Search results
Results from the WOW.Com Content Network
The former makes the IP compressor surge line shallower, swinging it away from the shallow working line, thus improving IP compressor surge margin. At a given IP compressor pressure ratio, opening the blow-off valve forces the IP compressor entry corrected flow to increase, to a point where the IP compressor surge margin tends to be better.
Compressor characteristic is a mathematical curve that shows the behaviour of a fluid going through a dynamic compressor.It shows changes in fluid pressure, temperature, entropy, flow rate etc.) with the compressor operating at different speeds.
where is the heat capacity ratio / of the gas and where is the total (stagnation) upstream pressure. For air with a heat capacity ratio =, then =; other gases have in the range 1.09 (e.g. butane) to 1.67 (monatomic gases), so the critical pressure ratio varies in the range < / <, which means that, depending on the gas, choked flow usually ...
The compressor pressure ratio is the ratio of the stagnation pressures at the front and rear of the compressor of a gas turbine. Overall pressure ratio in a high-bypass turbofan is a function of inlet pressure ratio and compressor pressure ratio: = The terms compression ratio and pressure ratio are used interchangeably. [1]
Selecting a low efficiency (<60%) is the most common practice used to terminate compressor performance maps at high flows. Another factor that is used to establish the maximum flow line is a pressure ratio near or equal to 1. The 50% speed line may be considered an example of this.
The engine pressure ratio (EPR) is the total pressure ratio across a jet engine, measured as the ratio of the total pressure at the exit of the propelling nozzle divided by the total pressure at the entry to the compressor. [1] Jet engines use either EPR or compressor/fan RPM as an indicator of thrust. [2]
This pressure distribution is simply the pressure at all points around an airfoil. Typically, graphs of these distributions are drawn so that negative numbers are higher on the graph, as the for the upper surface of the airfoil will usually be farther below zero and will hence be the top line on the graph.
A typical stage in a commercial compressor will produce a pressure increase of between 15% and 60% (pressure ratios of 1.15–1.6) at design conditions with a polytropic efficiency in the region of 90–95%. To achieve different pressure ratios, axial compressors are designed with different numbers of stages and rotational speeds.