Space Engine Systems
Space Engine Systems Inc. is a Canadian aerospace company and is located in Edmonton, Alberta, Canada. The main focus of the company is the development of a light multi-fuel propulsion system to power a reusable spaceplane and hypersonic cruise vehicle. Pumps, compressors, gear boxes, and other related technologies being developed are integrated into SES's major R&D projects. SES has collaborated with the University of Calgary to study and develop technologies in key technical areas of nanotechnology and high-speed aerodynamics.
Company history
Space Engines Systems Inc. was established in 2012 to develop the DASS engine and related technologies in the aerospace sector. Space Engine Systems's promoters have been involved in the development of the engine for over 20 years. work together to bring novel pumps, compressors, and gearbox systems to the aerospace industry as spin off applications. On May 10, 2012, SES publicly announced the launch of their company at the Farnborough Air Show. On August 6, they announced their participation in the AUVSI's Unmanned Systems North America. SES frequently attends major international trade shows in the aerospace sector including the Paris Air Show in 2013, 2015, and 2017 and the Farnborough Air Show in 2014, 2016, and 2024.DASS engine
The DASS engine is a pre-cooled combined cycle propulsion concept that can produce thrust over a wide range of vehicle flight Mach numbers. Derivatives of the engine can be used for propulsion of an SSTO vehicle, long-range missiles, and hypersonic transport aircraft. The engine is being developed with the flexibility for various vehicles and mission profiles. The concept uses existing aerospace technologies, including conventional gas turbine components, and new developments in nanotechnology to overcome some of the key technical obstacles associated with overheating and fuel storage. In high-speed flight, the incoming air has a very high dynamic pressure and aerodynamic deceleration results in a rise in static pressure and temperature. Temperatures can rise above the material limits of the compressor blades in a conventional turbojet. A strategy to alleviate this problem is to place a heat exchanger downstream of the inlet in order to reduce gas temperatures prior to mechanical compression. Similar to the deep-cooled turbojet or the liquefied air cycle engine, energy extracted from the incoming air in the DASS engine is added back into the system downstream as sensible heat in the fuel stream.The DASS engine concept improves upon the heat exchange process in multiple ways. Surface nano-coatings are placed on the internal heat exchangers to enhance convective heat transfer rates, reduce heat exchanger mass, and reduce unwanted aerodynamic blockage. Metallic nanoparticles are seeded into the intake air from the inlet cone to further enhance heat transfer. The particles act as a supplemental fuel and assist the operation of flow control devices downstream. It is known that metallic fuels have desirable storage properties in comparison to hydrogen and have excellent energy densities on a per volume basis. A combination of hydrogen and nanoparticles of Boron are being considered as the engine's fuel.
The main advantage of the DASS engine over conventional rocket engines for high-speed flight is the use of atmospheric oxygen in its air-breathing mode. The specific impulse of air-breathing engines are superior to rockets over a wide range of Mach numbers. These gains have the potential to realize a larger payload mass fraction. The higher Isp associated with air-breathing engines is a major motivation for the development of supersonic combustion ramjet engines. Airbreathing engines typically have a lower thrust-to-weight ratio compared to rockets. That is why the DASS engine will be integrated into a lifting-body vehicle. For an SSTO vehicle, reduced vehicle mass and increased payload mass fraction translates to lower operation costs. For transport, the ability to travel at hypersonic speeds drastically decreases the time required to cover long distances. The altitude at which hypersonic cruise vehicles operate is usually much higher than conventional transporters. The lower air density at these higher altitudes reduces the overall vehicle drag, which further improves efficiency. Current research and development is focused on engine operation at Mach 5 cruise at an altitude of 30 km. Note that 30 km is still significantly lower than what is considered to be the edge of space and much lower than low Earth orbit. Therefore, for the DASS Engine to operate beyond the target 30 km and Mach 5 operating conditions, the design will be modified. At higher altitudes the air density decreases and the vehicle must travel faster to achieve a sufficient inlet mass capture. At even higher altitudes, the DASS engine will need to store onboard oxidizer to be used with a rocket motor in its flow path. The target is to achieve a major component of orbital velocity when operating in the airbreathing mode before switching to the rocket mode.
Engine details
At low flight speeds the DASS engine relies solely on the on-board turbojet that runs on a conventional hydrocarbon fuel. The variable geometry intake allows large gaps to form between the heat exchanger, minimizing intake pressure losses. During this mode, the bypass is closed and all air is processed through the turbojet core. The exhaust nozzle contracts in the subsonic mode for optimal specific thrust. As the engine accelerates to supersonic velocities, the articulated portions of the intake direct flow into the heat exchanger. Liquid hydrogen fuel is passed through the heat exchanger, decreasing the temperature of the air prior to engine compression. Some of the air bypass the turbojet core, and is mixed with the hydrogen exiting the heat exchanger in the afterburner section. Note that the magnitude of heat transfer is coupled to the amount of hydrogen available for combustion in the afterburner. The combustion products are then expanded through a supersonic nozzle, variable geometry nozzle. The engine will be designed to completely consume the air to optimize for thrust. The level of bypass changes throughout the supersonic flight regime. The engine can operate at Mach 4 and provide thrust in excess of a conventional ramjet. At high Mach numbers air cannot be cooled below the turbojet limit. As a result, no combustion can occur in the core turbojet and the engine must transition into a pure ramjet mode. The variable inlet continues to articulate to completely block air access to the turbojet, while optimizing intake to exit area ratios for ramjet combustion using hydrogen. The engine still realizes an efficiency boost from the cooling effects of the heat exchanger. The terminal flight speed is limited to that of a hydrogen fueled ramjet.The goals of the DASS GN X and DASS GN1 engines are to provide efficient thrust from rest up to hypersonic speeds and high altitudes with a low specific fuel consumption along the entire flight path, and a small rocket stage to bring the vehicle into orbit. The engine will operate on multiple fuels. Each type of fuel has an advantage. The hydrocarbon fuel is typically used in turbojet/turbofan engines, which are considered mature/conventional technology. This engine will provide thrust at low-speeds. Hydrogen has a large heat capacity, so it is an excellent heat sink for the heat exchanger. It also has the best energy content per unit mass of any fuel and is a light molecule. As a result, it can provide large thrust levels with a low specific fuel consumption. Metallic fuel has excellent storage qualities, high energy content per unit volume, and can assist in convective heat transfer. It also has good combustion properties at nano-scale.
Key technology components of the DASS GN 1 and DASS GN X are quite similar. The DASS GN1 is meant exclusively for aerospace and the DASS GN X is meant for space applications only. An engine prototype is planned for ground and flight testing.
Engine comparison
The table below shows a comparison of the DASS engine to more conventional high-speed engines at two Mach numbers. Two types of Ramjets were considered. The first Ramjet uses a combination of fuels in similar proportions as the DASS engine. The second Ramjet uses pure hydrogen. It is clear that at the lower Mach number, the DASS engine provides a higher specific thrust. This is due to higher pressure that can be utilized by the turbojet. At Mach 4 the DASS GN1 performs similarly to a ramjet. At this speed, the DASS GN1 engine would likely convert to a pure ramjet. The specifications listed do not include any gains that might be realized through heat transfer on the intake cone, or from the combustion of metallic fuel. A typical rocket specific impulse is between 250 – 500 seconds.| Engine | Specific Thrust | Specific Fuel Consumption | Tmax/To | Pmax/Po | Isp |
| DASS GN1 | 4.23 | 30.9 | 15.1 | 23.9 | 3299 |
| Kerosene/H2 Ramjet | 3.41 | 38.4 | 15.1 | 6.0 | 2654 |
| H2 Ramjet | 3.44 | 28.5 | 15.6 | 6.0 | 3569 |
| Engine | Specific Thrust | Specific Fuel Consumption | Tmax/To | Pmax/Po | Isp |
| DASS GN1 | 3.67 | 30.0 | 17.8 | 228 | 3410 |
| Kerosene/H2 Ramjet | 3.64 | 30.1 | 17.8 | 57 | 3383 |
| H2 Ramjet | 3.65 | 26.9 | 18.0 | 57 | 3786 |
Ground Testing Facility
Space Engine Systems is developing a ground testing facility capable of simulating high temperature inlet flow at high altitudes associated with supersonic flight. The facility, named the Multi-Fuel Jet Engine testing facility, is highly modular and can easily be adapted for many applications. The facility includes:• Direct Connect System to supply high temperature air flow to the engine to simulate supersonic air flow up to Mach 5.
• Fuel System to supply multiple fuels to the engine, including liquid hydrogen, jet fuel, and solid nano-particles.
• Measurement Suite to allow data collection and analysis of all tested equipment.
The Multi-Fuel Jet Engine testing facility can be used to better understand:
• Pre-cooled combined cycle propulsion
• Temperature limitations of various turbine engine materials/components
• Multi-fuel combustion
• Multi-fuel afterburners
• Engine start modes at high altitude
• Thrust characteristics at high altitude
• By-pass ratio control
• Engine test-stand and mounting mechanisms
• Flow characteristics