MATLAB and EXCEL Integration

Integrated Analysis Environments for Heat Transfer and Fluid Flow
 

"As technology matures, it disappears."
                                            - M. Weiser, Xerox PARC (paraphrased)

One of our key jobs at CRTech is to make our thermal/fluid solution technologies disappear ... to become components of a custom multidisciplinary design environment.

CRTech provides best-of-class user-extensible heat transfer and fluid flow design and analysis capabilities accessible through both geometric and nongeometric user interfaces. But we realize that some customers’ needs are best served with their own custom environment or interface. We are also strong proponents of system-level trade studies and other high-level design tasks that require the feedback of many specialized analyses and considerations: structural, electrical, CFD, aerothermal, optical, reliability, life cycle cost (LCC) or net present value (NPV), etc.

Therefore, not only are our tools highly extensible and customizable, and not only are they fully parametric and able to respond dynamically to model changes, but we also provide APIs (advanced programmer interfaces) and other tools for integrating SINDA/FLUINT and Thermal Desktop®, RadCAD®, FloCAD® solution technologies into a higher-level design evaluation system. Such capabilities are available for codes such as Microsoft Excel®, Comet Solutions, and Noesis' Optimus®, and we welcome the opportunity to create additional connections.

Download API Brochure

MATLAB® as an Example

Example of NREL Advisor IntegrationTo illustrate the possibilities, the interchange with Mathworks' MATLAB® and Simulink® is briefly described. SINDA/FLUINT can be started as a subprocess of MATLAB on a PC. “Registers” and other data values can be passed back and forth between SINDA/FLUINT and MATLAB, as commanded from either code. SINDA/FLUINT’s execution can be suspended and restarted from MATLAB, which can send signals back to SINDA/FLUINT to perform operations such as redo a steady-state analysis, advance a transient time step, perform an optimization, or everything else that is accessible from within SINDA/FLUINT’s user logic blocks (which is almost everything).

Thermal Desktop’s Dynamic Mode can be used to further expand this system, by calling for new Thermal Desktop or RadCAD geometric (radiative, thermal contact, FEM, FDM, etc.) solutions from within SINDA/FLUINT, perhaps as directed from MATLAB or another program.

Although most such integrations are proprietary, an example of one that is documented publicly is NREL’s ADVISOR used for integrated automobile design.

Relevant Links: MDO and MDA

Additional Resources

Contact CRTech for MATLAB interface examples or see the example on our User Forum.

Contact CRTech for Excel TD Controller.

Publication

Customizable Multidiscipline Environments for Heat Transfer and Fluid Flow Modeling, ICES 2004

dispersed vs. coalesced front

Tuesday, June 26, 2018, 1-2pm PT, 4-5pm ET

This webinar describes flat-front modeling, including where it is useful and how it works. A flat-front assumption is a specialized two-phase flow method that is particularly useful in the priming (filling or re-filling with liquid) of gas-filled or evacuated lines. It also finds use in simulating the gas purging of liquid-filled lines, and in modeling vertical large-diameter piping.

Prerequisites: It is helpful to have a background in two-phase flow, and to have some previous experience with FloCAD Pipes.

Register here for this webinar

FloCAD model of a loop heat pipe

Since a significant portion of LHPs consists of simple tubing, they are more flexible and easier to integrate into thermal structures than their traditional linear cousins: constant conductance and variable conductance heat pipes (CCHPs, VCHPs). LHPs are also less constrained by orientation and able to transport more power. LHPs have been used successfully in many applications, and have become a proven tool for spacecraft thermal control systems.

However, LHPs are not simple, neither in the details of their evaporator and compensation chamber (CC) structures nor in their surprising range of behaviors. Furthermore, there are uncertainties in their performance that must be treated with safety factors and bracketing methods for design verification.

Fortunately, some of the authors of CRTech fluid analysis tools also happened to have been involved in the early days of LHP technology development, so it is no accident that Thermal Desktop ("TD") and FloCAD have the unique capabilities necessary to model LHPs. Some features are useful at a system level analysis (including preliminary design), and others are necessary to achieve a detailed level of simulation (transients, off-design, condenser gradients).

CRTech is offering a four-part webinar series on LHPs and approaches to modeling them. Each webinar is designed to be attended in the order they were presented. While the first webinar presumes little knowledge of LHPs or their analysis, for the last three webinars you are presumed to have a basic knowledge TD/FloCAD two-phase modeling.

Part 1 provides an overview of LHP operation and unique characteristics
Part 2 introduces system-level modeling of LHPs using TD/FloCAD.
Part 3 covers an important aspect of getting the right answers: back-conduction and core state variability.
Part 4 covers detailed modeling of LHPs in TD/FloCAD such that transient operations such as start-up, gravity assist, and thermostatic control can be simulated.