Process Simulation
for Allocation

Charm logo

Launched in 2016, CHARM (Compact Hydrocarbon Allocation Reference Model) is a fast and cost-effective process simulation software package which models hydrocarbon behaviour specifically for hydrocarbon allocation purposes.

Developed by Accord in collaboration with Robert Gordon University’s Smart Data Technology team via a Knowledge Transfer Partnership, CHARM has been designed as a versatile and practical hydrocarbon modelling software. CHARM performs quick and efficient calculations to determine how hydrocarbons partition into liquids and gas as they pass through a process facility. This allows the determination of factors frequently used in allocation schedules e.g. shrinkage factors. Also, by using a cloned-component approach, it is possible to accurately track hydrocarbons from multiple fields through a combined system.

Using recognised thermodynamic equations of state, CHARM is trusted by operators and integrates readily with existing in-house software and third party products. Deployment options include local installation and hosted web service.

Accord CHARM


Times per day CHARM is called to support a range of North Sea allocation regimes


Seconds required to complete 40 flash calculations in a simulation model


Leading hydrocarbon accounting software platforms can integrate with CHARM

CHARM — At a Glance


Offering the same levels of accuracy as other leading commercial process simulation software, CHARM is an excellent option for hydrocarbon allocation operations of any scale and complexity.

Flexible & Cost Effective

Each call to CHARM contains the configuration of the process being simulated allowing modifications to the model to be easily implemented.

Specialised for Allocation

CHARM is designed to focus purely on the subset of calculations required for hydrocarbon allocation — offering fast, repeatable results that are transparent and auditable.

Practical & Robust

CHARM users can check, develop and maintain their process model without requiring specialist process simulation product knowledge.

Trusted by Operators

For allocation, CHARM is now established as the process simulation package of choice for numerous operators. CHARM has been extensively validated by comparing the results of the calculations to those from other commercial packages for a variety of process networks.

Integration-Ready & Future-Proofed

CHARM was developed to adhere to industry standards, with easily-maintained XML-based interfaces to ensure ongoing compatibility with existing and future hydrocarbon allocation systems.

A Foundation for Further Innovation

Having been in use by a variety of operators for several years, the efficacy of CHARM is well-proven and its potential for further development is clear. The software’s easy-to-integrate design means that it now forms the basis for several research and development projects at Accord — exploring wider functionality and specialised uses — e.g. metering projects and work with non-hydrocarbons.

One recent example of further innovation with CHARM is Accord’s Combustor project, which utilises this process simulation capability to calculate the combustion efficiency of flaring and to find opportunities to reduce the excess methane emissions from inefficient flaring. Learn more on the Combustor page.

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Book a

Interested to see CHARM in action? Contact the Accord team to arrange a demonstration, where we can outline the key features and functionalities of the software in greater detail.

“The provision of relevant industry-standard calculations in a package which can be seamlessly and efficiently integrated into an allocation system, delivers a real-world capability to incorporate process simulations directly into allocation regimes.”

Euain Drysdale

Euain Drysdale