Muffler Exhaust Manifold Muffler Tips/pipes Muffler Relative How to evaluate the performance of muffler The performance of the muffler can be evaluated on the below three aspects: A. Noise Elimination Performance is the noise reduction and spectrum characteristic of the muffler. Noise reduction of the muffler is generally expressed with sound transmission loss and insertion loss as well as end sound level difference at air outtake (or air intake) in field test. The spectrum characteristic of the muffler is generally expressed with noise reduction of octave band or 1/3 octave band. B. Aerodynamic Performance is resistance loss or resistance coefficient. The resistance loss of the muffler is generally expressed with the full pressure difference between inlet and outlet of the muffler; the resistance coefficient can be worked out with dynamical pressure and resistance loss of the muffler. The aerodynamic performance of the equipment must be affected should the muffler is mounted on the air duct. If only the noise elimination performance of the muffler is concerned with the aerodynamic performance neglected, the efficiency of the equipment might be greatly reduced by the muffler or even the equipment does not work under some circumstances. C. Structure Performance: For the mufflers with the same noise elimination performance and aerodynamic performance, the smaller in geometrical size, the cheaper in price, the longer in service life, the better. Does the airflow have impact on the Muffler? When the airflow passes through the muffler, a new noise is superposed to the original pipe noise and thereby the real use effect of the muffler is affected. This noise is airflow-regenerated noise that is radiated as a result of local resistance force applied to airflow, turbulent flow generated by frictional resistance or vibration of muffler components activated by airflow. The value of the airflow-regenerated noise depends mainly on airflow speed and the structure of the muffler. In general, the higher the airflow speed or the more complicated (such as duct section mutation, bend or obstruction, etc.) the internal structure of the muffler, the bigger the noise generated. Why does the Muffler emit blue smoke in the running of engine? The reason for the above failure is that engine oil joins in combustion. After detecting this failure, check oil rule to see if engine oil is in excess at first. If so, run 10 minutes after draining the redundant engine oil. Inspection and repair of the engine are required if the problem is not solved. Why does the Engine Muffler emit black smoke? The reason for the above failure is higher blend gravity of inlet gas combustion. In case of this situation, clean or replace the air filter at first. If the problem is not solved, please adjust or clean the engine carburetor. Types of Muffler Dissipative muffler, reactive muffler, dissipative and reactive compound muffler, microperforated panel muffler, micropore muffler and active muffler. What is a Muffler? Description: A standard or stainless steel casing containing an array of baffles and other sound-insulating material to reduce exhaust noise. Some cars may use several mufflers, or a secondary muffler called a resonator. Purpose: The muffler reduces and changes engine exhaust sound and tone. When properly matched to the engine, a muffler will not impair engine performance due to exhaust backpressure, which is simply the resistance to exhaust flow. Maintenance Tips/Suggestions: Have your vehicle?s exhaust system inspected periodically to keep your car safe. The muffler may not be individually replaceable due to the condition of other exhaust system components, or because the original exhaust system uses a unitized construction, where sections are welded together. Keep in mind that exhaust gas, especially carbon monoxide, can be deadly if it enters the interior of the car. The symptoms of an exhaust leak may include a louder than normal exhaust sound, the sound of exhaust coming from unusual places on your car, a ?ticking? noise when accelerating, and the smell of exhaust. However, don?t rely on your sense of smell as a conclusive means of determining if there?s an exhaust leak. Carbon monoxide has no odor. If you suspect any problem with the exhaust system, have it inspected immediately by a professional technician. Another symptom of a potential exhaust leak is a failed emissions test. A leak not only lets exhaust gas out, it also allows oxygen to enter the exhaust stream, which can be detected during an emissions test. You will usually be required to make repairs before retesting, so have the leak checked by a professional technician. A muffler is a unit that is mounted on the air duct or in the air intake/outtake system of aerodynamic equipment (e.g. air blower and air compressor) to reduce noise. Muffler is an effective tool to control noise since it can block the spread of sound wave and allow the airflow to pass through.