Design and characterization of an environmental test chamber for product testing in a high-temperature and humid environment

The study investigates various thermal management designs for electronic devices, alongside the design and characterization of a specialized 2 m3 test chamber for high-temperature and humid environments. The chamber was developed to evaluate the reliability of Nokia’s future products under harsh conditions. By developing a custom in-house solution rather than utilizing commercial alternatives, the study demonstrates a strategic advantage in flexibility, allowing for the precise selection of specific variables tailored to the unique testing requirements of Nokia.

The chamber’s performance was validated through a series of test cases, specifically created for demanding target conditions such as 35 °C and 90% RH. Characterization of the system revealed that while the steam generator provides rapid humidification with a calculated output of 0.68 g/s, its latency and binary operation present challenges for precise manual control. Furthermore, the study identifies significant thermal inertia caused by the heater’s casing, which continues to dissipate heat for up to 20 minutes post-deactivation.

Findings highlight that active air circulation is mandatory to prevent atmospheric stratification and the formation of localized hot spots. Experimental data confirms that without fans, the environment becomes non-homogeneous, leading to potential sensor saturation and non-reproducible results. Following the design and performance testing phases, the study discusses practical upgrades for the setup and provides a framework for implementing a particle circulation system to simulate particle environments with high-temperature and moisture.