Piezoelectric pressure transduce

Piezoelectric Transducers Certain ciystals produce a potential difference between their surfaces when stressed in appropriate directions. Piezoelectric pressure transducers generate a potential difference proportional to a pressure-generated stress. Because of the extremely high electrical impedance of piezoelectric crystals at low frequency, these transducers are usually not suitable for measurement of static process pressures. 

The ballistic bomb (pressure bomb, manometric bomb) is used to study the burning behavior of a -> Gunpowder or -> Propellant charge powder. It consists of a pressure-resistant (dynamic loading up to about 1000 MPa (10000 bar) hollow steel body that can be bolted together and has a hole to adapt a piezoelectric pressure transducer. The pressure p in the bomb is measured as a function of time t. 

The evolution of the detonation wave is monitored by using high-speed piezoelectric pressure transducers and photodiodes mounted along the tube at identical axial positions. Throughout the experiments, the level of nitrogen dilution,... 

Determination of the pressure as a function of the combustion time is now mainly performed by means of piezoelectric pressure transducers. They operate such that the measured pressure that acts on their quartz-crystal measuring element via a diaphragm is transformed into a corresponding electric charge. After the electric charge is amplified, it is recorded by suitable measuring equipment. Quartz-crystal, barium titanate, and lithium sulphide can be used as the measuring elements in piezoelectric transducers. 

The piezoelectric pressure transducers m differ with respect to their design. However, most commonly in use are the piezoelectric transducers with a diaphragm, as shown in Figure 3.4a. 

Figure 3.4. Two types of piezoelectric pressure transducers (a) with diaphragm, (b) with piston...

Figure 3.6. Data acquisition and the processing system for the pressure measurement in a closed vessel by the piezoelectric pressure transducer...

Nowadays, piezoelectric pressure transducers are mainly used for the determination of the shock wave pressure in air and in water. 

Principle of the Shock Wave Pressure Determination in Air and in Water by Piezoelectric Pressure Transducer... 

The principle of the dynamic pressure determination piezoelectric pressure transducer is described in Section 3.1. In its simplest version, the measuring equipment includes a charge amplifier and a storage oscilloscope. From the voltage signal recorded on the oscilloscope, the shock wave pressure as a function of time is obtained and the shock wave impulse as well. 

The shock wave arrival is registered by suitable probes. The probes at v ich the shock wave pressure causes the change of a certain physical property are mainly used since they enable simultaneous determination of the shock wave pressure. The piezoelectric pressure transducer is mostly used. 

The pressure-time history of the interaction is recorded using four piezoelectric pressure transducers (PCB model 113A24, 5 mV/psi) flush... 

Pressure sensor selection guidelines can be found in Ref. 3. Pressure sensors have various transducers connected to them to convert the measurement into a usable signal. Strain gauges and piezoresistive and piezoelectric pressure transducers are commonly used to produce the measured values. 

Fig. 9.27 Location of piezoelectric pressure transducers (K and KW) and microphones (hy) inside and outside of the obstructed volume [15]...

Eighteen equally spaced instrument ports are located along the entire length of the test vessel. Detonation pressure is measured using flush-mounted, piezoelectric pressure transducers, with a quoted risetime of 1 microsecond. Flame time-of-arrival is measured with fast response TCs and li t sensors (e.g., photodiodes). 

Diagnostics Smoked foil, piezoelectric, pressure transducers, photodiodes, ion detectors, fast response thermocouples, gas sampling, and gas chromo to graphy Smoked foil, piezoelectric pressure transducers, photodiodes, ion detectors, fast response thermocouples, gas sampling, and gas chromotography ... 

The engine was connected to an AVL alpha 40 eddy-current dynamometer. In-cylinder pressure was taken by AVL piezoelectric pressure transducer model GU12P. Fuel line pressure was taken by a KISTLER 607C1 pressure transducer. 

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