Document Type

Conference Proceeding

Publication Date

6-24-2024

Abstract

After defining a system for analysis, a rigorous process is taught to students in their Statics and Dynamics courses on how to draw proper kinetic, free-body, and impulse-momentum diagrams. While numerous techniques and mnemonics have been mentioned in literature, any experienced instructor can tell a correct free-body diagram apart from an incorrect one. Unfortunately, this is not the case when considering scalar properties such as mass, energy, exergy, and entropy. Different fluid mechanics and thermodynamics texts have treated the diagrammatic representation of these properties either very poorly, or in the case of the latter two, not at all. In this paper, the concept of the storage and interaction diagrams is introduced as a graphical tool to represent the aforementioned scalar properties. The storage and interaction diagrams combine the conservation and accounting of extensive properties with a template similar to the kinetic, free-body, and impulse-momentum diagrams. Three examples are provided to show the application of this general diagrammatic approach to different types of problems that involve the change in multiple properties. The impact of incorporating storage and interaction diagrams when introducing conservation and accounting principles involving scalar properties is assessed through the evaluation of student performance on exams and student feedback. A comparison of two cohorts of students suggests that emphasizing drawing storage and interaction diagrams may help reduce the ramp-up time that most students need to get acclimated to the conservation and accounting principles problem-solving framework.

DOI Number / ISBN

10.18260/1-2--47998

Download

Share

COinS