KR20010100320A - Heat accumulating bricks for hot blast heater - Google Patents

Abstract

A heat storage brick for an electric heat blower, and a plurality of heat storage bricks are stacked as an assembly, the heat storage brick is provided with a heating wire receiving groove on at least one surface to accommodate the heating wire connected to the electrical device using the late-night electricity, It penetrates in the thickness direction to constantly discharge the heat accumulated by the heating wire to the outside, thereby providing the inlet and outlet holes so that air is drawn in and discharged so that heat exchange can occur.

Therefore, by minimizing the air layer that hinders the heat transfer, the heat storage performance is improved, and the structure of the air flowing in and out of the air is provided to increase the heat exchange and the effective heat dissipation efficiency, thereby saving energy. It is possible to reduce the heating cost of the room, it is effective to increase the reliability of the electric heater.

Description

Heat accumulating bricks for hot blast heater}

The present invention relates to a heat storage brick for an electric heat blower, and more particularly, to an electric heat blower for heating by using a late-night electricity, to improve the heat storage performance of the heat storage brick used in the electric heat blower and increase the emission efficiency energy Efficient use as well as to maintain a constant temperature during heating relates to a heat storage brick for an electric warmer that can maintain a comfortable room temperature.

In general, electric heaters use low-cost late night electricity to heat up bricks at night (22: 00-08: 00) and heat them with a blower during daytime (08: 00-22: 00) to heat them. A clean heating device comprising a case forming an exterior, a blower, a brick assembly capable of heat storage inside the case, an electrical device capable of supplying heat to the brick assembly, and a heating wire connected to the electrical device. . In particular, the brick assembly, as shown in FIG. 7, stacks a plurality of bricks 101, 103, 105, 107, 109, 111,..., Between the brick 101 and the brick 103. It provides a structure in which hot wires (not shown) can be arranged. As shown in FIGS. 7 and 8, the conventional heat storage brick induces air flow to the outer surface to heat the cold air to radiate heat through the blower 101a, 101b, 101c, and 101d. , 103a, 103b, ..., 111a, 111b, ...) are provided.

The electric warmer formed as above heats a plurality of bricks (101, 103, 105, 107, 109, 111, ...) using the late night power drawn through the electric device, and operates the blower during the daytime Will be done. At this time, when the blower is operated, cold air outside the case is introduced into the bottom side of the block 111, and moves along the air guide grooves 111a, 111b, ... to heat up with the heated brick, thereby inducing air on the opposite side. Continued to move along the grooves (101c, 101d, ...) is discharged into the room through the air outlet provided in the case is heated.

However, the heat storage brick used in the conventional electric warmer has a wide air layer for reducing the heat transfer efficiency between the blocks and the heat storage performance is reduced, the heat exchange efficiency is not good because the air flow is not smooth during the heat exchange process. Low energy efficiency is low, the temperature of the room is not kept constant during the heating time has a problem that can not maximize the performance as a heater. In addition, the effective heat dissipation efficiency is increased according to the flow rate of the air and the heat exchange efficiency, there is a problem that the effective heat dissipation efficiency is low enough to perform indoor heating.

Therefore, the present invention has been proposed to solve the above problems, an object of the present invention is to minimize the air layer that interferes with the heat conduction to improve the heat storage performance, to increase the heat exchange efficiency by configuring the flow path to smooth air flow Of course, the present invention provides a heat storage brick for an electric hot air heater, which improves effective heat dissipation efficiency, making it suitable for indoor heating, and increasing energy efficiency to reduce the cost required for indoor heating.

In order to achieve the above object, the present invention is a plurality of stacked up, down and left and right to form an assembly, and is arranged in the electric warmer to heat the heat generated by electricity and radiate heat for a predetermined time to heat the room In the heat storage brick, the heat storage brick is provided with a plurality of hot wire receiving grooves are provided so that the heating wire is connected to the electrical device to generate heat by electricity repeatedly arranged in the longitudinal direction, located between the hot wire receiving grooves, the thickness The plurality of inlet hole parts through which heat is exchanged while the outside air is introduced from the lower side to the upper side, and the air passing through the inlet hole is drawn in from the upper side to the lower side to perform heat exchange again, and at a predetermined interval from the inlet hole. Is spaced between the hot wire receiving groove and penetrated in the thickness direction Of the heat storage brick provides for an electric fan heater including a vent hole.

In the heat storage brick for electric hot air heater thus formed, heat is accumulated in the heat storage brick by a heating wire connected with an electric device using late-night electricity. And when dissipating the heat accumulated, heat is exchanged as the air introduced by the blower enters from the lower side to the upper side of the inlet hole, and the heat passing through the inlet hole continues to pass from the upper side to the lower side of the outlet hole again. This is made and discharged below the discharge hole.

1 is a schematic configuration diagram of an electric warmer for explaining an embodiment according to the present invention;

Figure 2 is a perspective view showing the form of assembling each other bricks used in the electric warmer according to the present invention,

3 is a perspective view showing part A of FIG. 2 in detail;

4 is a perspective view showing part B of FIG. 2 in detail;

5 is a view showing a flow of air according to an embodiment of the present invention,

6 is a graph for comparing the efficiency of the present invention and the conventional heat storage brick,

7 is a perspective view illustrating an air flow of a conventional heat storage brick;

FIG. 8 is a view showing any of the bricks shown in FIG. 7.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic perspective view showing an electric heater for explaining an embodiment according to the present invention, a case 1 forming an appearance and a heat storage brick assembly 3 disposed inside the case 1; It is shown. The case 1 is provided with a discharge part 5 for discharging hot air for heating on the bottom face of the front side, and an air inlet (not shown) is provided on the bottom face of the rear side to allow external cold air to be introduced therein. The case 1 is provided with an electric device (not shown) for heating and accumulating the block assembly 3 by using a late night electricity therein. The electric device includes a conventional earth leakage breaker or the like. And the case (1) is provided with a blower (7) to facilitate the intake and discharge of air for heating therein.

2 is a perspective view showing the heat storage brick assembly 3 according to the present invention, showing a state in which a plurality of heat storage bricks 11, 13, and 15 are stacked. As shown in FIG. 3, the heat storage brick 11 is provided with a plurality of hot wire accommodating grooves 11a, 11b, 11c, and 11d in which hot wires are accommodated. The hot wire receiving grooves 11a, 11b, 11c, and 11d have a semicircular cross section.

The heat storage brick 11 has discharge hole portions 11e and 11f and lead holes 11g penetrating in the thickness direction between the heating wire accommodating grooves 11a and 11b and the other heating wire accommodating grooves 11c and 11d. 11h) is provided. The inlet holes 11g and 11h allow air to flow so that heat is exchanged in the heat storage brick 11 where the outside air is drawn from the lower side to the upper side, and the discharge holes 11e and 11f are the heat exchanger. This made air is drawn from the upper side to the lower side is to be discharged to heat the room again while the heat exchange occurs again.

FIG. 4 is a perspective view showing one of the other heat storage bricks 13 arranged on both sides of the heat storage bricks 11 and showing its structure, and the inlet hole portions 13a, 13b, 13c, and 13d penetrating through the thickness thereof. Are arranged at equal intervals, and the discharge holes 13e, 13f, 13g, and 13h are shown at a constant distance. The number of the inlet holes 13a, 13b, 13c, and 13d and the outlet holes 13e, 13f, 13g, and 13h may vary depending on the length of the heat storage brick 13. And the heating wire receiving grooves (13i, 13j) has a structure in which the end is connected in a round shape so that the heating wire can be extended to form.

On the other hand, the heat storage bricks (11, 13, 15) is preferably made of a magnesia-based material in order to increase the reverse performance.

The heat storage bricks 11, 13, and 15 are stacked in the shape of FIG. 2 as described above by stacking them up, down, left, and right so as to correspond to the above-described inlet and outlet holes, respectively. Will be assembled. The heat storage brick assembly thus assembled is disposed inside the case 1 so that the heating wire is connected to an electric device for using a late night electricity. At this time, the case 1 is the inlet hole (11g, 11h, 13a, 13b, ...) and the discharge hole (11e, 11f, 13e, 13d, ...) on the side where the heat storage brick assembly is disposed A partition 10 or the like that can be divided is provided.

Therefore, when the hot wire is heated using electricity in the late night time zone, the hot wire provided in the hot wire accommodating grooves 11a, 11b, 11c, 11d, 13i, and 13j is heated and stored in the brick.

Then, when the blower 7 is driven during the daytime, the external cold air moves from the lower side of the inlet hole 11g, 11h, 13a, 13b, ... to the top to perform heat exchange, and again the exhaust hole 11e. , 11f, 13e, 13d, ...) is drawn upwards and the heat exchanged air is moved downwards while the heat is exchanged again. Therefore, the air heated by the heat exchange is discharged to the discharge part 5 of the case 1 to perform indoor heating.

The data compared with the conventional will be described in detail according to the experimental values relating to the heat storage performance and the heat radiation efficiency of the heat storage brick according to the present invention and the heat storage brick according to the present invention.

First, experimental data related to heat storage performance of heat storage bricks will be described in comparison with the prior art.

In the heat storage brick of the present invention, the total loss volume (Vd) due to the width (a, 18.0 cm), length (b, 20.0 cm), height (c, 65 cm), and the diameter of the inlet and outlet holes (d) is 77.3. Assuming that cm 3, the corresponding heat storage brick is the sum of the lost volumes considering the width (a ', 18.0cm), length (b', 20cm), height (c ', 70cm), and space through which air passes. The comparison will be described assuming (Vd ') as 674.6 cm 3.

Heat storage brick of the present invention)

Calculation of cross section (A)

Total cross section (At) = width (18.0) X length (20.0) = 360 ㎠

Loss Cross Section (Al) = ?? (1.5) 2/4 X 4 = 7.1 cm²

Effective heat storage area (A) = At-Al = 360-7.1 = 352.9 cm²

Porosity = Al / At = 7.1 / 360 = 0.02

Volume (V) calculation

Total Volume (Vt) = Horizontal (18.0) X Vertical (20.0) X Height (6.5) = 2340 cm³

Lost Volume (Vl1) = (π (1.0) ² / (4 X 2) X 20) X 4 = 31.4 cm³

Lost Volume (Vl2) = (π (1.5) ² / 4) X 6.5 X 4 = 45.9 cm³

Effective volume (V) = Vt-Vl1-Vl2 = 2340-31.4-45.9 = 2262.7 cm³

Conventional heat storage brick)

Calculation of cross section (A)

Corrected total area (At) = width (18.0) X length (20.0) = 360 cm²

Loss area (Al) = (4.5 X 1.5) X 4 = 27 cm²

Compensation effective heat storage area (A) = At-Al = 360-27 = 333 cm²

Porosity = Al / At = 27/360 = 0.075

Volume calculation

Total correction (Vt) = 18.0 X 20.0 X 7 = 2,520 cm³

Total Loss Volume (Vl) = (4.5 X 1.5) X 7 X 4 = 674.6 cm 3

Corrected effective volume (V) = Vt-Vl = 1,955.4 cm³

On the other hand, it can calculate by heat storage quantity Q = M Cp (T2-T1).

here,

Q: Calorie (Kcal)

M: Weight (Kg)

Cp: Specific Heat (Kcal / kg ℃) = 0.263 (Magnesia Brick)

T2: Heating temperature (700 ℃)

T1: Room temperature (20 ℃)

M = V (effective volume, cm³) X Sg (density, g / cm³)

Sg = 3.315 g / cm³.

Therefore, the heat storage amount per heat storage brick of the present invention is

Q = (2,263 X 3.315 / 1,000) X 0.263 X (700-20)

= 1,341.6 Kcal (≒ 116%).

And the amount of heat storage per conventional heat storage brick is

Q = (1,955.4 X 3.315 / 1,000) X 0.263 X (700-20)

= 1,159.3 Kcal

The data shown in Table 1 can be obtained by the calculation result.

Item unit Conventional heat storage brick Regenerative brick of the present invention Porosity % 7.5 2 Heat storage volume Cm 3 1,955.4 2,262.7 Heat storage per brick ㎉ 1,159.3 1,341.6

Therefore, it can be seen that the porosity is small in the heat storage brick of the present invention. This improves the heat transfer effect by reducing the residence space of the air, which lowers the heat storage efficiency, and thus the heat storage is performed quickly.

In addition, the heat storage volume can be seen that the heat storage brick of the present invention is large, so that the air flow path is located inside the brick to maximize the heat storage volume can be seen that the amount of heat storage is greatly increased under the same or similar conditions.

Even if the heat storage brick is well thermally stored, if the heat generation performance is poor, not only the heat retention can be properly exchanged, but also insufficient heating of the room and waste of energy. Therefore, it is necessary to maximize the heat dissipation efficiency by increasing the flow rate of air in order to effectively heat exchange in the warm air.

Subsequently, experimental data related to the heat dissipation efficiency of the heat storage brick will be described in comparison with the prior art.

Average velocity V = Q / Al in heat storage brick flow path

here,

V: mean flow rate (m / sec)

Q: Blowing air volume (1.4 m³ / min / 60/4 = 0.0058 m³ / sec)

Al: Euro area (m²)

Here, the heat storage brick flow rate of the present invention is calculated as follows.

V = Q / Al = 0.0058 / (π (0.015) ² / 4 X 4) = 8.21 m / sec

Here, the conventional heat storage brick flow rate is calculated as follows.

V = Q / Al = 0.0058 / (0.0027) = 2.15 m / sec

Item unit Conventional heat storage brick Regenerative brick of the present invention Average flow rate m / sec 2.15 8.21

As can be seen from the above results, the high flow rate is efficient for minimizing the stagnant portion of air in the hot air heater and for uniform heat transfer, and the heat storage brick of the present invention satisfies these conditions.

The following is a comparison of the air volume fraction of heat storage bricks.

Heat storage brick of the present invention)

Vb (regenerative volume) = Vt (total volume) X 6 + 3,600 cm³ (upper air layer)

= 2,340 X 6 + 3,600 = 17,640 cm³

Va (air volume) = 3,600 + Vln X 6 (loss volume)

= 3,600 + (31.4 + 45.9) X 6

= 4,063.8 cm³

Ve (effective heat storage volume) = Vb-Va = 17,640-4,063.8 = 13,576.2 cm³

Air volume fraction = Va / Vb = 4,063.8 / 17,640 = 23.1%

Conventional heat storage brick)

Vb (regenerative volume) = Vt (total volume) X 6 + 3,600 cm³ (upper air layer)

= 2,520 X 6 + 3,600 = 18,720 cm³

Va (air volume) = 3,600 + Vln X 6 (loss volume)

= 3,600 + (189 + 13.8 + 110 + 220 + 31.8) X 6

= 6,987.6 cm³

Ve (effective heat storage volume) = Vb-Va = 18,720-6,987.6 = 11,732.4 cm³

Air volume fraction = Va / Vb = 6,987.6 / 18,720 = 37.3%

Item unit Conventional heat storage brick Regenerative brick of the present invention Air volume ratio % 37.3 23.1

As can be seen from the above results, the air not only impedes the heat storage, but also stagnates in the room unnecessarily even during heat dissipation, which prevents even heat dissipation. Compared with the improvement can be seen.

And comparing the residual heat and effective release rate of the brick is as follows.

Heat storage brick of the present invention)

Residual heat

Qr = heat storage (Q)-heat dissipation (Qs)

here,

Qs = M Cp (T2-T1) = 7.5 X 0.263 X (700-72)

= 1,238.7 Kcal

Q = 1,341.6 Kcal (calculated in Attachment 2)

Therefore, residual calorie Qr = 1,341.6-1.238.7 = 102.9 Kcal

Calorie effective release rate = Qs / Q = 1,238.7 / 1,341.6 = 92.3%

Conventional heat storage brick)

Residual heat

Qr = heat storage (Q)-heat dissipation (Qs)

here,

Qs = M Cp (T2-T1) = 6.0 X 0.263 X (700-260)

694.3 Kcal

Q = 1,159.3 Kcal (calculated in Attachment 2)

Therefore, residual calorie Qr = 1,159.3-694.3 = 465 Kcal

Calorie Effective Release Rate = Qs / Q = 694.3 / 1,159.3 = 59.9%

Item unit Conventional heat storage brick Regenerative brick of the present invention Temperature of buckwheat after 14 hours heat radiation ℃ 260 72 Room temperature after 14 hours ℃ 15 20 Residual heat after 14 hours ㎉ 465 102.9 Effective release rate % 59.9 92.3

As can be seen from the above results, it can be seen that the heat dissipation efficiency is remarkably improved as compared with the conventional heat storage brick, and the effective emission rate is increased. Therefore, the design of the air flow path inside the brick not only increases the heat exchange efficiency by eliminating the stagnant portion in the heat storage material, but also continuously releases the heat amount of the heat storage material, thereby increasing the effective emission efficiency.

The comparative data by such an experiment is shown in FIG. It can be seen from the data shown in FIG. 6 that the temperature of the heat storage brick releases sufficient heat with time, and thus the temperature of the room is kept constant.

As described above, the present invention includes a plurality of heat storage bricks stacked in an assembly. The heat storage brick has a heat wire receiving groove capable of storing a heat wire connected to an electric device using a late night electricity on at least one surface thereof, and heat storage by the heat wire It is penetrated in the thickness direction to constantly discharge the heat to the outside, so that the air is introduced and discharged to provide the inlet and outlet holes so that heat exchange can occur. Therefore, by minimizing the air layer that hinders the heat transfer, the heat storage performance is improved, and the structure of the air flowing in and out of the air is provided to increase the heat exchange and the effective heat dissipation efficiency, thereby saving energy. It is possible to reduce the heating cost of the room, it is effective to increase the reliability of the electric heater.

Claims (5)

In the heat storage bricks are arranged in an electric hot air heater in order to heat the indoor heat by accumulating the heat generated by the electricity and heat for a predetermined time by forming a plurality of stacked up, down and left and right, the assembly, The heat storage brick includes a plurality of hot wire receiving grooves which are connected to an electric device so that the hot wire which generates heat by electricity is repeatedly arranged in the longitudinal direction; A plurality of inlet holes positioned between the hot wire accommodating grooves and penetrating in the thickness direction and exchanging external air from the lower side to the upper side to perform heat exchange; A plurality of discharge holes that are exchanged with the air passing through the inlet hole from the upper side to the lower side, and are spaced apart from the inlet hole so as to be spaced apart from each other and positioned between the heating wire receiving grooves; Regenerative brick for electric hot air fan comprising a. The heat storage brick of claim 1, wherein the inlet hole and the outlet hole are disposed at equal intervals in the longitudinal direction. The heat storage brick of claim 1, wherein the heat storage brick is made of magnesia. The heat accumulator brick of claim 1, wherein the heat ray receiving groove has a semicircular shape in cross section. The heat storage brick of claim 1, wherein the heating wire receiving groove is formed on one surface of the heat storage brick.