Device and method for measuring saturated vapor pressure

Abstract

The invention relates to a device and a method for measuring saturated vapor pressure. The method comprises the steps of firstly, starting a semiconductor chip to minimize the temperature of a quartz glass tube, vacuumizing and then directly enabling the vacuumized quartz glass tube to be connected with gas phase fluid to be measured; condensing the gas phase fluid to be measured in the quartz glass tube, and stopping the addition of liquid to be measured when the height of the fluid to be measured in the quartz glass tube is 20-80% of that of the quartz glass tube; changing the set temperature of a temperature controller, and adjusting the temperature of a soaking metal block so as to control the temperature of the fluid to be measured in the quartz glass tube; when a pressure sensor and a temperature sensor stably output signals, acquiring the temperature of the fluid to be measured and the corresponding saturated vapor pressure. After the device and the method are adopted, the whole cooling, heating and measuring processes can be completed only within 5-10min, so that the temperature control waiting time of a thermostatic bath in the traditional experiment is greatly shortened, and the measurement efficiency is increased. A circulating bath of a thermostatic bath does not need to be additionally arranged, and a sample introduction process can be realized by means of a refrigeration function of the semiconductor chip, so that the cost of a laboratory table is lowered, and the space of a laboratory is saved.

Description

technical field [0001] The invention relates to the measurement of thermophysical properties of a fluid, in particular to a device and method for measuring the saturated vapor pressure, which can be used for the teaching of courses and experiments related to energy, power and thermodynamics, and can also be used for the saturation of fluids in industry and scientific research. Measurement of vapor pressure. Background technique [0002] Saturated vapor pressure is one of the most important thermophysical properties of fluids. Saturated vapor pressure data is one of the most important parameters obtained in the field of energy and chemical engineering, and is of great significance for thermodynamic cycle and chemical process calculations. [0003] The saturated vapor pressure measuring device can be used in scientific research, industrial process measurement, and can also be used in experimental teaching of courses related to thermodynamics in colleges and universities. Amon...

AI Technical Summary

Problems solved by technology

Among them, the scientific research measurement device has a complex structure, extremely high requirements for temperature and pressure measurement, very cumbersome operation steps, and extremely expensive

In the experimental teaching of domestic colleges and universities, most of the measuring devices used are glass instrument structures, and glass instruments are relatively easy to be damaged during the process of students' hands-on installation and operation, and the structure of the experimental devices is relatively complicated.

The measuring device uses a relatively traditional glass tube thermometer for temperature measurement and a U-shaped tube manometer for pressure measurement, and the measurement method is relatively backward

Limited by the pressure resistance of glass instruments, the pressure range that the test device can test cannot be higher than the local atmospheric pressure

Scientific research and teaching experimental devices generally use a liquid constant temperature bath to control the temperature, and the measuring device is large in size, so the time to wait for the temperature to stabilize is very long. Most of the time in the experiment is wasted in the process of waiting for the temperature to stabilize, which makes the efficiency low and the measurement. low degree of automation

In addition, when the scientific research and teaching experimental devices are filled with fluid, for the low boiling point working fluid, the gas phase fluid needs to be liquefied and charged by dry ice or liquid nitrogen; for the high boiling point working medium, it needs to be filled and then cooled, and then pump Vacuum, time consuming and additional expense for dry ice or liquid nitrogen

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