ch_ttcoef Subroutine

subroutine ch_ttcoef(k)

~ ~ ~ PURPOSE ~ ~ ~ this subroutine computes travel time coefficients for routing along the main channel

~ ~ ~ INCOMING VARIABLES ~ ~ ~ name |units |definition ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ch_d(:) |m |average depth of main channel ch_n(2,:) |none |Manning"s "n" value for the main channel ch_s(2,:) |m/m |average slope of main channel ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

~ ~ ~ OUTGOING VARIABLES ~ ~ ~ name |units |definition ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ chsslope(:) |none |change in horizontal distance per unit |change in vertical distance on channel side |slopes; always set to 2 (slope=1/2) ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

~ ~ ~ LOCAL DEFINITIONS ~ ~ ~ name |units |definition ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ aa |none |area/area=1 (used to calculate velocity with |Manning"s equation) a |m^2 |cross-sectional area of channel b |m |bottom width of channel d |m |depth of flow fps |none |change in horizontal distance per unit |change in vertical distance on floodplain side |slopes; always set to 4 (slope=1/4) k |none |dummy argument (HRU number) p |m |wetting perimeter qq1 |m^3/s |flow rate for a specified depth rh |m |hydraulic radius of channel tt1 |km s/m |time coefficient for specified depth tt2 |km s/m |time coefficient for bankfull depth ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

~ ~ ~ SUBROUTINES/FUNCTIONS CALLED ~ ~ ~ Intrinsic: Sqrt SWAT: Qman

~ ~ ~ ~ ~ ~ END SPECIFICATIONS ~ ~ ~ ~ ~ ~

If side slope is not set in .rte file then assume this default If it is main reach default side slope to 2:1 if it is a waterway default to 8:1 check if bottom width (b) is < 0 compute flow and travel time at bankfull depth compute flow and travel time at 1.2 bankfull depth compute flow and travel time at 0.1 bankfull depth

Arguments