How Does High Altitude Affect The Performance Of Air Compressors?

How does the air compressor system work?
Most mobile air compressor systems are powered by diesel engines. When you turn on this engine, the air compression system sucks in ambient air through the compressor inlet, and then compresses the air into a smaller volume. The compression process forces the air molecules closer together, increasing their pressure. This compressed air can be stored in storage tanks or directly power your tools and equipment.
As the altitude increases, the atmospheric pressure decreases. Atmospheric pressure is caused by the weight of all air molecules above you, which compress the air around you downward. At higher altitudes, there is less air above you and therefore lighter weight, which results in lower atmospheric pressure.
What effect does this have on the performance of the air compressor?
At higher altitudes, lower atmospheric pressure means that air molecules are less tightly packed and less dense. When an air compressor sucks in air as part of its intake process, it sucks in a fixed volume of air. If the air density is low, there are fewer air molecules sucked into the compressor. This makes the volume of compressed air smaller, and less air is delivered to the receiving tank and tools during each compression cycle.

Relationship between atmospheric pressure and altitude
Engine power reduction
Another factor to consider is the effect of altitude and air density on the operation of the engine driving the compressor.
As altitude increases, the air density decreases, which results in a roughly proportional decrease in the horsepower your engine is able to produce. For example, a normally aspirated diesel engine might have 5% less power available at 2500 m/30℃ and 18% at 4000 m/30℃, when compared to operation at 2000m/30℃.
Reduced engine power can result in a situation where the engine bogs down and the RPM drops which results in fewer compression cycles per minute and therefore less compressed air output. In extreme cases, the engine may not run the compressor at all and will stall.
Different engines have different de-rate curves depending on the design of the engine, and some turbocharged engines can compensate for the effect of altitude.
If you are working or plan to work at a higher altitude, it is recommended to consult your specific air compressor manufacturer to determine the impact of altitude on your air compressor.

De-rate curves example of the engine
How to overcome problems related to altitude
There are some ways to potentially overcome the challenges of using air compressors in high altitude areas. In some cases, a simple adjustment of the engine speed(RPM) to increase the speed of the compressor will be all that is needed. Some engine manufacturers may also have high-altitude components or programming to help offset power drops.
Using a higher output engine and compressor system with enough power and CFM to meet your needs, even if performance declines may be a viable option.
If you have challenges with air compressor performance in high altitude areas, please consult the GTL directly to see what they can provide.

Post time: Aug-25-2021