Abstract: A wind-powered rooftop ventilator that can create both positive and negative pressures to enable the exhaust and intake of air is described. The wind-powered rooftop ventilator includes a symmetrical cap that is aerodynamically shaped such that, when wind flows against the back of the symmetrical cap, a negative pressure area is created at the front opening of the symmetrical cap, thereby enabling the exhaust of air from an indoor area. When wind flows against the front opening of the symmetrical cap, the wind is captured by the symmetrical cap, thereby enabling the intake of air into an indoor area. As such, the wind-powered rooftop ventilator can create both positive and negative pressures without use of an external power source, fan, and/or worm gear.

Abstract: Exhaust apparatus for exhausting “dirty” exhaust gases accept a core flow of such exhaust gases and combine that with an annularly-surrounding “rooftop” flow of ambient air for diluting the exhaust gases as well as expelling the diluted flow in a forcibly expelled plume in order to ensure that the “effective” expulsion distance of the expelled diluted flow is at least the physical length of the exhaust apparatus plus the gains gotten from efflux velocity and flowrate.

Abstract: Exhaust apparatus for exhausting “dirty” exhaust gases accept a core flow of such exhaust gases and combine that with an annularly-surrounding “rooftop” flow of ambient air for diluting the exhaust gases as well as expelling the diluted flow in a forcibly expelled plume in order to ensure that the “effective” expulsion distance of the expelled diluted flow is at least the physical length of the exhaust apparatus plus the gains gotten from efflux velocity and flowrate.

Abstract: Apparatus to convert LNG to gas, comprising a vaporizer having passages to pass the cool or cold LNG in heat transfer relation with warming gas flowing downwardly to discharge in multiple directions, and flow control means to control discharge of the gas flow in selected direction or directions, as a function of wind direction.

Abstract: A roof ventilator comprises a duct 1 having a symmetrical hood 3 supported at its apex 4 by bearing 10. In the absence of wind, hood 3 is spaced from the upper end 2 of duct 1 with its depending skirt 6 surrounding upper end 2 However, wind from any direction causes the hood to tilt so that skirt 6 is lowered on the windward side thus increasing the ventilation rate and thus positioning hood 3 to deflect wind and wind-borne material from the ventilator opening.