Controlled temperature system for use in Ultrasound Laboratory experiments

• Grant number: 14/16371-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2014
• End date: August 31, 2015
• Field of knowledge: Engineering - Electrical Engineering - Electrical, Magnetic and Electronic Measurements, Instrumentation
• Principal Investigator: Ricardo Tokio Higuti
• Grantee: Caio César da Silva Gomes
• Host Institution: Faculdade de Engenharia (FEIS). Universidade Estadual Paulista (UNESP). Campus de Ilha Solteira. Ilha Solteira , SP, Brazil

Abstract

This project has the objective to develop a temperature control system using Peltier effect cells, which will be used for ultrasound experiments that demand controlled temperature. A styrofoam box will be used as thermal recipient, where temperature sensors and Peltier cells will be installed. A signal conditioning circuit will be implemented, whose outputs are connected to the analog-digital conversion inputs of a microcontroller. By means of an automatic control algorithm and the establishment of a reference temperature, the microcontroller will generate a pulse width modulated (PWM) signal, which will be low-pass filtered and sent to a power stage that will activate the Peltier cells, this way closing the feedback loop and controlling the temperature inside the box. It is expected that the system control the temperature in the box within a variation of 0,2oC or better. This system will be part of a larger one, for temperature stabilization intended for characterization of liquids using ultrasound. (AU)