Joule-Thomson (JT) Cooling

Joule-Thomson Design and Analysis

CRTech tools are used to model the complexities of Joule-Thomson or JT cooling systems, as either blow-down systems or closed cycles (e.g, Linde-Hampson). Because they provide compact and vibration-free cold heads, such coolers are popular for cooling of sensors and electronics including cryogenic and MEMS (microcooling) applications.

The combination of SINDA/FLUINT plus FloCAD® (an optional Thermal Desktop® module) can be used for detailed modeling, system-level modeling, and sizing and sensitivity analyses of cold heads and other heat exchangers.

Key features relevant for analyzing JT cooling systems include:

  • Real-gas and saturation dome properties readily available for the most commonly used fluids including hydrogen, helium, nitrogen, argon, CO2, methane, and propane. Additional and custom fluids (e.g., mixed gas coolers) descriptions can be created by CRTech or the user.
  • System-level heat exchangers (e.g., NTU, UAtot, effectiveness) for sizing (e.g., set an outlet temperature) and for high-level simulations
  • Complex heat exchangers in cold heads and in multi-stage coolers (regenerators, recuperators, intercoolers)
  • Transient analyses including tank blow-down and structural cool down
  • Expansion into the dome including two-phase heat exchange. See also Two-phase Flow Analysis.
  • Arbitrarily complex control systems (PID etc.) applied to valves, compressors, etc.
  • Access to parametric modeling and Advanced Design Modules (optimization and sizing, automated model calibration to test data, reliability and statistical design, etc.)

Sample Model of a JT Cold Finger

A sample model is available to illustrate the application of SINDA/FLUINT and Thermal Desktop/FloCAD to the modeling of the Joule-Thomson cycle. These examples demonstrate:

  • JT cryostat analysis
  • Design optimization and dynamic blow-down (chilldown) analysis
  • Modeling of labyrinth seals (even though they purposely leak in this application)
  • Modeling of heat exchangers, at both the system and detailed levels
    • Including application of compact heat exchanger (CHX) methodology
  • Use of FloCAD for both sketch-pad modeling and for geometric modeling

The models with documentation are available for download.

Click here to fetch the JT Modeling Example from our User Forum


Advanced Pipes in FloCAD
Thursday November 14, 9-10am MT (8-9am PT, 11am-noon ET)
This webinar introduces advanced features for FloCAD pipes in addition to working with complex geometry. Complex geometry includes interior fins and surfaces for heat transfer, flow around enclosed objects, annular flow, concentric pipes, and more. FK Locators and TEEs as modeling objects will also be introduced.
Custom Heat Transfer and Pressure Drops
Tuesday November 19, 2-3pm MT (1-2pm PT, 4-5pm ET)
Do you know what the default assumptions are in FloCAD, and whether or not they apply in your situation? Do you know how far you can go past that starting point? The answer: pretty far. There are numerous mechanisms in FloCAD for adjusting factors, scaling uncertainties, and applying different or supplemental correlations. This webinar summarizes the options available to you to customize your flow models to make sure that they apply to each new situation you encounter.
Heat Exchangers: Detailed and System-level
Thursday November 21, 2-3pm MT (1-2pm PT, 4-5pm ET)
This is two webinars in one. The first explains the use and assumptions behind the FloCAD HX system-level modeling object. The second webinar describes detailed-level modeling of complex heat exchanger passages, including application of Compact Heat Exchanger (CHX) methods.
Starting in 2020, we will begin offering Introduction to Thermal Desktop and Introduction to RadCAD as either in-person training or online training, alternating between online and in-person every three months. The training uses lectures and demonstrations to introduce you to basic Thermal Desktop and RadCAD usage. Hands-on tutorials provide practice building models and interpreting results (tutorials are completed by students outside of the online class time).
The next training class will be an online format in January 2020:
  • Introduction to Thermal Desktop (and SINDA) - A three-part series on January 14, 16, and 21 from 9am to 12pm, Mountain time
  • Introduction to RadCAD - January 23 from 9am to 12pm, Mountain time
For up-to-date schedules, fees, and policies, visit our Product Training page. To register for the class above, complete our registration form and select "Online" for the Training Format.
If you are interested in product training for your company based on your schedule, please contact us to obtain a quote for training between 8-12 attendees. We can come to your facility or the lectures can be presented online. Descriptions of the available classes can be found in our course catalog.
To keep up with our training opportunities, take a look at our new Events and Training Calendar.