function [rw,hs,hw,p,T]=drstat(rs)
% compute drum water and steam properties
kdr1=49.271; kdr2=-2.137; kdr3=0.03348; kdr4=1241.7; kdr5=-21.344;
kdr6=0.21; kdr7=526.6; kdr8=31.044; kdr9=-0.6209;
rs2=rs*rs;
rw=kdr1+kdr2*rs+kdr3*rs2;
hs=kdr4+kdr5*rs+kdr6*rs2;
hw=kdr7+kdr8*rs+kdr9*rs2;
p=459.41+358.61*rs-12.04*rs2;
T=616.75+6.691*rs+459.67;
end