Affected by factors such as load, inlet pressure, temperature and other factors, centripetal turbines are not always operated under rated conditions. At this time, the parameters such as the mass flow rate and the enthalpy drop of the radial turbine can be changed by adjusting the opening of the adjustable guide vane. To improve turbine performance under variable conditions. In the 1.5 MW class compressed air energy storage system, due to the large expansion ratio and small volumetric flow rate, a multi-stage centripetal turbine structure is used and a reheat device is added between stages. The structure is schematically shown in FIG. 1 . In order to further improve the performance of turbines in compressed air energy storage systems, researchers at the Research Center for Energy Storage R&D of the Institute of Engineering Thermophysics of the Chinese Academy of Sciences conducted related research on multi-stage reheat turbine cores with adjustable guide vanes, and achieved some progress.
The research focuses include two aspects: the influence of the adjustable guide vane on the overall characteristics of the multi-stage reheating radial turbine and the internal flow characteristics of the adjustable guide vane. In the overall characteristic impact study, the four-stage turbine was unified as a coordinate system rotation axis, and a reheater was installed before each stage of the inlet, as shown in FIG. 2 . Simulation of the reheater is achieved by the porous media loss model. The k-ε turbulence model was used for the calculation. In the study of the internal flow characteristics, in order to better obtain the boundary flow characteristics, the SST turbulence model was adopted, and the boundary conditions of the inlet and outlet boundary conditions were calculated using the overall characteristics.
The results show that when the vane opening increases, the first-stage expansion ratio decreases, the fourth-stage expansion ratio increases, the third-stage expansion ratio remains unchanged after the first increase, and the second-stage expansion ratio remains almost constant. Mass flow, total power, and guide vane opening are approximately proportional to each other. When the system load operation is required, it is easier to ensure the system aerodynamic efficiency by adopting a variable inlet pressure method than using a variable opening method, but the specific power is smaller. When the adjustable guide vane opening changes, the total pressure loss occurs mainly in the area 20% behind the passage. When the guide vane opening is reduced, the leakage flow through the tip clearance is more likely to be mixed with the mainstream of the middle part of the leaf height in the 20% area behind the guide vane, resulting in an increase in the secondary flow loss, especially at small opening degrees. Uniformity is more pronounced, leading to an increase in the entropy in the 20% area after the guide vane, as shown in Figure 3. The inhomogeneity of the outlet flow angle at both sides of the blade root and the tip of the blade also increases with the decrease of the opening.
The above research has been supported by projects such as the Youth Natural Science Foundation and the National International Scientific and Technological Cooperation Special Project. The relevant research results have been published in the Journal of China Electromechanical Engineering.
Sectional Door Accessories: motor 220V-380V, control box, spring break device, cable break device , aluminum alloy rope pulley, enhanced shaft bracket, air bag system, duplex enhanced guide wheel bracket.
Detail introduction for above main accessories
1.Motor and controller:
The garage door operator is designed for residential overhead sectional and tilt doors.
The operator memorizes the limit positions and unique braking system that slows the unit down at the end of its travel.
Rolling code remote control with max. 20 pcs hand transmitters.
The operator is equipped with a manual release lever which allows manual operation of the door in case of power failure.
The controller has a security LOCK function which prevents operation of the door from transmitter.
2.spring break device:
Sectional doors are hinged and they bend in the tracks as the door opens and closes. Many of these doors are counterbalanced with extension springs, also designated "stretch springs," and they have seven characteristics. The length is the measurement of all the coils pressed together. This, along with the inside diameter of the coils and wire size - the thickness of the wire from which the springs are made - determine the stretch, the distance the spring is extended - normally half the door height, and pull, the force the spring pulls when stretched its normal length. The type of ends determine how the ends of the spring are mounted. The initial tension is the percentage of pull needed to separate the coils. This is determined by the pitch with which the springs are wound. On sectional garage door springs this is normally 15 percent. For example a 100 pound pull spring requires 15 pounds of weight to separate the coils; when a door is open the two springs will support 15 pounds of door weight without any stretch.
Most extension springs are made of oil tempered wire. These are normally coated or painted. Some springs are made of galvanized wire.
3.able break device:
cable break device ,door hardware
adjustable bottom bracket .
the raw material hot plate
zinc plated
safety device
adjustable bottom bracket
the raw material hot plate
zinc plating
spring safety device ,2" and 3" safety device
once the cable is broken ,this devoice can keep the hurt away from the door falling
4.aluminum alloy rope pulley
Equipment: CNC stamping/punching machine, CNC bending machine, CNC cutting
machine, 5~250 tons punching machines, welding machine, polish machines...
Processed material: stainless steel: copper, carbon steel
Surface treatment: Hot galvanized, polishing
Making process:Stamping, deep drawing,bending, punching, laser cutting,threading,
welding, tapping, riveting, grinding
5.air bag system
It is a safety device. When the door is down to hit something, it will up automatically.
Operation pressure:<3mbar
Battery:CR2032*2
Battery lifetime>1 year
Emission frequency: 315MHZ
Emission power:<10mW
Receiver power source:12V
6.duplex enhanced guide wheel bracket
Determining the right type of sectional door roller for your garage door tracks can be a little confusing, especially when you do not know what you need to look for in a garage door roller. To simplify things, there are two primary things you need to be aware of. First are the actual dimensions of the roller, and second is purpose that you will be using the door for. You can read below about measuring your roller and choosing the right quality of material for your door.
Other Door Accessories,Electronic Door Accessories,Automatic Door Accessories,High Speed Door Radar Detector
Shenzhen Hongfa Automatic Door Co., Ltd. , https://www.highspeedshutterdoor.com