Faculty Advisor

Sullivan, John M.


Pressure ulcers or bedsores result in approximately 60,000 deaths each year. The frequency of pressure ulcers is correlated with stagnant activity, heat and humidity. Wheelchair bound people frequently exhibit these conditions. To address the thermally related problems involved with pressure ulcers, we designed and fabricated a self-regulating cooling pad that utilizes heat-pipe technology to cool wheelchair-confined patients. Our design is filled with an ammonia mixture that will change phase from liquid to vapor due to heat delivered by the seated person. The vapor rises naturally to the back of the wheelchair where it releases its energy to the ambient temperature environment. Our cooling device requires no external energy and can potentially reduce the frequency of pressure ulcers.


Worcester Polytechnic Institute

Date Accepted

April 2013


Mechanical Engineering

Project Type

Major Qualifying Project



Advisor Department

Mechanical Engineering