Optimized Fan Blade Designs for Noise Reduction in HVAC Systems

Fan and air conditioner with reduced noise compared to conventional designs by using a folded structure at the fan inlet to smoothly transition airflow into the guide. The fan has a flow guiding device with a current collector, throat, and diffuser. The inlet end of the collector has a flange structure with an angled folded edge to pre-guide airflow. This avoids abrupt changes and noise from sudden speed and direction changes.

Blower design with a diffuser to convert the direction of airflow discharged by the fan into ascending airflow. This allows the blower to efficiently move air vertically without needing a separate upward fan or ducting. The diffuser extends vertically from the fan outlet and guides the air upward. It reduces noise and flow separation compared to conventional rising airflow generators. The diffuser shape and angles are optimized to balance noise reduction and efficiency.

Reducing the rotational inertia of impellers in fans and air conditioners to improve stability and reduce noise. The fan design involves mounting the impeller on both ends instead of just one. This reduces the moment of inertia compared to traditional fans where the impeller is suspended from one end. The impeller has a first connection point to the motor mounting plate and a second connection point to the housing. This configuration reduces the weight at one end and lowers the overall rotational inertia. The air conditioner incorporates this fan design inside the second housing.

An air chamber with an adjustable element for regulating and directing air flow in HVAC systems that generates low noise and allows easy adjustment. The chamber has an input opening and at least one output opening, with an adjustable element inside. The element includes a tiltable wing inside the chamber body that can rotate between extreme positions. The wing has edges that contact the chamber walls or neighboring wings when tilted. This allows air to flow over the wing surface instead of through it. The wing's longer length and rotation path reduce noise compared to prior throttles. The wing rotation is synced by a slider and draw rods mechanism.

Air conditioner indoor unit with improved airflow and reduced noise compared to conventional units. The unit has a cross flow wind wheel, air guide blades at the outlet, and blocking ribs on the connecting rod. The ribs prevent air from reversing and causing discontinuous backflow at the outlet. This eliminates surge noise and improves user experience. The ribs form rectangular plates extending along the blade width. They connect outward from the rod and prevent airflow reversal at the outlet.

A fan and air conditioner design with improved airflow and reduced noise compared to conventional designs. The fan has a two-section volute tongue that steps in height. The first section extends along the air duct opening and the second section extends from the end of the first section. This smooths the airflow transition and reduces vortex formation compared to a single tongue. The air conditioner has a matching stepped volute tongue in the duct cover and seat. This joint configuration improves airflow in the duct and reduces noise compared to conventional ducts.

Cross-flow wind wheel for air conditioner indoor units that reduces noise compared to conventional wind wheels. The wind wheel has sections of sub-impellers connected by a middle section with hollow cavities and sound absorption holes. The cavities and holes reduce noise generated by the wind wheel during operation. The cavities utilize noise produced by the wind wheel and the holes provide fine sound absorption. This improves noise reduction compared to solid sections.

Fan assembly and air conditioner design that improves airflow uniformity, reduces noise, and improves air conditioner performance. The fan assembly has a volute with a tongue that has a flow diffusion portion and a flow-passing portion. The flow-passing portion is higher than the flow diffusion portion. This configuration enables enlarging the flow-passing area and reducing the flow velocity at that position to make overall fan assembly airflow more uniform.

A cross-flow fan blade for air conditioners that reduces airflow separation and loss by stabilizing the airflow passing over the blade. The blade has a rectifying protrusion that extends out from the back of the blade. This protrusion creates a rectification effect on the airflow, preventing radial movement and reducing separation as the blade rotates. The protrusion is shaped like a fish fin and starts at the thickest part of the blade. This stabilizes the airflow as it passes over the blade, reducing separation and loss compared to a smooth back blade.

Fan structure for air conditioners that reduces noise compared to conventional designs. The fan has a volute cover and seat that form communicating inner and outer air channels. The cover has a first tongue extending into the outer channel. The seat has a second tongue against the cover tongue. The first tongue width is 1/2 to 8/9 the cover width, angle 2-5 degrees, and equal length to the seat tongue. This prevents vortexes and noise compared to spiral volutes. The seat width is 1/9 to 1/2 the cover width. The first and second air outlet sections have equal horizontal length. The first volute tongue width is the duct width, larger than the seat tongue. This configuration prevents vortices and reduces noise compared to spiral volutes.

Fresh air module for air conditioners that reduces noise compared to conventional modules. The module has a housing with an inlet and outlet, a fan assembly with a motor and wind wheel, and a partition between the motor and fresh air duct. The motor is outside the duct in a separate compartment. This isolates the motor noise from the airflow, preventing amplification and reducing overall noise.

Reducing noise from air conditioner fan blades by controlling airflow. The noise reduction structure for an air outlet device of an air conditioner includes fan blades and a heat exchanger. The heat exchanger has gaps between adjacent components. Instead of having small gaps, the gaps are made larger. This reduces the airflow velocity through the gaps compared to smaller gaps. The slower airflow exiting the gaps impacts the fan blades at a lower velocity, decreasing blade noise.

Air conditioner indoor unit with improved blade design to reduce vibration and noise. The indoor unit has a rotatable blade at the outlet to control airflow. The blade is connected to a motor that generates rotational force. The blade also has a material with restoring force. A buffer member connects the blade and transmission to balance the blade when the unit is not perfectly level. This prevents blade vibration and noise when rotating.

Air conditioning unit with reduced noise from fan blades passing and lid fasteners. The unit has an air inlet, fan, control box with lid, and flange to fasten the lid. A flow straightening part covers the flange to smooth airflow around it and prevent turbulence that causes blade passing noise. This reduces the unpleasant NZ sound generated by the fan blades passing the flange area.

Fan assembly for an air conditioner that reduces external noise without adding sound insulation layers or extra components. The fan assembly has a two-stage fan configuration with a fan blade at the inlet and another fan blade in the duct near the outlet. The blade at the inlet has a shallower camber (less curved) at the leading edge than the blade further in the duct. This accelerates and pressurizes the airflow as it passes through, increasing exhaust capacity without adding devices like mufflers or sound insulation.

A reversible axial fan for decentralized ventilation systems that reduces noise and improves pressure stability compared to conventional axial fans. The fan blades have a sinusoidal shape with specific curvature and angle extension on both leading and trailing edges. This profiling reduces tonal noise compared to conventional flat blades while maintaining good airflow. The sinusoidal shape also improves pressure stability compared to conventional fans, especially at low speeds.

Fan device and air conditioning outdoor unit that reduces noise and improves airflow performance compared to conventional designs. The fan has two axially arranged wheels with supports at least on their sides or between them, instead of a bracket that can affect airflow. This avoids interference between the wheels and allows optimal flow. The wheels have equal or greater distances between opposite sides. The outlet side is enclosed and farther from the wheels than a threshold. This prevents vortices and noise. A tapered sleeve surrounds the wheels and connects to the housing. The sleeve has equal sections and gradually decreasing sections.

Volute tongue for air conditioner indoor units that reduces noise compared to conventional designs. The volute tongue has a unique air guiding surface shape with specific radius ratios for three curved sections. The ratios are 40-50:14-17:85-92. This shape improves airflow uniformity and reduces surging, leading to lower noise when the air conditioner is operating.

Reducing air conditioner noise by dynamically adjusting the shape of the volute component near the fan blades. The volute component has a sawtooth piece that can move relative to the main body. When the sawtooth piece overlaps the main body, the volute has a smooth surface. When staggered, it has sawtooth teeth. The sawtooth piece is driven by a transmission assembly to convert between smooth and sawtooth shapes. This allows optimizing the volute shape for different airflow conditions to reduce noise. Additionally, a moving assembly adjusts the volute-fan distance.

Reducing noise in air conditioners by distributing airflow more evenly over the heat exchanger. It involves using a fan with an adjustable air guide that can split the airflow into two sections. One section blows directly out the fan, while the other section is angled to cover a wider area of the heat exchanger. By adjusting the guide position, the fan can blow air more evenly over the heat exchanger surfaces, reducing concentration and fin noise.