R/tsd.sigma1.ed2.R

In pablorcw/pwind: Package for wind energy

#' tsd.sigma1.ed2
#'
#' Turbulence standard deviation according to IEC 61400-1 Ed.2 1999
#'
#' IEC 61400-1 Wind turbine generator systems. Part 1: Safety requitrements.
#' Second Edition 1999-02.
#'
#' @param ws wind speed at the hub height (m/s)
#' @param wtc wind turbine class,
#' @param wtc = "A" - class designates the category for higher turbulence characteristic,
#' @param wtc = "B" - class designates the category for lower turbulence characteristic
#'
#' @return Function returns the standard deviation of the longitudial wind velocity component.
#' @export
#'
#' @examples tsdsigma1ed2(ws = 4, wtc = "B)
#' @examples tsdsigma1ed2()
#'
tsd.sigma1.ed2 <- function(ws = 2, wtc = "A") {
  if (wtc == "A") {
    I15 <- 0.18
    a <- 2
  } else if (wtc == "B") {
    I15 <- 0.16
    a <- 3
  } else{
    I15 <- 0
  }
  sigma1 <- I15*(15.0 + a*ws)/(a+1)
  return(sigma1)
}