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

 

flow regimes

Introduction to Two-phase Flow

September 24, 2-3pm MDT

This webinar introduces basic concepts in two-phase flow modeling including quality, void fraction, flow regimes, slip flow, pressure drops and accelerations, and heat transfer.

No knowledge of CRTech software is required. However, references to the corresponding FloCAD features will be made to assist users of that product.

Click here to register

Introductory FloCAD Training

Class times: September 5, 10, and 12, 2019, 9:00 am to 12:00 pm MDT daily
Cost: no charge (attendees must have an active support contract)

CRTech will be hosting introductory training for FloCAD (Flow Modeling in Thermal Desktop). This is our standard FloCAD class previously hosted in a classroom environment and now restructured for an online teaching environment.

The class will introduce single-phase fluid modeling concepts and how to build fluid models within the FloCAD work environment. Topics covered include an introduction to fluid modeling components, geometric versus non-geometric modeling options, working with FloCAD Pipes, solution control, and an introduction to path and pipe libraries.

The class will be broken into three two- to three-hour sessions held over a 3 day period. The format will be online lecture and demonstration with opportunities to ask questions. Hands-on lab work will be provided to students to work on after each session. To gain the most from this class, students are encouraged to attend all three sessions.

Prerequisites: Attendees must have basic working knowledge of Thermal Desktop as many of its base features will not be covered in this class but their usage is required for FloCAD.

Eligibility Requirement: This class is a service to our customers. All attendees must have an active support contract. If you are unsure of your support status, please contact CRTech.

Click here to register