OA17247A - Automotive cabin environment management system. - Google Patents

Abstract

The present disclosure provides an automotive cabin environment management system comprising : an enclosure, first air filer mounted on top of the enclosure, one or more air conditioning unit mounted within enclosure. The one or more air conditioning unit receives atmospheric air via the first air filter to generate conditioned air to be supplied to a cabin of the vehicle. A plurality of second air filters are mounted below the enclosure, wherein each of the plurality of second air filters are located on either sides of the first air filter and are fluidly communicably attached to one of the one or more air conditioning unit. Further, a plurality of connecting ducts are provided in the system for recirculating the air. At least one motorized flap is mounted within the plurality of connecting ducts to direct the air flow from roof ducts into the evaporative heat exchangers in severe mode of operation.

Description

AUTOMOTIVE CABIN ENVIRONMENT MANAGEMENT SYSTEM

TECHNICAL FIELD

Embodiments of the disclosure relates to an air conditioning system. More particularly embodiments of the disclosure relates to an improved evaporutive cooling system of a vehicle.

BACKGROUND OF DISCLOSURE

Convcntional automotivc AC Systems works on vapour compression réfrigération cycle where HFC (R 134) is used as réfrigérant. Higher Global warining Potential (GWP) of R 134a gas leuding 10 to higher operating costs and higher émissions, which arc the major challenges in HFC based AC system.

Packaging of comprcssor and integrating the drive system is also critical and tedious in most of the cases. Performance of thèse types of Systems détériorâtes especially in lower vehicle speeds (city 15 traffic) as the comprcssor is driven by the engine. In many situations, AC runs in rccirculation mode which is also hannful for occupants travelling for prolongcd time and long distances.

Cabîn cooling system which works on a two stage indirect-dircct evaporative cooling principlc could bc a solution to ovcrcomc these challenges.

Indirect - direct evaporative cooling uses air-to-air heat cxchangcr to remove heat from the primary air stream without adding moisturc. In one stage, hot dry outside air is passed through a séries of horizontal tubes that arc wetted on the outside. A sccondary air stream blows over the outside of the coils and exhausts the warm, moist air to the utmosphcrc. The atmospheric air is 25 cooled without adding moisturc as it passes through the tubes.

Indirect cooling is often paired with a second direct evaporative cooling stage, to cool the supply air further whiie adding some moisturc to the supply air. Such two-stage Systems can mcct the entire cooling load for many vchiclcs run in hot and dry climatcs.

Two stage evaporative cooling Systems provide coolcr supply air at a lower relative humidity than direct evaporative coolers. The first indirect stage cools the supply air without incrcasing humidity.

Since tlie air is cooled, it has a reduced capacity to hold moisturc. The air is then passcd through a direct stage, which cools tlie air further while adding moisturc.

Further, the use of'dircct-indircct evaporative cooling system in a vchiclc is known in the art. The conventional direct-indirect evaporative cooling Systems do not fonction cfficicntly in bot soak condition of the vehîclc cabin. Tbc tenu bot soak condition used herein above is defined as the condition under which the température within the vchiclc cabin is more than the ambient température. The inefficient operation of conventional direct-indirect evaporative cooling Systems causes passenger discomfort insidc the vchiclc cabin in the hot soak condition.

In Iight of the foregoing discussion, it is ncccssary to develop an improved direct and indirect evaporative air cooling system to ovcrcomc the limitations stated above.

SUMMARY OF THE DISCLOSURE

The shortcomings ofthe prior art arc ovcrcomc and additional advantages arc provided through the provision as elaimed in the présent disclosure. Additional fcaturcs and advantages arc rcalizcd through the techniques of the présent disclosure. Other embodiments and aspects of the disclosure arc described in detail herein and arc considercd a part of the elaimed disclosure.

In an embodiment of the disclosure an automotivc cabin environment management system comprising: an enclosure, a first air filtcr mounted on top of the enclosure, wherein the first air fïltcr is configured to draw atmosphcric air. One or more air conditioning unit mounted within the enclosure, wherein tlie one or more air conditioning unit receives atmosphcric air via the first air filtcr to gcncrate conditioncd air to be supplied to a cabin of the vchicle. A plurality of second air filtcrs arc mounted below the enclosure, wherein each of the plurality of second air filtcrs arc located on cithcr sides oftlie first air filtcr and arc fluidly conimunicably attached to one ofthe one or more air conditioning unit. Further, a plurality of connecting ducts arc provided in the system, wherein each of the plurality of connecting ducts arc connected to at least one of the plurality of second air filtcrs. At least one motorized flaps arc mounted within the each of the plurality of connecting ducts, wherein the motorized flaps arc located away from the plurality of the second air filtcrs; wherein the plurality of second air filtcr, plurality of connecting ducts and at least one motorized flaps arc arranged such that, tlie plurality of connecting ducts redirects predetermined volume ofthe conditioncd air to be supplice! to the cabin back into the one or more air conditioning unit via the plurality of second air filtcrs when the motorized flaps arc in operating condition.

In un embodiment ofthe disclosure each ofthe one or more air conditioning unit comprises: one or more cvaporatîvc heat cxchangcrs of predetermined shapc, wherein the one or more evaporative heat cxchangcrs arc configured in vicinity of the first air filter to reçoive utmosphcric air via the first air filter. One or more evaporative pads arc provided in the air conditioning unit, wherein the at least one evaporative pad is placed adjacent to one or more evaporative heat cxchangcrs and is configured to rcccivc substantially conditioncd air from the one or more evaporative heat cxchangcrs. One or more blowers arc placed adjacent to the one or more evaporative pads, wherein the one or more blowers are configured lo reçoive conditioncd air from the one or more evaporative pads and supply the conditioncd air into the cabin. At least one exhaust fan placed above each of the one or more evaporative heat cxchangcrs, wherein the at least one exhaust fan cxpels hot air from the cabin to the atmosphère. Further, at least one water dispenser placed above the each of the one or more evaporative beat cxchangcrs and the each of the one or more evaporative pads, wherein the at least one water dispenser is configured to dispense water onto the each of the one or more evaporative heat cxchangcrs and the each of the one or more evaporative pads; at least one water climinator placed adjacent to the each ofthe one or more evaporative pads, wherein at least one water climinator configured to climinatc the moisturc from the conditioncd air.

In an embodiment of the disclosure plurality of air guiders located inside the each of the one or more air conditioning unit, wherein the plurality of air guiders arc configured to guide the atmosphcric air rcccived via the first air filter into the one or more evaporative heat cxchangcrs.

In an embodiment of the disclosure plurality of roof ducts connected to the enclosure, wherein the plurality of roof ducts runs through substantial length of the cabin for supplying conditioncd air.

In an embodiment of the disclosure a first water sump is provided below the cabin of the vchiclc adopted to store water, wherein the one or more evaporative beat cxchangcrs of the one or more air conditioning unit reçoives water from the first water sump.

In an embodiment of the disclosure a second water sump is provided below the cabin of the vchiclc adopted to store water, wherein the one or more evaporative pads of the one or more air conditioning unit receives water from the second water sump.

In an embodiment of the disclosure plurality of conduits arc provided at the bottom of each of the one or more evaporative heat cxchangcrs and the one or more evaporative pads within the enclosure for rccirculating the water into the first water sump and second water sump.

In another non-limiting embodiment of the disclosure thcrc is provided a method of managing an automotivc cabin environment. The method comprising steps of: receiving atmosphcric air into an one or more air conditioning unit mounted within the enclosure via a first air filtcr for conditioning the atmosphcric air, Then, rcdirccting predetermined volume of the conditioncd air to bc supplicd to lhe cabin of the vehiclc back to the one or more air conditioning unit with the hclp of plurality of connecting ducts, wherein the conditioncd air is rcdircctcd via plurality of second air filtcrs into the one or more air conditioning unit for further conditioning; wherein, conditioncd air is rcdircctcd when at least one motorized flap configured within the plurality of connecting ducts is În operating condition.

In an embodiment of the disclosure the at least one motorized flap is operated when the température of the cabin is more titan predetermined cabin température.

In an embodiment of the disclosure the predetermined cabin température ranges from 25° C to 35°C.

The foregoing summary is illustrative only and is not intended to bc în any way lïmiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will bccomc apparent by réference to the drawings and the following dctailcd description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The disclosure îtsclf, however, as well as a preferred mode of use, further objectives and advantages thereof, will best bc understood by réference to the following description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments arc now described, by way of example only, with référence to the accompanying figures wherein like réference numerals represent like cléments and in which:

FIG. la illustrâtes a longitudinal cross-scctional view of the Air conditioning unit according to an embodiment of the présent invention.

Fig. lb illustrâtes scctional views of the air conditioning unit showing the flap operations in normal and scvcrc modes.

FIG. 2 illustrâtes a lop view of lhe air conditioning unit shown in FIG. la.

FIG. 3 illustrâtes a side view of the vchiclc showing lhe schcmatic layout of water distribution System connecting the automotivc cabin environment management system and ducting arrangement.

FIG. 4a illustrâtes a rcar view of the automobile layout shown in FIG. 3 and positioning of the plurality of vents on the plurality of roof ducts.

FIG. 4b illustrâtes a schcmatic layout of réfrigérant circuit used in the disclosure.

FIG. 5 illustrâtes a front scctional view of indirect cvaporattvc heat exchanger and an isométrie view of heat exchanger plate construction.

FIG. 6 illustrâtes a couventional Psychromctric chart showing the thcrmodynamîc proccsscs of primary air stream in indirect cooling stage and direct cooling stage.

FIGS. 7a & 7b illustrâtes front scctional views of different heat exchanger configurations and vertical type indirect beat exchanger construction used in the disclosure.

FIGS. 8 & 9 are Flow charts illustrating Control logic for Motorized Flap operation and Control Logic forswitching on the Blowers.

DETAILED DESCRIPTION l he foregoing hus broudly outlincd the features and technical advantages of the présent disclosure in order that the description of the disclosure that follows may bc better understood. It should bc apprcciatcd by those skilled in the art that the conception and spécifie embodiment disclosed may bc readily utilized as a basis for modifying or designing other structures for carrying out the same purposcs of the présent disclosure. It sliould also bc rcalizcd by those skilled in the art that such équivalent constructions do not départ from lhe spirit and scope of the disclosure. The novel features which arc believed to bc charactcristic of the disclosure, both as to its organization and method of operation, together with further objccts and advantages will bc better understood from the following description when considcrcd in connection with the accompanyîng figures. It is to bc cxprcssly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a définition of lhe limits of the présent disclosure. Il will bc readily understood that the aspects of the présent disclosure, as generally described herein, and illustrated in the figures, can bc arranged, substituted, combined, and designed in a wide variety of different configurations, ail of which urc cxplicitly contcmplated and make part of this disclosure.

An automobilc/vchiclc referred licrcinabovc and below can bc a vehicie where the need of such cabin environment management system is ncccssary. For example, the vehicie is selected from group comprising but not limited to fuel cell automobiles inciuding, but arc not limited to bus, trucks, cars, clcctric powered vchiclcs, solar powered vchiclcs, fuel powered vchicles, ships, submarines, trains and the like.

FIG. la illustrâtes a longitudinal cross-scctîonal view of the air conditioning unit (l) such as but not limiting to direct and indirect evaporative air cooling system according to an embodiment of the présent disclosure. The one or more air conditioning unit (l) is mounted within an enclosure (2), which is idcally mounted on top of the roof of a vehicie (49). The top of the cnclosurc (2) is fïttcd with a first air filtcr (3) through which the atmosphcric air is drawn into the one or more air conditioning unit (l). The one or more air conditioning unit (l) consists of one or more evaporative heat exchangers (11, 12) of predetermined shape which arc placed on either side of the first air filtcr (3). The one or more air conditioning unit (l ) also consists of one or more evaporative pads (13, 14) placed adjacent to each ofthe one or more evaporative heat exchangers (11, I2). The one or more air conditioning unit (!) equipped within the enclosure (2) which lias an open area just below the first air filtcr (3). Further, pluralitics of air guiders (46,47) arc fixed to the inside of the cnclosurc (2) in such a manner so as to direct the atmosphcric air onto the one or more evaporative heat cxchangcrs (11, 12). The onc or more evaporative pads (13, 14) which arc placed adjacent to the each of the onc or more evaporative heat cxchangcrs (11, 12) receive the partially conditioncd air from the onc or more evaporative heat cxchangcrs (l l, 12) for further conditioning.

The onc or more air conditioning unit (l) is further connected to plurality of roof ducts (6, 7) which arc mountcd inside the cabin (10) of the vehicle (49). The plurality of roof ducts (6, 7) are further provided with multiple numbers of vents (8, 9) to supply conditioncd air to the cabin (10). The onc or more blowers (4, 5) placed on either side of the air conditioning unit (l) are used to supply the conditioncd air into the cubin (10), also sincc thcrc arc multiple number of compact sized onc or more blowers (4, 5) on either side of the air conditioning unit (l) the vehicle (49), uniform air flows into the rooT duels (6, 7). Hcnce, this ensurcs uniTorm air distribution to the entire vehicle cabin (10) for the same cooling capacity rcquircmcnt.

The onc or more blowers (4, 5) mountcd on each side of the air conditioning unit (l ) draws the air from atmosphère through the first air filter (3) and passes via the onc or more evaporative beat cxchungcrs (11, 12) and onc or more evaporative pads ( 13, 14). As the atmospheric air passes via the onc or more evaporative beat cxchangcrs (il, 12) and onc or more evaporative pads (13, 14), the température of the atmospheric air is gradually reduced to less than ambient température and then supplied into the cabin (I0) of the vehicle (49) through the roof ducts (6, 7) and vents (8, 9) respectivcly.

The opening area of the first air filter (3) varies from l ,5 to 2 times of total supply air openings at the onc or more blower (4, 5) outlcts on either side of the air conditioning unit (l).

In an embodiment of the présent disclosure, the onc or more blowers (4, 5) operate at different speeds with a DC supply voltage from battery system of the vehicle (49). The variable speed operation of the one or more blowers (4, 5) improves average energy efficicncy of the onc or more air conditioning unit (l) by operating at the lowest speed required by the cooling load unlikc convcntional auxiliary drive arrangement of bclt, pullcy and variable motor drive system for the blowers. The speed of the onc or more blowers (4, 5) is varied by varying the input power to the blower motors by means of variable rcsistor which is in-built in the motors. Further, each blower motor is protcctcd from water ingress and dust ingress by using compatible IP grade components, unlikc conventional large sized mctallic blower casing and impcllers, the compact blowers arc made with plastic materials.

Ambient atmospheric air is filtered in the first uir filter (3) to supply clcan and fresh air which passes vcrtically downwards initially and then rcdircctcd horizontally to the roof ducts (6, 7) and vents (8, 9), The one or more air conditioning unit (I) with the aid of plurality of air guiders (46, 47) helps in dirccting the air effectively to the one or more evaporative heat cxchangcrs (11, 12).

The suction spacc (48) available between first air filter (3) and the one or more evaporative beat cxchangcrs (11, 12) in the présent disclosurc is more than the conventional Systems by about 20% due to trapézoïdal construction of the one or more evaporative heat cxchangcrs (11, 12) and its integrated orientation. There will bc a réduction of 10% of blower noise when comparcd with conventional vertical type of one or more evaporative heat cxchangcrs construction. Different type of heat exchangcr configurations used in the présent disclosurc for indirect evaporative cooling stage is illustratcd in Fig. 7. Further, vertical type indirect heat exchangcr construction which can also bc used forsmall cooling load requircmcnts is illustratcd in in Fig. 7b.

The rcdircctcd primary air enters into the one or more evaporative heat cxchangcrs (11, 12) to undergo indirect evaporative cooling stage where it is cooled without the addition of moisturc thcrcto. The cooled primary airflow [caves the indirect cooling stage and enters the one or more evaporative pads (I3, 14) where it further undcrgocs direct evaporative cooling and the conditioncd air is supplicd to the cabin (10) of the vehicle (49). The secondary air flow from the cabin which serves to cool the primary air flow is dircctcd to the bottom of the one or more evaporative heat cxchangcrs (11, 12) through individual plurality ofsecond air filters (I7a, 17b). The secondary air flow from the cabin enters the bottom of the one or more evaporative heat cxchangcrs (11, 12) through the plurality of second air filters ( 17a, 17b) which flows vcrtically or inclincd in the indirect cooling stages and then exits to the atmosphère by means of multiple number of exhaust fans (I5, I6) placcd above the one or more evaporative heat cxchangcrs (11, 12). 100% of second air filter areas are exposed to the passenger cabin air in normal operation of the air conditioning unit and 100% of secondary air filter areas arc exposed to the primary air with the hclp of at least one motorized flaps (41,42, 50, 51 ) and plurality of connecting ducts (43,44).

During normal operating condition, the plurality of second air filtcrs (I7a, 17b) serve for tlic air coming from the cabin (10) of the vchiclc (49). During hot soak orscvcrc operating condition, the plurality of second air filtcrs (I7a, 17b) serves to prc-cool the primary air by passing partial cold air from tlic roof ducts (6, 7) into vertical channcls of the one or more evaporative beat exchangcrs 5 (ll,l2).

In the présent disclosure, there arc two separate liquid storage sumps, namcly first water sump (l 8) to supply water to the one or more evaporative heat cxchangers (11, 12) for indirect evaporative cooling stage and second water sump ( 19) supplies water to the one or more evaporative pads (13, 10 14) for direct evaporative cooling. The first water sump (18) and the second water sump (19) arc installcd under the cabin floor (34) of the veliicle (49) al a level of accessibility to service.

FIGs 3,4a and 4b, illustrâtes second water sump ( 19) mounted at a slightly higher position than the first water sump (18) and both arc connected with a pipe to allow the water from the second water I5 sump (19) to the first water sump ( 18). Further, a manual valve (56) and a float (57) arrangement are provided inside the first water sump (I8) to allow certain amount of water from the second water sump (19) whenever required. Manual valve (56) is normally closed valve and this can bc operated manually whenever there is a déficit of water în the first water sump (18). Otherwise thèse two water sumps arc independent in rcgular operation.

There arc four individual auxiliary sumps (20, 2I, 22, 23) provided with sloping walls in the cnclosurc (2) of the air conditioning unit (l) to facilitatc water drainage from the one or more evaporative heat cxchangers and one or more evaporative pads (11, 12 and 13, 14) during cooling stages and then rcturned to the water sumps (18, 19). The first water sump (18) serves as a water 25 réservoir for the one or more evaporative heat cxchangers (11, 12) in indirect cooling stages and water is circulatcd through water filter (24), recirculating pump (28), water dispenser (30, 31) auxiliary sumps (20, 2l) water filter (25) which arc in turn connected with lhe flexible water pipes.

Further, the first water sump (18) is also connected with a réfrigérant circuit to cool tlic water inside the sump and supply chillcd water to the one or more evaporative heat cxchangers (11, 12) 30 during indirect cooling stuges.

Further, the second water sump (19) serves as a water réservoir for the one or more evaporative pads (13, 14) during direct cooling stages and water is circulatcd through water filter (26), rccirculating pump (29), water dispensers (32, 33), auxiliary sumps (22, 23), water filter (27) which arc in turn connected with the flexible water pipes. The pump (28) feeds the water at top portion of the one or more evaporative beat cxcliangcrs (II, 12) during the indirect cooling stages for the wet passages through the water dispensers (30, 31). Water retumed from the auxiliary sumps (20, 21) is circulatcd down to the first water sump (18) through the water filter (25). The pump (29) feeds the water at top portion of the one or more evaporative pads (13, 14) during direct cooling stages through the water distributors (32,33). Water returned from the auxiliary sumps (22, 23) is circulatcd down to the second water sump (19) through the water filter (27).

FIG. 5 illustrâtes a cross sectional view of tlic heat cxchangcr arrangement of the indirect cooling stages shown in FIG.la. The one or more evaporative beat cxchangcrs (11, 12) arc mirror images in construction which arc mounted on the Left Hand (LH) and Right Hand (RH) side of the one or more air conditioning unit (I). The indirect stage heat cxchangcr is dividcd into a first set of passages (36) for the primary air flow from the atmosphère, and second set of passages (37) for the secondary air from cabin (10). Second set of passages (37) arc treated with non-woven material to cnhancc wettability. Water is conveyed by water dispenser (30, 31) in inclincd or vertical direction in the secondary passages (37) to wet the surfaces of lhe heat cxchangcr plates (38). Secondary air from the cabin (10) flows through the secondary passages (37) and cvaporativcly cools the secondary heat cxchangcr plates (35). Mcanwhile, the primary airflow travelling through the first set of passages (36) is cooled by contact with the surfaces of the cooled heat exchange plates (35). Primary air flow is cooled in this manner without adding any moisture which is known as sensible cooling. The scnsibly cooled primary air leaves the one or more evaporative heat cxchangcrs (11, 12) during the indirect cooling stages and is further cooled in lhe one or more evaporative pads (13, 14) during the direct cooling stages. The direct evaporative cooling stage includcs un evaporative medium which includes a wetted pad or perméable medium, to cvaporativcly cool the primary air flow.

Referring back to FIG. lu, which illustrâtes auxiliary sumps (20,21, 22, 23) are positioncd slightly inclincd approximateiy at an angle 5° to ensurc the draincd water from indirect and direct cooling stages are directed to the respective first and second water sumps (18, 19). At least one water eliminators (39, 40) provided after the direct cooling stages to climinatc the water droplcts before passing to the one or more blowers (4, 5) and then to roof duels (6, 7).

FIG. 4a illustrâtes the rcar view of roof duct and vents arrangement. The outlets on the air conditioning unit (l ) arc connected to the roof ducts (6, 7) respectively. One or more blowers (4, 5) throws the cold air to the roof ducts (6, 7) and then to the cabin (I0) by the multiple number of vents (8,9).

FIG. 3 illustrâtes side view of the duct arrangement inside the vehicle (49). The air conditioning unit (l) is mounted at the centre of the vehicle (49). The outlets of the air conditioning unit (I) arc connected to the roof ducts (6, 7) which arc mounted along the vehicle (49). The cold air from one or more blowers (4, 5) passes into the ducts vcrtically downwards then distributed to the front and rcar sides of the duct. Air vents (8, 9) arc mounted at the bottom and side of both roof ducts (6, 7) to supply cold air to the passenger cabin ( 10). Further the vents (8, 9) arc not provided at sides, where the cabin (10) sccondary air is exhausted to the atmosphère to avoid cold air short circuiting.

As shown in FIG. I a, there arc connecting duct arrangements (43,44) between the roof ducts (6, 7) and plurality of second air filtcrs (I7a, i 7b) which arc exposed till the lcngth of the second air filtcrs zone. Two motorized flap arrangements (41, 42) are provided on the duct ends and another two motorized flap arrangements (50, 5I) are provided on the plurality of second air filter (17a, 17b) ends. Ail these flaps will bc operated based on control logic. As shown in FIG. la and FIG. 2, the exhaust fans (15, 16) arc mounted on the enclosure (2) of the uir conditioning unit (1) locutcd above the one or more evaporative heat cxchangcrs (11, 12) during indirect cooiing stages to exhaust the moist air through the sccondary air passages of the one or more evaporative beat cxchangcrs (11, 12) to the atmosphère. Speed of the exhaust fans (15, 16) can bc varied accordingly and hence exhaust air quantity can bc controlled by varying the input power to the fan motors by means of variable rcsîstor which is in-built in the motors.

FIG. 1b illustrâtes the primary air and sccondary air flow paths and the motorized flap positions during normal operation mode and scvcrc operation mode of the air conditioning unit (1).

In normal mode of operation i.e., when cabin température is not more than ambient by 5°C, at least one motorized flaps (41,42, 50, 51) arc remained in closcd condition, 100% of the cold air which is eoming oui from the air conditioning unit (I) is delivered to the cabin to bc cooled. In this condition, since 100% of sccondary air is being taken from the cabin (10) of the vehicle (49), the air température passing through the inclined or vertical channels of the one or more evaporative heat cxchangcrs (11, 12) arc lcsscr than the ambient température and this température would bc sufficîcnt to cool the non- woven web material on secondary channel surfaces (35). This nonwoven web material is wct duc to the water sprayed from the water dispensers (30, 31 ) at top. The primary air passing through the horizontal channels are scnsibly cooled whcrcas secondary air in inclined or vertical channels is exhausted as hot and moist air to the atmosphère by exhaust fans (15, 16) mounted on top.

In scvcrc mode of operation, i.e., if the vchiclc is hot soakcd under solar load, the cabin température may rcach at least 5°C more than the ambient température. Primary cold air from the connecting roof duels (6, 7) is partially diverted to the secondary air fillcrs (17a, 17b) so as to keep secondary wall températures colder to hâve faster cooling down of primary air from atmosphère.

In an embodiment of the présent disclosure, at least 20% of total primary cold air is passed through the plurality of connecting ducts (43, 44) to the secondary channels (37) of the one or more evaporative heat cxchangcrs (11, 12) when the at least one motorized flaps (41, 42) (mounted on duct end) and (50, 51) (mounted on secondary air filtcrs end) arc in open position, altematively referred as operating condition. The at least one motorized flaps (41,42, 50, 51) arc operated based on the controi logic defined between cabin and ambient températures. The flaps rcmains in open condition until cabin température satisfïcs the logic defined in FIG. 8. It is also provided in the controi logic that the exhaust fans (15, 16) rcmains in OFF condition until ail flaps arc elosed.

FIG. 8 illustrâtes a Flow chart which cxplains the controi logic to bc followed to operate the at least one motorized flups (41, 42, 50, 51) and exhaust fans (15, 16). As shown in the logic, if the cabin température is 5°C greater than the ambient température, the exhaust fans (15, 16) arc switchcd off and the at least one motorized flaps (41, 42, 50, 51) are opened. The one or more blowers (4, 5) arc switchcd ON to supply major amount of air approximatcly around 80% to the roof ducts (6, 7), and rcmaining amount of air approximatcly around 20% of air for secondary passage of the indirect cooling stage. Now, if the température drop between ambient and cabin is lcsscr than I5°C, the cycle is repeated from first, clsc the at least one motorized flaps (41,42, 50, 51) arc elosed and the exhaust fans (15, 16) arc iurncd ON to take away the moisturc air to the atmosphère. The one or more blowers (4,5) continue to run after ensuring the flaps arc fully elosed.

FIG. 9 illustrâtes a Flow chart which cxplains the control logic to bc followed bcforc switching on the one or more blowers (4, 5) in normal operation. The system is switchcd ON and the water level in the second water sump (19) is chcckcd, if the water level is low, makeup water is uddcd until maximum water level is rcachcd. The water level in the first water sump (18) is chcckcd, if the water level is low, makeup water in the first water sump (18) is added until maximum water level is rcachcd. The direct cooling stage pump (29) is switchcd on for around 4-6 minutes preferably 5 minutes. The indirect cooling stage pump (28) is switchcd ON after 5 minutes. The at least one motorized flaps (41,42, 50, 51) are closcd and the exhaust fans (15, 16) arc switchcd ON for I - 3 minutes preferably 2 minute to exhaust the hot cabin air out, The one or more blowers (4, 5) arc switchcd ON to supply 100% air lo the roof duels (6, 7).

Control panel (45) is mounted in the driver zone to monilor the passenger cabin comfort condition and also for trouble shooting of the system (diagnostics). Driver can set the desired cabin température. Température sensors arc provided inside and outside the cabin (10). Sensors provided ΐη both first and second sumps (18, 19) to continuously verify the water level and shows an indicator on control panel (45) which is mounted at driver area, When the water level reaches to a minimum level there will bc a reminder shown on control panel (45) to top up the makc-up water.

FIG. 6 illustrâtes the primary air conditions undergoing different thermodynamie proccsscs on a conventional psychromctric chart. Point 1 refers lhe primary filtered air condition bcforc entering the indirect cooling stage. Point 2 refers the scnsibly cooled primary air condition after indirect cooling stage where there is no moisturc addition. Point 3 refers the adiabatically cooled primary air condition after direct cooling stage which is supplicd to the roof duels (6, 7).

FIG .4b illustrâtes the réfrigérant circuit attached to the first water sump (18) as optional to supply chillcd water to the indirect one or more evaporative beat cxchangcrs (11, 12) as per the cabin cooling rcquircmcnts. The réfrigérant circuit consists of a comprcssor (52), condenser (53), expansion valve (54) and a chiller heat exchanger (55). A small sized comprcssor (52) is belt driven from the engine crank pullcy. When réfrigérant circuit is cnablcd by giving the request in a separate control panel, the chiller heat exchanger (55) which is submerged inside the first water sump (18) cools the surrounding water which is intended to supply for indirect cooling stages ut the one or more evaporative beat cxchangcrs (11, 12). The réfrigérant circuit is best utilized during hot and humid ambient conditions. Direct cooling stages at the one or more evaporative pads (13, 14) (cooling and humidification) are disabled by switching of the water pump (29) and only indirect cooling stages (11, 12) (sensible cooling) arc cnablcd to providc cooling for the cabîn space without adding any moisturc. Further cfficiency of the air conditioning unit (1) is improved duc to reduced power consumption since water pump (29) is off.

As cxplained a typical bus rcquircs one or more air conditioning units (1), one for LH side passengers, another one for RH side passengers due to higher heat loads. A single air conditioning unît (1) can also bc used in typical trucks, vans and any passenger cars or any moving vehicles with a single blower or multiple blowers along with compatible ducting arrangement.

In another embodiment of the présent disclosure, multiple modules of air conditioning unit (1 ) can also bc used in any moving vehicles including Fuel Cell bus where water is the end product as an outcomc of chemical réactions. This water can bc directly used as make up water for the said air conditioning unit (1).

Air conditioning unit (1) used in this disclosure is the system which removes the sensible beat from the cabin (10) and also maintains humidity levels up to acceptable range especially for hot and dry climatic conditions.

ADVANTAGES

Two stage evaporative Systems in comparison to convcntional single stage evaporative coolcrs can hâve more cooling capacity. These units do not use a réfrigérant comprcssor and are thus significantly more energy efficient than convcntional AC Systems. The units add less moisturc to the conditioner! space and always work on fresh air there by providing bclter indoor environment and comfort of occupants. Further operating cost of these Systems arc far lesscr than convcntional réfrigérant based AC Systems duc to absence of comprcssor. Since these units do not use any CFC. HCFC, HFC based réfrigérants, provides 100% ozone sufe. The cabin température can bc droppcd to I5°C and can bc achieved within 10 minutes with respect to the ambient condition în normal mode of operation. Motorized flap arrangement hclps in rcducing cabin température by 20°C from ambient température within 10 minutes especially in a hot soak condition of lhe vchiclc.

The air conditioning unit of the présent disclosure improves the passenger comfort in the vchiclc, even when the vchiclc is in hot soakcd condition.

The air conditioning unit of the présent disclosure, has 10 % reduced operating noise when 5 comparcd with that of the prior arts.

REFERRAL NUMERALS

Rcfcrral Numéral	Description
100	Automotive cabin environment management system
1	Air conditioning unit
2	Enclosure
3	First air filter
4,5	Blowers
6,7	Roof ducts
8,9	Vents
10	Cabin
11. 12	Evaporativc heat cxchangcrs
13, 14	Evaporativc pads
15, 16	Exhaust fans
17a, 17b	Second air filters
18	First water sump
19	Second water sump
20,21,22, 23	Auxiliary sumps
24, 25,26,27	Water filters
28,29	Recirculating pumps
30,31,32,33	Water dispensers
34	Cabin floor
35	Secondary channel surfaces
36	First passages
37	Second passages

38	Primary surface of Heat cxchangcr plates
39,40	Water climinators
41,42, 50,51	Motorizcd flaps
43,44	Connecting ducts
45	Control panel
46,47	Air guiders
48	Suction spacc
49	Vehicle
52	Comprcssor
53	Condenser
54	Expansion valve
55	Chili heat cxchangcr
56	Manual valve
57	Float

EQUIVALENTS

With respect to the use of substantially any plural and/or singular tcrms herein, those having skill 5 în the art can translate from the plural to the singular and/or from the singular to tlic plural as is appropriate to the contcxt and/or application. The various singular/plurai permutations may bc cxprcssly set forth herein for sakc of clarity.

It will bc understood by those within the art that, in general, tcrms used herein, and especially in 10 the appended claims (e.g., bodics of the appended claims) arc generally intended as open” tcrms (e.g., the term “induding” should bc interpreted as “induding but not limited to,” the term “having” should bc interpreted as “having at least,” the term “includes” should bc interpreted as “indudes but is not limited to, etc.). It will be further understood by those within the art that if a spécifie number of an întroduccd claim récitation is intended, such an intent will bc cxplicitly 15 rccitcd in the claim, and in the absence of such récitation no such intent is présent. For exampie, us un aîd to understanding, the following appended claims may contuin usuge of the introductory phrases “at least onc” and “one or more” to introducc claim récitations. Howcvcr, the use of such phrases should not bc construcd to imply that the introduction of a daim récitation by the indcfinitc articles “a” or “an” limits any particuiar claim containing such introduced claim récitation to inventions containing only one such récitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefînîte articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “al least one or “one or more”); the same holds truc for the use of definite articles used to introducc claim récitations. In addition, even if a spécifie number of an introduced claim recitation is explicitly recitcd, those skilled in the art will rccognizc that such récitation should typically be interpreted to mcan at least the rccited number (e.g., the barc récitation of “two récitations,” without other modifier», typically means at least two récitations, or two or more récitations). Furthcrmorc, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intendcd in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to Systems that hâve A alonc, B alonc, C alonc, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc. is used, in general such a construction is intendcd in the sense one having skill in the art would understand the convention (c,g„ “a system having at least one of A, B, or C” would include but not bc limited to systems that hâve A alonc, B alonc, C alonc, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will bc further understood by those within the art that virtually any disjunctivc word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should bc understood to contcmplatc the possibilitics of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will bc understood to include the possibilitics of “A” or “B” or “A and B.”

In addition, where fcuturcs or aspects of the disclosure arc described in terms of Markush groups, those skilled in the art will rccognizc that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

While various aspects and embodiments hâve been disclosed herein, other aspects and embodiments will bc apparent to those skilled in the art. The various aspects and embodiments disclosed herein arc for purposcs of illustration and arc not intendcd to bc limiting, with the truc scopc and spirit being indicatcd by the following claims.

Claims (11)

1. WE CLAIM:

   1. An automotivc cabin environment management System (100) comprising:

   an enclosurc (2);

   a first air filer (3) mounted on top of the enclosurc (2), wherein the first air filter (3) is configured to draw atmosphcric air;

   one or more air conditioning unit (1) mounted within the enclosurc (2), wherein the one or more air conditioning unit (1) reçoives atmosphcric air via the first air filter (3) to gcncratc conditioncd air to bc supplicd to a cabin (10) of the vchicle (49);

   plurality of second air filters (17a, 17b) arc mounted below the enclosurc (2), wherein each of the plurality of second air filters (17a, 17b) arc located on cither sides of the first air filter (3) and are fluidly communicably attached to one of the one or more air conditioning unit (I );

   plurality of connecting ducts (43, 44), wherein each of the plurality of connecting ducts (43, 44) are connected to at least one ofthe plurality ofsecond air filters (17a, 17b);

   at least one motorized flaps (41, 42, 50, 51) arc mounted within the each of the plurality of connecting ducts (43, 44), wherein the at least one motorized flaps (41, 42, 50, 51) arc located away from the plurality of the second air filters (17a, 17b);

   wherein the plurality of second air filters (17a, 17b), plurality of connecting ducts (43, 44) and at least one motorized flaps (41,42, 50, 51) arc arranged such that, the plurality of connecting ducts (43, 44) redirects predetermined volume of the conditioncd air to bc supplicd to the cabin (10) back into the one or more air conditioning unit (1) via the plurality of second air filters (17a, 17b) when the at least one motorized flaps (41, 42, 50, 51) are in operating condition.
2. 2. The automotivc cabin environment management System (100) as claimed in claim 1, wherein each of the one or more air conditioning unit (1 ) comprises:

   one or more evaporative heat exchangcrs (11, 12) of predetermined shape, wherein the one or tnorc evaporative beat exchangcrs (11, 12) are configured in vicinity of the first air filter (3) to receive atmosphcric air via the first air filter (3);

   one or more evaporative pads (13, 14), wherein the at least one evaporative pad (13, 14) is placed adjacent to one or more evaporative heat exchangcrs (11, 12) and is configured to rcccivc substantîally conditioncd air from the one or more evaporative heat cxchangcrs (11, 12);

   one or more blowers (4, 5) arc placed adjacent to the one or more evaporative pads (13, 14), wherein the one or more blowers (4, 5) arc configured to receive conditioncd air from the one or more evaporative pads (13, 14) and supply the conditioncd air into the cabin (10);

   at least one exhaust fan (15, 16) placed above each of the one or more evaporative heat cxchangcrs (11, 12), wherein the at least one exhaust fan (15, 16) cxpcls hot air from the cabin (10) to the atmosphère;

   at least one water dispenser (30, 31, 32, 33) placed above the each of the one or more evaporative heat cxchangcrs (11, 12) and the each of the one or more evaporative pads (13, 14), wherein the at least one water dispenser (30, 31, 32, 33) is configured to dispense water onto the each of the one or more evaporative heat cxchungers (11, 12) and the each of the one or more evaporative pads (13, 14);

   at least one water climinator (39, 40) placed adjacent to the each ofthe one or more evaporative pads (13, 14), wherein at least one water climinator (39, 40) configured to climinatc the moisturc from the conditioncd air.
3. 3. The automotivc cabin environment management system (100) as elaimed in claim 1 comprises plurality of air guîdcrs (46, 47) located insidc the each of the one or more air conditioning unit (1), wherein the plurality of air guiders (46, 47) arc configured to guide the atmosphcric air received via the first air filtcr (3) into the one or more evaporative heat cxchangcrs (11, 12).
4. 4. The automotive cabin environment management system ( 100) as elaimed in claim 1 comprises plurality of roof ducts (6,7) connected to the enclosure (2), wherein the plurality of roof ducts (6, 7) runs through substantial length of the cabin ( 10) for supplying conditioncd air.
5. 5. The automotivc cabin environment management system (100) as elaimed in claim 1 comprises a first water sump (18) provided below the cabin (10) of the vchiclc (49) adopted to store water, wherein the one or more evaporative heat cxchangcrs (11,12) of the one or more air conditioning unit (1) receives water from the first water sump (18).
6. 6. The automotive cabin environment management system ( 100) as elaimed in claim l comprises a second water sump (19) provided below the cabin (10) of the vchiclc (49) adopted to store water, wherein the one or more evaporative pads (l 3, 14) of the one or more air conditioning unit (l ) reçoives water from the second water sump (l 9).
7. 7. The automotive cabin environment management system ( 100) as elaimed in claim l comprises plurality of conduits (20, 2I, 22, 23) provided at the bottom of each of the one or more evaporative heat cxchangcrs (11, 12) and the one or more evaporative pads (l 3, I4) within the enclosure (2) for rccirculating the water into the first water sump ( 18) and second water sump (19).
8. 8. A method of managing an automotive cabin environment comprising steps of:

   receiving atmosphcric air into an one or more air conditioning unit ( l ) mounted within the enclosure (2) via a first air filter (3) for conditioning the atmosphcric air;

   redirccting predetermined volume of the conditioncd air to bc supplicd to the cabin (10) of the vchiclc (49) back to the one or more air conditioning unit (l) with the hclp of plurality of connecting ducts (43,44), wherein the conditioncd air is rcdircctcd via plurality of second air filtcrs (I7a, 17b) into the one or more air conditioning unit (l) for further conditioning;

   wherein, conditioncd air is rcdircctcd when at least one motorized flap (41,42, 50, 51) configured within the plurality of connecting ducts (43,44) is in operating condition.
9. 9. The method of managing an automotive cabin environment as elaimed in claim 8, wherein the at least one motorized flap (41,42,50,51) is operated when the température of the cabîn (10) is more than predetermined cabin température.
10. 10. The method of managing an automotive cabin environment as elaimed in claim 10, wherein the predetermined cabin température ranges from 25° C to 35°C.
11. 11. A vchiclc comprising an automotive environment management system as elaimed in claim l.