scholarly journals A Pulse Method for Measuring Small Changes in Ultrasonic Velocity in Solids with Temperature

1948 ◽  
Vol 20 (4) ◽  
pp. 590-590 ◽  
Author(s):  
Richard D. Holbrook
Keyword(s):  
Ultrasonic Velocity ◽  
Pulse Method

scholarly journals Creation of Pulse Method for Measurement of Ultrasonic Velocity with High Accuracy

2021 ◽  
Vol 19 (2) ◽  
pp. 13
Author(s):  
V V Muravyov ◽  
D V Zlobin ◽  
T I Zemskov ◽  
G V Bezruchenkov ◽  
V V Syaktereva
Keyword(s):  
Ultrasonic Velocity ◽  
Pulse Method ◽  
High Accuracy

В статье обсуждаются способы высокоточного определения скорости ультразвука в твердых материалах. Описана методика проведения точных измерений временных интервалов ультразвуковых импульсов, приведена блок-схема экспериментальной установки. Установка построена на широкодоступных компонентах, возможна ее простая модернизация. Предложено использование датчика на основе сегнетоэлектрического полимера поливинилиденфторида в качестве источника излучения и приема продольных волн. В качестве объектов контроля используются концевые меры длины и ступенчатый образец из стали, изготовленный с использованием плоскошлифовального станка. Представлены результаты определения скорости, подтвержденные многократными измерениями на ступенчатом объекте с разницей по толщине ступеней 10 мкм. Проведен эксперимент при изменяемой температуре образцов концевых мер длины, подтверждающий точность измерений и разницу в рассчитанной скорости, свидетельствующий о разном структурном составе объектов. Определен химический состав образцов концевых мер длины с использованием рентгено-флуоресцентного анализатора. Представлен график зависимости плотности объектов от скорости ультразвука. Описаны погрешности измерений, способы их расчета, в частности временная задержка при использовании пленочного датчика. Абсолютная погрешность определения скорости ультразвуковых продольных волн не превышает 2 м/с, что позволяет фиксировать крайне малые отклонения скорости ультразвука в образцах.

Main features of using the shock pulse method for vibration diagnostics of turbogenerator stators

2018 ◽  
Vol 11 (1) ◽  
pp. 36-40
Author(s):  
S. N. Gavrilov ◽  
A. V. Gaev ◽  
V. I. Nikitin ◽  
G. D. Pigrova
Keyword(s):  
Pulse Method ◽  
Shock Pulse ◽  
Vibration Diagnostics

MODELING OF THE DYNAMIC PROCESS RELEASE OF STUCK DRILLING TOOLS BY HYDRO-PULSE METHOD

2019 ◽  
pp. 94-103
Author(s):  
K. H. Levchyk ◽  
M. V. Shcherbyna
Keyword(s):  
Mathematical Model ◽  
Dynamic Process ◽  
Drilling Fluid ◽  
Pulse Method ◽  
Geometrical Parameters ◽  
Technical Solution ◽  
Rock Layer ◽  
Drilling Tool ◽  
Drilling Tools ◽  
Drill Pipes

A technical solution is proposed for the elimination the grabbing of drilling tool, based on the use of energy due to the circulation of the drilling fluid. The expediency eliminating the grabbing drilling tool using the hydro-impulse method is substantiated. A method of drawing up a mathematical model for the dynamic process of a grabbing string of drill pipes in the case of perturbation of hydro-impulse oscillations in the area of the productive rock layer is developed. The law of longitudinal displacements arising in the trapped string is obtained, which allows choosing the optimal geometrical parameters of the passage channels and the frequency rotational of shutter for these channels. Recommendations for using this method for practical use have been systematized.

Method and tools for determining heat transfer coefficients in organic liquids and solutions

2020 ◽  
pp. 45-55
Author(s):  
Aleksandr S. MYAKOCHIN ◽  
Petr V. NIKITIN ◽  
Sergey Yu. POBEREZHSKIY ◽  
Anna A. SHKURATENKO
Keyword(s):  
Heat Transfer ◽  
Experimental Studies ◽  
Pulse Method ◽  
Organic Liquids ◽  
Transfer Coefficients ◽  
Resistance Thermometer ◽  
Film Sensor ◽  
Heat Transfer Coefficients ◽  
Aerospace Technology ◽  
New Generation

The paper presents a method, tools and a newly developed algorithm for experimentally determining heat transfer coefficients in organic liquids and solutions. This work is made relevant by the problem of development of a new generation of aerospace technology. In this connection, improvements have been made to the pulse method of determining heat transfer coefficients that is based on the use of a micron-thick film sensor. The measurement setup was modified. A math model was constructed for the measuring sensor. Algorithms were developed for conducting the experiment and processing measurement results to determine heat transfer coefficients. Experimental uncertainties were analyzed. The paper provides results of experimental studies on certain organic liquids. The authors believe that the material presented in the paper will find application in research conducted at research institutions, engineering offices and universities, among researches, postgraduates and students. Key words: thermal and physical characteristics, organic liquids and their solutions, film-type electrical resistor, thin-film temperature sensor, voltage pulse, resistance thermometer, irregular heat transfer regime.

Performance of Ag-HZSM-5 Zeolite Catalysts in n-heptane Conversion

2017 ◽  
Vol 68 (1) ◽  
pp. 116-120
Author(s):  
Iuliean Vasile Asaftei ◽  
Neculai Catalin Lungu ◽  
Lucian Mihail Birsa ◽  
Ioan Gabriel Sandu ◽  
Laura Gabriela Sarbu ◽  
...  
Keyword(s):  
Aromatic Hydrocarbons ◽  
Metal Content ◽  
Pulse Method ◽  
Acid Strength ◽  
Strength Distribution ◽  
Zeolite Catalysts ◽  
Benzene Toluene ◽  
Acid Strength Distribution ◽  
Silver Cations ◽  
Heptane Conversion

The conversion of n-heptanes into aromatic hydrocarbons benzene, toluene and xylenes (BTX), by the chromatographic pulse method in the temperature range of 673 - 823K was performed over the HZSM-5 and Ag-HZSM-5 zeolites modified by ion exchange with AgNO3 aqueous solutions. The catalysts, HZSM-5 (SiO2/Al2O3 = 33.9), and Ag-HZSM-5 (Ag1-HZSM-5 wt. % Ag1.02, Ag2-HZSM-5 wt. % Ag 1.62; and Ag3-HZSM-5 wt. % Ag 2.05 having different acid strength distribution exhibit a conversion and a yield of aromatics depending on temperature and metal content. The yield of aromatic hydrocarbons BTX appreciably increased by incorporating silver cations Ag+ into HZSM-5.

Laboratory Evaluation of the Dual-Probe Heat-Pulse Method for Measuring Soil Water Content

2003 ◽  
Vol 2 (3) ◽  
pp. 389
Author(s):  
J. M. Basinger ◽  
G. J. Kluitenberg ◽  
J. M. Ham ◽  
J. M. Frank ◽  
P. L. Barnes ◽  
...  
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Pulse Method ◽  
Heat Pulse ◽  
Laboratory Evaluation ◽  
Dual Probe

Oxidation of Ethanol on Sn-Mo Oxide Catalysts

1992 ◽  
Vol 57 (3) ◽  
pp. 439-445
Author(s):  
Magdy A. Wassel ◽  
Nalla K. Allahaverdova ◽  
Tofki G. Alkhazov
Keyword(s):  
Acetic Acid ◽  
Potassium Hydroxide ◽  
Pulse Method ◽  
Conversion Ratio ◽  
Mo Catalyst ◽  
Acid Ratio ◽  
Aqueous Potassium Hydroxide ◽  
The Stability ◽  
Primary Oxidation ◽  
Oxidation Of Ethanol

To determine the acidic and basic properties of the title catalysts, the adsorption of NH3 and SO2 was compared using pulse method. It was found that this characteristics undergoes changes when the Sn-Mo catalyst is treated with aqueous potassium hydroxide solutions of different concentrations. The catalyst treated with the more concentrated KOH solution possesses mainly properties of a base. When studying the oxidation of ethanol it has been found that the αCO2/αaldehyde conversion ratio increases with the time of contact of the mixture with the catalyst while the αCO2/α acid ratio is not affected. The study of two alcohols deuterated either in OH group (C2H5OD) or in the alkyl group ((C2D5OH) has shown that the substitution of C-H for C-D bond enhances the stability of the primary oxidation product, deuterated ethanal, so that it is not transformed further to acetic acid.

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