Gasoline generators fully utilize various gases or harmful gases as fuel, turning waste into treasure, with safe and convenient operation, high cost-effectiveness, low emissions, and the advantages of heat and power co-generation, presenting a vast market prospect.

China boasts abundant natural gas resources. Compared to the country's vast natural gas reserves, the proportion of natural gas in China's primary energy consumption is relatively small, indicating significant potential for substantial growth in the future.

In China, due to the influence of gas supply, gas power generation is still in its initial stage. Large-scale gas power generation as distributed energy stations is yet to come. Small-scale gas power generation is mainly found in oil fields, gas fields, as well as airports, hotels, and other locations. It is expected that with the increasingly abundant gas supply and the expanding supply range, gas power generation will see a rapid development in the coming years.

Advantages:

The gas-powered generator set boasts a wide range of output power, high reliability in startup and operation, excellent power generation quality, lightweight, compact size, simple maintenance, and low frequency noise. Generally, it has the following four advantages:

Good power generation quality

Due to the generator set's rotation-only operation, the electronic control responds quickly, ensuring exceptional stability. The generator's output voltage and frequency are highly precise with minimal fluctuations. During sudden 50% and 75% load changes, the set operates extremely stably, outperforming the electrical performance indicators of diesel generator sets.

Section 2: Excellent start-up performance, high start-up success rate

The time from cold start to full load is only 30 seconds, whereas international regulations stipulate that a diesel generator must be loaded within 3 minutes of successful start-up. The gas turbine generator set ensures a high startup success rate in any environmental temperature and climate.

Low noise and minimal vibration

Due to the high-speed rotation of the gas turbine, its vibration is extremely low, and its low-frequency noise is superior to that of diesel generators.

Four, the flammable gas used is a clean and inexpensive energy source.

Such as natural gas, Platycodon gas, etc., power generation sets fueled by them are not only reliable and cost-effective but also turn waste into treasure, without causing pollution.

Noise Control:

The gas power generation set consists of components such as a gas engine, generator, and control cabinet, all mounted on a single steel chassis. The set runs on combustible gases like natural gas, associated gas from oil wells, coal mine methane, water gas, refining off-gases, coke oven gas, and blast furnace gas, offering quick startup and good economy. Particularly due to the demand for high-quality urban living, gas power generation sets are widely used as backup power sources in telecommunications, post offices, banks, libraries, hotels, and other departments. Early gas power generation sets were designed for mine conditions, and the noise produced during operation is typically 95~110 dB(A). The GB 3096-93 urban area environmental noise standard strictly regulates noise levels in urban areas, with 60 dB(A) during the day and 50 dB(A) at night for Class 2 areas (residential, commercial, and industrial mixed zones), and 55 dB(A) during the day and 45 dB(A) at night for Class 1 areas (residential and cultural and educational agency zones). The noise generated by the set during operation causes severe noise pollution in urban environments, affecting people's normal work and life, and limiting the widespread application of gas power generation sets. This article proposes a set of rectification measures to address the noise pollution issue of gas power generation sets, aiming to reduce the noise level and promote the wider use of these sets.

1. Source Analysis

Gasoline engine noise is the primary source of noise in a gas power generation set. Gasoline engine noise can be categorized into aerodynamic noise, combustion noise, mechanical noise, exhaust noise, and vibration noise. Aerodynamic noise mainly includes air vibration noise caused by intake and exhaust as well as fan rotation, which is directly transmitted into the air. The pressure vibration formed by combustion inside the cylinder, radiating outward through the cylinder head and the body, is called combustion noise; the impact noise produced by the piston hitting the cylinder sleeve, the movement of the valve gear, the injection system, and other moving parts is collectively referred to as mechanical noise. During operation, exhaust gases are rapidly ejected from the exhaust valve, flow through the exhaust manifold into the muffler, and then排出 into the atmosphere through the tailpipe. Exhaust noise is the main noise of the engine, typically about 15 dB(A) higher than the engine's main noise, followed by combustion noise, mechanical noise, fan noise, and intake noise.

2. Refurbished Design

Based on the working principle of gas-powered generator sets, it's challenging to reduce noise at the source, so the focus is mainly on effectively blocking its noise propagation pathways. The core of noise reduction technology is to utilize the natural attenuation of sound waves during transmission to reduce the extent of noise pollution. Specific methods to reduce noise include: sound absorption, sound insulation, and altering the direction of noise propagation. In practical engineering applications, typically only one method is used. This article proposes a new combined noise reduction technology for gas-powered generator sets, employing a combination of the three methods.

(1) Combination muffler

The original muffler primarily relied on resistive noise reduction, consuming high power and failing to achieve satisfactory noise reduction. After careful consideration, a new combined muffler was developed using a three-stage noise reduction technology. The main components of this combined muffler include the spray noise reduction and vibration damping chamber, porous noise reduction housing, sound-absorbing and heat-insulating layer, and sound-absorbing resonance plates. The noise energy from mid-to-low frequency sources is effectively dissipated resistively as the sound source passes through the spray noise reduction and vibration damping chamber of the first stage. The second stage's porous resistive muffler housing eliminates most high-frequency noise, enhancing the muffler's adaptability to high frequencies. It also contains sound-absorbing material to fully absorb and redirect noise, thereby maximizing noise energy consumption. The third stage features a specially designed exhaust pipe with resonance plates, further reducing noise through the vibration of thin plates. Tests have shown that the new muffler outperforms the original in noise reduction level, frequency range of noise reduction (mainly the frequency range of the noise reduction peak), and resistance loss. Additionally, the muffler is appropriately sized, has good structural rigidity, is easy to install, and has the function to suppress regenerative noise. The rear sound-absorbing and noise-insulating layer also has corrosion resistance, effectively overcoming low-temperature dew point corrosion of smoke gases and extending the muffler's service life.

(2) Dual-stage Vibration Damping Pads

Effective methods for controlling mechanical and combustion noise involve vibration isolation of the unit. Composite vibration-damping pads are installed between the gas engine, generator, and steel chassis, and high-efficiency vibration-damping rubber pads are also placed between the chassis and the foundation. After two-stage vibration isolation, not only is the vibration of the unit effectively isolated, but the unit's operation becomes more stable, and the overall noise is significantly reduced.

(3) Soundproof Exhaust Duct

Fan noise is composed of rotational noise and vortex noise. Rotational noise is caused by the periodic disturbances generated by the rotating fan blades cutting through the airflow. Vortex noise is a series of swirling flows formed by the separation of boundary layers on the rotating blade section, resulting in gas slip or splitting, which radiates an unstable flow noise. The exhaust duct is directly connected to the outside, with a high air velocity, and the noise from the airflow, fan, and mechanical sources is radiated through this channel. To control the noise of the fan and exhaust duct, a silencing exhaust duct has been designed. This silencing exhaust duct is relatively long and consists of wind guiding grooves and exhaust noise reduction chambers. The working principle of the exhaust noise reduction chamber is similar to that of a resistive silencer. The noise reduction effect can be improved by changing the parameters such as the thickness of the sound-absorbing material (changing the sound absorption coefficient of the material), the length and width of the exhaust duct.

(4) Muffler Inlet Duct

The unit operates within a sealed room. Broadly speaking, the intake system includes the unit's air intake channel and the engine's intake system. The air intake channel, like the exhaust channel, is directly connected to the outside, with a high air flow rate. Both the noise from the airflow and the unit's operation are radiated outside through the intake channel. The noise of the engine intake system is formed by pressure fluctuations caused by the periodic opening and closing of the intake valves, typically in the low-frequency range below 500 Hz. Two silencer intake ducts are installed on the walls of the room, serving as the intake for the room and the engine. Due to the negative pressure caused by exhaust, cold air naturally enters the room through the silencer intake ducts, expelling the heat emitted by the unit smoothly. This ensures there is sufficient fresh air inside the room.