Abstract: A coffee brewing apparatus comprising a canister for holding coffee grounds and hot water in which the coffee brews. The canister has a closable opening through which the coffee grounds and hot water are poured. A filter covers an opening at the bottom of the canister through which brewed coffee flows out of the canister. A hand pump is coupled to an opening in the canister, operable to increase air pressure inside the canister. The canister inhibits the leakage of air or liquid while the coffee is brewing. The hand pump is used to increase air pressure inside the canister to a high pressure sufficient to push the brewed coffee through the filter and out of the canister.

Abstract: A heater assembly to be located at a substantially vertical wall for heating air. The heater assembly includes one or more heating elements, and one or more heat transfer elements mounted on the heating element for transferring heat to a column of the air moving substantially upwardly past the heat transfer elements. The column includes an inner portion positioned proximal to the wall and an outer portion positioned distal to the wall. Each heat transfer element is formed to transfer substantially more heat to the outer portion of the column of the air than to the inner portion thereof, to cause the outer portion to rise faster than the inner portion, for at least partially entraining the inner portion with the outer portion, so that at least a part of the inner portion forms a laminar boundary layer flowing along the wall.

Abstract: A heater assembly to be located at a substantially vertical wall for heating air. The heater assembly includes one or more heating elements, and one or more heat transfer elements mounted on the heating element for transferring heat to a column of the air moving substantially upwardly past the heat transfer elements. The column includes an inner portion positioned proximal to the wall and an outer portion positioned distal to the wall. Each heat transfer element is formed to transfer substantially more heat to the outer portion of the column of the air than to the inner portion thereof, to cause the outer portion to rise faster than the inner portion, for at least partially entraining the inner portion with the outer portion, so that at least a part of the inner portion forms a laminar boundary layer flowing along the wall.