The VariSim optimiser provides the user with optimised equipment configuration for desired objectives. Common optimisation processes include determination of the lowest fuel usage, fastest delivery routes, maximised storage capacity, timely delivery of batch schedules, optimised heat distribution and minimised DRA usage. Almost any parameter can be optimised. The following are some of the more common optimisation processes which can be combined if required.
This function optimises pumps or compressors within individual or all stations on a pipeline / network. It optimises the pump or compressor configurations so that minimal fuel is used and the most efficient operation is achieved. The user specifies the required operating conditions, the equipment availability and any constraints on the system (such as maximum / minimum allowable pressures). The optimiser rapidly establishes all possible configurations for the pumps / compressors and valve set-points that will achieve the requested operating conditions. It then ranks these possibilities according to the minimal fuel usage.
Heater Optimisation assists the operator in determining the most efficient heater configuration in a station or combinations of stations on a pipeline or network. The user specifies the required operating conditions, the equipment availability and any constraints on the system (such as heater set points and maximum / minimum allowable pressures / temperatures). The optimiser rapidly establishes all possible configurations for the heaters and the heater power requirements that will achieve the requested operating conditions. It then ranks these possibilities according to the minimal fuel usage. Heater optimisation is often installed in conjunction with Pump / Compressor Optimisation. Heater Optimisation is often combined with Pump Optimisation.
The Sump Optimisation function is used within the water industry to optimise pump start and stop cycles. Pumps are frequently set to start and stop at the highest and lowest possible water levels in the sump in the belief that minimising the number of pump starts and stops results in minimised power usage. In certain cases, extending the start and stop levels will improve efficiency of operation but allowing the water level to fall to its minimum level every time the pump starts means that the static head between the sump level and the discharge location is always maximised. The energy required is at its maximum when the water level in the sump is at its minimum. If the stop level is optimised, taking into account the inflow to the sump, and pump operating efficiency, energy usage levels can also be optimised. By connecting the optimiser to the load forcaster, future expected conditions can be taken into account further improving the efficiency of performance.
Throughput Optimisation determines the most efficient route for your product such that it is delivered in the fastest possible time. The optimiser optimises valve states to determine the fastest delivery of product from one location on the pipeline network to another. The user specifies the available valves and the required flowrates and the optimiser outputs a ranked list of valve settings
This function is mainly used for gas applications but can equally apply to liquid. The optimiser is a rapid steady state solver that has the unique ability to consider different initial storage capabilities, valve positions and whether flow is taken from one section of a network or another. In its solution, it can also check that pressure, inventory levels and storage flows are not too high / low meaning that entire – different network considerations can be made. The optimiser provides a series of ranked recommendations (according to the operators requirements) that can be reviewed and used to adjust the operation of the pipeline.
With this optimisation process, nominations, operating conditions and valve positions are allowed to vary with time but all other equipment (compressors etc.) are set to operate at unchangeable speeds. The optimiser will then calculate a very rapid sequence of steady states using a range of valve positions for the current position in the nomination process. This process is ideal for optimising valve routings and for producing optimised storage timeseries
The Batch Scheduling Optimisation process allows the operator to specify the intended future delivery of batches to customers and the batch optimiser will define the best possible batch schedule to achieve these requirements. The user must define (or obtain from an alternative source) the demand flowrate, the supply flowrate and the volumes within supply and terminal tanks to allow the optimiser to determine the batch schedule. Batch Schedule Optimisation is often combined with Pump Optimisation