air flow inside a tunnel.

Another preferred development of the jet fan is characterized in that the proximal section defines a proximal flow direction and the distal section defines a distal flow direction, the proximal flow direction enclosing a flow angle with the distal flow direction. During operation, the proximal flow direction can, for example, be oriented essentially parallel to a longitudinal axis of the tunnel. The distal flow direction is preferably in the operation of the jet fan from directed a tunnel ceiling or a tunnel wall in the direction of a central section of the tunnel. As a result, the flow angle is set between the proximal flow direction and the distal flow direction.

Furthermore, it is preferred that the fan unit defines a fan flow direction, the fan flow direction and / or the proximal flow direction including or including the flow angle with the distal flow direction. The flow angle corresponds in particular to the angle.

The aforementioned flow directions, that is to say the proximal flow direction, the distal flow direction and the fan flow direction, are to be understood as meaning, in particular, a main flow direction. The main flow direction is defined by the fact that it represents the basic flow direction inside the jet fan. Of course, for example, in the vicinity of an inner wall of the jet fan or on elements arranged inside the jet fan, flows can occur which are partially directed transversely or also in the opposite direction to the main flow direction. Such local flow directions occurring in the interior of the jet fan, however, are generally not meant by the flow directions mentioned above.

In a further preferred embodiment it is provided that a fan flow direction of the fan unit and the proximal flow direction are aligned essentially parallel to one another. In an advantageous manner, a short projection length transversely to the tunnel axis is thus ensured.

It is particularly preferred that the flow angle is between 2 ° and 15 °, in particular between 4 ° and 10 °, preferably between 6 ° and 8 °. The inventors have found that it is precisely with such flow angles that a good flow can be achieved inside a tunnel, taking into account a small number of jet fans.

Furthermore, it is preferred that the proximal section define a proximal passage axis and the distal section define a distal passage axis, the proximal passage axis enclosing a passage angle with the distal passage axis. In addition, it is preferred that the fan unit defines a fan passage axis and the fan passage axis and the proximal passage axis are aligned essentially parallel to one another, wherein these can also be aligned coaxially in a preferred development. In addition, it is preferred that the proximal passage axis and the distal passage axis enclose an angle between 2 ° and 15 °, in particular between 4 ° and 10 °, preferably between 6 ° and 8 °.

In a further preferred embodiment variant of the jet fan it is provided that the proximal section is arranged between the distal section and the fan unit.

In particular, it is preferred that the proximal section is arranged in the fan flow direction and / or in the proximal flow direction and / or in the distal flow direction between the distal section and the fan unit. Such an arrangement advantageously influences the air flow through the jet fan.

Another preferred development of the jet fan is characterized in that the silencer is designed in two parts with a first silencer unit and a second silencer unit, the first silencer unit having the proximal section and the second silencer unit having the distal section. By means of a jet fan designed in this way, a simple and inexpensive construction of this jet fan, which positively influences the air flow, can be ensured.

Another preferred embodiment of the jet fan is characterized in that the proximal section extends in the proximal flow direction with a proximal extent and the distal section extends in the distal flow direction with a distal extent, the distal extent being smaller than the proximal extent. In this preferred embodiment variant, the ratio of distal extension and proximal extension is less than 1.

In a further preferred embodiment variant of the jet fan it is provided that the ratio of distal extension and proximal extension is between 0.05 and 0.4, in particular between 0.1 and 0.3. The inventors have found that, in particular with such a ratio, a further improvement in the flow conditions inside a tunnel can be achieved.

In addition, the jet fan can be developed in such a way that the fan unit and / or the silencer has or have a flow diameter and the ratio of distal extension and flow diameter between 0.2 and 0.75, in particular between 0.45 and 0.55 , is, and / or the ratio of proximal extent and flow diameter is between 1 and 4, in particular between 2 and 3.

The flow diameter is in particular a dimension of the cross section, the surface orthogonal of which is aligned parallel to the flow direction and / or to the passage axis. The flow diameter of the fan unit is generally to be understood as neglecting elements and / or systems built into the fan unit.

In a further preferred embodiment of the jet fan it is provided that it comprises a second silencer, which preferably has the same features as the silencer, the silencer at a first end and the second silencer at a second end arranged opposite the first end in the fan flow direction the fan unit is arranged. The noise immission of the jet fan is further reduced by the silencer and the second silencer. In particular, a mirror-symmetrical steel fan is thus made possible, so that a reversal of the flow direction is made possible in an advantageous manner.

In a further preferred embodiment it is provided that the jet fan comprises a fastening unit which is arranged and designed to fasten the jet fan to a tunnel ceiling and / or a tunnel wall in such a way that a cantilever width is less than 1.3 times, in particular less than 1.1 times the flow diameter. In addition, it is preferred that the distal flow direction on an outlet side of the jet fan is directed into an essentially central section of the tunnel.

In addition, it can be preferred that the jet fan has a nozzle element which comprises a casing segment that extends from an inlet to an outlet with a ring segment-shaped cross section and defines a nozzle throughflow direction, the casing segment having a circumferential opening section adjoining the outlet comprises, and also comprises connection means which are designed for coupling the nozzle element to the silencer and / or the second silencer.

According to a further aspect, the above-mentioned object is achieved by a jet fan system for ventilating tunnels, in particular road tunnels, comprising at least one jet fan according to one of the embodiment variants described above, the at least one jet fan having a supply cable that couples the jet fan to a power supply .

The invention is based on the knowledge that approx. 1/3 of the total costs of a jet fan system relate to the electrical equipment, such as switch cabinets, cables, etc. Because of this, the reduction in the total number of jet fans for a jet fan system is advantageous, since the total cable length to be laid is reduced. Since a further third of the total costs are accounted for by installation and assembly, this reduces another cost point.

According to a further aspect, the above-mentioned object is achieved by a method for producing a jet fan for ventilating tunnels, in particular road tunnels, comprising the steps of: providing a fan unit for generating an air flow, providing a silencer with a proximal section and one on the proximal section Section adjoining distal section, wherein the distal section and the proximal section form an angle with one another and fastening the silencer to the fan unit, the proximal section facing the fan unit and the distal section facing away from the fan unit.

The method and its possible further developments have features or method steps that make them particularly suitable for being used for a jet fan described above and its further developments. For further advantages, design variants and design details of the further aspects and their possible further developments, reference is also made to the description given above for the corresponding features and further developments of the jet fan.

• 1: eine schematische, zweidimensionale Schnittansicht einer beispielhaften Ausführungsform eines Strahlventilators;
• 2: eine schematische, dreidimensionale Seitenansicht eines im Stand der Technik und eines erfindungsgemäßen Strahlventilators;
• 3: eine schematische, dreidimensionale Seitenansicht eines im Stand der Technik und eines erfindungsgemäßen Strahlventilators; und
• 4: eine schematische Ansicht eines Verfahrens.

Preferred exemplary embodiments are explained by way of example with the aid of the accompanying figures. Show it:

• 1 : a schematic, two-dimensional sectional view of an exemplary embodiment of a jet fan;
• 2 : a schematic, three-dimensional side view of a jet fan according to the prior art and a jet fan according to the invention;
• 3 : a schematic, three-dimensional side view of a jet fan according to the prior art and a jet fan according to the invention; and
• 4th : a schematic view of a process.

Identical or essentially functionally identical or similar elements are denoted by the same reference symbols in the figures.

The jet fan 100 extends from an inlet 102 towards an outlet 104 . In this exemplary representation, the air flows at the inlet 102 in the jet fan 100 and flows in at the outlet 104 out again. The direction of flow of the jet fan 100 however, it can also be reversed so that the air at the outlet 104 in the jet fan 100 entrance and at the entrance 102 from the jet fan 100 exit. The jet fan 100 has a fan unit 106 , a first muffler 110 and a second muffler 130 on. The fan unit 106 defines a fan flow direction 108 . In normal operation of the jet fan 100 is the fan flow direction 108 aligned essentially parallel to a longitudinal axis of the tunnel.

The first silencer 110 has a proximal section 112 with a proximal flow direction 114 and a distal section 116 with a distal flow direction 118 on. Between the distal section 116 and the proximal section 112 an angle arises 122 a. Because of this angle 122 In addition, there is an angle between the proximal flow direction 114 and the distal flow direction 118 one, namely the flow angle 120 . In the present exemplary embodiment, is the sum of the flow angle 120 and that on the outer skin between the distal section 116 and the proximal section 112 setting angle 122 together 180 degrees of arc.

On one in the fan flow direction 108 , the first silencer 110 facing away from the jet fan 100 , is the second muffler 130 arranged. The second silencer 130 points analogous to the first silencer 110 a proximal section 132 and a distal section 134 on, between which there is an angle 136 adjusts.

The jet fan 100 can with a fastening unit 138 be attached to a tunnel wall or a tunnel ceiling. By building the muffler with distal sections 116 , 134 and proximal sections 112 , 132 allows the fan unit 106 and the proximal sections 112 , 132 can be arranged close to the wall or ceiling. Despite this arrangement close to the ceiling or wall, the kinked distal sections 116 , 134 a big boost from the jet fan 100 generated on the airflow. As a result, the jet fan can 100 can be designed with a smaller flow diameter or the total number of jet fans in a tunnel can be reduced.

This advantage is made possible by the representation in the 2 and 3 clear. In the 2 is a jet fan known in the prior art on the left 200 shown. This jet fan 200 is on a tunnel ceiling 202 over a roadway 204 arranged. By spacing the tunnel ceiling 202 and roadway 204 as well as the overhang 208 there is a clear height 206 . The clear height 206 defines the passage height of the tunnel with a safety distance. The conventional jet fan 200 needs a greater distance from the tunnel ceiling 202 have so that its efficiency is not too low.

Due to the distance from the tunnel ceiling 202 becomes the headroom 206 significantly reduced. In the present example, with a total height between the carriageway 204 and the ceiling 202 from 4 to 5 flow diameters the clearance height is only 2.5 to 3.5 times the flow diameter.

In contrast, you can use the jet fan shown on the right 210 a greater headroom 216 from three to four times the flow diameter can be achieved. In addition, the jet fan can 210 a smaller distance from the tunnel ceiling 212 exhibit. The overhang 218 is due to the smaller distance from the tunnel ceiling 212 compared to the arrangement of the jet fan 210 smaller, namely about 0.4 times the flow diameter.

In 3 the comparison between two jet fans is also shown, namely the conventional jet fan 200 and the jet fan 210 according to the invention. Due to the smaller distance from the tunnel ceiling 212 can be a larger diameter for the jet fan 210 chosen so that the same overhang 208 , 218 is achieved. Due to the larger flow diameter of the jet fan 210 however, a larger thrust can be achieved, so that a smaller number of jet fans 210 must be arranged in the tunnel. This significantly reduces the assembly and installation work as well as the total cable length to be laid. As a result, the cost of ventilating the tunnel is reduced.

In 4th a schematic view of a process is shown. In step 300 a fan unit 106 provided for generating an air flow. In step 302, a muffler is created 110 , 130 with a proximal section 112 , 132 and one to the proximal section 112 , 132 adjacent distal section 116 , 134 provided, the distal portion 116 , 134 and the proximal section 112 , 132 an angle 122 , 136 include with each other. In step 304, the muffler 110 , 130 on the fan unit 106 attached, with the proximal section 112 , 132 the fan unit 106 facing and the distal section 116 , 134 the fan unit 106 is turned away. The proximal section 112 , 132 can for example fasteners for fastening to the fan unit 106 exhibit.

List of reference symbols

100

Jet fan

102

inlet

104

Outlet

106

Fan unit

108

Fan flow direction

110

first muffler

112

proximal section

114

proximal flow direction

116

distal section

118

distal flow direction

120

Flow angle

122

angle

130

second silencer

132

proximal section

134

distal section

136

angle

138

Fastening unit

200

first jet fan

202

Tunnel ceiling

204

roadway

206

clear height

208

Overhang

210

second jet fan

212

Tunnel ceiling

214

roadway

216

clear height

218

Overhang

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 19920513 A1 [0005]

Claims (14)

Jet fan (100, 210) for ventilating tunnels, in particular road tunnels, comprising - a fan unit (106) for generating an air flow, - a silencer (110, 130) arranged on the fan unit (106) with a proximal section (112) and a distal section (116) adjoining the proximal section (112), - characterized in that an angle (120, 122) is established between the distal section (116) and the proximal section (112). Jet fan (100, 210) Claim 1 , wherein the distal section (116) is designed to guide an air flow generated by the fan unit (106) from a radially outer section of the tunnel into a substantially central section of the tunnel and / or from a substantially central section of the tunnel into the To guide the fan unit (106). Jet fan (100, 210) according to one of the preceding claims, wherein the proximal section (112) defines a proximal flow direction (114) and the distal section (116) defines a distal flow direction (118), the proximal flow direction and the distal flow direction forming a flow angle (120) includes. Jet fan (100, 210) according to one of the preceding claims, wherein a fan flow direction (108) of the fan unit (106) and the proximal flow direction (114) are oriented essentially parallel to one another. Jet fan (100, 210) according to one of the preceding claims, wherein the flow angle (120) is between 2 degrees and 15 degrees, in particular between 4 degrees and 10 degrees, preferably between 6 degrees and 8 degrees. Jet fan (100, 210) according to one of the preceding claims, wherein the proximal section (112) is arranged between the distal section (116) and the fan unit (106). Jet fan (100, 210) according to one of the preceding claims, wherein the silencer (110, 130) is designed in two parts with a first silencer unit and a second silencer unit, the first silencer unit the proximal section (112) and the second silencer unit the distal section ( 116). Jet ventilator (100, 210) according to one of the preceding claims, wherein the proximal section (112) extends in the proximal flow direction (114) with a proximal extension and the distal section (116) extends in the distal flow direction (118) with a distal extent, the distal extent being smaller than the proximal extent. Jet fan (100, 210) according to one of the preceding claims, wherein the ratio of distal extension and proximal extension is between 0.05 and 0.4, in particular between 0.1 and 0.3. Jet fan (100, 210) according to one of the preceding claims, wherein - the fan unit (106) and / or the silencer (110, 130) has or have a flow diameter, and the ratio of distal extension and flow diameter is between 0.2 and 0.75, in particular between 0.45 and 0.55, and / or the ratio of the proximal extent and the flow diameter is between 1 and 4, in particular between 2 and 3. Jet fan (100, 210) according to one of the preceding claims, comprising a second silencer (110, 130), which preferably has the same features as the silencer (110, 130), the silencer (110, 130) at a first end and the second silencer (110, 130) is arranged on a second end of the fan unit (106) which is arranged opposite the first end in the fan flow direction. Jet fan (100, 210) according to one of the preceding claims, comprising a fastening unit (138) which is arranged and designed, - to attach the jet fan (100, 210) to a tunnel ceiling and / or a tunnel wall in such a way that a projection width is less than 1.3 times, in particular less than 1.1 times, the flow diameter, and / or - That the distal flow direction (118) on an outlet side of the jet fan is directed into a substantially central section of the tunnel. Jet fan system for ventilating tunnels, in particular road tunnels, comprising - At least one jet fan (100, 210) according to one of the preceding claims, - wherein the at least one jet fan (100, 210) has a supply cable which couples the jet fan (100, 210) to a power supply. A method for producing a jet fan (100, 210) for ventilating tunnels, in particular road tunnels, comprising the steps: Providing a fan unit (106) for generating an air flow, - providing a silencer (110, 130) with a proximal section (112) and a distal section (116) adjoining the proximal section (112), wherein between the distal section ( 116) and the proximal section (112) sets an angle (120, 122), and - attaching the silencer (110, 130) to the fan unit (106), with the proximal section (112) facing the fan unit (106) and the distal section (116) faces away from the fan unit (106).

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