The densities of both the vapor and liquid of
1-chloro-1,2,2,2-tetrafluoroethane along the phase
boundary
from 293 K to 395 K and in the liquid phase from 120 K to 268 K at
pressures to 4.5 MPa have been
measured. The measurements along the phase boundary curve were
made with an apparatus that allows
the simultaneous determination of liquid and vapor densities using
Archimedes' principle. The relative
measurement uncertainties of the vapor pressure and the liquid and the
vapor densities of R124 (mole
fraction of impurities: less than 0.2%) at 373 K are ±1 ×
10-4, ±5 ×
10-4, and ±1 ×
10-3, respectively.
For the measurements in the liquid single-phase region along 11
quasi-isochores at pressures up to 4.5
MPa an isochoric apparatus was used. The relative measurement
uncertainty of pv/(RT) is less than
±1
× 10-3 (95% confidence level). In
addition, the vapor pressure in the temperature range from 120 K
to
273 K was measured. Correlation equations are presented for
reproducing the vapor pressures, liquid
densities, and vapor densities. The results are compared with
those of recent publications.
An isochoric apparatus and a densimeter with a magnetic suspension coupling were used to measure the density of dry air at (10, 30, 75, and 120) kg‚m -3 . The results are compared with the Zittau database (Kretzschmar, H.-J., et al.
Purpose -The use of alternative oils for the lubrication of automobile engines has a potential of ecological and technical advantages. It requires the detailed knowledge of several thermophysical and viscosimetric properties in a large temperature range. Design/methodology/approach -For 11 different oils, the density, the heat capacity, the thermal conductivity, the viscosity at ambient pressure and the pressure-viscosity at maximal 1,000 bar have been measured. The latter has been measured with a newly developed apparatus which is described in detail. Two hydrocarbon-based factory-fill oils and nine alternative oils have been tested. Five of the alternative oils are based partly or completely on esters, the other four on polyglycols, one of them additionally on water. Findings -Data for thermophysical and viscosimetric properties are given in form of diagrams and tables. The consequences for the cooling capacity and the film forming behavior are discussed. The latter is only slightly better for the factory-fill oils, compared to the alternative oils.Research limitations/implications -The pressure-viscosity is measured at up to 1,000 bar, which is lower than the maximum pressure in the tribological contacts of an engine. Practical implications -The published data can be used to calculate tribological contacts which are lubricated with alternative engine oils or with actually used factory-fill oils. This might help to decide if esters or polyglycols are superior as engine oils. Originality/value -The results of this test program might be helpful for engineers who are interested in using alternative lubricants in tribosystems.Keywords Lubricants, Oils, Internal combustion engines, Mechanical properties of materials, Chemical properties of materialsThe authors are grateful to the German Ministry of Economics and Labour (www.BMWA.bund.de) funding the project BMWA14/02 "New lubrication concepts for environmentally friendly machines" related to thermophysical and viscosimetric properties of alternative lubricants interacting tribologically with triboreactive materials. Some of the prototype oils were supplied within the framework of the parallel ECfunded project GROWTH project No. GRD2-2001-50119, Contract No. G3RD-CT-2002-00796-EREBIO, "EREBIO -Emission reduction from engines and transmissions substituting harmful additives in biolubricants by triboreactive materials" focussing on triboreactive materials and biono-tox-properties. The supply of oils is gratefully acknowledged by the authors. The alternative bio-no-tox-lubricants were supplied by the project partners Fuchs Petrolub AG (Mannheim, Germany), Total SA (Paris, France), and Fragol Industrieschmierstoffe GmbH (Mü lheim a.d. Ruhr, Germany), a subsidiary of Fuchs and Total. Factory-fill oils used at the project partner Renault SA (Paris) were supplied by Total SA (MX1260) and Fuchs Petrolub AG (Supersyn SL PCX). Prototype oils were supplied by the same companies (Total: 100E, HCE and HCE-Low-SAP; Fuchs: Titan GT1 and GTE). All pre-blended polyglycols were suppli...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.