In order to proceed to performance evaluation,
IPC applied this method in the following steps:
n
Expected performances related to design inlet
conditions have been adjusted to field suction
conditions.
n
Field performances are compared to adjusted
expected performances.
At this point it is possible to proceed with the
comparison.
Software
In order to use Cmap, the starting point is the
availability of a compressor performance map, the
relevant gas mix composition and thermodynamic
conditions (pressure and temperature). Having this
input data available, the software will perform all
complex calculations fully and produce expected
compressor performance details.
The input process offers a number of alternative
methods of entry. The most common method is to
enter performance curves expressed in terms of
delivery pressure versus inlet flow rate, and delivery
temperature versus inlet flow rate. Data input
processes can also be executed in a digital way,
picking up graphical data directly from pdf or jpeg
files.
Cmap is structured to allow analysts and
engineers to build their own machinery database and
maintain the records of all executed calculations.
Case study
The compressor under study was mapped for two
different inlet conditions of pressure and
temperature:
Design condition 1 (D1)
Pressure: 40.2 bar.
Temperature: 50 ˚C.
Design condition 2 (D2)
Pressure: 53.2 bar.
Temperature: 37.8 ˚C.
Starting from the curves of the D1 condition, the
expected performance curves in the D2 were
calculated using the Cmap software. The obtained
curves, D2calc, were then compared to the D2 curves
available as input.
Figure 3 compares the D2calc with the D2
performance curves. The curves almost overlap: the
maximum error calculated is less than 0.2%
(polytropic work at maximum speed). Measured
errors have been considered tolerable for the
purpose of the evaluation of compressor field
performance.
This case study confirms the capability of the
proposed method to predict compressor
performances aligned with design ones. An important
application of these proposed methods is on surge
protection systems and for diagnostic purposes.
Sandvik sulphur
solidification solutions
Our acquisition of the technology and know-how of the
Brimrock Group means we now offer a full range of
solidification solutions, from our proven Rotoform
pastillation process and Brimrock RS1500™ granulation
to complete block pouring and forming facilities. No
wonder we’re known as The Sulphur Company.
n
Rotoform granulation for premium quality
and small/mid-size capacity
n
Fully automated Brimrock RS1500™
for fast, reliable high capacity granulation
n
Block pouring for cost effective long term storage
n
End-to-end process capability – from receipt of liquid
sulphur to storage, handling and loading
It’s what we do.
Sandvik Process Systems
Division of Sandvik Materials Technology Deutschland GmbH
Salierstr. 35, 70736 Fellbach, Germany
Tel: +49 711 5105-0 · Fax: +49 711 5105-152 ·
