Automotive Turbocharger

Turbocharged Internal Combustion (IC) Engine Model

Open the waste gate too slowly, or inject gases from an EGR too quickly, and the compressor will surge, overloading the intercooler with warmer air without a corresponding increase in pressure (not to mention noise).  Open the waste gate too quickly, or fail to get exhaust gases to the turbine fast enough, and the boost lags and the compressor might even choke when it fails to meet a sudden engine demand.

And those are just some of the transient interactions between the turbocharger and the engine. Before you can get to that point, you have to first design a compressor, turbine, and intercooler that are well matched to the engine over a wide range of operating conditions, probably assuming perfect or instantaneous controls as a starting point.

Two sample FloCAD models were built to explore both

  • short time-scale events such as pressure waves within intake and exhaust runners (Detailed-level, applicable for valve or control system stability investigations), and
  • long time-scale events such as boost lag (System-level, including steady-state solutions for rapid sizing).

These models illustrate key program features and capabilities, but they may also be used as templates for other engine and compressor/turbine design studies.

A library of six turbine and five compressor designs was constructed as part of these models, and the development of those turbomachine designs is also summarized.

Click here to download this sample from our support forum

The development of this sample model spawned of another IC Engine sample model designed to explore fast‐transient interactions within an engine.

 

Chart of Turbocharger Shaft Speed Lagging a Transient Engine Acceleration

Turbocharger Shaft Speed Lagging a Transient Engine Acceleration

 

Chart of Waste-gate and Pop-off Valve Responses to the Engine Acceleration Event

Waste-gate and Pop-off Valve Responses to the Engine Acceleration Event

 

Parametric Sweeps of Net Torque on Turbocharger Shaft to Find Steady Operating Points

Parametric Sweeps of Net Torque on Turbocharger Shaft to Find Steady Operating Points.

 

Postprocessed Sinaps® Diagram showing Temperatures and Flows for Detailed Model

Postprocessed 2D-sketch Mode FloCAD® Diagram showing Temperatures and Flows for Detailed Model

 

Chart of Pressures in the Intake and Exhaust Systems During One cam shaft Revolution

Pressures in the Intake and Exhaust Systems (for Cylinder #1, 3000 rpm) During One cam shaft Revolution (TDC at left, center, and right of plot)

 

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