Design Considerations for SAE ARP 4989 Enclosed Turboshaft Engine Test Cells

The SAE ARP 4989 standard, developed by the Society of Automotive Engineers (SAE), has been developed by a large team of staff from the aerospace industry and government agencies, and provides the latest information for use by individuals and organizations designing new or upgraded turboshaft engine test facilities.

The objectives of this standard are as follows:can also be listed as:

• To provide guidelines for the design of state-of-the-art ground-level closed test facilities for turboshaft engine testing.
• To consider the physical, aerodynamic and acoustic properties of the main test cell engine load absorber that will affect the operation, performance, accuracy and stability of a tested engine.
• Consider acoustic and environmental effects and methods of controlling them.

A turboshaft engine is a type of jet engine designed to generate shaft power rather than thrust. Turboshaft engines are most commonly used in applications that require a small but powerful, lightweight engine, including helicopters and auxiliary power units. A turboshaft engine works on the same principles as a turbojet to generate energy, i.e. there is a compressor, combustion chamber and turbine inside the engine's gas generator.

The main difference between turboshaft and turbojet is that an additional power section consisting of turbines and an output shaft is included in the design. In most cases, the power turbine is not mechanically connected to the gas generator. In this design, the engine by itself allows the speed of the power turbine to be optimized for the machines it will energize.

A turboshaft engine is very similar to a turboprop engine, and there are many engines of both types. The main difference between the two is that the turboprop version must be designed to support the loads of the attached propeller, while a turboshaft engine is not normally as robust as it drives a transmission that is structurally supported by the vehicle and not the engine itself.

Among the numerous test, measurement, analysis and evaluation studies it provides for businesses in various sectors, our organization also provides testing services for closed turboshaft engine test cells within the scope of SAE ARP 4989 standard, with its trained and expert staff and advanced technological equipment.