GASMAN is a complete model of your gas production system from the reservoir to export pipeline discharge, and is therefore used to analyse the performance of your system as a whole.
The effects of reservoir depletion, well fouling, changing ambient conditions, degradation of compressor performance, etc, on the whole system can be determined for any given operating scenario.
The program can be run in either interactive mode or batch mode. In interactive mode, you can select key parameters such as flows, temperatures and component degradations which the GASMAN system then uses to evaluate system performance. In batch mode, you specify changes in parameters over a period of time and GASMAN then analyses your system's performance throughout that period.
Interactive (Single Step) Runs
Interactive runs are used for production forecasting and optimisation. Either flow or pressure at the platform inlet can be specified together with platform discharge pressure.
GASMAN is then used for production forecasting, or to determine your equipment's design limits. It also optimises gas production. This is determined by adjusting flows to the maximum possible value and discharge pressures such that none of the key items of your equipment (i.e. gas turbines/compressors) operate beyond their design limits.
Batch Mode - Time Stepping
GASMAN simulates the actual operation of your gas field using time stepping. It can be operated at specified time intervals to determine the reservoir and surface facilities over a given time period. The software determines production rates and adjusts gas "in place" and dynamically adjusts the reservoir pressure, well performance, etc. This facility enables the examination of the impact of reservoir pressure decline on compressor performance to be carried out in real time.
This mode is selected to examine the impact of changing certain parameters (e.g. a set of contract flow nominations) over a period of time on the performance of the entire production system.
In a batch run, you may alter the following parameters at each time interval:
Compression platform inlet flow
Number of wells producing
Well fouling
Compressor fouling
Compressor efficiency degradation
Flow by output (contract nomination)
Ambient pressure
Ambient air temperature
Ambient sea temperature
In addition, you may review the effect of production on the depletion of the wells.
Reservoir depletion is calculated and new IPR curves are generated automatically based on the gas produced from the tank; hence the flow and pressure of each contributing well is determined. Arrival pressure at the platform and at compressor inlet is established.
Compressor and gas turbine performance are determined. The effect of varying ambient conditions can be analysed with the batch facility.
GASMAN's batch mode time stepping facility is the most powerful one available for your production forecasting.
Solvers
This functionality enables you to run the integrated GASMAN model to a specific user-defined rule by adjusting other variable/s until this rule is achieved or closest to being achieved.
For example, the model might be set to "always run to the maximum turbine power for all conditions except when limited by the performance of other modules".
Solvers may be used in interactive runs or batch runs and are quite useful when you are carrying out production or maximum deliverability forecasting.
For further information on how GASMAN can help optimise your gas production, please call +44 (0)20 8773 4500 or info@mse.co.uk.
GASMAN Screen Shot
Gasman screen: GASMAN Main Screen