Thermal Behavior and Power Efficiency Comparison of AC vs. DC Electrical Heating in a Distillation Column Using Infrared Thermography Analysis

The scope of my research is to demonstrate advantage of using AC and DC power supply in a heating element within a distillation column boiler. Recent studies address thermographic analysis in AC/DC powered distillation column separately, but no work combined both approaches. To begin, set up the thermal camera for acquisition.

Select the iron color palette from the thermal camera menu, and ensure it is correctly applied before proceeding. Set the emissivity correction value to 0.95 from the thermal camera menu. Then position the thermal camera approximately 80 centimeters away from the boilerplate.

Holding the thermal camera approximately 60 centimeters above the floor, orient the camera toward the boilerplate in the distillation column. Press the save button to record the thermogram to the thermal camera memory. Capture thermograms every five seconds during samples one to 1, 500 on the local interface.

Repeat the acquisition for 20, 60, and 100 volts under alternating current and direct current conditions. Record the name of each captured thermogram and the corresponding boilerplate temperature sample displayed on the local interface. To begin acquisition of boilerplate temperature data, store the temporary files generated by the local process interface.

Rename and save the stored files into the current process folder. Collect the CSV files generated during the test, and generate a single file containing all acquired process data. Save the consolidated file for analysis.

To begin preparation of the data, extract thermograms from the thermal camera. Transfer all image files to the analysis workstation. Review the extracted thermograms and discard any unwanted images.

Manually mark a reference point on each thermogram. Then create a process temperature overview graph using the previously generated process data file. Relate the boiler temperature data from the local interface to the captured process thermograms.

To develop an algorithm for thermogram processing, first load an image into a variable within the analysis environment. Define the size of the vectors for the graph axes using the image variable. Then, define the area for detecting minimum and maximum temperature ranges based on the analysis image.

Prepare the figure for graphing. Next, load the thermogram image into a variable for processing. Define a search area for the previously marked reference point.

Isolate the reference point and obtain its coordinates. Then, use the coordinates to indicate the analysis area. Now, convert the analysis area to grayscale.

Calculate the mean temperature value of the grayscale area. Isolate the maximum and minimum temperature areas in the image. Convert the graphical numbers to numeric text.

Convert the mean values to scaled maximum and minimum temperatures according to the image ranges, and store the total mean values and corresponding labels. Lastly, plot the total mean results to visualize the processed thermogram data. The temperature measurements using 100 volt DC varied throughout the process, while the measurements using 100 volt AC remained more stable.

At 100 volt DC, thermal variation across the boiler section was higher than with alternating current. DC presented more controlled areas due to smoother progression and increasing, but not abrupt dispersion. Under 60 volt conditions, temperature measurements were more stable with AC.Thermal evolution using 60 volt AC showed a gradual temperature increase during startup, whereas with 60 volt DC, the heating was more pronounced and rapid.

The graphical temperature trend at 20 volts showed noticeable variation for DC, while AC resulted in a more gradual and stable profile. Thermograms under 20 volt AC showed temperatures ranging from 22.8 degrees Celsius to 26.3 degrees Celsius. Our protocol used TIR analysis to provide a clearer view of the thermal behavior in relation to power source within the process.

Our findings show that selecting appropriate AC or DC supply optimizes performance, reduce energy costs, and improve distillation quality. Future research will investigate thermogram bases thoroughly for detection methods, and how thermal actuator fatigue influences process transient behavior.