How Using GT-Power in CFD Can Benefit the Automation Industry

This is part three of a three-part series about the simulation software - GT-Power, and its use in CFD simulations. The first part of the blog series that talks about the introduction about GT-Power. The second part of the series which talks about GT-Power can be used in CFD simulations, you can read it here.  GT-Power is advantageous in the domain of CFD for the automotive industry. Using GT-Power is economically viable, time-saving, and more efficient as compared to physically testing engine components.

Let's delve into some of the useful applications of GT-Power across the automation industry:

Applications of GT-Power in the Emission Control Strategy

One of the most crucial applications of GT Power in the industry is found in the Emission Control Strategy. 

When the automotive industry was about to undergo the transition from Bharat Stage-4 (BS-4) to Bharat Stage-6 (BS-6) model, the most debatable question that arose was whether the implementation of only the 'In-cylinder technology' would be enough to achieve the target emission norms. 

But, with the onset of BS-6, it became clear that 'In-cylinder technology' and 'After Treatment Technology' must go hand in hand to achieve the aim of 'zero emissions.'

Let's look at a quick rundown of these technologies:

In-Cylinder Technology:

• Bowl/injection strategy
• Exhaust Gas Recirculation (EGR)
• Downsizing/Downspeeding
• Component design optimization

After Treatment Technology:

• 3-way Catalytic Converter
• Selective Catalytic Reduction (SCR)
• Diesel Particulate Filters (DPF)
• Diesel Oxidation Catalyst (DOC)

The 'After Treatment' is quite challenging for the manufacturers because the use of precious metals is involved in the process. The addition of even a gram of the metal can make the operation costlier. Thus, they can't think of performing physical testing of components.

If we consider the case of 'After Treatment' modeling using GT-Power, the modeling of various components like SCR, DOC, and DPF can be carried out. The software makes it easy to analyze all the obtained data. 

Modeling the entire layout using GT-Power can reduce the overall project cost immensely and makes engine calibration easier, precise, and accurate. Moreover, by analysis of the data, the amount of conversion taking place could also be obtained, thereby allowing engine optimization without the need for a physical prototype.

Engine Calibration Using GT-Power

Calibration is nothing but figuring out the best-optimized map to achieve the desired performance and emissions. Previously, it was carried out on a proto engine in a physical test-bed.

If we talk about the Engine Operating Point, it is obtained by plotting a curve between torque and engine speed. So, at each point on the curve, the target is to achieve the desired amount of fuel consumed so that both the values, the Brake-Specific Fuel Consumption (BSFC) and Nox emissions are minimized. 

While calibrating the engine, some constraints must be taken into consideration. For instance, the in-cylinder pressure shouldn't be more than 100-200 bar, and exhaust temperature shouldn't go above 700-degree centigrade. The parameters involved are Rail Pressure, the starting and duration of injection, pilot and EGR quantity, etc. 

At each point, the GT-Power Mathematical model can be implemented to obtain the parameter values. These values can be utilized as the input for the Engine Control Unit (ECU) in the tool for engine calibration.

Engine Calibration Using GT-Power in HiL Environment

The next level of engine calibration using GT-Power is the Hardware-in-Loop (HiL), where the Engine Controlling Unit (ECU) and management system is directly in the loop with the model. 

The HiL is basically a virtual engine with which the ECU maintains a continuous relation by forming a loop. The ECU exchanges the data with the virtual engine (HiL), thus making the engine calibration much easier and possible without a physical test-bed.  

Here are some notable features of using GT-Power in the HiL environment:

• You can rapidly convert detailed GT-Power models to real-time capable simulations.
• You can incorporate GT-Power based engine models directly into the control system development process.
• It offers a physically conservative formulation for accurate results.
• It supports HiL and SiL, including systems from ETAS, dSpace, Mathworks, and more.
• The real-time plant model can be integrated into ECU on Hardware-in-loop.

Hybrid Vehicle Modeling Using GT-Power

In a hybrid vehicle, the most crucial aspect of performance is the selection of whether the IC engine needs to be switched on, or if relying on battery power will solve the purpose. Since there are plenty of configurations involved in a hybrid setup, using GT-Power for modeling is quite suitable. 

The key benefit is that it allows you to study and perform analysis of distinct components, starting from the battery management system, integrated electronics, powertrain components, thermal systems to supervisory controllers in one go. 

Here are the features of GT-Power that make it useful for hybrid vehicle modeling:

• Enables you to build any hybrid configuration with any level of electrification, including battery electric vehicles (BEV), plug-in hybrids (PHEV), strong power-split hybrid (HEV), etc.
• Build controls using a comprehensive controls library.
• Advanced capabilities for real-world driving emissions testing, including a random RDE cycle generator.

How is Engine Modeling Done in GT-Power?

GT-Power is well-equipped with tutorials and examples concerned with engine modeling applications. Moreover, the documentation offered by the software is up to the mark. 

While starting the analysis, you can quickly refer to the innumerable tutorials available such as the air conditioning system, after treatment, engine performance, lubrication, transmission, and much more.

After putting the values concerning the corresponding engine components, a mathematical model is set up, and the algorithm of the software starts solving the Navier-Stokes equations in the background. Once the results are ready, you can analyze them by collecting the data from the report tables in the results file. 

Conclusion

Using simulation tools such as GT-Power, we can prepare the mathematical model of the layout to be analyzed. Therefore, there is no need for a prototype to test different layouts and engine systems. 

What's important to note about GT-Power is that it is just a mathematical tool which is capable of solving and processing the data input. So, engineers who want to make the most out of this software must possess engineering expertise and knowledge. 

Learn more about GT-Power by enrolling for the GT-Power course at Skill-Lync. Our expert instructors equip you with the theoretical knowledge as well as practical skills for a promising career in fluid dynamics.