Evaporative cooling membrane device

A system for cooling a contained environment with a circulating stream of fluid by means of vaporation comprising:

• a) a housing with four enclosed side walls, an enclosed bottom, and an exposed face covered with at least one sheet of hydrophobic porous material of teflon of the PTFE type, said side walls including two oppositely disposed side walls one with an entrance opening and the other with an exit opening and with entrance opening capable of receiving a fluid having an elevated temperature and a predetermined flow rate and capable of experiencing a liquid to a vapor change and the exit opening capable of passing said fluid out of said housing, said predetermined flow being selected so that laminar flow is maintained from said entrance opening to said exit opening, said porous material having pores with predetermined dimensions so as to resist any fluid in its liquid state from passing therethrough but to provide passage of said fluid in its vapor state causing the evaporation of said fluid;
• b) a container defining said confined environment and capable of containing a negative pressure, said container having means for holding said housing so that said porous material is exposed to said negative pressure.