Abstract: In a coffee making apparatus, a throughflow heater for heating water to be passed to a filter, said heater being included in a water throughflow passage extending from a water reservoir to an outlet pipe extending over said filter, is made, at least in part, of transparent material to enable the user to see whether the heater is fouled with scale deposits so that cleaning is necessary. Safety is enhanced by making the heater of transparent heat resistant glass and using one or more heating elements of the submersible type therein.

Abstract: The throttle valve comprises a swivelling plate inserted in a housing with a throughflow channel. The valve cuts off partly or completely the flow of fluid or gas media. The housing (11) has a square inlet and outlet cross-section (14,15) in the vicinity of the valve 721). The two side walls (17,18) of the throughflow channel (12) are curved outwards and displaced axially in relation to each other in the adjustment direction of the two parts (22,23) of the valve. The valve plate (21) is a rectangular plate whose height corresponds to the inner height of the throughflow channel (11), while its width is greater than the channel inner width. In the closed position the valve ends locate against the curved side walls (17,18) of the throughflow channel (11).

Abstract: Outlet connection for a water valve is designed ot reduce the noise of flow and comprises a screwed-on flow regulator mouthpiece and an associated constant throughflow control with a central perforated disc made of soft elastic material. This disc is loaded by the flow pressure and has its throughflow cross-section reduced by deformation as the flow pressure increases. The soft elastic disc (3) moves with free play on the walls inside the outlet and is pressed by the flow pressure on a rigid disc (5) which is centred in the outlet connection and supported on the jet regulator mouthpiece (2). The rigid disc has radial grooves (6) and circumferential cutouts (7) to allow the water to pass by below the elastic disc.

Abstract: The complex fluid-dynamic aspects of a turbulent recirculating flow in a cavity with axial throughflow, and a rotating wall, were investigated by adopting a simple procedure for evaluating the turbulent stresses. The flow field was divided into two regions, a core and a wall region respectively. A “wall function” was adopted in the zones near to the solid boundaries, while a constant eddy diffusivity was assumed, in the core, following the indications of computed heat transfer coefficients in comparison with existing experimental data. The distributions of the stream function and of the tangential velocity are presented for a range of the rotational Reynolds number of the rotating wall and of the Reynolds number of the throughflow.