inst/doc/ISO6976.2016.R

In ISO6976.2016: Calorific Values and Properties of Natural Gas per ISO 6976:2016

## ----setup, include = FALSE---------------------------------------------------
knitr::opts_chunk$set(
  collapse = TRUE,
  comment  = "#>"
)
library(ISO6976.2016)

## ----quickstart---------------------------------------------------------------
x   <- numeric(60)   # all zeros
u_x <- numeric(60)   # all zero uncertainties
r_x <- diag(60)      # identity correlation matrix (no correlations)

# Fill in a simple two-component mixture: 95 % methane, 5 % nitrogen
x[componentIndex("methane")]  <- 0.95
x[componentIndex("nitrogen")] <- 0.05

# Assign standard uncertainties (0.05 mol/mol each)
u_x[componentIndex("methane")]  <- 0.0005
u_x[componentIndex("nitrogen")] <- 0.0005

res <- calculateProperties(x, u_x, r_x,
                           combustionTemperature = 25,
                           volumeTemperature     = 15)

cat("Molar mass              :", round(res$M,   4), "kg/kmol\n")
cat("Compression factor Z    :", round(res$Z,   6), "\n")
cat("Gross CV (volumetric)   :", round(res$Hvg, 4), "MJ/m³\n")
cat("  standard uncertainty  :", round(res$u_Hvg, 6), "MJ/m³\n")
cat("Gross Wobbe index       :", round(res$Wg,  4), "MJ/m³\n")
cat("  standard uncertainty  :", round(res$u_Wg, 6), "MJ/m³\n")

## ----gascomponents------------------------------------------------------------
gc <- GasComponents$new()

# Set fractions by name or by index
gc$setFraction("methane",  0.9234)
gc$setFraction("ethane",   0.0254)
gc$setFraction("propane",  0.0152)
gc$setFraction("nitrogen", 0.0103)
gc$setFraction("carbon dioxide", 0.0154)
gc$setFraction(1L, 0.9234)   # same as "methane"

# Set uncertainties
gc$setUncertainty("methane",        0.000332)
gc$setUncertainty("ethane",         0.000243)
gc$setUncertainty("propane",        0.000148)
gc$setUncertainty("nitrogen",       0.000195)
gc$setUncertainty("carbon dioxide", 0.000111)

# Retrieve a value
gc$getFraction("methane")

# Pass directly to calculateProperties
res <- calculateProperties(gc$fractions, gc$uncertainties, gc$correlations,
                           combustionTemperature = 15,
                           volumeTemperature     = 15)
round(res$Hvg, 4)   # real-gas vol. gross CV [MJ/m³]

## ----correlations-------------------------------------------------------------
gc2 <- GasComponents$new()
gc2$setFractionArray(gc$fractions)
gc2$setUncertaintyArray(gc$uncertainties)

# Negative correlation between methane and ethane (typical for GC)
gc2$setCorrelation("methane", "ethane", -0.65)
gc2$getCorrelation("methane", "ethane")
gc2$getCorrelation("ethane", "methane")   # automatically symmetric

## ----refconds-----------------------------------------------------------------
data("example3", envir = environment())

# German/European standard: 25 °C combustion, 0 °C metering
r25_0 <- calculateProperties(example3$fractionArray, example3$uncertaintyArray,
                             example3$correlationMatrix,
                             combustionTemperature = 25,
                             volumeTemperature     = 0)

# UK/legacy standard: 15 °C / 15 °C
r15_15 <- calculateProperties(example3$fractionArray, example3$uncertaintyArray,
                              example3$correlationMatrix,
                              combustionTemperature = 15,
                              volumeTemperature     = 15)

cat("Hvg at 25/0 °C  :", round(r25_0$Hvg,  5), "MJ/m³\n")
cat("Hvg at 15/15 °C :", round(r15_15$Hvg, 5), "MJ/m³\n")

## ----coverage-----------------------------------------------------------------
data("example1", envir = environment())

r_k1 <- calculateProperties(example1$fractionArray, example1$uncertaintyArray,
                             example1$correlationMatrix,
                             combustionTemperature = 15, volumeTemperature = 15,
                             coverage = 1)
r_k2 <- calculateProperties(example1$fractionArray, example1$uncertaintyArray,
                             example1$correlationMatrix,
                             combustionTemperature = 15, volumeTemperature = 15,
                             coverage = 2)

cat("Gross Wobbe index :", round(r_k1$Wg, 5), "MJ/m³\n")
cat("  u (k=1)         :", round(r_k1$u_Wg, 6), "MJ/m³\n")
cat("  U (k=2, ~95%)   :", round(r_k2$u_Wg, 6), "MJ/m³\n")

## ----annex_d------------------------------------------------------------------
data("example1", envir = environment())
res <- calculateProperties(example1$fractionArray, example1$uncertaintyArray,
                           example1$correlationMatrix,
                           combustionTemperature = 15,
                           volumeTemperature     = 15,
                           coverage              = 1)

tab <- data.frame(
  Property = c("M [kg/kmol]", "Z", "Hcg [kJ/mol]", "u(Hcg)",
               "Hmg [MJ/kg]", "u(Hmg)", "Hvg [MJ/m\u00b3]", "u(Hvg)"),
  Computed = round(c(res$M,     res$Z,     res$Hcg,   res$u_Hcg,
                     res$Hmg,   res$u_Hmg, res$Hvg,   res$u_Hvg), 7),
  ISO_6976 = c(17.3884301, 0.99776224, 906.1799588, 0.615609872,
               52.113961,  0.024301,   38.410611,   0.026267)
)
knitr::kable(tab, align = "lrr")

## ----components---------------------------------------------------------------
# All 60 components in table order
nms <- componentNames()
cat(paste(sprintf("%2d  %s", seq_along(nms), nms), collapse = "\n"), "\n")