Patent Description:
The invention is set out as defined by the independent claims with further embodiments defined in the dependent claims.

Disclosed herein is an airflow device to enhance the flow of air to the interior of an electronic device, such as a server. Moving ambient air to the interior of an electronic device for the purpose of cooling heat-generating components within the device may be important to maintaining peak performance of the device. In some prior configurations, baffles were placed within the chassis of a computing device in an attempt to guide air through the chassis of the computing device to specific interior regions that included heat-generating components. However, as the density of components within servers has increased, these densely packed computing device interiors in some situations have been found to impede efficient air flow through the device. For this reason, drawing sufficient air flow through the interior of such a device to various regions in need of cooling has been increasingly difficult to achieve.

Specifically, in some computing device configurations such as blade servers mounted in racks in data center environments, providing sufficient ambient air to the posterior of the device is a challenge. Cooling air may be drawn in at the front of the server by fans mounted at the back of the server; however, intervening components may impede the path of the cooling air flow so that it may not sufficiently reach posterior regions of the device. Additionally, the air that has been drawn into the device may become too hot while circulating, hindering reliable device operation. Since power supply units and hard drives are often placed near posterior regions of the device, maintaining cooler airflow to thus provide sufficient cooling for these components at the back of a device may be important. To address these issues, an example configuration of an airflow device is disclosed herein that utilizes an additional one or more channels for airflow that are provided external to the chassis of the computing device. These channels may guide airflow through slide rails of the chassis to regions internal to the chassis, thereby augmenting cooling airflow to rearward regions within the chassis.

<FIG> shows a schematic view of an example hardware environment including an electronic device <NUM> on which the airflow device <NUM> may be implemented. In this example configuration, electronic device <NUM> is a blade server that includes the airflow device <NUM>. The blade server may include a power supply unit (PSU) <NUM>, batteries <NUM>, a hard drive <NUM>, and processors <NUM>, among other components. These and other components may generate heat while in operation, thus designs that admit cooler air into the interior of the blade server may be advantageous. PSU fans <NUM> and system fans <NUM> may be placed toward the back of the electronic device <NUM> to assist in drawing air from the front side <NUM> to the back side <NUM> of the electronic device <NUM> (shown in <FIG>). A slide rail that is a first slide rail <NUM> of a server chassis <NUM> may be external to and along a side that is a first side <NUM> of the server chassis <NUM>. The slide rails of the server chassis <NUM> may allow for placement of the blade server in a server rack (not shown). The airflow device <NUM> may include a cooling air passage structure formed external to and along the side of the server chassis <NUM>. The cooling air passage structure may extend in a depth direction D of the server chassis <NUM> from the front side <NUM> of the server chassis <NUM>. In <FIG>, an example airflow is indicated by an arrow from a front side <NUM> of the electronic device <NUM> to a first vent <NUM>; the arrow is dashed where indicating airflow within the cooling air passage structure of the airflow device <NUM>. In the examples discussed below, the cooling air passage structure may be the first slide rail <NUM> of the server chassis <NUM>.

<FIG> is a magnified view of a portion of the airflow device that may be implemented in the electronic device <NUM>. An airflow channel may be formed within the cooling air passage structure, which may be referred to as a first airflow channel <NUM>. The first airflow channel <NUM> may be in the first slide rail <NUM> and extend along a depth direction D of the server chassis <NUM>. As shown in <FIG>, it will be appreciated that the first airflow channel <NUM> may be integral with the first slide rail <NUM> and external to the interior <NUM> of the server chassis <NUM>. As also shown in <FIG>, two arrows indicate a flow of air that may enter an opening of the first airflow channel <NUM> and a set of three parallel arrows indicates the direction of airflow though the first airflow channel <NUM>, the set of three parallel arrows being dashed where airflow is indicated to be internal to the first airflow channel <NUM>. One potential advantage of locating the first airflow channel <NUM> exterior to the server chassis <NUM> is that air may not be preheated before being directed to the near-vicinity of a heat-generating component, unlike air that is exclusively drawn from the front side <NUM> of the electronic device <NUM> and guided to the back side <NUM> through the server chassis <NUM>.

<FIG> is a magnified view of a portion of the airflow device <NUM> showing a depth direction D along the first side <NUM> of the server chassis <NUM> that is further to the posterior of the server chassis <NUM> than the view shown in <FIG>. As shown in <FIG>, a vent, which may be understood as a first vent <NUM>, may fluidically connect the first airflow channel <NUM> with the interior <NUM> of the server chassis <NUM> at a vent location that is rearward in the depth direction D relative to the front side <NUM>. A dashed line with an arrow tip indicates an example airflow direction along the inside of airflow device <NUM> to the first vent <NUM>. The first vent <NUM> may include a channel opening, which may be referred to as a first channel opening <NUM> that may be at a first depth <NUM> of the server chassis <NUM>, in the first airflow channel <NUM>. The first vent <NUM> may also include a chassis opening, which may be referred to as a first chassis opening <NUM>, in the server chassis <NUM>. The first chassis opening <NUM> may be coincident with the first channel opening <NUM> such that air flows from the first airflow channel <NUM> through the first channel opening <NUM> and through the first chassis opening <NUM> into the interior <NUM> of the server chassis <NUM>. Two parallel arrows in <FIG> indicate an example airflow from the vent <NUM> at the coincident openings toward a posterior of the electronic device <NUM> along the depth direction D. As shown in <FIG>, the airflow may not be introduced to the interior <NUM> of the server chassis <NUM> until the air reaches a location proximate a component to be cooled, which in this case includes the batteries <NUM>. In this example, a potential advantage of the configuration is that the airflow internal to the electronic device <NUM> need not travel very far within the interior <NUM> before reaching the batteries <NUM> to be cooled.

<FIG> is a top view of the electronic device <NUM>. As shown in <FIG>, the airflow device <NUM> may further include a second channel opening <NUM> in the first airflow channel <NUM> at a second depth <NUM> of the server chassis <NUM>. However, although the second channel opening <NUM> may be present in the first airflow channel <NUM>, an accompanying chassis opening may not be placed in the server chassis <NUM>. As further discussed below, this design may facilitate a preferred airflow from the first airflow channel <NUM> to the interior <NUM> of the server chassis <NUM> while allowing for ease of manufacture of the first and second slide rails <NUM>, <NUM>, since the same component shape may be used for each of a first and second slide rails <NUM>, <NUM>, thereby reducing the unique part count.

Given the symmetry of the server blade as shown in <FIG>, it will be appreciated that the airflow device <NUM> may further include a second slide rail <NUM> of the server chassis <NUM> external to and along a second side <NUM> of the server chassis <NUM>. A second airflow channel <NUM> that may be in the second slide rail <NUM> may extend along the depth direction D of the server chassis <NUM>. The airflow device <NUM> may further include a third channel opening <NUM> at a third depth <NUM> and a fourth channel opening <NUM> at a fourth depth <NUM> in the second airflow channel <NUM>. Although as shown in <FIG> the first depth <NUM> is depicted as equal to third depth <NUM> and the second depth <NUM> is depicted as equal to the fourth depth <NUM>, it will be appreciated that each depth of the respective channel openings may differ in some embodiments, and any particular depth placement of a given channel opening may not be equal to any other depth placement of another given channel opening.

As shown in <FIG>, a second vent <NUM> may fluidically connect the second airflow channel <NUM> with the interior <NUM> of the server chassis <NUM>. The second vent <NUM> may include the fourth channel opening <NUM> and a second chassis opening <NUM> in the server chassis <NUM>. The second chassis opening <NUM> may be coincident with the fourth channel opening <NUM> such that air flows from the second airflow channel <NUM> through the fourth channel opening <NUM> and through the second chassis opening <NUM> into the interior <NUM> of the server chassis <NUM>.

The first depth <NUM> where the first chassis opening <NUM> may be coincident with the first channel opening <NUM> in the first airflow channel <NUM> may be a different depth than the fourth depth <NUM> where the second chassis opening <NUM> may be coincident with the fourth channel opening <NUM> in the second airflow channel <NUM>. An example of this configuration is shown in <FIG>, where first channel opening <NUM> aligns with first chassis opening <NUM> to create first vent <NUM>, while second channel opening <NUM> does not align with a chassis opening and therefore admits no airflow into the interior of electronic device <NUM>. Therefore, air drawn into the first airflow channel <NUM> may be directed exclusively toward the back of the blade server to cool the PSU <NUM> and in particular the PSU batteries <NUM>. However, on the second side <NUM>, the third channel opening <NUM> does not align with a chassis opening, while the fourth channel opening <NUM> is coincident with the second chassis opening <NUM> to create the second vent <NUM>. Airflow at the second vent <NUM> may be directed primarily to the hard drive <NUM>. As shown, therefore, the first depth <NUM> is a different depth than the fourth depth <NUM> to selectively guide air to preferred locations in the interior <NUM> of the server chassis <NUM>. Therefore, airflow may be intentionally directed through the interior <NUM> of the server chassis <NUM>. However, the first and second slide rails <NUM>, <NUM> may have channel openings at the same depths along each of the slide rails, and thus the slide rails may be manufactured more easily because of this symmetry.

In an alternative configuration, a first plurality of channel openings may be formed in the first airflow channel <NUM> and a second plurality of channel openings may be formed in the second airflow channel <NUM>. Each one of the first plurality of channel openings may be at a different depth along the depth direction D and each one of the second plurality of channel openings may be at a same depth along the depth direction D as each of the first plurality of channel openings. In this configuration, each channel opening may be spaced from any other channel opening by a preferred amount, regularly or irregularly. However, by forming the second plurality of channel openings each at a same depth as the first plurality of channel openings the first and second slide rails <NUM>, <NUM> may match such that they be manufactured similarly and thus potentially more efficiently as discussed above.

Continuing in this example, one or more chassis openings in the server chassis <NUM> may be along a first side <NUM> and/or a second side <NUM> of the server chassis <NUM>. At least one vent may be formed to include one of the first and second plurality of channel openings coincident with one of the one or more chassis openings. In this configuration any one or more chassis openings may be formed to align with any of the channel openings to selectively form and place one or more vents along the first and second sides <NUM>, <NUM> of the server chassis <NUM>. Each vent may fluidically connect the at least one of the first airflow channel <NUM> and second airflow channel <NUM> with an interior <NUM> of the server chassis <NUM> at a vent location that is rearward in the depth direction D relative to the front side <NUM>. A potential advantage of this configuration is that vents may be placed strategically along the server chassis <NUM> efficiently by designing the first and second slides rails <NUM>, <NUM> with channel openings at set, predetermined locations to which chassis openings may be selectively matched.

It will be appreciated that this selective alignment of the channel openings with the chassis openings may allow for intentional placement of the vents to potentially bring relatively fresh air to the components of the interior of electronic device <NUM>, particularly to the posterior of the device <NUM>. It will be further appreciated that while the placement of each channel opening in the slide rails may be the same to facilitate manufacturing of the slide rails, placement of the chassis openings to create selectively-placed vents may ultimately determine the location of airflow from the respective airflow channels into the interior <NUM> of the server chassis <NUM>. Alternatively, it will be further appreciated that the placement of channel openings in the slide rails may be at different depths for each slide rail so that the channel openings are not symmetric along each of the slide rails. An asymmetrical design may be advantageous in some applications for vent and airflow design.

The back side <NUM> of the first airflow channel <NUM> may be blocked by a restrictor <NUM> included at a posterior end of the first airflow channel <NUM> such that heated air from a back side <NUM> of the server chassis <NUM> may be prevented from entering the first airflow channel <NUM>. This configuration may be advantageous when heat-generating components such as the PSU <NUM> are located near the back of the blade server and cause the air surrounding this region to be warmer than the ambient air. Blocking the back side <NUM> of the first airflow channel <NUM> (or second airflow channel <NUM>) may prevent this warmer air from entering the respective airflow channels.

<FIG> shows a flowchart of a method <NUM> for manufacturing an airflow device <NUM>. The following description of method <NUM> is provided with reference to the airflow device <NUM> described above and shown in the electronic device <NUM> of <FIG>. It will be appreciated that method <NUM> may also be performed in other contexts using other suitable components.

With reference to <FIG>, the method <NUM> for manufacturing an airflow device <NUM> at <NUM> may include forming a cooling air passage structure, the cooling air passage structure including an airflow channel that may be a first airflow channel <NUM> formed therein. At <NUM> the method <NUM> may include connecting the cooling air passage structure externally to and along a side that may be a first side <NUM> of a server chassis <NUM>, the cooling air passage structure and the first airflow channel <NUM> extending in a depth direction D of the server chassis <NUM> from a front side <NUM> of the server chassis <NUM>. The method <NUM> at <NUM> may include aligning a vent that may be a first vent <NUM> to fluidically connect the first airflow channel <NUM> with an interior <NUM> of the server chassis <NUM> at a vent location that is rearward in the depth direction D relative to the front side <NUM>. A potential advantage of this configuration is that, by having the cooling air passage external to the server chassis <NUM>, air drawn from outside the server that moves along the first side <NUM> of the server chassis <NUM> may not absorb a significant amount of heat before entering the interior <NUM> of the server at the first vent <NUM>. Thus, when the air finally moves through the first vent <NUM>, it may have a greater cooling impact on heat-generating components near the first vent <NUM> compared to air entering at the front side <NUM> of the server that may have to travel within the server where the air may be warmer than ambient air to the heat-generating components near the first vent <NUM>.

As described above, the cooling air passage structure may be a slide rail that may be a first slide rail <NUM> of the server chassis <NUM>. The method <NUM> may further include forming a channel opening that may be a first channel opening <NUM> in the first airflow channel <NUM> and forming a chassis opening that may be a first chassis opening <NUM> in the server chassis <NUM>. Aligning the first vent <NUM> may include aligning the first channel opening <NUM> in the e airflow channel <NUM> with the first chassis opening <NUM> e <NUM>. The first chassis opening <NUM> may be coincident with the first channel opening <NUM> such that air flows from the first airflow channel <NUM> through the first channel opening <NUM> and through the first chassis opening <NUM> into the interior <NUM> of the server chassis <NUM>. As described above, the channel opening may be a first channel opening <NUM>. The first channel opening <NUM> may be at a first depth <NUM> of the server chassis <NUM>. The method <NUM> may further include forming a second channel opening <NUM> in the first airflow channel <NUM> at a second depth <NUM> of the server chassis <NUM>. It will be appreciated that the placement of first and second channel openings <NUM>, <NUM> along the first airflow channel <NUM> may be according to a preferred design that may reflect the placement of components and/or a planned airflow within the server.

As described above, the slide rail may be a first slide rail <NUM>, the side of the server chassis <NUM> may be a first side <NUM>, the airflow channel may be a first airflow channel <NUM>, and the vent may be a first vent <NUM>. The method <NUM> may include connecting a second slide rail <NUM> of the server chassis <NUM> external to and along a second side <NUM> of the server chassis <NUM>. The method <NUM> may further include forming a second airflow channel <NUM> that may be formed in the second slide rail <NUM> and that extends along the depth direction D of the server chassis <NUM>. The method <NUM> may also include aligning a second vent <NUM> to fluidically connect the second airflow channel <NUM> with the interior <NUM> of the server chassis <NUM>. It will be appreciated that the first and second slide rails <NUM>, <NUM> may be manufactured with symmetry in mind, the first and second airflow channels <NUM>, <NUM> formed similarly within each respective slide rail. The channel openings may also be symmetric with respect to the first and second sides <NUM>, <NUM>; however, the first and second vents <NUM>, <NUM> may not symmetrically align. This design may have potential advantages as further explained below.

The method <NUM> may include forming a third channel opening <NUM> at a third depth <NUM> in the second airflow channel <NUM> and forming a fourth channel opening <NUM> at a fourth depth <NUM> in the second airflow channel <NUM>. As described above, the chassis opening may be a first chassis opening <NUM>. The method <NUM> may include forming a second chassis opening <NUM> in the server chassis <NUM>. Aligning the second vent <NUM> may include aligning the fourth channel opening <NUM> and the second chassis opening <NUM> in the server chassis <NUM>, the second chassis opening <NUM> coincident with the fourth channel opening <NUM> such that air flows from the second airflow channel <NUM> through the fourth channel opening <NUM> and through the second chassis opening <NUM> into the interior <NUM> of the server chassis <NUM>.

It will be appreciated that the first and second vents <NUM>, <NUM> may be at different depths along the first and second sides <NUM>, <NUM> of the server. That is, the first depth <NUM> where the first chassis opening <NUM> is coincident with the first channel opening <NUM> in the first airflow channel <NUM> may be a different depth than the fourth depth <NUM> where the second chassis opening <NUM> is coincident with the fourth channel opening <NUM> in the second airflow channel <NUM>. In this manner, while the channel openings may be placed at the same depths respective to the first and second sides <NUM>, <NUM> of the first and second slide rails <NUM>, <NUM> to potentially simplify the manufacturing of the slide rails, the chassis openings may be at different depths to align selectively with the channel openings. Thus, airflow may be directed as specific to each of the first and second sides <NUM>, <NUM> of the server.

As described above, a restrictor <NUM> may be included at a posterior end of the first airflow channel <NUM> such that air from a back side <NUM> of the server chassis <NUM> may be prevented from entering the first airflow channel <NUM>. As heat-generating components may be located near the back of the server, the air surrounding the server posterior may be elevated in temperature compared to ambient air farther away from the back of the server. As such, placing a restrictor <NUM> near the back of the first and second airflow channels <NUM>, <NUM> may be advantageous to maintaining airflow from the front side <NUM> of the server toward the back rather than airflow in from the back side <NUM>.

As described herein, the airflow device <NUM> may be implemented in an electronic device <NUM> to potentially draw ambient air from external the electronic device <NUM> to an interior region. Being external to the electronic device <NUM>, the airflow device <NUM> may not consume space interior to the electronic device <NUM>, thus allowing room for other components and/or allowing increased space for airflow within the electronic device <NUM>. Also, air flowing through the airflow channels may avoid being unnecessarily heated by heat generating components during its travel exterior to the chassis. Placement of the channel openings and chassis openings to create the vents at selected positions may accommodate ease of manufacture and specificity of directed airflow, particularly to regions at the posterior of the chassis.

This disclosure is presented by way of example and with reference to the associated drawing figures. Components, process steps, and other elements that may be substantially the same in one or more of the figures are identified coordinately and are described with minimal repetition. It will be noted, however, that elements identified coordinately may also differ to some degree. It will be further noted that some figures may be schematic and not drawn to scale. The various drawing scales, aspect ratios, and numbers of components shown in the figures may be purposely distorted to make certain features or relationships easier to see.

The following paragraphs provide additional support for the claims of the subject application. One aspect provides an airflow device comprising a cooling air passage structure formed external to and along a side of a server chassis, the cooling air passage structure extending in a depth direction of the server chassis from a front side of the server chassis. The airflow device includes an airflow channel formed within the cooling air passage structure, the airflow channel extending in the depth direction. The airflow device includes a vent fluidically connecting the airflow channel with an interior of the server chassis at a vent location that is rearward in the depth direction relative to the front side.

In this aspect, additionally or alternatively, the cooling air passage structure may be a slide rail of the server chassis. In this aspect, additionally or alternatively, the vent may include a channel opening in the airflow channel and a chassis opening in the server chassis. In this aspect, additionally or alternatively, the chassis opening may be coincident with the channel opening such that air may flow from the airflow channel through the channel opening and through the chassis opening into the interior of the server chassis. In this aspect, additionally or alternatively, the channel opening may be a first channel opening at a first depth of the server chassis, and the airflow device may further include a second channel opening in the airflow channel at a second depth of the server chassis.

In this aspect, additionally or alternatively, the slide rail may be a first slide rail, the side of the server chassis may be a first side, the airflow channel may be a first airflow channel, and the vent may be a first vent. The airflow device may further include a second slide rail of the server chassis external to and along a second side of the server chassis; a second airflow channel that may be in the second slide rail extending along the depth direction of the server chassis; and a second vent to fluidically connect the second airflow channel with the interior of the server chassis.

In this aspect, additionally or alternatively, the airflow device may further include a third channel opening at a third depth and a fourth channel opening at a fourth depth in the second airflow channel. In this aspect, additionally or alternatively, the chassis opening may be a first chassis opening and the second vent may include the fourth channel opening and a second chassis opening in the server chassis. The second chassis opening may be coincident with the fourth channel opening such that air may flow from the second airflow channel through the fourth channel opening and through the second chassis opening into the interior of the server chassis. In this aspect, additionally or alternatively, the first depth where the first chassis opening may be coincident with the first channel opening in the first airflow channel may be a different depth than the fourth depth where the second chassis opening is coincident with the fourth channel opening in the second airflow channel.

Another aspect provides a method for manufacturing an airflow device. The method comprises forming a cooling air passage structure, the cooling air passage structure including an airflow channel formed therein. The method further comprises connecting the cooling air passage structure externally to and along a side of a server chassis, the cooling air passage structure and the airflow channel extending in a depth direction of the server chassis from a front side of the server chassis. The method further comprises aligning a vent to fluidically connect the airflow channel with an interior of the server chassis at a vent location that is rearward in the depth direction relative to the front side.

In this aspect, additionally or alternatively, the cooling air passage structure may be a slide rail of the server chassis. In this aspect, additionally or alternatively, the method may further comprise forming a channel opening in the airflow channel and forming a chassis opening in the server chassis; aligning the vent may include aligning the channel opening in the airflow channel with the chassis opening in the server chassis. In this aspect, additionally or alternatively, the chassis opening may be coincident with the channel opening such that air may flow from the airflow channel though the channel opening and through the chassis opening into the interior of the server chassis. In this aspect, additionally or alternatively, the channel opening may be a first channel opening at a first depth of the server chassis, and the method may further comprise forming a second channel opening in the airflow channel at a second depth of the server chassis.

In this aspect, additionally or alternatively, the slide rail may be a first slide rail, the side of the server chassis may be a first side, the airflow channel may be a first airflow channel, and the vent may be a first vent. The method may further comprise connecting a second slide rail of the server chassis external to and along a second side of the server chassis; forming a second airflow channel that may be formed in the second slide rail and that extends along the depth direction of the server chassis; and aligning a second vent to fluidically connect the second airflow channel with the interior of the server chassis.

In this aspect, additionally or alternatively, the method may further comprise forming a third channel opening at a third depth in the second airflow channel and forming a fourth channel opening at a fourth depth in the second airflow channel. In this aspect, additionally or alternatively, the chassis opening may be a first chassis opening, and the method may further comprise forming a second chassis opening in the server chassis. Aligning the second vent may include aligning the fourth channel opening and the second chassis opening in the server chassis, the second chassis opening coincident with the fourth channel opening such that air may flow from the second airflow channel through the fourth channel opening and through the second chassis opening into the interior of the server chassis. In this aspect, additionally or alternatively, the first depth where the first chassis opening may be coincident with the first channel opening in the first airflow channel may be a different depth than the fourth depth where the second chassis opening may be coincident with the fourth channel opening in the second airflow channel.

Another aspect provides an airflow device comprising a first cooling air passage structure that is a first slide rail of a server chassis formed external to and along a first side of the server chassis, the cooling air passage structure extending in a depth direction of the server chassis from a front side of the server chassis. The airflow device includes a second cooling air passage structure that is a second slide rail of the server chassis formed external to and along a second side of the server chassis, the second cooling air passage extending in the depth direction of the server chassis from the front side of the server chassis. The airflow device includes a first airflow channel formed within the first cooling air passage structure and a second airflow channel formed within the second cooling air passage structure, the first and second airflow channels extending in the depth direction. The airflow device includes a first plurality of channel openings in the first airflow channel and a second plurality of channel openings in the second airflow channel, each one of the first plurality of channel openings at a different depth along the depth direction and each one of the second plurality of channel openings at a same depth along the depth direction as each of the first plurality of channel openings. The airflow device includes one or more chassis openings in the server chassis along a first side and/or second side of the server chassis and at least one vent including one of the first and second plurality of channel openings coincident with one of the one or more chassis openings to fluidically connect at least one of the first and second airflow channels with an interior of the server chassis at a vent location that is rearward in the depth direction relative to the front side.

Claim 1:
A combination of a server chassis (<NUM>) for an electronic device (<NUM>) and an airflow device (<NUM>), comprising:
a cooling air passage structure formed external to and along a side of the server chassis, the cooling air passage structure extending in a depth direction of the server chassis from a front side of the server chassis;
an airflow channel (<NUM>) formed within the cooling air passage structure, the airflow channel extending in the depth direction; and
a vent (<NUM>, <NUM>) fluidically connecting the airflow channel with an interior of the server chassis at a vent location that is rearward in the depth direction relative to the front side;
wherein the cooling air passage structure is a slide rail of the server chassis;
wherein the slide rail is a first slide rail (<NUM>), the side of the server chassis is a first side, the airflow channel is a first airflow channel, and the vent is a first vent(<NUM>), further comprising:
a second slide rail (<NUM>) of the server chassis external to and along a second side of the server chassis;
a second airflow channel (<NUM>) that is in the second slide rail extending along the depth direction of the server chassis; and
a second vent (<NUM>) to fluidically connect the second airflow channel with the interior of the server chassis.