In this study investigations on the efficiency and agility of a liquid CO 2 cooling system, using expansion bores fed with liquid CO 2 by capillary tubes, to form a thermal seal in a magnesium hot runner channel are performed in a test rig. Via temperature measurements the performance of different sets of cooling parameters is tested and cooling rates are identified depended on a varying nozzle geometry. To validate the measurements, the tests are modelled in a thermal simulation study. The applicability of the liquid CO 2 cooling was demonstrated for engineering purposes. Adequate process times could be achieved while using a 16 mm diameter as annular gap, which results in cooling rates up to 4.8 °C/s. The tests were validated by a simulation model. The simulations illustrate the inner processes of the test rig and the comparison of temperature curves of the cooling process show a good correlation.

在这项研究中，对液态 CO 2 冷却系统的效率和敏捷性进行了调查，该系统使用通过毛细管供应液态 CO 2 的膨胀孔在镁热流道通道中形成热密封，在测试台上进行。通过温度测量，测试不同冷却参数组的性能，并根据不同的喷嘴几何形状确定冷却速率。为了验证测量结果，在热模拟研究中对测试进行建模。液体CO 2 冷却的适用性被证明用于工程目的。使用 16 毫米直径作为环形间隙可以实现足够的工艺时间，从而使冷却速率高达 4.8 °C/s。测试通过仿真模型进行了验证。