The invention provides a liquid treatment apparatus such as a reverse osmosis apparatus wherein a portion of an inlet liquid permeates through a filter or a membrane e.g. to provide freshwater from saltwater. The apparatus comprises a pump which provides the necessary pressure of the liquid to drive the permeation process, and a recovery unit which transfers pressure of a residue quid to the inlet liquid. The pump and the recovery unit are driven at synchronous and variable speed to control the output and thereby e.g. to adjust for fouling of the filter or membrane. The invention further provides methods of controlling the synchronous speed, e.g. based on a pressure or based on the consumption of the produced liquid.
The invention concerns a control device for at least one heating, air-conditioning, ventilation or refrigeration system with a memory for a temperature control program and a signal outlet. It is endeavoured to simplify the programming. For this purpose, the memory is arranged in an element (5), which comprises a communication interface (6) and which can be dismounted from the control device, the communication interface (6) being connectable to an external input device and the control device (1) comprising an electrical supply device (3) which can transmit electrical energy to the element (5).
A multilayer composite includes at least two composites, each composite having a film and an electronically conductive layer. Several composites are laminated to provide an increased conversion between mechanical and electrical energies not only due to the multiplication of the effect of each layer, but also due to the fact that the multilayer structure itself renders the multilayer composite more rigid. In addition, the multilayer structure facilitates application of an electrical field over thinner portions of the structure, thereby requiring much less potential difference between electrodes.
The invention provides a method and a system for controlling floor heating or climate regulating systems with long time constants. According to the invention, a flow of a fluid is provided through the floor or through a similar medium with large thermal inertia. An induced heat is determined by adding up a plurality of differences between an inlet temperature of the fluid when it enters the medium and an outlet temperature of the fluid when it leaves the medium. The temperatures are sampled with a fixed sampling time and within a fixed period of time, and a corresponding change in temperature of the medium over the fixed period of time is determined. In the future, the temperature of that medium is controlled by use of a ratio between the induced heat and the change in temperature.
A device for mixing at least one first fluid and one second fluid in a micro-flow system, comprising at least two flow restrictors, a first transfer conduit in fluid communication the first og said fluids and a recipient, at least one second transfer conduit in fluid communication with the second of said fluids, the second transfer conduit having at least two fluid outlets in fluid communication with said first transfer conduit, where each of said outlets of said second transfer conduit is downstream and in fluid communication with the outlet of one of said flow restrictors, and wherein the flow restrictors are bubble-tolerant, being formed to prevent fragmentation of bubbles entering the flow restrictor, into a bubble train consuming the pressure difference between the source and the recipient. Pumping means may be attached to the flow system, possibly being constant-pressure pumps of the kind, where elastomer bladders squeeze a fluid into the channels.