www.public4you.fora.pl

90nike5657fv

Bus Air cold Road System

Unit friction loss along the length of the friction losses along the way, said justice than friction, with p (Pa), said formula is as follows: pm = ~ - (1,4 R) () R = A / P where: A - friction factor: the average duct air velocity, s: - air duct hydraulic radius, m; A - cross-flow wind tunnel cross-section area mz: over-current cross section wind tunnel perimeter. hydraulic radius of the air duct in accordance with the calculation formula for the circular duct, as R = DI4, can get: P = A/2D formula: D - diameter of round duct, in. For rectangular duct,[link widoczny dla zalogowanych], as R = ab112 (a + b) 1 available: P, A (aI-6) v2p/4ab where the long side of rectangular duct inner side, in; 6 - short rectangular duct the inner edge of the side, in. The design of the bus duct. City buses generally round duct can be simulated to calculate the pressure loss along the way, while long-distance coach rectangular duct can be calculated along the pressure loss. Where the friction factor is more complicated to determine, usually by the following simplified formula. a. Feng Tao material sheet. Duct wall surface of the protruding part of the (absolute roughness), the average height h = 0.15mm,[link widoczny dla zalogowanych], the friction coefficient A is: A = 0.0175D2o7b. Duct board material is plastic or glass steel. When the absolute roughness = 1.0in. A value for coefficient of friction: A = 0. Ol88D. 0 - \greatly increased the flow resistance, resulting in the loss of energy,[link widoczny dla zalogowanych], such as loss of local resistance. wind channel in the tee, elbow, and import and export section to expand or shrink at will, or the speed of the air flow changes, Bureau of cloth resistance resulting in the loss. air through the pipe, diffuser pipe, reducers, damper and other parts of the resistance is generated when the flow resistance generated when the same; and air through the tee, four-way pipe and other components have resistance to flow generated by the resistance change. regardless of type of local components, it causes the loss of local resistance can be calculated by the formula △. △ / 2 where: (- local resistance factor. a variety of common tube local resistance factor can be found 3 related works duct design manual technical measures reduce the local resistance of 3.1 ~ base ■ a. measures to avoid air duct sections mutations. suddenly expanded duct section. airflow velocity change, part of the air will extend from the tube wall. the expansion of cross-section at the vortex, the formation of local resistance, resulting in energy loss. b. duct should be to minimize the turn. As air flows through Bend. air flow changes, the air from the wall of the mainstream surface, so that local area to form a vacuum, air swing in the local area. cause energy loss, and noise. In order to reduce the turn at the local coefficients, can reduce the turning radius of curvature at the transition section and reduce the number of bends. rectangular duct elbow, in addition to reducing the radius of curvature, they can also set the guiding plate inside the elbow to reduce the local resistance coefficient. c. deal with the forming of local and connecting pipe. local tube not only local resistance but also to the noise. should be fully aware of the local tube forming and connection is reasonable, and reasonably determine the additional baffle bend radius to minimize the eddy current. the general air conditioning equipment sent into the main air duct, the flow and sections have changed. The part of the vortex area will appear. In order to reduce the eddy current area. to set a number of large radius of the plate,[link widoczny dla zalogowanych], can play a role in reducing local resistance. guide plate set of more of the reduced local resistance, the better, but the addition of too much plate, difficult process. General evaporator outlet each more appropriate to install a spoiler. 3.2 technology reduces the pressure along the duct and fan measures a. connection should be reasonable. airflow in and out of fans at the required uniform. Do not have a sudden change in flow and velocity. proved inappropriate way of taking over a lot of pressure will cause the loss, the system is running in many of the problems arising therefrom, Figure 1 shows the comparative advantages and disadvantages of ways to take over the import and export. airflow outlet of the connecting pipe should be kept straight pipe, the length of the best export to the side of not less than 1.5-2.5 times (Fig. la), in order to reduce eddy current. If space constraints. outlet pipe must turn should increase the diversion board in the tube. but to pay attention to the direction we must turn down the fan impeller rotation direction (Figure 1b). Blower Inlet swirl over the connection to note. Practice Proof: installation of wind deflector will reduce the loss of about 20% a1b) way to take over the import and export advantages and disadvantages of Figure 1 Comparison 2006.1.KECHEJISHU \ More articles related to topics：

abercrombie fitch outlet The

buy ghd hair Ha Passenger Dedicated Line Project D

discount cosmetics mac HLJ6100F Type Passenger Air