Mathematical Investigation of Evaporation Process of Bicomponent Moving Droplet

In order to obtain the concentration, temperature and size variations of a bicomponent moving droplet during evaporation process, a mathematic based on multicomponent droplet evaporation model and droplet motion equation was developed to simulate the evaporation characteristic of a binary decane-ethanol droplet at high temperature nitrogen environment. By numerical calculations, the time evolution of internal concentration distribution within droplet was obtained, and the variations of droplet temperature and dimensionless size were analyzed. The numerical results show that: the droplet temperature variation includes transient heating and equilibrium evaporation at atmospheric pressure; while at high pressure environment, the droplet temperature increases gradually till reaches to ambient temperature. The variations of dimensionless droplet size are deviated from the d2 law due to the concentration variation during evaporation.

Research on Characteristics of Ethanol Gasoline Evaporative Emission

The chemical composition and content of evaporative emission from ethanol gasoline (E10) and gasoline were tested and analyzed by using gas chromatography mass spectrometry on-line technology in this paper. There are 27 kinds of organic compounds have been identified, they are mainly for 3-7 carbon atomics alkanes and alkenes. The results show that with the evaporation temperature rising up, the evaporative emissions relative content is increasing, the pollution to the environment is relatively aggravating, and that the evaporative emissions content in 52 0C is 3 times than in 30 0C for E10, and the evaporation characteristic is not significant difference between gasoline and E10 if we strictly control the evaporation pressure

Autostoichiometric Mocvd Of Multicomponent Thin Films LiTaO3, LiNbO3 and SrxBa1-xNbO6

A novel stoichiometric vapor deposition process, Autostoichiometric MOCVD, was developed in this study to prepare stoichiometric thin films. Heterometallic alkoxides were used as single precursor for two different metal components in Autostoichiometric MOCVD. The molecular ratios of the metals were conserved through the precursor evaporation and the deposition reactions based on the chemical nature of precursors and the deposition reaction mechanisms. A non-stoichiometric factor K was defined to study the evaporation process of precursors. A precursor evaluation method using the K factor and the thermal decomposition analysis was introduced to quantitatively analyze the stoichiometric evaporation characteristic of a heterometallic alkoxide precursor. Single phase LiTaO3, LiNbO3, SrNb2O6 and BaNb2O6 films were successfully obtained using precursor LiTa(n-OBut)6 or LiTa(i-OBut)6, LiNb(n-OBut)6, SrNb2(n-OBut)12 and BaNb2(n-OBut)12, respectively. Solid solution Sr1-x.BaxNb2O6(SBN) films were also successfully obtained by a two-step Autostoichiometric MOCVD.