A Hybrid Mechanics of Materials Course Part 1: Evolution of the Course to Improve Student Performance and Retention

A hybrid Mechanics of Materials course consisting of recorded lecture videos and face-to-face class meetings was developed. Initial offerings of the hybrid course resulted in a drop in average student performance by – 0.18 grade points as well as a reduction in the student pass rate of 3%. Over time, average student performance in the course improved; however, the student pass rate remained relatively constant. A number of ad hoc internal studies by the hybrid course instructors were conducted to attempt to determine the factors contributing to the reduction in the student pass rate. A test over prerequisite Statics and Calculus material was developed and incorporated into the course in order to gauge incoming student capability and knowledge. Results of this pre-test provided a baseline measure so that the effect of various changes to the hybrid course could be objectively measured independent of differences in student capability. Internal studies suggested that a lack of student engagement as manifested by poor attendance in face-to-face class attendance contributed to poor performance and reduced student retention. The hybrid course policy was changed by incorporating a one letter grade penalty for students who did not have good attendance. This resulted in an improvement in average performance by 0.18 grade points and an increase in student retention by 12.5% compared to the optional-attendance hybrid course

Correlating Mechanics of Materials Student Performance with Scores of a Test over Prerequisite Material

Background – It can be difficult to differentiate the effects of curriculum and instructional changes from differences in student preparation and capabilities. Purpose – In this work we will determine whether a test over prerequisite material from Statics and Calculus can be useful in predicting performance in Mechanics of Materials courses. Method –This “pre-test” involves the application of concepts and knowledge through problem solving rather than multiple-choice questions alone. This pre-test was administered to 692 students in 19 sections taught by three different instructors over four years at Wichita State University. Conclusions – Results show that pre-test scores given at the beginning of the semester correlate reasonably well with the semester grade point where the Pearson correlation coefficient was +0.52. Students who earned a semester grade of an A averaged 87.9% on the pre-test, B students averaged 79.7% on the pre-test, C students averaged 71.2% on the pre-test, D students averaged 65.5% and students who failed or withdrew averaged 54.9%

Flow Visualization Study on the Effect of a Gurney Flap in a Low Reynolds Number Compressor Cascade

The effect of a Gurney flap in a compressor cascade model at low Reynolds number was investigated using tuft flow visualization in a water table facility. Although small in scale, water tables have the advantage of low cost and the ease with which test conditions can be varied. In this experiment, tuft flow visualization was used to determine the outgoing flow angle for a NACA 65-(12)10 compressor cascade model with a solidity of 1.5 at a blade chord Reynolds number of 16,000. The baseline (no flap) results were found to be in good agreement compared to results in the literature for tests conducted at Reynolds number in the 250,000+ range. A second set of measurements were then taken for a Gurney flap with a height of 2% of the chord length attached to the trailing edge of the cascade blades. The results suggest that the Gurney flap energizes the flow and delays the stall at large incoming flow angles