Designing new products, and new categories of products, often involve solving problems that have not previously been confronted. Sometimes, we don’t know what we don’t know. So, it’s important to work with people who can ask the right questions and help bring together the critical pieces of a solution.
Companies like Uber already know how to efficiently move people by car from point A to point B in crowded communities. But they don’t know as much about urban transportation by air, which many see as the future of commuting, and a viable way for people to avoid traffic congestion on the ground. Uber Elevate is looking at electric vertical take-off and landing (eVTOL) aircraft as an affordable way to decrease commute time while eliminating fossil fuel emissions and noise pollution. This is a new market within aerospace called urban air mobility (UAM).
UAM travel takes companies beyond current core competencies and into unknown territory. It forces engineers to think differently about commuting and find solutions to problems they could not anticipate in giving flight to a new type of aircraft. Parker Aerospace’s Gas Turbine Fuel Systems Division (GTFSD) is in a unique position with an extensive pedigree to support companies as they develop the first generation of UAM aircraft.
Parker’s experience designing thermal management (TM) solutions for U.S. military aircraft includes aerospace coolers (e.g. heat exchangers and liquid-cooled chassis), single- and two-phase liquid cooling solutions with cold plates, cooling pumps, and liquid-filled enclosures, which are likely technologies to be transferred into the development of electric aircraft used for urban mobility. Experience with the Federal Aviation Administration (FAA) and other federal agencies could also save companies time and expense meeting regulatory and other government obligations.
Sophisticated electronic systems used in defense applications are creating significant increases in power densities on various military platforms. Many of the leading TM technologies in use today reside within one-time-use missile systems. However, other emerging military applications on aircraft, ships, and submarines add more layers of complexity to TM applications. They often have multiple pieces of heat-generating hardware in close proximity to each other, requiring greater levels of heat dissipation and control over multiple uses.
Parker Aerospace is overcoming heat problems in military applications with new approaches in TM design. Several use fluids to manage heat. Single-phased cooling works by transferring heat through fluids only. Two-phased cooling turns fluids into gas, which is a more efficient way to dissipate heat. Both are used in closed-loop systems, meaning the fluids and gas stay contained. Parker has deep experience in both cooling methods.
A liquid-cooled enclosure manages heat at its source. Components completely enclosed in dielectric or similar fluids that don’t conduct electricity can safely function while the fluid absorbs and dissipates the heat from the components. Parker TM enclosures function as mechanical structures to protect sensitive electronics from shock, vibration, heat, and other environmental threats.
Heat rejection technologies also provide cooling with fluid in space-constrained environments, transferring large amounts of heat from fluids to surrounding air or to secondary fluids. Liquid-cooling technologies can be applied to chassis and other components, but also to entire systems within aircraft.
Another TM approach uses cold plates, which provide localized cooling of hot spots. These cooling solutions are suitable for power electronics and computing applications. For example, heat-generating circuit cards can be mounted on the face of cold plates. Where the circuit card touches the cold plate, the liquid is heated, moved, and cooled down with a radiator-like arrangement, which then returns cool fluid to the heat source. Like enclosures, cold plates could become part of a larger structure to add functionality. Imagine a heat exchanger that becomes a ring around the outside of a jet engine.
Read our prior blog article to learn more about thermal management in defense applications: Selecting a Thermal Management System Supplier for Aerospace and Defense
Parker’s experience outside the aerospace and defense industries can also benefit urban air mobility aircraft, an emerging market in the aerospace industry. The company’s large and diverse portfolio of manufacturing know-how in many industries is being applied to the challenges faced by UAM aircraft. Macro-laminate bonding TM (fusion bonding), two-phase evaporative cooling, and vacuum brazing all have benefits to offer TM challenges.
With conventional brazing, for example, it is difficult to make small passageways void of flux for efficient fluid passage, particularly if the geometries of the passageways are complex. But with vacuum brazing, the intermediate materials do not contaminate passageways. Fusion Bonding takes place at the molecular level and high aspect ratio microchannels are possible, completely free of residual debris.
SprayCoolTM technology is a technique in which liquid droplets are sprayed directly onto hot components. When the droplets evaporate, they take excess heat with the evaporated fluid. The liquid and vapor mixture can then be transferred to a heat exchanger where the vapor is cooled, condensed, and recycled within a closed system.
In the not-so-distant future, cold plates are expected to become more sophisticated for all-electric aircraft. Right now, the U.S. military is the leading customer for the next generation of cold plates being developed. New cold plates are expected to become more common in commercial applications. They will also see extensive use in the air mobility market. In addition, as commercial transports continue to evolve and become more eco-friendly, there will also be a need for cold plate technologies in commercial transports.
Parker divisions collaborate with many diverse customers and develop solutions that are unique and valuable to specific customer applications.
“Solving problems is sometimes achieved by using technologies of which customers are not aware of. Design and engineering expertise within a broad range of technologies offers Parker customers a wide array of options to pursue, which solve not only technology challenges, but also minimize risks, reduce carbon footprints, improve performance, and achieve other corporate goals.”
— Roy McEvoy, director of business development at Parker’s Gas Turbine Fuel Systems Division
As a trusted partner, Parker's team members work alongside customers to enable technology breakthroughs that change the world for the better. Parker's Purpose is at the core of everything we do. Watch the introduction video with Parker's CEO Tom Williams.
This blog was contributed by Michael Humphrey, business development manager for thermal management solutions, Gas Turbine Fuel Systems Division of Parker Aerospace.