Ma. Cristina M. Jamerlan (February 2010)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
Bunsen burners are commonly used laboratory gas burners. The flame temperature was controlled by adjusting the size of the air hole manually, which pose problems on accuracy. The air hole size of hole od the burner adjusted by screwing or unscrewing the air collar around the base. The flame temperature is directly proportional to the air hole size.
The system development was automated Bunsen burner with temperature control, which aimed to improve the accuracy of burner operation by automation. Its performance using a type K thermocouple as a temperature sensing device, and using the percent opening of the air hole as a means to control the flame temperature was evaluated.
The air collar was attached to stepper motor via an O–ring such that they move in a single motion. Programs were created to control the stepper motor to adjust the air hole opening of the burner using the user set target temperature and the thermocouple reading, and using the percent opening adjusted by the user.
The result of the study showed that using the percent opening values resulted to a more stable system, were the temperature reading increments range from 40 to 60 degrees Celsius. The thermocouple was not responsive enough to provide reading stable enough to control the stepper motor, and this is resulted to the unpredictable movement of the motor.
Further studies may improve the system by changing the temperature sensing element to more efficient one, and minimizing the interface of ambient air by enclosing the system.