U-shape Acoustic Liquid Densitometer

Abstract

The growing interest in measuring density of liquids has led to the need to develop new types of densitometers that can be used in several applications. The purpose of this work is to propose a simple densitometer based on measuring the frequency of created standing wave with a tube filled by a liquid under test. The developed approach is utilized to obtain a relationship between the density of some liquids and the frequency. The data acquisition and signal processing are carried out by LabVIEW software. It was shown that is a clear relationship between the frequency of standing wave created within a resonance tube in form of U-shape and the density of tested sample. This result can assist in production of cost-effective and portable densitometers.

Design, Modelling, and Experimental Validation of a Glass U-Tube Mass Sensing Cantilever for Particulate Direct-on-Line Emissions Measurement

“…For reliability of results, all combinations were repeated three times and tested at a constant temperature of 22 • C in a similar manner to research undertaken by Rechberger [23] which was monitored by a climatic chamber, as shown in the system schematic in Figure 4 and equipment setup in Figure 5. LabVIEW software was used on a laptop to measure and control the system, as implemented in similar studies [19,[44][45][46][47]. A National Instruments USB X Series Data Acquisition Device [48] was used as the interface between the physical model and the laptop.…”

A Methodology to Measure СP / CV Ratio Using U-shape Acoustic Resonance Tube

“…Their work also showed how to take into account appropriate amendments [9,10]. The main disadvantages of the method are the complexity of apparatus and the effect of the pressure inside the tube [11].…”

“…Other works [14][15][16][17] illustrate several techniques, based on acoustic measurement that are applicable to measure several physical and chemical parameters such as: density of gases, temperature, displacement and concentration. These methods are based on creating a standing wave within a resonance tube (forced or free resonance mode of operation) and then the physical phenomenon based on acoustic measurement is acquired by a microphone and signal processing is performed using LabVIEW software [16].…”

“…According to the first law of thermodynamics ∆Q=∆U+∆A (11) Consider one mole of gas, if V = const, then ∆A = 0 and, therefore, Сv = ∆U / ∆Т. If Р = const, then ∆A = Р∆V = R ∆T, since the equation of state (PV = RT) is valid in the initial and final state of the gas.…”