A method for providing personalized comfort to occupants of an environmentally conditioned space includes sensing a pre-adjustment pressure within a variable air volume diffuser, remotely adjusting a position an individually-adjustable directional outlet of the variable air volume diffuser, sensing a post-adjustment pressure within the variable air volume diffuser, and modifying the airflow through the variable air volume diffuser such that the post-adjustment pressure is equal to the pre-adjustment pressure. The variable air volume diffuser includes individually-adjustable directional outlets and a controller configured to regulate air pressure within the variable air volume diffuser when an individually adjustable directional outlet is adjusted. A user device in operative communication with the variable air volume diffuser includes a user interface to remotely adjust an adjustable directional outlet of the variable air volume diffuser to provide personalized comfort for the user. In embodiments, the variable air volume diffuser responds to spoken commands.

A fan, in particular axial fan and preferably backward-curved radial fan, having an impeller equipped with blades, an electric motor for rotating the impeller and a device for determining the airflow when the impeller is rotating. The device for determining the airflow includes a volume flow measuring wheel arranged in the air flow, which is arranged upstream of the impeller on the inflow side. The air volume flow is calculated or derived from the rotational speed of the volume flow measuring wheel.

A constant temperature air circulation system is provided. Air valves are installed behind two three-way nodes of a main circulation loop and parallel bypasses to adjust a flowing amount of gas of each branch. When a compressor keeps a current state unchanged, a draught fan and air valves do not change. When the compressor needs to be turned on and then to be turned off, an air volume of the draught fan is adjusted, and the flowing amounts of the bypasses and a main circuit are simultaneously adjusted until the air valves that control a flowing amount of an evaporator are all closed and the air valves of the bypasses are all opened. Adjustment of the air valves and state switching of the compressor are made at the same time, so that the flowing amount flowing through a heater to a chamber is ensured to always remain unchanged.

An air conditioning apparatus includes an air vacuum pump that sucks in air from a prescribed space to place the space under negative pressure, a first hot and cool air tank that contains the sucked air, first valves that adjust the flow rate of air supplied to or discharged from the first hot and cool air tank, a second hot and cool air tank that contains the sucked air while an air flow from the air vacuum pump to the first hot and cool air tank is restricted, second valves that adjust the flow rate of air supplied to or discharged from the second hot and cool air tank, and a heating and cooling device that manages the temperature of at least one of the first and second hot and cool air tanks to which an air flow from the air vacuum pump is restricted.

A method/structure for calibrating a product fluid flow device having one or more apertures with aggregate area A.sub.o, where fluid flows along a fluid flow path therethrough in response to pressure differentials ΔP across the apertures. Calibration is effected relative to a calibration fluid flow device having a geometry and operational parameters corresponding to those of the product fluid flow device. A piecewise curved calibration controller establishes calibration conditions and generates a discrete point calibration flow rate (dpCFR) Function by measuring at a sparse set of points in a range of interest and determining a piecewise curved mathematical representation of fluid flow through the calibration fluid flow device. Data representative of the CFR function is transferred to a product blade controller, which processes the mathematical representation, and controls fluid flow through product fluid flow device based on values extracted from the received dpCFR Function.

A method for providing filtered air to a zone of a building includes operating an air handler to pass unfiltered air through a filter and output filtered air to the zone of the building. The method includes determining an amount of filtered air provided to the zone of the building by the air handler. The method includes determining if additional air filtration is required to satisfy at least one of a desired amount of clean airflow or a desired reduction of a risk of infection. The method includes activating an in-zone filtration device and operating the in-zone filtration device to draw air from the zone into an inner volume, filter the air, and recirculate the filtered air to the zone of the building in response to determining additional air filtration is required.

A fluid flow device that can measure and control a flow of a fluid is described. Various procedures, including measuring, controlling, balancing, or calibration procedures can leverage differential pressure measurement. These differential pressure measurements can be measured across the fluid flow device such that a first pressure measurement is taken upstream of the fluid flow device while a second pressure measurement is taken downstream of the fluid flow device. Moreover, one or more of the various pressure measurements, and in particular the downstream pressure measurement, can be performed at stagnation zone where the flow has stagnated. Such can provide significant amplification and/or turndown capabilities.

A fan unit reduces the number of man-hours for a preliminary test and eliminates the need for a trial run at the time of duct connection are realized. A second controller acquires: a rotation speed of a fan motor of a second fan; a volume of air, a wind speed, or front-rear differential pressure of the second fan; and an air volume target value or a wind speed target value for the second fan, and calculates a rotation speed target value Ny for the fan motor 31b by using a first function: Ny=(Qy/Qx).sup.2??Px?{m?(Qy/Qx)?Vx+p}+n?(Qy/Qx)?Vx+q. Furthermore, when the front-rear differential pressure fluctuates and the wind speed is decreased from Vt to V, the second controller calculates a rotation speed change amount to the rotation speed target value by using a second function: ?N=a?(Vt?V).

A computer and software enabled system is provided for real time and ongoing assessment and adjustment of current air quality and airflow within and exiting an operating room. Using software operating to the task of assessing existing airflow patterns in rooms of medical facilities and to determine from an optimal CFD model and a real time current CFD model one or more adjustments of the characteristics of incoming and outgoing airflow to substantially match current air flows to that of the optimal CFD model.

A solid-state sensor, including an enclosure having a first opening in a first side of the enclosure and a second opening in a second side of the enclosure, a first passageway in fluid communication with the first and second openings, and a solid-state direction sensor positioned within the first passageway. The solid-state direction sensor can include a first sensor positioned at a first axial position, a second sensor positioned at a second axial position, and a flow deflector positioned at a third axial position that is between the first and second axial positions. The flow deflector can extend into the first passageway so as to constrict the first passageway.