共查询到19条相似文献,搜索用时 281 毫秒
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改进了Burnett法PVTx性质实验台,温度和压力测量的最大不确定度分别为±10 mK和±400 Pa。精确测量了50组HFC-143a的饱和蒸气压实验数据,提出了一个5项的HFC-143a饱和蒸气压方程,适用于161.34 K到临界温度。与文献数据比较表明,改进后的实验台精度令人满意。测量了77组HFC-236fa的饱和蒸气压实验数据,温度范围为253-396 K,压力范围为44-3064 kPa。根据本文实验结果,拟合得到了一个Wagner型饱和蒸气压方程,与文献数据进行了比较,计算得到了HFC-236fa的正常沸点和偏心因子值。 相似文献
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《工程热物理学报》2015,(9)
本文研制了一套基于自发布里渊散射法的流体音速测量实验系统,分析得到该实验系统温度、压力测量的不确定度分别为0.02 K,10 kPa,音速测量的扩展不确定度为0.5%。测量了标准物质正戊烷310 K到470 K饱和液体和350 K到470 K饱和气体的音速,与文献值比较得到,该实验测量值的测量偏差为2.5%左右,验证了本实验系统的可靠性与稳定性。在温度为303.15 K~453.15 K,压力达5.5 MPa范围内,对燃料添加剂异丙醚的饱和液体和过冷液体的音速进行了测量,并依据实验数据给出了异丙醚音速的经验关联式,关联式的计算偏差为0.51%(饱和液体)和0.54%(过冷液体)。 相似文献
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为了实现油田井下温度压力的全分布式测量,提出了一种基于光纤散射原理的分布式温度压力测量方法。该方法通过对普通光纤进行封装设计,制作成传感光纤。由于光纤传感器周围流体的温度和压力会对传感光纤内的散射光产生调制作用,通过光纤解调仪解调出光纤拉曼散射参数和布里渊散射频移就能够实现温度和压力的实时在线测量。实验结果表明:设计的分布式光纤温度压力传感器可以实现的温度测量分辨率为0.1 ℃,压力测量分辨率为0.07 MPa。基本满足油田井下温度压力测量的全分布式、实时在线、可靠性高、精度高、抗干扰能力强等要求。 相似文献
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二元物系HFC125/HFC152a的热力学性质研究 总被引:7,自引:0,他引:7
1引言二元混合工质HFC125/HFC152a臭氧破坏势为零,具有替代CFCs的潜力,也是我们所建议的三元代用混合工质HFC32/HFC125/HFC152a的二元子物系【‘」之一。迄今尚未见到关于该物系的热力学性质研究报导,本文对其进行PVTX实验研究、状态方程与混合规则关联和热力学性质计算。2实验实验在定容式PVTx实验装置上进行,测量精度为laTD528inK、IAPD51·4PPa、卜对训三0.1%和卜叫刮刀1%,采用直接观察法测量泡露点的温度和压力附加认定误差分别不超过50inK和4kPa[‘]。HFC125为美国杜邦公司提供,经天津大学分析中心分析… 相似文献
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Feng Deng Lizhi Xiao Guangzhi Liao Fangrong Zong Weiliang Chen 《Applied magnetic resonance》2014,45(2):179-192
Driven-equilibrium fast saturation recovery (DEFSR), as a new method for two-dimensional (2-D) nuclear magnetic resonance (NMR) relaxation measurement based on pulse sequence in flowing fluid, is proposed. The two-dimensional functional relationship between the ratio of transverse relaxation time to longitudinal relaxation time of fluid (T 1/T 2) and T 1 distribution is obtained by means of DEFSR with only two one-dimensional measurements. The rapid measurement of relaxation characteristics for flowing fluid is achieved. A set of the down-hole NMR fluid analysis system is independently designed and developed for the fluid measurement. The accuracy and practicability of DEFSR are demonstrated. 相似文献
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A new conformal solution theory using a single pure fluid as a reference substance for the calculation of thermodynamic properties of fluid mixtures is developed. The perturbation theory developed by Weeks, Chandler and Andersen (WCA) and by Verlet and Weis (VW) is used to calculate the reference properties. The mean density approximation and corresponding state principle are used to eliminate the higher order terms in the mixture system and to derive the pseudo-parameters for the reference system. The mixture properties are obtained from the reference properties and their corresponding hard sphere excess functions defined as the properties of the mixture less the value of the properties for the hard sphere mixture. The excess functions of mixing for several liquid mixtures of Lennard-Jones fluids, obeying the Lorentz-Berthelet rule, are calculated by the new method (VW-HSE). Comparison with the results of other theories and Monte Carlo data shows definite improvement. Since only the properties of a pure reference fluid are directly calculated, the method can be applied to more complicated multicomponent systems without additional computational effort as required by other theories. 相似文献
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WEI Gang DU Hui XU XiaoHui ZHANG YuanMing QU ZiYun HU TianQun YOU YunXiang 《中国科学:物理学 力学 天文学(英文版)》2014,57(2):301-310
A principle of generating the nonlinear large-amplitude internal wave in a stratified fluid tank with large cross-section is proposed according to the‘jalousie’control mode.A new wave-maker based on the principle was manufactured and the experiments on the generation and evolution of internal solitary wave were conducted.Both the validity of the new device and applicability range of the KdV-type internal soliton theory were tested.Furthermore,a measurement technique of hydrodynamic load of internal waves was developed.By means of accurately measuring slight variations of internal wave forces exerted on a slender body in the tank,their interaction characteristics were determined.It is shown that through establishing the similarity between the model scale in the stratified fluid tank and the full scale in the numerical simulation the obtained measurement results of internal wave forces are confirmed to be correct. 相似文献
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We have developed a new optical method to evaluate the tensio-optic behaviour of a fluid in a Couette cell. This method is based on the analysis of the phenomenon of light scattered from a laser beam passing through a sheared fluid. A phase shifting technique was added to increase the measurement accuracy and the range of possible applications. For example, with this modification the problem of low shear stresses can be analysed. This improvement enables measurements to be made even if there is less than one visible fringe. This method also allows the determination of local stresses within the fluid. For a classical Newtonian or shear thinning fluid, a linear correlation between fringe order and shear stresses is observed and the tensio-optic coefficient may then be calculated. A yield stress thixotropic fluid is also analysed to demonstrate the relevance of the developed method. This test shows two distinctive behaviours with two different tensio-optic coefficients relative to a solid state and a liquid state. 相似文献
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H. J. J. Seguin V. A. Seguin J. Dow A. K. Nath 《Applied physics. B, Lasers and optics》1984,33(4):239-241
A new type of laser calorimeter has been developed which provides high measurement sensitivity and accuracy over several decades of input radiation intensity. The approach features a rapidly spinning liquid film as the calorimetric medium, and as such can accommodate a wide spectrum of incident laser radiation, through appropriate selection of the absorbing fluid. Because of the rapidly moving thin fluid technique utilized in the construction, the calorimeter exhibits fast response, even at high or low power levels. The design concept and method of fabrication make the device quite rugged and virtually burn-out proof. 相似文献