In the practical application of temperature test chambers, the thermal load on the temperature uniformity of the interference is mainly manifested in the test samples of their own heat on the box air convection and heat transfer system perturbation. For this technical problem, temperature test chamber users can realize accurate control through the following systematic measures:

First, load characterization and equipment selection to match the temperature test chamber selection stage, you need to clearly distinguish between the non-heating load and heating load characteristics of the difference. For the non-heating load, temperature test chambers need to consider the impact of its response speed of the temperature control system; and heating load will significantly change the box thermodynamic equilibrium state. It is recommended to use the temperature test chamber with dynamic thermal compensation function, through the equipment manufacturer to provide the heat load calculation model, select the box volume and cooling capacity configuration in line with the sample heating power.

Second, the optimization of the sample layout in the temperature test chamber in the temperature test chamber, the spatial distribution of the sample directly affects the uniformity of the temperature field. Should follow the “three-zone principle” for the layout: from the box wall to maintain 10cm buffer zone, the sample spacing to maintain 15cm convection zone, the top to retain 20cm air duct area. It is strictly prohibited to heat samples placed in the temperature test chamber duct circulation weak area, it is recommended that the use of layered grid fixtures to achieve a balanced distribution of heat sources.

Third, temperature test chamber load dynamic control temperature test chamber refrigeration system needs to be dynamically matched with the heat load. It is recommended that the configuration of intelligent power regulation module, when the sample is detected instantaneous heat exceeds the preset threshold, automatically enhance the compressor output power and optimize the damper opening. For continuous heat load, temperature test chamber should be equipped with a secondary pre-cooling system, through the feed-forward control algorithm to compensate for thermal disturbances in advance.

Fourth, temperature test chamber thermodynamic system optimization Using three-dimensional circulation duct design of temperature test chamber can significantly improve the temperature uniformity. Through the setting of adjustable deflector, frequency centrifugal fan and partition temperature sensor, to realize the active regulation and control of the heat flow field inside the box. For high heat load scenarios, it is recommended to use double evaporator structure of the temperature test chamber, through the independent control of two sets of refrigeration systems to achieve accurate temperature field regulation.

Fifth, temperature test chamber thermal insulation performance enhancement Upgrade the composite thermal insulation layer structure of the temperature test chamber, the use of vacuum insulation board (VIP) and aerogel composite material combination program, the test chamber body heat leakage rate is reduced to less than 3W/m² -K. For the door sealing system, high and low temperature test chamber should be equipped with magnetic fluid sealing and infrared thermal imaging self-test device, real-time monitoring of sealing performance and automatic compensation.