Team Humidor

Environmental Chamber

Executive Summary

The Applied Research Laboratory at the Pennsylvania State University has proposed the task of creating a 1.5’x1.5’x1.5’ environmental chamber that can create a constant environment using temperature and humidity control from 60 deg F to 160 deg F and from 50% relative humidity to 90% relative humidity.  The tolerances are +/- 5 deg F and +/- 5% relative humidity.  This chamber will be for testing fiber-reinforced polymer-matrix composites which can be susceptible to degradation under elevated temperature and humidity.  The Chamber must perform the temperature and humidity requirements as well as being cost efficient compared to other current manufactured designs which are priced at around $6,000.

The Penn State Humidors, an engineering team consisting of Mike Garbinski, Jesse Cates, Josh Potteiger, Brent Ziegler, Ben Woods, and John Semanco, have accepted this task.  In designing the chamber, the team has looked at materials that could be selected.  Through the team’s research and taking into account rusting, corrosion, and water absorption, the stainless steel alloys of 302, 304 and 316 are available.  For the temperature control, an Omega Model RHCN-1 Temperature and Humidity controller will be used to control chamber conditions at a time response of less than 20 sec, a humidity control accuracy of +/- 2%, and a temperature control accuracy of +/- 1 ºF.  An electrical strip heater rated at 150W will be used to heat the chamber, which is based on both steady-state and transient heat transfer calculations.

The dehumidification system consists of a conventional dehumidifier, a dry air reservoir, a humidity controller/sensor, and an aquarium air pump.  The necessary flow rate of the dry reservoir air to the environmental chamber to provide a satisfactory slow dehumidification time was calculated to be between 50 mL/s to 75 mL/s.  At worst case (55% to 50% RH and 40 ºC) the fastest dehumidification rate will be 24 sec. per 1% RH, which is above the maximum 20 second response time of the humidity controller/sensor.  A 55 mL/s aquarium pump (Tetratec AP200) will be utilized in the prototype.

Throughout the designing process, progress reports will be written.  Also, a drawing of a prototype will be created along with a parts list and a design calculations report.  Finally, a working prototype will be assembled from the parts selected and ordered.  The project web page will be created and a final design report will be completed.  Lastly, The Humidors will deliver the final project to the showcase at the HUB Ballroom.

Figure 1: Environmental Chamber System

Group “A”:

Mike Garbinski

Jesse Cates

Josh Potteiger

Brent Ziegler

Ben Woods

John Semanco

Date: 12/9/03

Faculty Advisor: Savas Yavuzkurt

Sponsored by:

Eric C. Strauch

Composite Materials Division

URL: www.arl.psu.edu/capabilities/mm_cm.html