论文标题
毫秒的时间尺度测量热传递到限制的He II
Millisecond Time-Scale Measurements of Heat Transfer to Confined He II
论文作者
论文摘要
我们从狭窄的，矩形的不锈钢加热器从一侧冷却的狭窄，不限制在120美元$ $ m $ m的深度的通道上，探索毫秒级时尺度上的瞬态传热。除两个横截面的两个针孔外，大约10％的通道分离出氦气。 我们在慢脉冲加热期间测量加热器条和通道氦气的温度，在9毫秒后达到峰值功率，快速脉冲加热，在100 $μ$ S后达到峰值功率，以及在100 $μ$ s后达到稳定功率的台阶加热。 使用在加热器和氦气之间的界面以及氦通道中的Gorter-Mellink传热状态下的稳态KAPITZA传热表达，我们在慢渗水测试的前5毫秒内获得了仿真和测量之间的良好一致性。取而代之的是，在kapitza表达中测得的氦气温度，我们在慢脉冲测试的前150毫秒内获得了模拟和测量的加热器响应之间的良好一致性。 同一模型无法解释加热器和氦气的快速脉冲瞬态响应，而它可以解释对应用功率的步骤的氦气响应，而不是加热器响应。因此，稳态kapitza表达可能不适用于单个毫秒内的加热事件。
We explore transient heat transfer, on the millisecond time-scale, from a narrow, rectangular stainless steel heater cooled from one side by He II confined to a channel of 120 $μ$m depth. The helium is isolated from the external bath with the exception of two pin-holes of cross section about 10% that of the channel. We measure the temperatures of both the heater strip and the channel helium during slow-pulse heating that reaches peak power after 9 ms, fast-pulse heating that reaches peak power after 100 $μ$s, and step heating that reaches steady power after 100 $μ$s. Using the steady state Kapitza heat transfer expression at the interface between heater and helium, and the Gorter-Mellink heat transfer regime in the helium channel, we obtain excellent agreement between simulation and measurement during the first 5 ms of slow-pulse tests. Using instead the measured helium temperature in the Kapitza expression, we obtain excellent agreement between the simulated and measured heater response during the first 150 ms of slow-pulse tests. The same model fails to explain the fast-pulse transient response of the heater and helium, while it can explain the helium response to a step in applied power but not the heater response. The steady state Kapitza expression may therefore not be applicable to heating events that are over within a single millisecond.
