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用沉浸法研究了球状小样品沉浸入饱和液氮时的沸腾传热规律．实验测量了降温曲线和沉浸速度，发现当球状小样品在液氮中的运动距离为５ｃｍ，沉浸速度为１～６ｍ／ｓ时，沉浸速度对沸腾过程几乎无影响，可以认为在上述实验条件下，淬冷沸腾相当于池沸腾．实验证实了用沉浸法研究小样品的淬冷沸腾传热特性的可行性．根据实验数据，提出了计算小球的最低热流密度点（Ｌｅｉｄｅｎｆｒｏｓｔ点）热流密度的拟合公式．
The immersion method was used to study the law of boiling heat transfer when a small spherical sample immersed in saturated liquid nitrogen. The cooling curve and the immersion velocity were measured experimentally. It was found that the immersion velocity has little effect on the boiling process when the spherical sample moves 5cm in liquid nitrogen and the immersion velocity is 1 ~ 6m / s. It is considered that under the above experimental conditions Quenching is equivalent to pool boiling boiling. Experiments confirmed the immersion method to study the feasibility of quenching and boiling heat transfer characteristics of small samples. According to the experimental data, a fitting formula for calculating the heat flux density at the lowest heat flux point (Leidenfrost point) of the pellet is proposed.