FORM -2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003 PROVISIONAL
Specification
(See Section 10; rule 13)
COOLING SYSTEMS
COMPUTATIONAL RESEARCH LABORATORIES LTD.
an Indian Company of Survey No. 103/A. Ground Floor, Pride Portal, Bahirat Wadi, Senapati Bapat Road, Pune 411 016, Maharashtra, India
THE FOLLOWING SPECIFICATION DESCRIBES THE INVENTION

Field of the Invention:
The invention relates to cooling systems.
Background of the Invention:
Centers with a plurality of heat generating systems are known aplenty. Some of these systems may include servers, storage devices, network systems, industrial equipment, power supply units, interconnect switches, data centers, and the like. Typically, this invention is defined in relation to a data center or a computing system, but it may be understood that the same application of cooling may be extended without departing from the scope of this invention and its claimed features to any system or network which comprise heat generating equipment/units located remotely/discretely from each other over a defined area.
A data center, typically, refers to an assembly of computing units and its peripheral interfacing components, such as, telecommunication units, and power supply units, various communication units, security units, and the like; all assembled to work in synchronization for a variety of input and output preferences. A high performance computing data center is the data center implemented on a mega-scale, with many parallel and serially located components, adapted to perform highly complex calculations.
A data center can occupy one room of a building, one or more floors, or an entire building. Most of the equipment is often in the form of servers mounted in rack cabinets, which are usually placed in single rows forming corridors between them or in rows in parallel. This allows people access to the front and rear of each cabinet.

Such servers and computer systems, individually, and especially collectively, are capable of generating a large amount of heat during its operation. Every component of the computing system has a definite range of acceptable working temperatures for optimum and long-term utilization. It is hence, imperative to keep temperatures under check. Moreover, temperature fluctuations impact humidity within the room housing the computing systems. Temperature fluctuations affect server performance and reliability. It is also important to have a proper passageway for the aligned flow of air as opposed to a random flow of cold and hot air which should result in efficient cooling and management of pressures and humidity.
Prior Art:
Previous models of data center were cooled using a 'row and column' approach or the 'hot and cold aisle' arrangement, wherein, a plurality of servers were located in one row and the cooling system was placed at centralized location. The cold air discharged from the cooling systems into a plenum formed by a sub-floor and a raised floor. From this plenum, the air was then discharged through perforated raised floor tiles, strategically located near the racks hosting said servers. The plenum formed by the space between the raised floor and the sub-floor provides a means to supply chilled air through the perforated tiles making up the raised floor, thereby providing cool air to the servers on the racks [as shown in Figure 1]. Typically, the plenum height was about 600 mm to 800 mm above the real floor. Four vertical studs/supports fixed on the real floor, for each tile, supported the raised floor. The plenum space was also used for routing network cables, electric cables, trays for supporting these cables, cold water pipes and the

like items, which led to increasing the fluid resistance and hence, resulted into decreasing the air velocity that was supposed to flow through the plenum. Also, there was a chance of air leakages and hence not obtaining the desired airflow at the strategically located perforated raised floor tiles.
Objectives of the Invention:
An object of the invention is to provide a cooling system for a data center such that there is a direct air supply to the servers of said data center.
Another object of the invention is to provide a cooling system for a data center with optimum and uniform air flow distribution.
Yet another object of the invention is to provide a cooling system for a data center with reduced complexity.
Still another object of the invention is to provide a cooling system for a data center with increased efficiency.
An additional object of this invention is to provide a cooling centre for a data center with very high heat density.
Summary of the Invention:
In accordance with this invention, there is provided a cooling system for a plurality of servers located in a data center. The cooling system includes a set of computer servers located along a first pre-defined locus of points and corresponding cooling devices located along a second pre-defined locus of points. The first pre-defined locus of points and the second pre-defined locus

of points detail the architectural set-up for the components of the data centre vis-a-vis the cooling system of the data centre.
In accordance with another embodiment of this invention, the components of the data centre, typically, the servers form the heat sourcing apparatus, located along a first pre-defined locus of points. The heat sourcing system along the first pre-defined locus of points forms the 'hot-aisle'.
In accordance with yet another embodiment of this invention, a cooling system is envisaged, said cooling system comprising a plurality of active cooling devices, in which, each of said cooling device is kept in front of said heat sourcing apparatus, said cooling system being located along a second pre-defined locus of points. By means of this configuration, cold air from the cooling device is directly supplied to the heat sourcing apparatus, thus avoiding resistance in fluid path. This arrangement is typically envisaged to increase cooling efficiency by approximately 15-20%, as compared with conventional cooling arrangement of the prior art. The cooling system along the second pre-defined locus of points form the 'cold-aisle'
In accordance with still another embodiment of this invention, said cooling device is adapted to be placed over a plenum adapted to supply air. In its operative configuration, the cooling device placed atop said plenum provides cooled air to the plenum for dissemination through it, to the heat sourcing apparatus.
In accordance with yet another embodiment of this invention, there is provided a physical isolation embodiment between the 'hot-aisle' and 'cold-

aisle' to avoid short-circuiting of hot and cold air sourced from respective aisles.
In accordance with an additional embodiment of this invention, said first and said second pre-defined locus of points form a circle.
In accordance with yet an additional embodiment of this invention, said first and said second pre-defined locus of points form a polygon.
Brief Description of the Accompanying Drawings:
Figure 1 illustrates a schematic illustration of a data centre along with a cooling system of the prior art.
The invention will now be described in relation to the accompanying drawings, in which:
Figure 2 illustrates a schematic illustration of a data centre along with a cooling system;
Figure 3 illustrates a schematic illustration of one portion of the data centre along with the cooling system; and
Figure 4 illustrates a schematic map of the data centre along with the cooling system of the schematic illustration.

Detailed Description of the Accompanying Drawings:
Figure 1 illustrates a schematic illustration of a data centre along with a cooling system of the prior art. In conventional data centres, heat sources (computer racks) (CR) are arranged in rows and columns fashion. Centrally located cooling devices (AC) deliver chilled air to a plenum (P) formed by sub floor (SF) and raised floor (RF). From this plenum (P) the chilled air is then discharged through perforated raised floor tiles (PRF) strategically located near compute racks (CR). Typically, supply air plenum (P) height is 600 to 800 mm above the sub floor. The supply air plenum (P) contains lots of network cables, electrical cables, cable trays, supply and return water pipes, raised floor vertical supports, interconnect cables, etc. which reduces the total volume of supply air plenum (P) and offering more resistance to fluid (air) resulted into decreasing the air velocity. Also, many times, in accordance with this arrangement, the hot return air mixes with the cold air path, since two zones are not physically isolated, thus, increasing the temperature of cold air supplied to computer servers hence reducing the effect of cold air.
Figure 2 illustrates a schematic illustration of a data centre along with a cooling system. In accordance with this invention, there is provided a
cooling system for a plurality of servers (SI, S2, Sn) located in a data
center. The cooling system includes a set of computer servers (SI,
S2, Sn) located along a first pre-defined locus of points and
corresponding cooling devices (CI, C2,....Cn) located along a second pre¬defined locus of points. The first pre-defined locus of points and the second pre-defined locus of points detail the architectural set-up for the components of the data centre vis-a-vis the cooling system of the data centre. In

accordance with another embodiment of this invention, the components of
the data centre, typically, the servers (Sil, Si2, Sin) form the heat
sourcing apparatus, located along a first pre-defined locus of points. Typically, this figure illustrates two sets of heat Sourcing devices, an inner
source (Sil, Si2, Sin) and outer source (Soj; So2, Son) and the
intermittent gap between said two sets of heat sourcing devices form the
'hot-aisle' (HA). In accordance with yet another embodiment of this
invention, a cooling system is envisaged, said cooling system comprising a
plurality of active cooling devices, in which, each of said cooling device is
kept in front of said heat sourcing apparatus, s^id cooling system being
located along a second pre-defined locus of points. By means of this
configuration, cold air from the cooling device is directly supplied to the
heat sourcing apparatus, thus avoiding resistance in fluid path. This
arrangement is typically envisaged to increase cooling efficiency by
approximately 15-20%, as compared with conventional cooling arrangement
of the prior art. Typically, a first set of cooling (devices (Cil, Ci2,....Cin)
service a first set of heat sources (Sil, Si2,....Sm), and a second set of
cooling devices (Col, Co2,....Con) service a second set of heat sources
(Sol, So2,....Son). The intermittent gaps between the first set of cooling
devices (Cil, Ci2,....Cin) and corresponding inner heat sources (Sil,
Si2,....Sin), and between the second set of cooling devices (Col,
Co2,....Con) and corresponding outer heat sources (Sol, So2,....Son) form
the 'cold aisles' (CA). In accordance with yet another embodiment of this
invention, there is provided a physical isolation embodiment between the
'hot-aisle' (HA) and 'cold-aisle' (CA) to avoid short-circuiting of hot and
cold air sourced from respective aisles.

Figure 3 illustrates a schematic illustration of one portion of the data centre along with the cooling system. It illustrates one node of the server (Sil) along with one node of the cooling device (Cil). In accordance with this invention, said cooling device (Cil) is adapted to be placed over a plenum (P) adapted to supply air. In its operative configuration, the cooling device (Cil) placed atop said plenum (P) provides cooled air to the plenum (P) for dissemination through it, to the heat sourcing apparatus (Sil). Heat source (Sil) will dissipate heat into cold air and discharged hot air into hot aisle (HA). The hot air is then returned back to the cooling device (Cil) which reduces the temperature of air to desired value. The hot aisle (HA) and cold aisle (CA) are physically isolated to avoid short circuiting of hot and cold air. However, if the pressure in cold aisle (CA) is too high, and the excess airflow is available in cold aisle (CA), the cold air will allow to flow into hot aisle (HA). This arrangement will be useful to reduce the hot aisle (HA) temperature and decrease the return air temperature. The sub-floor (SF), raised floor (RF), and the true ceiling (TC) of the data centre are also shown.
Figure 4 illustrates a schematic map of the data centre along with the cooling system of the schematic illustration. The cooling units (AC units) are placed in front of heat sourcing apparatus (computer racks), and provide chilled air to one or more heat sourcing apparatus (computer racks), based on its pre¬defined capacity. Cold air is discharged in front of heat sourcing apparatus (computer racks). Hot air is collected into backside of both heat sourcing apparatus (computer racks) and returned back to cooling units (AC units). Hot aisle (HA) and cold aisle (CA) along with airflow direction are also shown.