T-shirt with propping effect for natural ventilation : design development and evaluation of its functionality by thermal manikin in standing and walking motions

To improve the natural ventilation of garments is often a crucial task in designing functional garments. Normally, the ventilation can be improved by using appropriate types of fabric, or applying functional design details such vented panels on certain parts of a garment. Apart from these two means, are there any other alternative ways that clothing designers can utilize? Designing is a means to solve problems. Through a patent search, it was found that some inventors have adopted different means of designing to improve natural ventilation. Putting mesh panels on the garments was the most common way to achieve such aim. This design method had been proven by scholarly researches on its contribution on heat and moisture transfer. In addition, some designers noted that the air gap between the garment and body could be a key to affect such natural ventilation. For example, Moretti proposed putting additional spacer objects under the shoulder areas to create a gap so as to improve the natural ventilation of the wearer. Although this new design was claimed to have contribution to enhance natural ventilation for the wearer, the testing results were not provided. In this study, T-shirt designed with larger air gaps on the shoulders was developed. In order to test the effectiveness of this design method on heat and moisture transfer, a series of testing were conducted by using a movable thermal manikin in a chamber with the control of temperature and relative humidity. In order to test the functionality of the chimney/pumping/ventilation effect, the testing was conducted under no wind and windy conditions with a thermal manikin in a standing position, and under a simulated “walking” motion (walking speed of 1.24 km/h). The test results showed that the T-shirt with a larger air gap on the shoulders can significantly improve moisture vapor resistance during windy conditions.