Hot oil temperature control unit for characterization of thermal management systems and devices

许多热管理系统和设备的精确表征，如余热回收系统、单相和两相换热器、热管和毛细抽吸回路，都需要稳定的热源和散热器。在许多应用中，使用电加热器和控制器设计可控热源是相当简单的。冷却系统的设计要困难得多，在许多情况下是使用冷却回路来完成的。对于低于环境温度的制冷应用，冷却器是必要的，而对于在高温下运行，则需要额外的加热盘管/回路。当使用水作为工质时，如通常所做的那样，冷却回路的工作温度范围被限制在饱和温度。对于100摄氏度以上的温度，系统需要在压力下运行，以防止沸腾，这可能会给设计和操作带来麻烦。此外，有几个申请者的项目同时需要在高温下加热和冷却。目前，有几家供应商提供高温控制装置，可用于为不同工艺应用的加热和冷却提供稳定的油流。这些装置通常在高达350摄氏度的温度下运行，温度稳定性为正负1摄氏度，额定功率高达100千瓦。需要资金购买这种装置，并配备必要的仪器，以确定申请者目前正在开发的几种热管理装置的特性。该装置所需的仪器将允许准确测量这些设备中的热通量和压降。这对于量化这些系统的性能和制定改进策略将是重要的。这些设备将主要供从事这些项目的研究生使用，并将显著加强他们的研究。

The accurate characterization of many thermal management systems and devices, such as waste heat recovery systems, single and two-phase heat exchangers, heat pipes and capillary pumped loops, requires stable heat sources and heat sinks. In many applications it is fairly straight forward to design controllable heat sources using electrical heaters and controllers. The design of cooling systems is much more difficult, and in many instances it is done using a cooling loop.  For cooling applications at temperatures below ambient, a chiller is necessary and for operation at elevated temperatures, an additional heating coil/loop is required. When water is used as the working fluid, as done commonly, the operating temperature range of the cooling loop is limited to the saturation temperature. For temperatures above 100 degrees C, the system needs to be operated under pressure to prevent boiling, which can be cumbersome to design and operate.  There are several projects of the applicants where both heating and cooling are required at elevated temperatures. Currently, there are several vendors that supply high temperature control units that can be used to supply a stable flow of oil for both heating and cooling for different process applications. These units typically operate at temperatures up to about 350 degrees C, with a temperature stability of plus/minus 1 degree C and power ratings up to 100 kW. Funds are requested to purchase such a unit with the necessary instrumentation to characterize several thermal managament devices that are currently being developed by the applicants. The instrumentation requested here for the unit will allow accurate measurements of the heat flux and pressure drop in these devices. This will be important to quantify the performance and develop improvement strategies for these systems. The equipment will be primarily used by graduate students working on these projects, and will significantly enhance their research.