Computational Engineering & Modelling

Digital Twin Modelling

Design of model-based digital representations of physical assets that are updated from data, including the choice of fidelity, data flow and the decisions the twin is meant to support.

Last updated:

  • DivisionComputational Engineering & Modelling
  • Scope items5 defined
  • Typical inputs3 to share
  • Agreed deliverables3 outputs

Service overview

Mathematical modelling, numerical methods, multiphysics, uncertainty analysis and digital twins. This service is part of that division and is scoped individually around what you need to learn, decide or publish.

A digital twin is a model that stays synchronised with a physical asset by being updated with data from it. The phrase is used loosely, and many so-called twins are simulations with a dashboard. A useful twin is defined by its purpose: the decisions it will inform, the quantities it must estimate, the fidelity required and the data that keep it current.

The design questions are therefore practical. Which states of the asset matter and which can be measured? How often must the model be updated, and how quickly must it run? How will model error and sensor error be separated? How will the twin be validated against operating data and its trust monitored over time? This service helps answer those questions and structure the modelling accordingly.

If you plan to publish the outcome, see manuscript & publication support, for example computational & simulation manuscripts or original research article writing.

What this service covers

Problems this service can address

  • Confusing a static simulation model with a continuously updated twin
  • Sensor data too sparse or noisy to update the model
  • No defined decision that the twin will inform

Methods and analytical approaches

  • Twin purpose and fidelity definition
  • State estimation and data-assimilation concepts
  • Reduced-order models for fast updates
  • Validation against operating data

Applications

  • Condition monitoring of machinery
  • Infrastructure health monitoring
  • Process monitoring and what-if analysis

Scope, inputs and deliverables

Scope of work

  • Definition of the physics, geometry and quantities of interest
  • Model set-up with verification and, where data allow, validation
  • Parametric or sensitivity studies agreed at scoping
  • Results and documentation suitable for reports or publication
  • Feasibility check on: description of the physical asset and its sensors

Typical inputs required from you

  • Description of the physical asset and its sensors
  • Available historical data
  • Decisions the twin should support

Deliverables

  • Twin architecture and data-flow description
  • Prototype model and validation results where data allow
  • Roadmap and limitations

Highly specialised requests are first checked for feasibility from this information. Please do not send confidential data through the public form; describe it first and agree secure transfer afterwards.

Project workflow and method

  1. 01Enquiry and requirement assessment
  2. 02Technical scoping and proposal
  3. 03Execution
  4. 04Quality review and delivery, with an agreed round of revisions

Read the full project workflow.

In depth: how the work is done

  1. Defining purpose and fidelity

    We begin with the decision the twin supports, for instance scheduling maintenance, detecting abnormal behaviour or exploring operating alternatives. The decision determines the required quantities, accuracy, update frequency and latency. Fidelity is chosen to be sufficient, not maximal: a simple physics-based or data-driven model that runs in real time may serve better than a detailed model that cannot be updated. The requirements are written down and used later to judge whether the twin is fit for purpose.

  2. State estimation and data assimilation

    Sensors provide partial and noisy measurements, while the model describes how states evolve. State estimation techniques, from Kalman-type filters for linear or mildly nonlinear systems to particle and ensemble methods for strongly nonlinear ones, combine the two to estimate states and, when needed, parameters. Observability analysis checks whether the available sensors make the quantities of interest estimable at all. Sensor faults and communication gaps are anticipated in the design.

  3. Reduced-order and hybrid models

    High-fidelity simulations are rarely fast enough for continuous updating. Reduced-order models derived from simulations or data capture dominant behaviour at low cost. Hybrid approaches combine physics-based models with data-driven corrections that learn residual discrepancies. Each approach has a domain of validity, and the twin should monitor whether operating conditions have drifted outside it. We help select and validate the approximations in light of the required accuracy.

  4. Validation, drift and lifecycle

    A twin is validated by comparing its estimates with independent measurements across the range of operating conditions, including unusual ones. Over time, asset wear, repairs and changes in operation can make the model drift from reality, so monitoring of residuals and re-calibration procedures are part of the design. Governance matters too: version control for models and data, records of assumptions and clear statements about who may act on twin outputs and under what conditions.

  5. Governance, data and ethics

    Digital twins depend on continuous data, which raises questions of ownership, security and access. We recommend documenting who owns the data and models, how access is controlled, how sensor data are validated and how the twin's outputs are to be used in decisions. For safety-relevant applications, clear boundaries on the use of twin outputs and a human-in-the-loop requirement are advisable. These considerations are best settled early, because they affect architecture as well as policy.

Quality control and good practice

Quality-control approach

  • Verification: mesh, time-step and solver sensitivity are examined before results are reported.
  • Validation: results are compared with measurements or reference solutions where these exist, and the absence of such data is stated.
  • Boundary conditions and material or fluid properties are recorded with their sources.
  • Sensitivity to the least certain inputs is shown or explained.

Common pitfalls this service helps avoid

  • Starting with technology, not purpose. A twin without a decision to support accumulates data and cost without value.
  • Unobservable states. If sensors cannot reveal the quantity of interest, no estimator can recover it reliably.
  • Ignoring model drift. As assets change, a once-accurate model can quietly become misleading.
  • Overstating autonomy. Twin outputs are estimates with uncertainty and should support, not replace, engineering judgement.

What good reporting looks like

A digital-twin design report states the purpose and requirements, system description, available data and sensors, modelling approach, estimation method with observability analysis, validation against operating data, performance measures, monitoring and update strategy and limitations. It describes data flows and assumptions in enough detail for implementation by an engineering or software team. It does not claim capabilities that have not been validated, and it distinguishes proposed design from demonstrated performance.

An illustrative scenario

Hypothetical example written for explanation. It is not a client case, a result or a testimonial.

Imagine a team that wants a model of a pump station to support maintenance planning. The requirements state that bearing temperature and vibration trends must be tracked hourly. A reduced thermal model is driven by measured flow and ambient temperature, a filter estimates unmeasured heat generation, and the residual between model and sensor flags unusual behaviour. Validation against a year of data shows good tracking in normal operation and poorer performance during start-up transients, which the report records as a limitation.

Questions to settle before you begin

  • What decision will the twin support, and how fast must it respond?
  • Which states matter, and can sensors observe them?
  • How will model and sensor errors be separated?
  • What independent data will validate the twin?
  • How will I detect and correct model drift over time?

Key terms

Digital twin
A model kept synchronised with a physical asset using data.
State estimation
Inferring system states from a model and noisy measurements.
Observability
Whether measurements allow system states to be determined.
Data assimilation
Combining models with observations to update estimates.
Reduced-order model
A simplified model capturing the dominant behaviour at lower cost.

Working together on Computational Engineering & Modelling projects

Computational engagements begin by agreeing the question, the quantities of interest and the accuracy that matters, so that modelling effort goes where it changes the answer. We ask for geometry or system descriptions, operating conditions, material or property data and any measurements for validation. Early on, a small pilot case often checks feasibility and cost. Models are verified and, where data allow, validated before parametric results are produced. Software, versions and settings are recorded so results can be reproduced. Where inputs are missing, assumptions are listed and agreed rather than quietly filled in.

Frequently asked questions

Do you deploy a live twin in my plant?

Our scope is modelling, analysis and documentation, not plant integration or operation of production systems.

Do you build and deploy the software platform?

The service concentrates on modelling, estimation and validation design. Platform integration can be discussed within an agreed scope.

Does a twin need machine learning?

Not necessarily. Physics-based, data-driven and hybrid models are all used, and the best choice depends on purpose, data and required interpretability.

How much operating data do I need?

Enough to estimate parameters and validate across relevant conditions. A feasibility review of your data is part of scoping.

Can a twin predict failures?

It can support predictions of degradation if the models and data support them. Claims are limited to what validation shows.

How is this service scoped and priced?

After your enquiry we review what you need, ask for missing information and send a written scope and quotation. Price depends on complexity, deliverables and timeline. See the project workflow.

Discuss your project: Digital Twin Modelling

Share your objectives, data situation and target outcome. We will assess the scope and suggest sensible next steps.