A thermal power measuring device

Abstract

The invention discloses a thermal power measuring device. The thermal power measuring device comprises a constant temperature system, a heat measurement system, a reaction system, a heat calibration system, a gas supply system and a data collecting and control system. The constant temperature system comprises a temperature controller and a constant temperature furnace connected with the temperature controller. A heat measuring cylinder is arranged in the constant temperature furnace. A soaking block is arranged in the heat measuring cylinder. A reaction tank cavity and a reference tank cavity are formed in the soaking block and are symmetrical about the axis of the soaking block. The reaction system comprises a reaction tank sample holder and a reference tank sample holder. The calibration system comprises a reaction tank calibration sample holder and a reference tank calibration sample holder. The reaction tank calibration sample holder and the reference tank calibration sample holder respectively comprise a tubular sample rod and a soaking body II arranged at one end of the tubular sample rod. A ceramic tube is arranged in each soaking body II. A thermal resistor is wound around the ceramic tube of the reaction tank calibration sample holder. The thermal resistor is connected with four leads. The gas supply system comprises a reference gas source and a reaction gas source. The reaction tank cavity and the reference tank cavity are distributed symmetrically in the radial direction, and the influence of axial temperature change of the constant temperature furnace on the measurement of thermal power is offset.

Description

technical field [0001] The invention relates to a thermal power measurement device, which is suitable for thermal power measurement in physical and chemical processes. Background technique [0002] Chinese invention patent CN201110080073.2 discloses a thermal power measuring device. During actual use, it is found that the thermal power measuring device of this invention patent has the following technical problems: [0003] (1) The reference cell cavity in which the two reference platinum resistance wires in the temperature measurement bridge for measuring thermal power in the device are coaxially distributed in the reaction cell cavity (that is, the area where the two temperature measurement platinum resistance wires are wound) ) on both sides, while the isothermal zone in the constant temperature furnace is a section of space distributed axially around the reaction pool. The temperature of the reference pool may be lower than the reaction pool and is more susceptible to ext...

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Problems solved by technology

[0003] (1) The reference cell cavity in which the two reference platinum resistance wires in the temperature measurement bridge for measuring thermal power in the device are coaxially distributed in the reaction cell cavity (that is, the area where the two temperature measurement platinum resistance wires are wound) ) on both sides, while the isothermal zone in the constant temperature furnace is a section of space distributed axially around the reaction pool. The temperature of the reference pool may be lower than the reaction pool and is more susceptible to external influences. This uneven axial temperature will cause bridges The output thermal signal fluctuates and thus reduces the measurement accuracy of the entire device

[0004] (2) The temperature-measuring bridge as the core of the device generally inputs a constant voltage signal. Because the output signal of the bridge is proportional to the temperature coefficient of the temperature-measuring resistance, and the coefficient decreases with temperature, the output electrical signal is also Decreases with increasing temperature, which reduces the sensitivity of thermal power measurement devices and increases the error

Because the sample tube is a thin straight tube, and there are multiple accessories fixed on it, resulting in large volume and heavy weight, the process of loading the solid sample into the reaction zone in the tube and fixing it there is more troublesome

[0006] (4) The device only uses ordinary needle valves to control the gas flow during use, resulting in unstable flow and large fluctuations in thermal signals over time

[0007] (5) In this device, the thermal resistance wire used to calibrate the relationship between the thermal power to be measured and the output electrical signal (the quotient of the two is the instrument constant) is wound outside the sample tube, and the heat generated by the current passing through the calibrated thermal resistance wire is not all Heating the anti-cell cavity, part of it will escape outwards, which makes the thermal signal response generated by the actual physical and chemical process in the reaction zone not completely equal to the calibration process, and the thermal power measured by this calibration method will be greater than the actual value

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