No.55, 4th Binhai Road, Qianwan New Area, Ningbo, Zhejiang
+86 574-63302029
In today's pursuit of a high-quality lifestyle, the ope […]
In today's pursuit of a high-quality lifestyle, the operating noise level of chest freezers has become a key performance metric for both home and commercial users. Low noise not only enhances the user experience but also serves as a crucial indicator of the design sophistication and technological maturity of refrigeration equipment. The operating noise of chest freezers stems from not a single source but rather the combined acoustic energy of multiple core components.
1. Core Noise Source: Compressor
The compressor is the heart of a chest freezer and its primary and most concentrated noise source. Noise primarily arises from three sources:
Mechanical Vibration Noise: When the compressor operates at high speed, internal mechanical components such as the piston, connecting rod, and cylinder generate periodic, high-speed friction and impact. This structure-borne noise is transmitted through the compressor casing and baseplate to the entire freezer enclosure, converting into low-frequency, structure-borne noise. To minimize this noise, professional manufacturers employ optimized balancing designs to ensure the dynamic balance of moving parts. Highly elastic shock-absorbing pads (usually rubber or springs) are used to isolate the compressor from the freezer base, effectively blocking the vibration transmission path.
Gas Pulsation Noise: When a compressor operates, it draws in and out refrigerant gas at high speed, generating periodic gas pressure pulsations. This pulsation propagates through the refrigeration piping, particularly near the exhaust port, creating airflow noise. High-quality compressor designs incorporate mufflers or optimized valve structures to smooth out airflow fluctuations, thereby reducing high-frequency hissing or pulsating sounds.
Electromagnetic Noise: When energized, the motor windings inside the compressor are subjected to alternating magnetic fields, causing tiny vibrations in the stator and rotor. This electromagnetic vibration often produces a continuous humming noise. Compressors using inverter technology can effectively reduce this type of noise by more smoothly controlling the motor speed and avoiding resonance at specific frequencies.
2. Airflow and Heat Dissipation Noise: Condenser Fan
While many small chest freezers use natural cooling, large-capacity or high-performance commercial freezers often require a condenser fan to accelerate heat dissipation from the condenser.
Fan Blade Noise: When fan blades rotate at high speed, they cut through the air, generating vortex and turbulence noise. The intensity of this noise is closely related to the fan speed, blade shape, and number of blades. Using biomimetic blade designs (such as serrated edges) and optimizing the air duct structure can significantly reduce the whistling and wind-shearing noises produced during fan operation.
Fan Motor Noise: Bearing friction or poor dynamic balance in the fan motor itself can also cause noise. Using a high-quality brushless DC motor (BLDC) not only improves energy efficiency, but also produces significantly less friction and electromagnetic noise than traditional AC motors.
3. System Dynamic Noise: Refrigerant Flow and Expansion
During the refrigerant circulation process, some dynamic or occasional noise is generated inside the refrigerator.
Flow and Throttling Noise: When refrigerant flows at high speed in the pipes, especially when throttling and reducing pressure through capillary tubes or expansion valves, it produces a noticeable "hissing" or "liquid-flowing" sound. While this sound is typically brief and subtle, it can become noticeable at specific times, such as during startup. Optimizing pipe diameter and bend angles can reduce fluid resistance, thereby reducing flow noise.
Thermal Expansion and Contraction Noise: The freezer liner and piping expand and contract during rapid temperature changes (especially during compressor shutdown and startup). This can cause subtle "crackling" or "clicking" sounds between the materials. Using elastic gaskets and optimizing the connection structure between the liner and the outer shell can absorb or buffer the noise caused by these stress changes.
4. Structural and Sound Insulation Design: Cabinet Resonance and Sound Insulation Materials
Improper cabinet design of a chest freezer can amplify internal noise.
Cabinet Resonance: If the cabinet's structural rigidity is insufficient or the natural frequency of certain components is close to the compressor's operating frequency, resonance can occur, amplifying low-frequency noise. Using thick, sturdy steel plates and internal reinforcement ribs is key to preventing resonance.
Application of sound insulation materials: Using professional sound insulation materials (Acoustic Insulation Materials), such as sound-absorbing cotton or damping materials, around the compressor cavity can effectively absorb and isolate the high-frequency and medium-frequency noise generated by the compressor and fan, preventing it from leaking into the external environment.