A feasibility study of dynamic stress analysis inside a running internal combustion engine using synchrotron X-ray beams

Abstract

The present investigation establishes the feasibility of using synchrotron-generated X-ray beams for time-resolved in situ imaging and diffraction of the interior components of an internal combustion engine during its operation. The demonstration experiment was carried out on beamline I12 (JEEP) at Diamond Light Source, UK. The external hutch of the JEEP instrument is a large-scale engineering test bed for complex in situ processing and simulation experiments. The hutch incorporates a large capacity translation and rotation table and a selection of detectors for monochromatic and white-beam diffraction and imaging. These capabilities were used to record X-ray movies of a motorcycle internal combustion engine running at 1850 r.p.m. and to measure strain inside the connecting rod via stroboscopic X-ray diffraction measurement. The high penetrating ability and high flux of the X-ray beam at JEEP allowed the observation of inlet and outlet valve motion, as well as that of the piston, connecting rod and the timing chain within the engine. Finally, the dynamic internal strain within the moving connecting rod was evaluated with an accuracy of ~50 × 10(-6).

Engineering Science at the I12 Beamline at Diamond Light Source

“…Baimpas et al [21] used this technique to determine the elastic strain in the connecting rod of a combustion engine during operation ( Figure 6). The exposure time for each revolution was 0.3 ms, with total accumulated exposure time amounting to 24 s during 80 min overall engine running time.…”

“…The main aims in this study were to measure the [21]). dynamic strain that the ball exerts on the outer raceway of the bearing while the bearing was rotating and compare it to the static strain that a ball exerts on the outer raceway when it is stationary.…”

Microsecond time-resolved X-ray diffraction for the investigation of fatigue behavior during ultrasonic fatigue loading

“…The domain between femtosecond and nanosecond is mainly of interest to the solid-state physicists (Wark, 1996), particularly through the study of short-term crystal structure changes (Robinson et al, 2016;Fons et al, 2014), formation of crystalline structures during chemical reactions, effect of high pressures related to the propagation of a shock wave (Luo et al, 2012), rotation of side chains of proteins, etc. The domain between the microsecond and the millisecond opens the field to numerous other applications in engineering and material science (Gorfman, 2014): crack propagation (Rack et al, 2014(Rack et al, , 2016, fatigue of materials (Park et al, 2007), piezo electric response of materials (Cornelius et al, 2017), stress measurement in a rotating engine (Baimpas et al, 2013) or in the outer raceway of a bearing test (Mostafavi et al, 2017), etc.…”

Thermal behavior of single-crystal scintillators for high-speed X-ray imaging

“…A particularly compelling application of X-ray imaging is to study dynamic phenomena, including applications as diverse as the fluid dynamics of fuel injection and sprays (Moon et al, 2014;Halls et al, 2017), mechanical motions inside devices (Baimpas et al, 2013), the flow of blood in blood vessels (Jamison et al, 2012), shock-wave propagation (Olbinado et al, 2017) and the dynamics of metallic foam formation (Rack et al, 2009). To study highly dynamic phenomena, where fast framing rates and short exposure times are essential, a high visible light output from the scintillator is essential, necessitating an intense X-ray beam.…”