超临界压力下乳化煤油比定压热容测量 *

Measurementof Isobaric Specific Heatof Emulsified Keroseneat Supercritical Pressure

关键词:  超临界压力  乳化煤油  定压比热容  在线测量

Key words:  Supercritical pressure  Emulsified fuel  Specific heat capacity  On-line measurement

摘要:

为了准确测量高温高压下乳化煤油的比定压热容，基于能量守恒的量热计理论，搭建了一套流动型比定压热容在线测量系统。系统温度测量范围为 301～900K，测量压力可达 10MPa。通过去离子水和质量比 1:1正辛烷-正庚烷混合物对测量系统进行标定，实验结果与文献值进行比较，最大相对误差小于 ±1%，相对误差绝对平均值在 0.46%以内。在此基础上，对含水质量分数为 10%，20%，30%， 50%的四种乳化煤油比定压热容进行测量，温度为 301～880K，压力为 3MPa。实验结果与航空煤油 RP-3进行对比，结果表明:相同工况下，乳化煤油比定压热容较大，吸热能力更强，冷却壁温效果更好。该系统的搭建为进一步研究乳化碳氢燃料比定压热容创造了条件。

Abstract:

A set of constant pressure heat capacity on-line measurement system based on the energy conser.vation calorimeter theory is established in order to accurately measure the specific heat capacity of emulsified ker.osene at high temperature and pressure，which temperature covering from 301 to 900K and pressures up t 10MPa. The deionized water and the binary mixtures of n-octane and n-heptane with a mass ratio of 1:1 were measured for the calibration of the measurement system. Compared with the literature values，the experimental re.sults show that the maximum relative deviations were below ±1% and the absolute average relative deviations were within 0.46%. The isobaric specific heat capacity of emulsified kerosene with water content fraction of 10%， 20%，30% and 50% were measured at the temperatures from 301 to 880K and the pressure of 3MPa. Compared with those of aviation kerosene RP-3，the experimental results show that the isobaric specific heat capacity of emulsified kerosene is larger and the heat capacity is stronger and the effect of cooling wall temperature is better.The construction of the system creates the conditions to further study isobaric specific heat capacity of the emulsi.fied hydrocarbon fuel.