Ansys and Electro Magnetic Applications (EMA) launch a new design tool to assess charging and discharging.

The Need for Predictive Charging and Discharging Simulation

Ansys and Electro Magnetic Applications (EMA) have announced the release of EMA3D Charge, a charging and discharging simulation tool. The new tool has the same goal that all Ansys products have—to bring simulation into the design and development process in an effort to save time and money.

EMA3D Charge simulates the surface charging of materials. (Image courtesy of Ansys.)

EMA’s flagship product, the EMA3D Cable solver, brings together a finite-difference time-domain (FDTD) solver and a multi-conductor transmission line solver. When the two solvers work together, designers and engineers can take the boundaries of a product or assembly and find optimized cable harness geometry. The EMA3D environment has both a CAD tool and a GUI tool to provide users with options for design and control without requiring them to leave the solution.

EMA3D Cable was born from a previous partnership between Ansys and EMA. One of the original goals of the tool was finding a way to shorten the time that it takes to develop an electronic product by shortening the certification time line. The groups focused on cable harnesses for automotive and aerospace applications. Transmitting power, or signals, through cables must meet a set of regulations, usually governmental, that dictate how the harnesses are protected from electromagnetic interference.

The Dangers of Electric Discharge

Static electricity and the danger of shock or system failure can happen at both small and large scales. At a basic level, static electricity occurs when two objects, of different materials, contact each other and the frictional forces building up a charge. For a person, this might mean getting a small zap to the hand when reaching for a doorknob or hearing crackles when opening the dryer door after running a heavy load.

The Occupational Safety and Health Administration says that charges can build when a worker is handling plastic pipes, or during the operation of rubberized machine belts. These charges might build and create a large risks to ignite fuel sources in the area. The Canadian Centre for Occupational Health and Safety Fact Sheet on safe working conditions with static electricity covers which solvents might be hazardous as well as the possible risks associated with each fluid.

The automotive realm bridges the gap between the workers on the factory floor and end users driving the vehicles. Antistat, a company focusing on grounding equipment, published an article about the hazards of electrostatic discharge in an automotive facility and how it poses a danger to the workers and the infrastructure. It then tied such hazards to accidents that hurt production throughput.

The Petroleum Equipment Institute has been investigating electrical fires that occur around vehicle refueling since the 1990s. The company’s Stop Static campaign aims to help drivers prevent the possibility of igniting gasoline vapors near gas pumps. (FYI, the article also notes that no instances of cell phone usage has ever ignited a phone and cites the MythBusters episode as further evidence.)

On the bigger scale of space exploration, NASA also keeps an eye on static charge buildup and the possible effects of a spark occurring at the wrong time. The paper “Mitigation of Electrostatic Hazards on Spacecraft” discusses discharge concerns around spacecraft. It also outlines several areas of possible charge buildup, such as fueling, contact and separation of fuel tanks, extravehicular activities, and the interaction of the rocket surface and ice clouds. NASA’s main concern is the explosion of hydrogen gas that might be present in or around a spacecraft.

EMI, EMC and HIRF Testing

The Federal Aviation Administration (FAA) controls the High-Intensity Radiated Fields (HIRF) requirements. Regulation 29.1317 states that “each electrical and electronic system that performs a function whose failure would prevent the continued safe flight and landing of the rotorcraft” must meet certain conditions. Meanwhile, the National Institute of Standards and Technology (NIST), an agency that never explains something complicated with a quick summary, released the NISTIR 3839 EMC Standards and Regulations: A Brief Review. The 40-page document outlines electromagnetic capability standards for electronics components.

Meeting EMC standards means that you’re keeping your system safe from electromagnetic interference. This can mean testing a product at four levels:

1. The component level
2. The board level
3. The system level
4. The assembly level

Testing to achieve certification for a product can be costly and takes time. Failing a certification test is a sure way to pile on more costs and time to a product.

“OEMs are designing new vehicles to be sleeker and lighter. This typically requires the removal of cable harness shielding, which creates EMI vulnerabilities,” said Shane Emswiler, senior vice president of products at Ansys. “Designing cable harnesses with EMA3D Cable will help engineers mitigate safety-critical EMI issues—including HIRF, lightning strikes, crosstalk and electromagnetic pulses—drastically improving certification support and reducing design expenses.”

Building on Ansys SpaceClaim

EMA3D Charge is built on top of SpaceClaim, an Ansys tool that lets users manipulate imported CAD geometry. SpaceClaim also gives users the ability to design and model new parts, assemblies or drawings. With SpaceClaim, the geometry features of models can be removed to ease mesh complexity for simulation, jigs and fixtures can be designed around imported components for manufacturing applications, and data can be analyzed and repaired to facilitate faster 3D printing.

EMA3D and Ansys previously partnered on cable validation. (Image courtesy of EMA3D.)

Now EMA3D Charge takes these capabilities from SpaceClaim and knits them together with different physics solvers. The simulation tool was designed to target four major challenges:

1. Charging analysis needs to have accurate enough information to find out where, when and what type of electric arc might be created in a component.
2. The software needs to be able to use plasma and material physics to predict charge accumulation on satellites and space platforms.
3. The catastrophic failure of satellites from discharge events needs to be predicted and controlled, as Ansys notes that testing in space is nearly impossible.
4. The software needs to manage electrostatic discharges in air and solid dielectrics—tasks that generally require several different simulation tools.

What Does It All Mean?

EMA3D Charge is built to simulate cable harnesses, understand the areas of electrical charge buildup, and predict the areas where discharge might occur. The focus is on the safety of workers, drivers and astronauts who might be in an area where electrostatic discharge could cause harm to equipment or themselves. That goal is coupled with Ansys’ overarching goal of simulation, condensing the product development process and making the system more efficient.

Ansys has a huge catalog full of proven products and one thing the company does well is listen to its customers about how to push those products into new markets and make small or big changes to give new functionality. Another trait of Ansys is partnering with other simulation and software companies to take components from two or more different tools and create a very specific new solver. Working with EMA3D to take its preexisting cable simulation tool (created from a previous Ansys partnership) and tweaking it to create a specialized solver is another great example of the company’s ability to release new and useful products.

Some of these partnership and simulation release articles over the past few years have later resulted in follow-ups where the larger company has acquired or absorbed the smaller software company. That doesn’t appear to be the case yet with Ansys and EMA3D, but time will tell. In the meantime, watching what engineers do with this new charge and discharge tool will be very interesting.