 experiment investig downstream influenc stagnat point mass transfer experiment investig downstream influenc stagnat point mass transfer report present experiment investig downstream influenc local mass transfer stagnat region blunt bodi hyperson flow condit coolant inject porou plug coaxial centerlin symmetri model test carri wind tunnel mach number 6 0 stagnat temperatur 1 600 stagnat pressur 600 psia gase inject rang mass flow heat transfer imperm measur isotherm wall condit higher rate mass flow adiabat surfac temperatur determin theoret analysi boundari-layer flow investig order establish similar paramet flow system paramet permit extrapol test flow condit provid laminar flow prevail helium efficaci coolant 