Experimental Study of the Density and Viscosity of $$n$$ -Heptane at Temperatures from 298 K to 470 K and Pressure upto 245 MPa

CHAPTER 1. Volumetric Properties: Introduction, Concepts and Selected Applications

“…[149][150][151][152][153][154][155][156] Liquid heptane (n-C 7 H 16 ) is a key hydrocarbon liquid in thermophysics. Using a new apparatus for simultaneous measurements of the density and viscosity of liquids at high temperatures (from room temperature to 500 K) and high pressures (up to 250 MPa) based on hydrostatic weighing and falling-body techniques, respectively, Sagdeev et al 157 recently presented a comprehensive experimental study of this liquid.…”

Densities and Viscosities of Oleic Acid at Atmospheric Pressure

“…As part of continuing studies (Sagdeev et al, , , , , , ; Usmanov et al, ) of the effect of temperature and pressure on the thermophysical properties of working fluids, the density and viscosity measurements were made for oleic acid, using a modified hydrostatic weighing densimeter (HWD), over a wide temperature range at atmospheric pressure. The HWD was used in our previous publications for accurate measurements of the density and viscosity of pure liquids (Sagdeev et al, , , , , , , , , ) and liquid mixtures (Sagdeev et al, , , , , , ) at temperatures from (273.15 to 413.15) K and at pressures up to 140 MPa. Recently, (Sagdeev et al, ) a modified HWD instrument was employed to measure density of high‐viscosity working liquids for diffusion vacuum pumps over a wide temperature range (273 to 473) K at atmospheric pressure.…”

Confined fluid density of a pentaerythritol tetraheptanoate lubricant investigated using molecular dynamics simulation

“…Density widely appears in the fundamental equations of hydrodynamic lubrication. The value of density is necessary to determine the experimental dynamic film thickness and viscosity of a lubricant [1,2]. For most engineering applications and designs, liquids are considered incompressible to facilitate solving the hydrodynamic equations, but in nanoscale hydromechanics and thin film lubrication mechanics, the density variation of a lubricant cannot be neglected, as it significantly influences the tribological behavior of the lubricant [1,3].…”

“…Both experimental and theoretical studies have indicated that the properties of thin film lubrication (TFL) cannot be determined by classical theories [1][2][3][4]. As film thickness approaches nano and molecular scales, the well-established continuum theories and the hypothesis of uniform density distribution in the direction of film thickness fail to be valid.…”

“…(5) Subscripts i, j, ij atomic index nonbond nonbonding interaction bond, angle, dihed, impro intramolecular interaction [19][20][21][22]. Examples of the few MD studies on liquid compressibility use simple hard-sphere fluid models [23], dissipative particle dynamics investigations [24], coarse-grained bead-spring models, and normal alkane models [2,[25][26][27][28].…”