the pressure drop of refrigerant r-134a flow boiling inside a horizontal tube has been investigated experimentally. the test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. these instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. this system consisted of three electrically heated evapor...

systematic studies on the vapor-liquid equilibria (vle) and conductometric properties of aqueous solutions of model surface-active ionic liquid 1-dodecyl-3-methylimidazolium bromide ([c12mim]br) are performed in the absence and presence of a large series of electrolytes in order to achieve a deeper understanding about the molecular mechanism behind the specific salt effect on the aggregation be...

in this study, a generalized equation is presented to calculate vapor pressure of pure substances as a function of reduced temperature, critical pressure, and acentric factor. with the presented model, vapor pressures have been calculated and evaluated with nist data bank for 70 pure substances for about 14000 data points, and the overall average absolute percentage deviation has been only 0.78...

The pressure drop of refrigerant R-134a flow boiling inside a horizontal tube has been investigated experimentally. The test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. These instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. This system consisted of three electrically heated evapor...

The development of an estimator for vapor pressure based upon organic functional groups is described. This vapor pressure calculator permits prediction of vapor pressure for a wide range of structural classes. The statistical quality of the derived coefficients is presented as well as the quality of the prediction of the training set of compounds. The calculator is then used to predict the vapo...

In this paper, the vapor-liquid equilibrium (VLE) properties of polar and nonpolar fluids are modeled by the use of a statistically-based equation of state (EOS). The equation of state used in this work is that of Ihm-Song-Mason (ISM) EOS. An alternative approach is to revise the isothermal integration on liquid. In this respect, a temperature-dependent revision factor b (T) is introduced to th...

The enigmatic but much accepted vapor pressure paradox for oriented lipid bilayer samples was recently justified theoretically. Subsequently, recent experiments have shown that there is no vapor pressure paradox. The first result of this paper is to consider another degree of freedom that reverses the previous theoretical conclusion, so that theory and experiment are now in agreement that there...

Heavy organics deposition is a common problem in oil industry, especially in oil production, transportation and processing. Wax or solid paraffin series are examples of heavy organics that deposit. Precipitation and crystallization of wax causes major difficulties in different processes. Based on multi-solid theory, a basic model is modified in this paper for wax precipitation in different oils...

Using a GC headspace measurement technique, the vapor pressure of TATP was determined over the temperature range 12 to 60 8C. As a check on the experimental method, TNT vapor pressure was likewise computed. Values for TNT are in excellent agreement with previous published ones. For TATP the vapor pressure was found to be ~7 Pa at ambient conditions. This value translates to a factor of 10 more ...