Relationship of PVT conditions and specific heat capacity of oils for thermodynamic measurements
Abstract
The relative density function of an oil chosen as a reference from 24 oils is found to describe the pressure/temperature dependence of the density of the individual oils to within + or - 0.5%. A smaller sample of oils indicates a similar function for the temperature dependence of the specific heat. The relative specific volume and a coefficient for evaluating the cubic expansion energy of isentropic processes are calculated for the reference oil. Inaccuracies from the application of these quantities to the other oils are included in considering total errors of thermodynamic measurements in pumps and motors. Determination of efficiency is possible to within + or - 1% when temperatures are known to within + or - 0.01 K and the pressure difference is greater than 50 bar.
- Publication:
-
Unknown
- Pub Date:
- September 1978
- Bibcode:
- 1978rmso.rept.....K
- Keywords:
-
- Density Measurement;
- Oils;
- Specific Heat;
- Thermodynamic Properties;
- Accuracy;
- Pressure Effects;
- Temperature Effects;
- Thermal Expansion;
- Thermodynamic Efficiency;
- Thermodynamics and Statistical Physics