Abstract:

Existing techniques for heat flux field measurement are mainly limited to low resolution, slow transient response, and high cost. To solve this problem, a new technique for heat flux field measurement is proposed. Quantum dots are nanoscale photoluminescent semiconductor materials whose photoluminescence spectral intensity shows a linear trend with temperature. Based on this effect, a dual-film quantum dots sample was designed and fabricated, and an experimental system for heat flux field measurement was constructed. Through calibration and measurement experiments, the study demonstrates that the average photoluminescence intensity of the quantum dots film declines linearly with increasing temperature within the tested range. The average heat flux of the bottom during the thermal evaporation of the pure water droplet in 10s under the experimental conditions was measured to be about 3.4×10⁴W/m². And the uncertainty of the heat flux measurement was calculated to be 0.14. The spatial resolution of this method can be up to the 30μm level, and the response time is of the second level, which realizes the high-resolution and low-delay measurement of the heat flux field on the surface. Based on the advantages of high resolution and low latency, this study holds significant potential for challenging testing environments where traditional methods fall short, such as rotating blades, high-speed aircraft, and micro- and nano-components.

Key words: quantum dots, nanomaterials, heat flux, measurement, uncertainty, resolution, transient response

摘要：

现有热流密度场测量技术主要局限在分辨率低、瞬态响应慢、成本高等方面。为解决这一问题，本文提出了一种测量热流密度场的新技术。量子点是一种纳米级的光致发光半导体材料，其光致荧光光谱强度随温度的变化呈现线性变化趋势。基于该效应，设计并制作了双膜量子点试片，搭建了量子点热流密度场测量实验系统，开展了标定与测量实验。结果表明：在本研究实验范围内，量子点膜的平均光致荧光强度随温度的升高呈现线性下降趋势；测得在本研究实验条件下10s内纯水液滴受热蒸发过程中底层平均热流密度约为3.4×10⁴W/m²，测量不确定度为0.14；本研究测量方法的空间分辨率可达30μm级，响应时间为秒级，实现了对表面热流密度场的高分辨率、低延迟测量。基于分辨率高、延迟低的优势，本研究可以有效应用于旋转叶片、高速飞行器、微纳米元件等传统测量方法难以开展的测试环境。

关键词: 量子点, 纳米材料, 热流密度, 测量, 不确定度, 分辨率, 瞬态响应