Methods of calibrating torque transducers under production conditions

Measurement Techniques -     

Prediction of surface temperature rise of ultrasonic diagnostic array transducers

Temperature rise at the surface of an ultrasound transducer used for diagnostic imaging is an important factor in patient safety and regulatory compliance. This paper presents a semianalytical model that is derived from first principles of heat transfer and is simple enough to be implemented in a commercial ultrasound scanner for real-time forecasting of transducer surface temperature. For modeling purposes, one-dimensional array transducers radiating into still air are considered. Promising experimental verification data are shown and practical implementation benefits of the model for thermal design and management of ultrasonic array transducers are discussed. In particular, the reduction in the amount of thermal characterization data required, compared to empirical models, shows promise.     

Determining the weighted mean temperature of the body by means of transistor transducers

Translated from Izmeritel'naya Tekhnika, No. 7, pp. 57–58, July, 1989.     

An experimental method of determining temperature stresses by means of resistance wire transducers

Conclusions By using copper wire compensation transducers, it becomes possible to measure up to 200–250°C. To raise this limit to 400–500°C, it is necessary to make transducers of platinum wire (above 400–500°C, the temperature coefficient of resistance of nichrome wire is no longer constant).     

一体化温度变送器自动校准系统研制

针对一体化温度变送器校准工作中使用仪器繁多、连接线路复杂、数据处理工作量大等问题,研制一体化温度变送器自动校准系统。该系统包括标准恒温槽、多路数据采集装置、标准铂电阻温度计和计算机,其中多路数据采集装置将标准铂电阻配套仪表功能和直流电流表功能进行集成化设计,设置一路标准器通道和六路被校准仪器通道,可实现多支一体化温度变送器的同时校准。系统通过计算机控制程序可实现自动温度控制、温场判定、数据采集及处理以及生成校准记录等功能,且控制准确、自动化程度高。