3.7.2 Experimental instruments
Gas cylinder(including one glass bottle,two pistons,rubber stopper and inflating ball),silicon pressure sensor,temperature sensor,cables,digital voltmeters and measurement monitor.
Figure 3.7.1 Structure diagram of experimental device
1—Air inlet valve;2—Pressure sensor;3—Temperature sensor;4—Air vent valve(https://www.daowen.com)
The experimental instrument is shown in Figure 3.7.1.It should be highlighted that a new type of semiconductor temperature sensor,namely AD590,is employed in this experiment with high sensitivity(1 μA/℃),good linearity and large range(-50～150℃).As displayed in Figure 3.7.2,the signal voltage is 5 mV/℃if a 5 kΩ resistor is connected to the temperature sensor in series.Then,the minimum temperature variation is 0.02℃if the resistor is connected to a digital voltmeter.In addition,the sensitivity of the pressure sensor is 20 mV/kPa with an accuracy of 5 Pa.
Figure 3.7.2 Wiring diagram of steady current source
