Showing papers by "Nagai Makoto published in 2001"

Centrifugal air blower and air conditioner

Abstract: PROBLEM TO BE SOLVED: To provide a centrifugal air blower and an air conditioner for reducing an electromagnetic vibration sound, having high reliability, reducing a cost, and superior air blowing performance. SOLUTION: This centrifugal air blower is provided with an impeller having a boss 2 provided with a motor rotary shaft installing hole 6, a hub 3 on the outer periphery of the boss 2, a plurality of blades 4 arranged in the circumferential direction on the surface of the hub 3, and a shroud 5 arranged on the side opposed to the hub 3 by sandwiching the blades 4, and a motor for fixing a motor rotary shaft to the boss 2, and rotating the impeller. A plurality of slits 8 are arranged in the circumferential direction between the boss 2 of the hub 3 and the blades 4.

Design support device for air-cooling machine

Abstract: PROBLEM TO BE SOLVED: To provide a design support device which can evaluate the performance of an air-cooling machine in a short time with high precision. SOLUTION: This device includes a preprocessor (101) which generates an analytic model including a grating for numerical analysis and a boundary condition, a fluid analytic solver (102) which calculates the air velocity vector at an evaluation point in the generated analytic model, databases (103 and 104) which previously find and store the correlation among the air velocity vector, noise, and heat exchange quantity at the evaluation, and a noise and heat- exchange performance calculation part (105) which calculates the noise and heat-exchange performance of the air-cooling machine according to the calculated air velocity vector and the correlation stored in the databases.

Air-conditioning device and outdoor machine thereof

Abstract: PROBLEM TO BE SOLVED: To improve air supply performance of an outdoor machine and to reduce the generation of air supply noise, in an air-conditioning device for a domestic use and an industrial use. SOLUTION: This outdoor machine comprises a heat-exchanger 14, a fan motor 16, a fan 10 and a fan guide 11. In this case, the blade of the fan 10 is inclined in an air supply direction or the fan 10 having the tip central part of a blade on the air supply side situated in an air supply direction from the root central part of the blade is used. By increasing a distance between the fan 10 and the guard 11, the generation of guard noise is reduced. Further, the fan guide 11 is formed in a shape that the fan side in a grill section cut in a shape concentric to a fan rotary shaft is curved in a protrusion toward a fan rotation direction. This constitution recovers a peripheral speed by rotation of a fan as a pressure and improves air supply performance.