SU1689829A1 - Device for determination of heat of combustion of liquid and gaseous fuels - Google Patents

Abstract

The invention relates to the field of thermal and physical measurements, in particular, to devices for determining the heat of combustion of liquid and gaseous fuels. The purpose of the invention is to increase the expressiveness of the determination by eliminating the mutual influence of the measuring and comparative cells. The device comprises a fuel preparation and supply unit with an oxidizer, a rigid closed frame, inside which a measuring cell with a burner unit is installed and a comparative cell with an electric heater, an upper gauge unit, a lower unit and a lower isothermal unit in contact with the cells through thermal bridges. Heat flow meters are installed without a gap between the upper isothermal block and the upper end surfaces of the measuring and comparative cells. Heat flow meters are connected to the input of the automatic heat flow control system, the output of which is connected to the electric heater in the comparative cell, to the heater of the upper isothermal block and to the semiconductor thermopile cooling both isothermal units. Each cell is placed in a heat insulating casing. 1 il.

Description

The invention relates to the field of thermophysical measurements of the properties of substances.

The aim of the invention is to increase the express determination.

The drawing shows a diagram of the proposed device.

The device for determining the heat of combustion of liquid and gaseous fuels contains an adiabatic shell made in the form of a rigid frame 1 with air cooling fins, which is connected to the heat release junction semiconductor thermopiles 2 and 3, the heat absorbing junctions of which are in good thermal contact with the upper 4 and the lower 5 isothermal blocks; Thermal bridges 6 and 7, respectively, of the measuring 8 and comparative 9 cells of the calorimeter are soldered to the massive isothermal block 5, which through gauges 10 and 11 heat flux associated with the upper low-inertia isothermal unit 4, In the body of the isothermal unit 4 is installed an electric heater 12, meters

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the heat flux is connected to the inlet of the system 13 for automatic control of the heat flux (AARTP). The output of CAPD 13 is connected to the heater 12 of the isothermal unit 4 and the electric heater 14 located in the comparative cell, as well as to the semiconductor thermoelectric cells 2 and 3. In the measuring cell there is a burner 15. Each cell is enclosed in heat-insulating covers 16 and 17. Measuring the cell in its lower part is connected to the block 18 for the preparation and supply of fuel with an oxidizing agent by means of nozzles 19 and 20, the output of the combustion products is carried out through nozzle 21,

The device works as follows.

The fuel and oxidizer under investigation is fed into the combustion chamber of the measuring cell by means of the preparation and supply unit 18 via pipes 19 and 20, and the process of complete combustion of the fuel is carried out, while the combustion products are cooled in the cell to approximately the temperature of the oxidant and fuel inlet and continuously removed the environment through the pipe 21. In this case, the desired quantity of heat Qx is released in the measuring cell. At the same time, electrical signals from heat flow meters 10 and 11 are continuously input to the AAPC 13. At the same time, the SARTP 13 controls the temperature T2 of the low-inertia isothermal unit 4 by the magnitude of the signal from the Yutep flow meter so that the signal from the heat flux meter 10 is zero, and the heat output Qo released from the heater 14 of the comparative cell 9, so that the signal of the heat flux meter 11 is also zero. The amount of heat Qx from the measuring cell and Qo from the comparative cell of the calorimeter is diverted along thermal bridges 7 and 7 to the isothermal block 5, the temperature of which is Ti, and AARTP 13

maintains a constant value of the temperature Tt using a semiconductor thermopile 3. The required heat value is determined from the measured

the consumption of the investigated fuel in block 18 supplied to the combustion chamber.

The proposed device allows to reduce the time of transients in the mode of automatic control in

1.5-2 times and thereby increase the expressiveness of measuring the heat of combustion of liquid and gaseous fuels.

Claims (1)

The invention of the device for determining the heat Combustion of liquid and gaseous fuels containing an adiabatic shell with semiconductor thermopiles installed in it, a measuring cell with a burner node, a comparative cell with an electric heater, heat flow meters connected to the inlet of the automatic heat control system, the output of which is connected to the electric heater of the comparative cell, an upper isothermal unit and a lower isothermal unit in contact with the cells through thermal bridges, the unit preparation and supply of fuel and oxidizer to the measuring cell, which is different in that, in order to increase the speed of the device, it contains an additional electric a heater placed on the upper isothermal unit, heat flow meters installed without a gap between the upper isothermal unit and the upper end surfaces measuring and comparative cells, with an additional electric heater and semiconductor thermopiles connected to the output of the automatic control system heat flow, and measuring and comparative cells are placed in insulating shells. Output products burnout 21 13 AT / UUA ShchPGP Oxidizing agent  . and . - Fuel