SK281794B6 - Device for flowless measuring of the thermal amount - Google Patents

Abstract

The solution relates to measuring the amount of heat delivered or received by the heater. No flowmeter is used in the measurement. Measured values are given directly in physical units. The main problem of similar flowless methods, which is the low reproducibility of the measurement of representative radiator and ambient reference temperatures, is solved by using one or more calorimetric sensors. The heat accumulation block (9) and the heat exchange block (10) are connected by a constant heat resistance (11). Both the heat storage block and the heat exchange block are equipped with temperature meters (12) and (13). The constant thermal resistance (11) is isolated from the environment by a thermal insulation layer (14). The heat accumulation blocks are in a defined heat conducting contact connected to the selected heating element locations, e.g. heating medium supply and outlet. The heat exchange blocks (10) are cooled by ambient air. The temperature gradients measured in the calorimetric sensors are in a reproducible relationship with the amount of heat delivered by the heating element to the environment. The measured data are processed in a microcomputer unit and evaluated in physical units (kWh or MJ) for the selected time period.

Description

Technical field

The invention relates to the measurement of the amount of heat transferred or received by a heating or cooling body which extracts heat or cold from the medium flowing therethrough. The measurement does not require a flow meter and the measured values are directly expressed in physical units.

BACKGROUND OF THE INVENTION

In particular, flow measurement devices are used to measure the amount of heat transferred to the surroundings by the radiators that extract heat from the medium flowing through them, which evaluate the heat flow based on the flow rate of the respective medium and the difference in medium temperatures at the inlet and outlet of the radiator. The disadvantage of these flow-through devices is that they are technically demanding, relatively expensive, and require special control, because over time the flow-meters become clogged with impurities from the flowing medium and thus change their main characteristics. In addition, they have a considerably limited use from a practical point of view.

Measurements of low flow rates below 10 l / h, which are common in conventional radiators in flats, for example, are subject to a large error. Otherwise, at a high flow rate, the temperature difference of the medium at the inlet and outlet of the heater may be low, and then the measurement of the temperature difference is burdened with a larger error. Another drawback of these flow-through devices is the necessity of mounting the flow-meter in the heating system hydraulic system. Even the solution according to the Czechoslovak invention protected by AO 239511 did not avoid similar problems, although the flow rate is measured in an unconventional way. In addition to such flow-through devices, non-flow-through devices are used which measure the amount of heat transferred based on various combinations of measurement of the inlet and outlet temperature of the medium, the surface temperature of the radiator and the ambient temperature. The disadvantage of these devices is low reproducibility of the measured values. This is due to the problems of measuring the representative surface temperature of the heater and also the problem of measuring the ambient temperature, which varies with the height from the floor and other factors, e.g. flow direction during air infiltration and ventilation, depending on the specific geometry of the heated room, etc. The solution according to the Czechoslovak invention AO 252 735 would, for example, measure a reduced heat consumption in winter with a fully opened window in a room despite a fully opened radiator valve compared to a room with a closed window and a partially closed radiator valve. For these reasons and nevertheless, these devices are used only as ratio measures. Heat costs are then recalculated on the basis of the total amount of heat delivered to the entire building (building) and the sum of the values measured by all ratio meters. By not measuring these meters in physical units, the consumer is unable to clearly evaluate their consumption on an ongoing basis and thus largely loses the incentive to save. The low plausibility of such costs often leads to a dispute between individual customers / residents.

SUMMARY OF THE INVENTION

The aforementioned drawbacks are eliminated by a device for flow-free measurement of the amount of heat transferred by the heating element, which consists in that at least one calorimetric sensor electrically connected to the evaluation microcomputer unit is placed on the heating element and / or on the heating medium supply. . It is preferred that two calorimetric sensors are used to measure the amount of heat transferred.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS The invention is explained in more detail below with reference to the drawing in which: FIG. 1 shows an example of placing calorimetric sensors on a heating element with a thermostatic control valve, FIG. 2 shows the overall arrangement of the calorimetric sensors and the evaluation unit, FIG. 3 shows a longitudinal section through a calorimetric sensor.

DETAILED DESCRIPTION OF THE INVENTION

The device for flow measurement of the amount of heat is generally shown on a heating element with a thermostatic control valve shown in FIG. The heater 1 has a heating medium inlet 2 equipped with a thermostatic control valve 3 and a heating medium outlet 4. Calorimetric sensors 5 and 6, which are the subject of the invention, are fastened to the heating medium inlet 2 and the heating medium outlet 4.

The sensors have the same or different ratios of length, cross-section, thermal conductivity of the heat storage block 9, the heat exchange block 10 and the constant thermal resistance 11.

In FIG. no. 2 shows the electrical connection of two calorimetric sensors 5 and 6 to an evaluation microcomputer unit 7, which shows the data on the display 8.

Fig. 3 shows in longitudinal section the construction of the calorimetric sensor 5 or 6. In the upper part there is a heat accumulation block 9, which is shown in FIG. 1 in the heat-conducting contact with the heating medium inlet 2 and in the second calorimetric sensor 6 it is in the heat-conducting contact with the heating medium outlet 4. Further FIG. 3 shows the heat exchange block 10, which is in a defined heat-conducting connection with the heat accumulation block 9 by means of a constant thermal resistance 11. The heat accumulation block 9 is equipped with a temperature meter 12 and the heat exchange block 10 is a temperature meter 13.

Industrial usability

The invention is useful in measuring the amount of heat transferred to the surroundings by individual heaters and also in conditions of several risers with heating medium in one housing unit. By measuring heat directly in physical units, it creates room for motivation to save heat.

Claims (4)

A heat-flow measuring device with surface temperature sensors of some parts of a heating element, characterized in that at least one heating element and / or a heating medium inlet (2) and / or a heating medium outlet (4) is provided on the heating element and / or a calorimetric sensor (5, 6) electrically connected to the evaluation microcomputer unit (7). Device according to claim 1, characterized in that two calorimetric sensors (5, 6) are arranged on the heating medium inlet (2) and on the heating medium outlet (4). Device according to claim 1 and 2, characterized in that the calorimetric sensor (5, 6) consists of a heat storage block (9) with a temperature meter (12), a heat exchange block (10) with a temperature meter (13) and a constant thermal resistance. (11). Apparatus according to claim 3, characterized in that all or part of the longitudinal surface of the surface of the calorimetric sensor (5, 6) is covered with a thermal insulation layer (14).