Co-funded by the Regional Growth Fund, the Institute of Railway Research (IRR) has opened its new £4.5M laboratory facility. The advanced test equipment supports both the IRR’s new Centre for Innovation in Rail (CIR) and the wider railway research activities of the IRR. The laboratory will significantly boost fundamental research output at the University, and within the UK; advancing the science of wheel-rail interaction vehicle dynamics, materials technology and emerging research areas such as remote condition monitoring systems (RCM) and Big Data analytics as part of the developing digital railway.
Under the context of the newly formed CIR, the facilities also provide an advanced dynamic testing capability for the trialling and approvals of vehicle and track systems. Our equipment also supports a range of existing virtual testing and expert modelling services provided by the wider IRR team. These include mechanical dynamics, design optimisation and Finite Element modelling.
Our lab equipment includes:
The IRR’s full-scale rolling contact, adhesion and braking rig is unique in combining a large 2m diameter rotating rail drum with the capability to test a complete bogie assembly. This novel feature has formed a focus of the rig’s design and development cycle and is key to providing an accurate representation of the contact conditions which exist between wheel and rail, whilst maintaining the load cycle time and running speed benefits of a rotating type rig. As an additional capability, the test rig is fitted with an in-built lathe head, allowing any cross-sectional profile to be applied to the two rail sections of the rotating drum.
The fundamental components of the rig consist of a 2m diameter drum with two circumferential rails, a bogie manipulation platform and a loading frame and actuators to allow full-scale body vertical and roll motions to be imposed through the bogie’s secondary suspension.
The lead wheelset of the bogie under test is placed on the rotational rail drum whilst the trailing axle is fixed to the manipulation platform. This facilitates both bogie rotation and lateral displacement relative to the rails, allowing the leading wheelset to be manipulated to represent various steady-state curving scenarios.
Wheelset position can also be controlled explicitly via attachment of actuators directly to the axlebox’s of the IRR’s test bogie (Y25 freight bogie). This functionality allows precise control of the lateral displacement and angle of attack of the wheelset, a key benefit when studying the details of wheel-rail interaction and contact mechanics.
In addition to pure rolling of the wheelset, the rig incorporates the capacity to react up to 110kNm of braking torque, this is sufficient for complete slip (wheel-slide) between wheel and rail. When combined with the rig’s advanced hardware-in-the-loop control functionality, such a feature allows adhesion and braking performance of a bogie lead axle to be investigated. If a research partner provides a full traction package (motor and inverter drive) the test rig can also be used for lead axle traction tests under a range of user specified duty cycles.
Whilst the primary application of the rig is the study of wheel-rail interaction under a wide range of operating conditions, it is also possible to investigate bogie dynamics from the perspective of verifying suspension properties under full-scale loads. Examples include establishing the true effective primary yaw stiffness of a bogie (important for wheel-rail wear and rolling contact fatigue) and also secondary suspension behaviour such as bogie rotational resistance. The vertical performance of the suspension system can also be characterised through application of dynamic loads via the bogie centre-pivot.
Note that due to the adoption of a single large diameter rail drum, wheelset dynamics can be explored but there are some technical limitations in in terms of bogie running dynamic tests (stability and lateral ride).
The specification and typical applications of the rolling contact, adhesion and braking rig are detailed below:
The IRR’s advanced dynamic test cell provides a high load capacity facility for mechanical static and dynamic testing applications. With a 50t capacity loading system across a fully modular test floor of 10m x 4m, the rig can accommodate a wide range of test specimens and configurations.
With the support of IRR research staff, the test rig’s state-of-the-art hardware-in-the-loop control system can be used to design novel mechanical experiments which include elements of closed-loop dynamic co-simulation or measured load profile data extracted from the operating environment of the component under test.
Within the railway sector the rig is perfectly suited to high-cycle fatigue testing of complete trackform systems (slab and ballast) and their components. From a vehicle perspective performance of suspension components and fatigue testing of bogie frames and associated equipment are within the capabilities of the facility. These are purely examples and we welcome test application proposals from any discipline of engineering.
The specification and typical railway applications of the 50t advanced dynamic test cell are detailed below:
The IRR’s 6-axis motion platform has primarily been installed to support our vehicle dynamics investigations, particularly with respect to vehicle body movements and the replication of these within a laboratory environment. The platform and its installation have been designed to allow full-scale sections of vehicle bodies and their interiors to be tested.
The 6 axis platform allows vehicle body motions derived from dynamic simulations to be imposed on various elements of the train system. This may for example be passenger ride perception or evaluation of underframe mounted equipment from a mechanical fatigue perspective. The rig is also used for evaluation of energy harvesting systems or any other multi-disciplinary engineering testing whereby 6-axis motion control forms part of the testing requirement
The IRRs high performance computing cluster is the engine behind the Institute’s developing expertise in data analytics and natural language processing. Working with its strategic partner RSSB and industry sponsors the facility is available to solve problems which require multi-core processing technologies – typically those found in today’s data driven systems.
The facility is based upon x86 processors and is running a modern open source enterprise operating system. It will be instrumental in the continued development of Big Data for Risk Analysis research at the IRR, allowing data to be processed in volumes not possible with desktop machines. The specification and typical railway applications for the high performance computing cluster are detailed below:
The 1/5th scale railway roller rig consists of one bogie and two wheelsets, each is driven independently by a three phase AC motor. The motors can be controlled precisely by inverter drives. The rollers pairs are connected to two DC generators which are used to apply variable traction load between the wheel-roller interfaces.
A hardware in the loop system is built using this rig. Real-time sensor measurements are sent to a computer programme which simulates a traction controller thus sending control commands to the motor.
This rig can be used to evaluate wheel rail adhesion levels using traction motor parameters and also other research applications such as traction/braking control and regenerative braking studies.
The IRR have various track and vehicle measuring equipment including: