The experiments are performed within the pressure range of
11–32 MPa, mass flux of 170–800 kg m2 s1, and heat flux of
85–505 kW m2. Under each test condition, electric power in the
vertical test section is set to a certain level to maintain heat flux
at the predetermined operating condition. Pressure and mass flux
are also adjusted to certain values. The heating power of the
preheater is increased progressively to increase inlet bulk fluid
enthalpy until an abrupt increase of the wall temperature occurs,
or the vapor in the test section becomes superheated. A steady
state is assumed to be achieved when the bulk fluid temperatures
in the preheater and the test section remain nearly unchanged;
subsequently, all the measured data are collected and recorded
using a data acquisition system.