ASTM_D_7152_adjunct.xls

Description:The attached spreadsheets carry out the calculations for viscosity-blending described in ASTM D 7152,Standard Practice for Calculating theViscosity of a Blend of Petroleum Products.Summary:The Wright Blending Method calculates the viscosity of a blend of components at a given temperature from the known viscosities,temperatures,and blending fractions of the components.The Inverse Wright Blending Method calculates the blend fractions of components required to meet a target blend viscosity from the knownviscosities and temperatures of the components.The ASTM Blending Method calculates the viscosity of a blend of components at a given temperature from the known viscosities of thecomponents at the same temperature and their blending fractions.The Inverse ASTM Blending Method calculates the blend fractions of components required to meet a target blend viscosity at a given temperaturefrom the known viscosities of the components at the same temperature.For all methods,the viscosities and temperatures of the components and the blend are mathematically transformed into MacCoull-Walther-Wrightfunctions.The transformed temperatures or viscosities are summed over all components as a weighted average,with the blend fractions as theweighting factors.History:Viscosity blending equations used to be an Appendix of D 341,Standard Viscosity-Temperature Charts for Liquid Petroleum Products.They arenow published as this separate Standard Practice,with updated computations in the light of greater use of computer spreadsheet programs and thediscontinuation of the viscosity-temperature graph paper.Both the Wright Method(calculations at constant viscosity)and the ASTM Method(calculations at constant temperature)have been included.Definitions:ASTM Blending Methoda blending method at constant temperature,using components in volume percent.blend fractionthe ratio of the amount of a component to the total amount of the blend.Blend fraction may beexpressed as mass percent or volume percent.blending methodan equation for calculating the viscosity of a blend of components from the known viscosities of thecomponents.dumbbell blenda blend made from components of widely differing viscosity.inverse blending methodan equation for calculating the predicted blending fractions of components to achieve a blend of givenviscosity.mass blend fractionthe ratio of the mass of a component to the total mass of the blend.McCoull-Walther-Wright Functiona mathematical transformation of viscosity.modified ASTM Blending Methoda blending method at constant temperature,using components in mass percent.modified Wright Blending Methoda blending method at constant viscosity,using components in mass percent.volume blend fractionthe ratio of the volume of a component to the total volume of the blend.Wright Blending Methoda blending method at constant viscosity,using components in volume percent.Wright Method:Choose the viscosity units(Cell D4)For each component,enter its:Name(column C)Point 1 Viscosity(column E)Point 1 Temperature(columns H&J)Point 2 Viscosity(column K)Point 2 Temperature(columns N&P)Blend Fraction(mass or volume)(column Q)Enter the temperature at which you want the blend viscosity(Cells H20&J20)Read the blend viscosity at the desired temperature(Cell E20)ASTM Method:Choose the viscosity units(Cell D4)Choose the temperature and temperature units(Cells E4&G4)For each component,enter its:Name(column C)Viscosity at the selected temperature(column H)Blend Fraction(mass or volume)(column J)Read the blend viscosity at the desired temperature(Cell H20)Inverse Wright Method:Choose the viscosity units(Cell D4)For each component,enter its:Name(column C)Point 1 Viscosity(column E)Point 1 Temperature(columns H&J)Point 2 Viscosity(column K)Point 2 Temperature(columns N&P)Read the calculated component blend fractions(column Q)Inverse ASTM Method:Choose the viscosity units(Cell D4)Choose the temperature and temperature units(Cells E4&G4)For each component,enter its:Name(column C)Viscosity at the specified temperature(column H)Enter the desired blend viscosity(Cell H8)Read the calculated component blend fractions(column J)Note:If the components do not add to 100%,the program will pro-rate them.Viscosity of a BlendEnter the Component Names,Viscosity-Temperature Data,and PercentsWRIGHTViscosity UnitsBlending Methodmm2/sViscosity-Temperature DataComponentPoint 1Point 21 Component 15.00 mm2/s at80.00 C 30.00 mm2/sat40.00 C2 Component 212.00 mm2/s at 100.00 C#mm2/sat35.00 C3CC4CC5CC6CC7CC8CC9CC10CC11CC12CC13CC14CCBlend:30.87 mm2/s at50.00 CAreas in BLUEcan be changedThe WRIGHT methodis more accurate,butrequires viscosities attwo temperatures.TheASTM Method onlyrequires viscosity at onetemperature(to predictviscosity at onetemperature),but isnt asaccurate.Percent60.0040.00100.00Viscosity of a BlendEnter the Component Names,Viscosity-Temperature Data,and PercentsASTMViscosity Units TemperatureBlending Methodmm2/s100 CViscosity DataComponentPercent1 Component 15