|
Specific Fan Power
Specific Fan Power (SFP) is a parameter that quantifies the energy-efficiency of fan air movement systems. It is a measure of the electric power that is needed to drive a fan (or collection of fans), relative to the amount of air that is circulated through the fan(s). It is not constant for a given fan, but changes with both air flow rate and fan pressure rise. Definition SFP for a given fan system and operating point (combination of flow rate and pressure rise) is defined as: :SFP = where: * is the electrical power used by the fan (or sum of all fans in the ventilation system) W* is the gross amount of air circulated through the fan (or ventilation system) 3/s There are various sub-definitions of SFP for different specific applications, including SFPe (building energy performance calculations), SFPv (for performance verification tests), SFPi (individual fan), SFPAHU (air handling unit), SFPFCU (fan coil unit), and SFPBLDG (whole building). These are explained in and in part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Total Pressure
In physics, the term total pressure may indicate two different quantities, both having the dimensions of a pressure: For compressible flow the Isentropic nozzle flow#Supersonic flow, isentropic relations can be used (also valid for incompressible flow): : p_t=p\left(1+\fracM^2\right)^{\frac{\kappa}{\kappa-1 At Standard_temperature_and_pressure, standard conditions the scientific community usually takes M<0.3 as the threshold to compressibility. Flows with a higher Mach number cannot approximate the total pressure using the incompressible formula given above. At non-standard conditions the flow may be considered compressible at lower Mach numbers. An example would be a flow through a long insulated pipe where wall friction is not neglected. Then the flow's temperature increases farther down the pipe and must be considered compressible after some length. The higher the pressure and temperature are, the less good the incompressible formula becomes. At standard ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fan (mechanical)
A fan is a powered machine used to create a flow of air. A fan consists of a rotating arrangement of vanes or blades, generally made of wood, plastic, or metal, which act on the air. The rotating assembly of blades and hub is known as an ''impeller'', ''rotor'', or ''runner''. Usually, it is contained within some form of housing, or case. This may direct the airflow, or increase safety by preventing objects from contacting the fan blades. Most fans are powered by electric motors, but other sources of power may be used, including hydraulic motors, handcranks, and internal combustion engines. Mechanically, a fan can be any revolving vane, or vanes used for producing currents of air. Fans produce air flows with high volume and low pressure (although higher than ambient pressure), as opposed to compressors which produce high pressures at a comparatively low volume. A fan blade will often rotate when exposed to an air-fluid stream, and devices that take advantage of this, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Industrial Fans
Industrial fans and blowers are machines whose primary function is to provide and accommodate a large flow of air or gas to various parts of a building or other structures. This is achieved by rotating a number of blades, connected to a hub and shaft, and driven by a motor or turbine. The flow rates of these mechanical fans range from approximately to per minute. A blower is another name for a fan that operates where the resistance to the flow is primarily on the downstream side of the fan. Functions and industries There are many uses for the continuous flow of air or gas that industrial fans generate, including combustion, ventilation, aeration, particulate transport, exhaust, cooling, air-cleaning, and drying, to name a few. The industries served include electrical power production, pollution control, metal manufacturing and processing, cement production, mining, petrochemical, food processing, cryogenics, and clean rooms. Centrifugal fans and axial fans Most industrial f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Pump Power
Specific Pump Power (SPP) is a metric in fluid dynamics that quantifies the energy-efficiency of pump systems. It is a measure of the electric power that is needed to operate a pump (or collection of pumps), relative to the volume flow rate. It is not constant for a given pump, but changes with both flow rate and pump pressure. This term 'SPP' is adapted from the established metric Specific fan power (SFP) for fans (blowers). It is commonly used when measuring the energy efficiency of buildings. Definition The SPP for a specific operating point (combination of flow rate and pressure rise) for a pump system is defined as: :SPP \equiv where: * is the electrical power used by the pump (or sum of all pumps in a system or subsystem) W* is the volumetric flow rate of fluid passing through the pump (or system) 3/s Some countries use /s Just as for SFP (i.e. fan power), SPP is also related to pump pressure (pump head) and the pump system efficiency, as follows: :SPP = where: * \ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Efficient Energy Use
Efficient energy use, sometimes simply called energy efficiency, is the process of reducing the amount of energy required to provide products and services. For example, insulating a building allows it to use less heating and cooling energy to achieve and maintain a thermal comfort. Installing light-emitting diode bulbs, fluorescent lighting, or natural skylight windows reduces the amount of energy required to attain the same level of illumination compared to using traditional incandescent light bulbs. Improvements in energy efficiency are generally achieved by adopting a more efficient technology or production process or by application of commonly accepted methods to reduce energy losses. There are many motivations to improve energy efficiency. Decreasing energy use reduces energy costs and may result in a financial cost saving to consumers if the energy savings offset any additional costs of implementing an energy-efficient technology. Reducing energy use is also seen as a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventilation Fans
Ventilation may refer to: * Ventilation (physiology), the movement of air between the environment and the lungs via inhalation and exhalation ** Mechanical ventilation, in medicine, using artificial methods to assist breathing *** Ventilator, a machine designed to move breathable air into and out of the lungs * Ventilation (architecture), the process of "changing" or replacing air in any space to provide high indoor air quality * Ventilation (firefighting), the expulsion of heat and smoke from a fire building * Ventilation (mining), flow of air to the underground workings of a mine of sufficient volume to dilute and remove noxious gases See also * Heating, ventilation, and air conditioning, the technology of indoor and vehicular environmental comfort * Mechanical fan * Reebok Ventilator Reebok Ventilator is a line of athletic shoes by Reebok. The footwear was first introduced in 1990 as a lightweight sneaker with vented side panels. The Ventilators focused on "breathability" wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heating, Ventilation, And Air Conditioning
Heating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation as HVAC&R or HVACR, or "ventilation" is dropped, as in HACR (as in the designation of HACR-rated circuit breakers). HVAC is an important part of residential structures such as single family homes, apartment buildings, hotels, and senior living facilities; medium to large industrial and office buildings such as skyscrapers and hospitals; vehicles such as cars, trains, airplanes, ships and submarines; and in marine environments, where safe and healthy building conditions are regulated with respect to temperature and humidity, using fresh ai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Motors
An electric motor is an electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a wire winding to generate force in the form of torque applied on the motor's shaft. An electric generator is mechanically identical to an electric motor, but operates with a reversed flow of power, converting mechanical energy into electrical energy. Electric motors can be powered by direct current (DC) sources, such as from batteries, or rectifiers, or by alternating current (AC) sources, such as a power grid, inverters or electrical generators. Electric motors may be classified by considerations such as power source type, construction, application and type of motion output. They can be powered by AC or DC, be brushed or brushless, single-phase, two-phase, or three-phase, axial or radial flux, and may be air-cooled or liquid-cooled. Standardized motors provide c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
