Automatic displacement ventilation system with heating mode

Displacement ventilation systems are generally poor performers when it comes to heating. The instant patent application discusses devices and systems for improving heating performance while retaining the benefits of displacement ventilation without wholesale co-location of independent space conditioning systems.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1Billustrates a conditioned space with configurable mixing/displacement ventilation registers in displacement and mixing modes, respectively.

FIGS. 2A and 2Billustrate a first embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.

FIGS. 3A and 3Billustrate a second embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.

FIGS. 4A and 4Billustrate a third embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.

FIGS. 5A and 5Billustrate a fourth embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.

FIGS. 6A and 6Billustrate a fifth embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.

FIGS. 7A and7B illustrate a sixth embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.

FIGS. 8A and 8Billustrate an alternative embodiment in which the return registers are changed over from heating to cooling mode, but the supply registers are the same.

FIGS. 9A and 9Billustrate an alternative embodiment in which the return registers are changed over from heating to cooling mode, and hydronic heating is used in place of force air heating.

FIG. 10is an illustration of a central control system that may be used with various embodiments discusser herein.

FIG. 11shows a plan view of a room with multiple discharge registers1125,1135, and1145.

FIGS. 12A and 12Bshow an embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively, in which independent dampers are used to modulate total air volume, for example based on a V A V scheme.

FIG. 13illustrates a simple example of a controller for V A V control as well as mode switching for a configurable mixing/displacement ventilation register such as illustrated atFIGS. 12A and 12B.

These figures are intended to show the concept and are not intended to show details of components whose designs are well understood in the field such as linkages, motor, details, bearings, supports, etc. These are within the competence of skilled practitioners and are not discussed in detail herein.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1AandFIG. 1Billustrates a configurable mixing/displacement ventilation register550in an occupied room570. People510in the room are warmer than the surrounding air, causing air to rise by convection. The room also contains a cooling-mode return register530in the upper portion of the room, and a heating mode return register535in the lower portion of the room. The temperature of the air within the room570is illustrated by isothermal layers of constant temperature air505.

When the room is in displacement mode, which is generally used for cooling the conditioned space, the mixing/displacement ventilation register550supplies cooled air at a low velocity from a relatively high portion and over a relatively large face area of the mixing/displacement ventilation register550. This cool air flows along the lower portion of the room. Any heat source within the room such as the occupants510, causes air warmed by that source to rise by convective forces resulting in warm zones indicated by dips in contours of constant temperature515. This rising air draws fresh cool air pooled near a floor521to replace the polluted and stale air surrounding the occupants510. The warm air pools near the ceiling and is withdrawn by the return register530. The higher regions of the room570remain relatively undisturbed and since it is not within the lower part of the room—the inhabited space—the air in contact with and breathed by occupants is relatively fresh. By not cooling this uninhabited space, the cooling efficiency is increased. Also, the immediate replacement of air polluted by heat sources increases comfort.

FIG. 1Billustrates the mixing mode for heating the occupied space. In this mode, the mixing/displacement ventilation register550supplies heated air at a high velocity through a relatively small face area as illustrated by jets551. This warm air flows rapidly along the lower portion of the room before it has time to rise from convection and encourages mixing of all the air in the room, as indicated by the randomly arranged and directed arrows552. This rapid movement causes mixing of the air in the room due to the initial velocity of the jets551, their turbulence, and the tendency of the heated air naturally to rise due to convection. The heating mode return register535removes cooled air which tends to sink from convection.

FIGS. 2A and 2Billustrate a first embodiment of a configurable mixing/displacement ventilation register550in displacement and mixing modes, respectively. Referring now toFIG. 2Athe first embodiment of a configurable mixing/displacement ventilation register550is in displacement, or cooling, mode. As the cool air160enters the ventilation register plenum130it causes a thermal actuator105to move a thrust rod110attached to a baffle cage115toward a lower section120of the configurable mixing/displacement ventilation register550, thereby moving it to the floor base150of the configurable mixing/displacement ventilation register550. The baffle cage115allows air to pass through it and serves to spread the flow over the large face area that includes a larger baffle housing100of the configurable mixing/displacement ventilation register550. The open area of the baffles100and115is such as to cause resistance across the face of the baffles100and115thereby spreading the incoming flow160broadly over the face area of the baffles110and115. This results in flow over the majority of the outer diffusion baffle100of the configurable mixing/displacement ventilation register550as indicated by arrows145. The air flowing from the baffle cage115and the baffle housing110therefore functions as displacement supply register venting air at a low velocity through relatively restrictive openings in the baffles of the baffle housing100and the baffle cage115.

FIG. 2Billustrates the first embodiment in mixing, or heating, mode. As the warm air165enters the ventilation register plenum135it causes thermal actuator105to move the baffle cage115upwardly to uncover an open outlet120of the configurable mixing/displacement ventilation register550. A bottom116of the baffle cage115has a high percentage open area and provides little resistance to flow as does the open outlet120. As a result, a direct flow path through the plenum135to the open outlet120is created which results in low restriction—high velocity—flow of the warm air to the open outlet120. Thus, most of the heating air165passes at a relatively high velocity out the lower, relatively small face area of the open outlet120of the configurable mixing/displacement ventilation register550. Thus, in the present configuration, it functions as a mixing supply register.

FIGS. 3A and 3Billustrate a second embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.FIG. 3Aillustrates the second embodiment of the configurable mixing/displacement ventilation register551in displacement, or cooling mode. A transmission15is indicated figuratively by a broken line. The transmission may be formed by any suitable means such as a pulley or gear system or by means of pushing or pulling or other rotating members. The details are outside the scope of invention and are readily created for various design arrangements.

As cool air160enters a ventilation register plenum230it causes the thermal actuator10, by way of the transmission15, to rotate a spring loaded capstan220which releases tension on a chord225allowing a spring-loaded cap plate210to pivot on an axis of the capstan/lever215to seal the end212of the ventilation register plenum230. Cool air flow270is forced to spread the flow over the large face area of a flow-restricting baffle250and further distributed by an outer baffle260. The capstan220also releases tension on a lower pull cord235releasing a spring loaded baffle panel245to pivot on a spring-loaded axel240, securing it flush with the outer baffle260of the configurable mixing/displacement ventilation register551.

Note that the transmission15and the pulley and capstan components are shown for illustration purposes only and can be replaced by any suitable mechanism for performing the described functions. These mechanisms could be mechanical or electromechanical and performed by means of a thermoactuator such as a wax motor or a linear actuator powered by electricity or pneumatic power or controls. There are many possible design variations and the details are unimportant for understanding the invention so they are not discussed at length here. Note also that the views of the present, foregoing, and further embodiments below are section views of suitable enclosures. They can be rectangular or other shapes. The materials used may be any combination of metal, plastic, or other materials suitable for conveying air.

The resulting configuration illustrated inFIG. 3Aallows the cool air165to flow through the outer baffle260of the configurable mixing/displacement ventilation register551in the manner of a displacement supply register. The open area of the baffle260is such as to cause resistance across the face of the baffle260and the baffle panel245thereby spreading the flow160broadly over the outer baffle260face area of the configurable mixing/displacement ventilation register551as indicated by arrows265. It therefore functions as displacement supply register, venting air at a low velocity through relatively restrictive openings of the outer baffle260and the baffle panel245.

FIG. 3Billustrates the second embodiment of the configurable mixing/displacement ventilation register551in mixing, or heating mode. As the heated air165enters the ventilation register plenum230it causes the thermal actuator10to act through the transmission15to rotate the spring-loaded capstan220, exerting tension on the cap plate pull cord225causing the spring-loaded cap plate210to pivot on the axel215and open the end212of the plenum230. The capstan220also exerts tension on the lower pull cord235causing the spring loaded baffle panel245to pivot on the axis240, opening the lower portion of the configurable mixing/displacement ventilation register551. As a result, most of the heated air165passes at a relatively high velocity out the lower, relatively small face area of an open outlet243of the configurable mixing/displacement ventilation register551so that it functions as a mixing supply register.

FIGS. 4A and 4Billustrate a third embodiment of a configurable mixing/displacement ventilation register552in displacement and mixing modes, respectively.FIG. 4Aillustrates the third embodiment of the configurable mixing/displacement ventilation register552in the displacement, or cooling, mode. As the cool air160enters the ventilation register plenum330it causes the thermal actuator10to act upon the transmission15to rotate a spring loaded capstan320which releases tension on a chord325allowing a spring-loaded cap plate310to pivot on an axis of capstanllever315to seal the end312of a plenum330. Cool air flow370is forced to spread over the large face area of a flow-restricting baffle350. The capstan320also releases tension on a lower pull cord335releasing a spring loaded baffle panel345to pivot on an axel340, securing it flush with an outer baffle304of the configurable mixing/displacement ventilation register552. The releasing of the spring loaded baffle panel345also releases tension on a third pull chord345allowing a sliding baffle panel306to align with the outer baffle304allowing a cool air flow370flow through the large face area of the two baffle panels304and306which combine to form a single open baffle or grate322A.

The resulting configuration illustrated inFIG. 4Aallows the cool air160to flow through the baffle/grate322A of the configurable mixing/displacement ventilation register552in the manner of a displacement supply register. The open area of the baffle/grate322may be such as to cause substantial or little resistance across the face of the baffle/grate322. The spreading of the flow may be provided by the inner baffle350or the outer baffle/grate322may assist by providing some resistance as well. By spreading the flow broadly over the face area of the configurable mixing/displacement ventilation register552as indicated by the arrows365, it functions as displacement supply register.

FIG. 4Billustrates the third embodiment of the configurable mixing/displacement ventilation register552in mixing, or heating, mode. As the heated air165enters the ventilation register plenum330, it causes the thermal actuator10to act upon the transmission15to rotate the spring loaded capstan320causing it to exert tension on the cap plate pull cord325. This causes the spring-loaded cap plate310to pivot on the axel315and open the end of the plenum330. The capstan320also exerts tension on the lower pull cord335causing the spring loaded baffle panel345to pivot on the axis340, opening the lower portion of the configurable mixing/displacement ventilation register552. The pivoting of the spring loaded baffle panel345also removes tension on the third pull chord345allowing the sliding baffle panel306to close the baffle/shutter322preventing the warm air flow330from passing through it. The heated air165thus passes at a relatively high velocity out the lower, relatively small face area of an open outlet343of the configurable mixing/displacement ventilation register552so that the configurable mixing/displacement ventilation register552functions as a mixing supply register.

FIGS. 5A and 5Billustrate a fourth embodiment of a configurable mixing/displacement ventilation register553in displacement and mixing modes, respectively.FIG. 5Aillustrates the displacement, or cooling mode. As the cool air160enters a ventilation register plenum425it causes a rotating a thermal actuator capstan450to act upon a pull chord455to rotate a spring loaded flap cover440on a pivot460to seal off plenum430. This action causes the cooled air160to enter only a cooling plenum405which is separated from a heating plenum430by a middle wall435. The open area of the baffle404is such as to cause resistance across the face of the baffle404thereby spreading the flow160broadly over the large face area of the configurable mixing/displacement ventilation register553. This causes it to function as a displacement supply register venting air at a low velocity over a large area.

FIG. 5Billustrates the fourth embodiment of the configurable mixing/displacement ventilation register553in mixing, or heating, mode. As the warm air165enters the ventilation register plenum425it causes the rotating thermal actuator capstan450to act upon the pull chord455to rotate the spring loaded flap cover440on the pivot460to seal off the cooling plenum405. This action causes the warm air165to enter only the warm plenum430which is bound by the middle wall435and a back wall420. The relatively smaller face area of a heating mode outlet475builds greater back pressure within the warm (heating) plenum430causing the flow160to exit through the small face area of the outlet475of the configurable mixing/displacement ventilation register553at high velocity. As a result, the register553functions as a mixing supply register.

FIGS. 6A and 6Billustrate a fifth embodiment of a configurable mixing/displacement ventilation register554in displacement and mixing modes, respectively.FIG. 6Aillustrates the fifth embodiment in displacement, or cooling, mode. As the cool air160enters a ventilation register a plenum630it causes the thermal actuator10to act upon a push rod620to rotate a cap plate610on a pivot615to seal the end of the plenum630. Cool air flow665is forced to spread over the large face area of a flow-restricting inner baffle650and into a cooling plenum605. The movement of the cap plate610also releases tension on a lower baffle panel645to pivot on an axel640, securing it flush with an outer baffle604which forces a cool air flow665to spread over the large face area of a flow-restricting baffle604.

The resulting configuration illustrated inFIG. 6Aallows the cool air630to flow through the flow-restricting inner baffle650then an outer baffle604of the configurable mixing/displacement ventilation register554in the manner of a displacement supply register. The open area of the baffle604is such as to cause resistance across the face of the baffle604and lower baffle panel645thereby spreading the flow665broadly over the face area of the configurable mixing/displacement ventilation register554as indicated by the arrows665and therefore functions as displacement supply register venting air at a low velocity through relatively restrictive openings within the outer baffles604and the baffle panel645.

FIG. 6Billustrates the fifth embodiment of the configurable mixing/displacement ventilation register554in mixing, or heating mode. As the heated air165enters the ventilation register plenum630it causes the thermal actuator10to act upon the push rod620to rotate the cap plate610on the pivot615to open the end of the plenum630. This causes engagement of the cap plate610and a lever arm655of the baffle panel645to swing the baffle panel645in an open position, opening the lower portion of the configurable mixing/displacement ventilation register554. As a result, the heated air165passes at a relatively high velocity out the lower, relatively small face area of an open outlet643of the configurable mixing/displacement ventilation register554so that it functions as a mixing supply register.

FIGS. 7A and7B illustrate a sixth embodiment of a configurable mixing/displacement ventilation register in displacement and mixing modes, respectively.FIG. 7A illustrates the sixth embodiment in displacement, or cooling, mode. Note the present embodiment is similar to the embodiment ofFIGS. 6A and 6Bso many of the reference numerals are common. As the cool air160enters the ventilation register plenum630it causes the thermal actuator10to act upon the push rod620to rotate the cap plate610on the pivot615to seal the end of the plenum630. The cool air flow160is forced to spread over the large face area of the flow-restricting inner baffle650and into the cooling plenum605. The resulting configuration illustrated inFIG. 7A allows the cool air630to flow through the flow-restricting inner baffle650then the very open outer baffle700of the configurable mixing/displacement ventilation register555in the manner of a displacement supply register. The resistance across the face of the baffle650is such as to cause resistance across the face of the baffle650thereby spreading the flow750broadly over the face area of the baffle650and out through the low restriction baffle700as indicated by the arrows710and therefore functions as displacement supply register venting air at a low velocity through relatively restrictive openings within the inner baffles650and the open baffle panel700.

FIG. 7Billustrates the sixth embodiment of the configurable mixing/displacement ventilation register555in mixing, or heating mode. As the heated air165enters the ventilation register plenum630it causes the thermal actuator10to act upon the push rod620to rotate the cap plate610on the pivot615to open the end of the plenum630. The heated air165thus predominately passes at a relatively high velocity out the lower, relatively small face area of an open outlet643of the configurable mixing/displacement ventilation register555so that it functions as a mixing supply register.

FIGS. 8A and 8Billustrate an alternative embodiment in which the return registers are changed over from heating to cooling mode, but the supply registers are in the same configuration in both heating and cooling mode. Displacement registers850are located in a room850. Displacement registers850are normal displacement registers installed in a system in which return air registers830and835exist. During cooling mode, the displacement registers850deliver cool air at floor level as illustrated and warm air stratified near the ceiling is returned via return registers830. As in previous embodiments, displacement supply air flow near the floor821and is heated by occupants810causing thermal plumes815which are indicated by isothermal lines805. Warm air870near the ceiling is drawn into the return air register and830. An air recirculating fan831, may optionally be provided to mix warm stratified air in the heating mode. The fan831may positioned at any point in a room including near the floor or in the middle. Note that where mixing is used, return registers at only one level may suffice, for example, only one set of return registers may be used such as those near the ceiling830or ones located at an intermediate height (not illustrated). The circulating fan831may be controlled locally using a sensor for detecting either cold temperatures near the floor, warm air near the ceiling, or a floor-ceiling differential temperature.

FIG. 8Billustrates the alternative embodiment of the conventional displacement ventilation register850in a heating mode. Heated air enters the room820at low velocity and rises. A return register located near the floor draws cooled air in. By arranging the return registers at a position remote from the displacement registers850, a circulation pattern can be established in the room that mitigates the undesirable stratification that can occur when using non-mixing type supply registers during heating.

FIGS. 9A and 9Billustrate an alternative embodiment in which the return registers are changed over from heating to cooling mode, and hydronic heating is used in place of force air heating. In the present embodiment, heating is done with a separate heating system under common control, for example hydronic heating using hydronic heaters980. Displacement registers950are normal displacement registers installed in a system in which return air registers930and935exist. During cooling mode, the displacement registers950deliver cool air at floor level as illustrated and warm air stratified near the ceiling is returned via return registers930. As in previous embodiments, displacement supply air flow near the floor and is heated by occupants915. Warm air970near the ceiling is drawn into the return air register and930.

FIG. 9Billustrates the alternative embodiment of the conventional displacement ventilation register850in a heating mode. Heated air enters the room from hydronic heaters. A return register935located near the floor draws cooled air in. By arranging the return registers at a position remote from the hydronic heaters980, a circulation pattern can be established in the room that mitigates the undesirable stratification that can occur when using non-mixing type supply registers during heating.

In many commercial buildings, heat may be lost through only one or two walls of an occupied space. For example, in an office building this is commonly the case. In a preferred embodiment of the generalFIG. 9Bembodiment, the rear wall in which at least one of the return registers935is located corresponds to that wall. This is so that the coldest air, which may be flowing downwardly along the surface of the “cold” wall, can be drawn into the one or more return registers935rather than mixing with the room air or causing the lower stratum of the room to get colder. The volume exchange rate may be sized to match the volume rate of the convective flow, which is readily predicted based on the outdoor air temperature, the conductivity and diffusivity of the wall, the film coefficients and so on according to known techniques. This is an excellent application for feed-forward or predictive model-based control because of the unsteady state of the wall system. In a preferred embodiment, such a model-based control scheme may take account of outdoor wind speed and direction, in addition to the obvious one of air temperature. In addition, such preferred embodiment may take account of conditioned space occupancy and predicted activity levels (for example, a lookup table based on time of day) so that activity-induced disturbances in the thermal convection field can be taken into account.

Obviously, a feed-forward scheme would not necessarily explicitly perform all such computations, for example, modeling the real-time temperature of the wall resulting from internal capacity and so on. But any control system controlling air exchanges based on the thermal flow from a cold wall would˜end to exchange more air when it is colder outside than when it is less cold. This makes the air changes independent of the load, which for a given outdoor temperature (and possibly other conditions, as discussed), may vary depending on the activity level, which can add additional heat generation to the system (e.g. office machinery, lights, etc.). In addition, many commercial building heating systems do not alter the air exchange rate in response to load, but instead alter the delivery temperature. So a system configured to withdraw the air near a cold wall at a sufficient rate to keep the cold wall-plume from mixing well with room air would provide a volume flow rate that is higher when the load is higher (outdoor air is colder). In addition, the rates would tend to be higher, at times, than the minimum air change criteria (for ventilation purposes) would require.

A simple way of providing the additional level of control for ameliorating the effect of cold wall convection is to place temperature sensors on the cold walls or at the level of the floor near the cold wall or walls.

In many cases, the cold wall is the outside wall and may be fitted with a window. This may make the placement of the return register in the middle of the wall difficult. However, one or more return registers935may be located at the ends of the cold wall on one or both adjacent perpendicular walls such that air is drawn from the same lower region of the cold wall.

The effect of providing substantial air changes in a space where non-mixing is provided is to push cold air near the floor out of the room so that warm air, which tends to stratify, can be pushed down toward the floor. If the flow rate is insufficient, the floor may remain cold (and therefore uncomfortable), continually replenished by a cold convective flow from the cold wall (or walls). Note that a beneficial side effect of this tradeoff of using displacement registers in heating mode is that the system, by avoiding mixing, may reduce the risk of injury due to contaminants in a space. In this case, consider that the general forced-convective flow is down toward the floor and out the return register. Referring toFIG. 10, in a central space conditioning system, one or more contaminant detectors1016may be located in a return air duct and the system shut down if dangerous contaminants are detected before such contaminants could be distributed in a building. Examples of detectable contaminants increase all the time due to enhancements in sensor technology, but examples include carbon monoxide, volatile organics, opacity, and particulate counts.

In many commercial buildings, heat may be lost through only one or two walls of an occupied space. For example, in an office building this is commonly the case. In a preferred embodiment of the generalFIG. 9Bembodiment, the rear wall in which at least one of the return registers935is located corresponds to that wall. This is so that the coldest air, which may be flowing downwardly along the surface of the “cold” wall, can be drawn into the one or more return registers935rather than mixing with the room air or causing the lower stratum of the room to get colder. The volume exchange rate may be sized to match the volume rate of the convective flow, which is readily predicted based on the outdoor air temperature, the conductivity and diffusivity of the wall, the film coefficients and so on according to known techniques. This is an excellent application for feedward or predictive model-based control because of the unsteady state of the wall system. In a preferred embodiment, such a model-based control scheme would take account of outdoor wind speed and direction, in addition to the obvious one of air temperature. In addition, such preferred embodiment may take account of conditioned space occupancy and predicted activity levels (for example, a lookup table based on time of day) so that activity-induced disturbances in the thermal convection field can be taken into account In many cases, the cold wall is the outside wall and may be fitted with a window. This may make the placement of the return register in the middle of the wall difficult. However, one or more return registers935may be located at the ends of the cold wall on one or both adjacent perpendicular walls such that air is drawn from the same lower region of the cold wall.

FIG. 10is an illustration of a central control system that may be used with various embodiments discussed herein. A programmable controller1000is connected to various sensors such as outdoor air temperature1010, indoor air temperature1015, supply air temperature1030, and return air temperature1035. The controller1000is also connected to a clock/calendar1020and various actuators for controlling the mechanical state of a space conditioning system including the actuators of the described multimode displacement registers, separate heating and cooling systems, and other mechanical elements described above.

FIG. 11shows a plan view of a room with multiple discharge registers1125,1135, and1145. The discharge pattern of each of the registers1125,1135, and1145, used individually, is shown at1100,1105, and1110, respectively. In an embodiment of the invention, to increase mixing with a given volume flow rate and eliminate dead spots, a single supply volume is differentially applied to a number of different registers1125,1135, and1145with the majority of the flow being output by a subset of all the different registers1125,1135, and1145at any given time. Thus, for a given flow volume, the discharge velocity at any given time will be higher than if the same flow volume were distributed more uniformly to all registers1125,1135, and1145. The above may be accomplished with any kind of register equipped with a flow-volume adjusting capability. The flow pattern may be shifted, for example, on a time-basis such that all flow is supplied to register1125for a period of a minute, then to register1135for a minute, and finally to register1145for a minute, then repeating and so on. The cycle of shifting can be varied to change faster or slower. Note that in the above embodiment, registers1125,1135, and1145may be configurable mixing/displacement ventilation registers according to any of the embodiments described herein. In one embodiment of the invention, flow may be cycled among the registers as described above, but only in the beating mode where a high velocity mixing effect is used whilst in a cooling mode, all registers are used since displacement ventilation is employed for cooling.

In an alternative embodiment, a single register1150has multiple outlets, each aimed in different directions as indicated by arrows1155. The flow is directed to each outlet in turn in a cycling pattern such that most of the supply flow is directed a single direction and then shifted to the next direction in turn. This creates varying flow patterns. The latter may be accomplished using a ventilation register device with an internal flow director such that only one inlet connection needs to be made to the supply ductwork.

Referring now toFIG. 14, a configurable mixing/displacement ventilation register1400has an internal plenum space1430defined by top,1484, rear1481, and side1482and1483panels and a tilted baffle plate1415toward a front1440. Air is supplied to the internal plenum space1430through an inlet collar1460that is attachable to an external duct system. A movable bottom plate1425is hinged at an edge1425A thereof. The bottom plate1425is shown in an intermediate position between a heating mode, in which the bottom plate1425drops down allowing air in the plenum space1430to exit through a slot1475and a cooling mode in which the bottom plate1425is in a raised position forcing all air through the tilted baffle panel1415. The slot is partly defined by a horizontal plate1420. The bottom plate1425may be actuated by, for example, by a mechanical actuator1465which may be a thermal motor, for example, or an actuator controlled by an external or internal control mechanism (not shown in the present drawing).

In the cooling mode, air flows into the plenum space1430and is forced through the tilted baffle panel1415and then through a front baffle panel1410. Little or no air escapes through the slot1475because, in the cooling mode, the bottom plate1425is in the up, or closed, position, thereby separating the plenum space1430from the slot1475. The angle of the tilted baffle panel1415makes the plenum-space1430progressively narrower toward the end of the plenum space1430that is remote from the inlet collar1460. This helps to make the flow through the tilted baffle panel1415uniform along its face. Air then exits the configurable mixing/displacement ventilation register1400through the front baffle panel1410bypassing through the gap1435. The size of the front baffle panel1410is relatively large and the average velocity through the front baffle panel1410is relatively low consistent with the function of a displacement-type register.

The configurable mixing/displacement ventilation register1400is preferably located adjacent or near a floor. In the heating mode, the bottom plate1425drops down allowing air to escape from the plenum space1430into the slot1475and out. Although some air will still escape the plenum space1430by flowing through the tilted baffle panel1415and then through the front baffle panel1410, much of it also escapes through the slot1475. The configuration overall may be designed such that the flow through the slot1475in the heating mode is relatively high, consistent with mixing-type ventilation.

This causes heated air to be projected (along the floor, in applications where the configurable mixing/displacement ventilation register1400is located adjacent or near the floor) well into the ventilated space. The velocity through the slot1475may be such that warm air from the front baffle panel1410is induced into the flow from the slot1475.

According to an optional feature of theFIG. 14embodiment, one or more flow deflector plates1455may be provided to deflect flow through the tilted baffle panel1415in the cooling mode. In the heating mode, the flow deflector plates1455may pivot down and against the tilted baffle panel1415.

In the heating mode the flow deflector plates1455may serve to partially (or completely) block the tilted baffle panel1415thereby forcing more air to pass through the slot. An arm may connect the flow deflector plates1455to the bottom plate1425so that the flow deflector plates1455are moved in unison with the bottom plate1425by the actuator1465.

Note that in various foregoing embodiments, the bottom portion, of the register remains fixed and flow is directed in a horizontal direction. By comparison, prior art multi-mode register devices, generally designed for commercial applications, direct air downwardly during a heating mode requiring the bottom to change configuration and may result in a change in overall height of the unit. According to inventive embodiments described herein, the bottom remains fixed and the space taken up by the register unit remains fixed. This is believed to be desirable in a floor-mounted register. Also, by directing high velocity flow adjacent the floor, a more persistent jet—a wall jet—may be generated as compared to a free jet which tends to lose momentum faster.