EP1762159A1 - Method and system for improving of the operation of refrigerated display cases - Google Patents

Abstract

The system, designed to prevent cold air from lingering between cold storage/display units along opposite sides of an aisle (E), consists of one duct (3) extending from the top (5) to the lower front edge of a unit (1) on one side of the aisle and a second duct (4) from the lower front edge (8) of an opposite unit (2) to its upper surface (7), drawn by an extractor fan (14). The ducts can be formed by the gaps between two units set back-to-back or between the back of one unit and an adjacent wall, with the air flow controlled by temperature sensors in the ducts.

Description

The invention relates to a thermal destratification process for increasing the temperature of an aisle lined unilaterally or bilaterally of refrigerated furniture and a system for carrying out this method. The invention applies more particularly to refrigerated aisles encountered in sales areas.

Commonly, in the sales areas, the temperature in aisles with refrigerated cabinets is low and lower than the temperature of the other areas of the sales area; this phenomenon is also called cold aisles. These differences in temperature cause discomfort for the customers and the conditions of purchases are not the most pleasant and comfortable possible. As a result, customer turnaround time in these areas is shortened, affecting the sale of goods in these areas.

In order to solve this problem, several solutions are known in the prior art.

One solution is to have blowing devices, in height in the sales area. These devices intended to homogenize the temperatures by destratification of the overall volume of air of the zone have fans blowing towards the space to be heated, the air taken in the upper part and therefore warmer. Note that depending on the devices, this air can still be heated by ancillary means such as a hot water heat exchanger or electrical resistors. However, this solution does not provide convincing results and / or significantly disrupts the operation of refrigerated furniture.

Another solution is to have radiant heating panels at low temperature, above the aisle to be heated or at ground level. However, this solution is expensive and requires significant work if it is not performed at the time of construction of the sales area.

It is also known in the prior art to integrate gutters into the building floor. These gutters have openings near the bottom of the furniture and the cold air of the sales area is drawn through these openings. However, this solution requires significant and expensive implementation work that is to be expected in the civil engineering of the building from its design and irreversibly lock the position of the refrigerated furniture sales.

Finally, it is also known refrigerated furniture having an air flow path between the upper part of the furniture and the lower part. These furniture are equipped with heating resistor (s) to heat the air that is sucked on the upper part. The sucked air is then expelled into the space between the furniture by the lower end of the air circulation path. However, this solution also consumes a lot of energy both in terms of the consumption of the electrical resistors and the refrigeration balance of the furniture. Indeed, the refrigeration balance of the furniture is increased because of the disruption of the air curtain which no longer forms an effective barrier with the atmosphere. It should be noted that the disruption of the air curtains can lead to the temperature failure of the goods stored in the refrigerating cabinet.

The invention therefore aims to remedy these problems by proposing a process for thermal delamination of aisles lined with refrigerated furniture which is efficient, energy efficient and does not disturb the operation of refrigerated furniture.

• former un premier chemin de circulation d'air s'étendant de la face supérieure du premier meuble à la face avant inférieure dudit premier meuble ;
• former un second chemin de circulation d'air s'étendant de la face supérieure du second meuble à la face avant inférieure dudit second meuble.

For this purpose, and according to a first aspect, the invention proposes a method of thermal regulation of an alley formed between a first and a second piece of furniture of which at least one of said pieces of furniture is refrigerated, said method providing for:

• forming a first air flow path extending from the upper face of the first piece of furniture to the lower front face of said first piece of furniture;
• forming a second air flow path extending from the upper face of the second piece of furniture to the lower front face of said second piece of furniture.

• d'aspirer de l'air depuis l'allée à travers le premier chemin ou expulser de l'air vers l'allée à travers le premier chemin ; et
• d'aspirer de l'air depuis l'allée à travers le second chemin.

The method simultaneously provides:

• suck air from the driveway through the first path or expel air to the driveway through the first path; and
• to suck air from the driveway through the second path.

When air is drawn through the first and second path, the cold air taken from the bottom is replaced by hot air from the upper strata.

When air is expelled to the driveway through the first path and air is drawn from the driveway through the second path, a fluidized bed is created in contact with the ground. Thus, the cold air is driven, as in the previous case and replaced by hot air present in the upper part.

Thus, no heating source is used because the process uses the calories present in the upper part of the sales area. Therefore, the energy consumption is low.

In addition, the air curtains of the furniture are undisturbed, the created air movements being parallel and having the same direction of circulation as those of the air curtains integrated in the refrigerating cabinets. Thus, the energy consumption of the refrigerating equipment is not increased and the temperature resistance of the products is ensured.

Finally, the implementation of this method is relatively fast and does not require significant work in the customer area.

According to a second aspect, the invention also proposes a thermal destratification system making it possible to implement said thermal de-stratification process.

• la figure 1 est un schéma de fonctionnement du système et du procédé de déstratification thermique selon l'invention, l'air étant expulsé vers l'allée à travers le premier chemin et aspiré depuis l'allée à travers le second chemin.
• la figure 2 est un schéma de fonctionnement du système et du procédé de déstratification thermique selon l'invention, l'air étant aspiré depuis l'allée à travers le premier et le second chemin.
• la figure 3 est un graphique représentant les variations de température et d'humidité en fonction de la hauteur.

Other objects and advantages of the invention will become apparent from the following description, made with reference to the appended drawings, in which:

• Figure 1 is an operating diagram of the thermal desalting system and method according to the invention, the air being expelled to the aisle through the first path and sucked from the aisle through the second path.
• Figure 2 is an operating diagram of the system and method of thermal destratification according to the invention, the air being sucked from the aisle through the first and the second path.
• Fig. 3 is a graph showing temperature and humidity variations as a function of height.

In sales areas with refrigerated cabinets 1, 2, 9, there is usually considerable stratification of the air. The hot air remains in the upper part of the sales area while the fresh air accumulates in the alley E formed between the refrigerated cabinets 1, 2. The customer thus experiences significant discomfort when passing through the room. aisle E. Figure 3 illustrates the variations of humidity and temperature as a function of height from the ground 11. It will be noted that in the aisle E formed between the refrigerating cabinets 1, 2, the temperature is close to 10 ° C at ground level and that in zone P close to the ceiling, the temperature is close to 30 ° C.

The method according to the present invention makes it possible to regulate the temperature of the aisle E formed between a first piece of furniture 1 and a second piece of furniture 2; at least one of the furniture 1, 2 being refrigerated.

Advantageously, the refrigeration of the refrigerating cabinets 1, 2, 9 is provided by a cooling system comprising fans for making a cold air circuit inside the cabinet and in particular a cold air curtain close to the cabinet. opening said furniture.

A first air flow path 3 extends from the rear of the upper face 5 of the first furniture 1 to the lower front face 6 of said first furniture 1 and a second air circulation path 4 extends from the rear of the upper face 7 of the second piece of furniture to the lower front face 8 of said second piece of furniture 2.

Advantageously, a third piece of furniture 9 and the first 1 or second piece of furniture 2 are arranged back-to-back. Thus, the space formed between the third 9 and the first 1 or second piece of furniture 2 respectively forms a first portion of the first 3 or second air circulation path 4. The second part of the air circulation paths 3, 4 is formed between the lower face 10 of the refrigerating cabinet 1, 2 and the floor 11.

Of course, a fourth piece of furniture can also be arranged back-to-back with the first 1 or second piece of furniture 2 refrigeration. Thus, the first portions of the first 3 and second air circulation path 4 are formed between two refrigerating units 1, 2, 9.

Note that the third and / or fourth furniture may be non-refrigerated display furniture. In this case, if the non-refrigerated display unit is perforated on its vertical face, arrangements can be added on its rear face to prevent air loss at the first 3 or second path 4.

In a particular embodiment, the first 1 or second refrigeration unit 2 is arranged against a wall 12. It is then possible to use the space between the wall 12 and said cabinet 1, 2 to form a first part of the first 3 or second path 4 air circulation. It will be noted that in this embodiment, the second part of the path 3, 4 is also formed between the lower face 10 of the refrigerating cabinet and the floor 11.

In order to regulate the temperature of the aisle E, the method simultaneously expels air towards the aisle through the first path 3 and suck air from the aisle E through the second path 4.

Thus, the cold air present in the aisle E is driven by the fluidized bed created parallel to the floor 11 of the aisle E, and then rejected above the second refrigerating cabinet 2 to lower the temperature strata of said aisle . In combination, hot air from the top of the first refrigerating cabinet 1 is expelled into the aisle E to replace the cold air sucked in by the warmer air.

Thus, the air curtains of the refrigerating cabinets 1, 2 are not disturbed because no turbulence conducive to these disturbances is created.

In another mode of application, the method also provides for simultaneously drawing air from the aisle E through the first 3 and second 4 paths. In this case, it will be necessary to regulate the air flows in the first 3 and second 4 paths in order to avoid excessive depression in the aisle which would disturb the air curtains.

The air circulating in the second path 4 may be sucked or expelled depending on the configuration of the furniture to be equipped and the environment thereof. For example, in the case where refrigerated furniture 2 would be juxtaposed to a piece of furniture "fruit and vegetables", it will be necessary to ensure suction at this level because blowing hot air would cause drying of fruits and vegetables.

Note that if the products in the furniture are not fragile, one can choose to suck or expel air through the second path 4.

The system for implementing the thermal destratification process comprises suction means 14, 15 and expulsion 13 of the air. In the embodiment of the invention illustrated in Figures 1 and 2, the suction means 14, 15 and expulsion 13 of the air are fans associated with the upper face 5, 7 of the furniture 1, 2 .

Advantageously, the speed of the fans and therefore the flow rates of air through the first 3 and second 4 air circulation paths can be regulated according to a set temperature and at least one temperature sensor placed in the first 3 and / or second air circulation path 4.

In one embodiment of the invention, the thermal destratification system further comprises at least one sheath 16, 17. In FIG. 1, a first sheath 16 is disposed on the upper face 5 of the first piece of furniture 1 in the continuity of the first path 3 and a second sleeve 17 is disposed on the upper face 7 of the second piece of furniture 2 in the continuity of the second path 4.

When the sheath 17 is connected to a suction means 14 of the air of the aisle E, the latter makes it possible to distribute the air to an area of the sales area to be cooled or to reject it to the outside of the sales area. When the sheath 16 is connected to a means 13 for expelling air to the aisle E, it expels warmer air from a higher stratum.

Advantageously, perforated skirting boards 18 are arranged at the end of the air circulation paths 3, 4 on the lower front face 6, 8 of the furniture 1, 2 in order to allow air circulation.

Six functional tests of the thermal control process were carried out and six temperature probes were placed in the aisle E, at different heights.

• Sonde 1 : 0 m du sol ;
• Sonde 2 : 0,5 m du sol ;
• Sonde 3 : 1 m du sol ;
• Sonde 4 : 1,5 m du sol ;
• Sonde 5 : 2 m du sol ; et
• Sonde 6 : 2,5 m du sol.

The measurement heights of the probes are as follows:

• Probe 1: 0 m from the ground;
• Probe 2: 0.5 m from the ground;
• Probe 3: 1 m from the ground;
• Probe 4: 1.5 m from the ground;
• Probe 5: 2 m from the ground; and
• Probe 6: 2.5 m from the ground.

Test N ° 1 was carried out without any ventilation.

• 6 pour l'essai N°2 ;
• 4 pour l'essai N°3 ;
• 2 pour l'essai N°4 ; et
• 1 pour l'essai N°5.

Tests Nos. 2 to 5 were carried out with the same speed for suction fans and blower fans. The operating speeds of the fans are as follows:

• 6 for test No. 2;
• 4 for test No. 3;
• 2 for test No. 4; and
• 1 for test No. 5.

Note that the speed of operation of the fans is noted 1 for a fast speed and 6 for a slow speed.

Finally, the test N ° 6 was carried out with a speed 4 for the blowers and a speed 1 for the sucking fans.

The following table shows the temperatures measured by the different probes according to the operating mode of the fans: Probe 1 Probe 2 Probe 3 Probe 4 Probe 5 Probe 6 T (° C) T (° C) T (° C) T (° C) T (° C) T (° C) Trial 1 9.03 9.19 9.48 16,70 22,08 22.56 Trial 2 12.06 12.15 11,67 14.17 22.65 23.06 Trial 3 15.70 14.76 14.35 18.92 21.98 22,14 Trial 4 16.76 14.72 14.32 18.87 21.98 22,15 Trial 5 15,06 13,30 13.41 18.25 22,20 22.46 Trial 6 14.51 13,31 13,28 18,10 22.21 23.39

Note that the air movement created by this invention also has another interest that is to avoid the accumulation of condensation behind and under the furniture 1, 2, 9, which helps keep them in good condition.

Note that an additional heating system can be put in place at the fans to increase the temperature of the air coming from the top of the furniture and expelled into the aisle E. This may be necessary if the temperature is insufficient at the top of the furniture where the air is taken up. The heating of the air can be ensured by the addition of electric resistances or a hot water coil supplied by any source (water heating, heat recovery ...)

Claims (10)

A process for the thermal de-stratification of an aisle E formed between a first (1) and a second furniture (2) of which at least one of said furniture (1, 2) is refrigerated, said method providing for: forming a first air circulation path (3) extending from the upper face (5) of the first piece of furniture (1) to the lower front face (6) of said first piece of furniture (1); forming a second air circulation path (4) extending from the upper face (7) of the second piece of furniture (2) to the lower front face (8) of said second piece of furniture (2), said method being characterized in that it simultaneously provides: sucking air from the aisle E through the first path (3) or expelling air towards the aisle E through the first path (3); and - To suck air from the aisle E through the second path (4). Thermal delamination process according to claim 1, characterized in that it provides for the provision of a third piece of furniture (9) and the first (1) or second piece of furniture (2) back-to-back, the space between the third (9) ) and the first (1) or second piece of furniture (2) respectively forming a first part of the first (3) or second air circulation path (4), a second part of said path (3, 4) being formed between the face lower (10) of said first (1) or second piece of furniture (2) and the ground (11). Thermal delamination method according to one of claims 1 or 2, characterized in that it provides for placing the first (1) or second piece of furniture (2) against a wall (12), the space formed between the wall (12) ) and said furniture (1, 2) respectively forming a first portion of the first (3) or second air circulation path (4), a second portion of said path (3, 4) being formed between the lower face (10) said furniture (1, 2) and the floor (11). A method of thermal destratification according to one of claims 1 to 3, characterized in that it provides for regulating the flow rates of air through the first (3) and second (4) air flow paths as a function of a temperature setpoint and at least one temperature sensor placed in the first (3) and / or second path (4) of air circulation. Thermal destratification system for implementing a thermal regulation method, according to one of claims 1 to 3, of an aisle E formed between a first (1) and a second piece of furniture (2) including at least one of said furniture (1, 2) is refrigerated, said system comprising: a first air circulation path (3) extending from the upper face (5) of the first piece of furniture (1) to the lower front face (6) of said first piece of furniture (1); a second air circulation path (4) extending from the upper face (7) of the second piece of furniture (2) to the lower front face (8) of said second piece of furniture (2), said system being characterized in that it further comprises: an air suction means (15) from the aisle E through the first path (3) or an expulsion means (13) from the air towards the aisle E through the first path ( 3); and - A suction means (14) of the air from the aisle E through the second path (4). Thermal destratification system according to claim 5, characterized in that the means for suction (14, 15) and expulsion (13) of the air are fans associated with the upper face (5, 7) of said furniture ( 1, 2). Thermal destratification system according to one of claims 5 or 6, characterized in that it further comprises at least one sheath (16, 17) disposed on the upper face (5, 7) of the first (1) or second piece of furniture (2), respectively in the continuity of the first (3) or second path (4), said sheath (16, 17) for distributing the air sucked into the aisle E to an area to be cooled, or to collect warmer air from a higher height. Thermal destratification system according to one of Claims 5 to 7, characterized in that it comprises heating systems at the level of fans expelling air to aisle E to increase the temperature of exhaust air. Thermal destratification system according to one of claims 5 to 8, characterized in that it further comprises at least one temperature sensor disposed in the first (3) or second path (4) of air circulation. Thermal air delaminating system according to one of Claims 5 to 9, characterized in that it comprises perforated skirting boards (18) arranged at the end of the air circulation paths (3, 4) on the face lower front (6, 8) of the furniture (1, 2).

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