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The structure-, fluid- and air-borne excitation generated by HVAC compressors can lead to annoying noise and low frequency vibrations in the passenger compartment. These noises and vibrations are of great interest in order to maintain high passenger comfort of EV vehicles. The main objective of this paper is to develop a numerical model of the HVAC system and to simulate the structure-borne sound transmission from the compressor through the HVAC hoses to the vehicle in a frequency range up to 1 kHz. An existing automotive HVAC system was fully replicated in the laboratory. Vibration levels were measured on the compressor and on the car body side of the hoses under different operational conditions. Additional measurements were carried out using external excitation of the compressor in order to distinguish between structure- and fluid-borne transmission. The hoses were experimentally characterised with regard to their structure-borne sound transmission characteristics.

A typical high-pressure hose assembly consists of hose made with synthetic polymer braids and Teflon tube crimped with metallic fittings. These hose assemblies are mainly used for aircraft landing gear application considering its high-pressure sustenance and better flexibility. The proposed study investigates the effect of thermo-mechanical stress generated due to cyclic soaking and flexibility testing at thermostatic subzero (-65°F) and high temperature (+275°F) on performance of high-pressure hose assembly. This effect is further studied through hose tear-down which was envisioned to investigate the hose layer degradation and focused on changes in inner PTFE tube, which ultimately leads to product performance issues. Keywords: braids, tear down analysis, thermo-mechanical, inter-layer abrasion.

Design for Manufacturing and Assembly (DFM+A), pioneered by Boothroyd and Dewhurst, has been used by many companies around the world to develop creative product designs that use optimal manufacturing and assembly processes. Correctly applied, DFM+A analysis leads to significant reductions in production cost, without compromising product time-to-market goals, functionality, quality, serviceability, or other attributes. In this two-day course, you will not only learn the Boothroyd Dewhurst Method, you will actually apply it to your own product design!

This specification covers a precipitation hardenable, corrosion- and heat-resistant nickel alloy in the form of seamless tubing 0.125 inch (3.18 mm) and over in nominal OD and 0.015 inch (0.38 mm) and over in nominal wall thickness.

This specification covers aircraft-quality, low-alloy steel in the form of round, seamless tubing.

This document covers all metal, self-locking wrenching nuts, plate nuts, shank nuts, and gang channel nuts made from a corrosion and heat resistant steel of the type identified under the Unified Numbering System as UNS S66286 and of 160 ksi tensile strength at room temperature, with maximum test temperature of parts at 1200 °F.

This specification covers a titanium alloy in the form of welding wire (see 8.5).

This procurement specification covers the requirements for metal tube support clamps comprising of two spring clips made of corrosion and heat resistant steel and the associated PTFE single split cushion that supports the tube. See Figure 1.

This procurement specification covers tubular, blind rivets fabricated from a corrosion resistant nickel-copper alloy of the type identified under the Unified Numbering System as UNS N04405, and of 52 ksi minimum shear strength for self-plugging style rivets.

This specification covers a premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.

This specification covers a corrosion- and heat-resistant steel in the form of bars, wire, forgings, mechanical tubing up to 5.00 inches (127 mm), inclusive, in nominal diameter or least distance between parallel sides (thickness), and stock for forging or heading.

Unlike conventional heat shrink tubes or enclosure systems which only seals wires and splices on the outside, a novel Acrylate based sealing technology developed and introduced by Eurotech is a low viscosity fluid formulated to be applied to the splices either in liquid droplets or by dipping, utilizes fast capillary-wicking action and quick self-cure inside the wires to form a robust, cost effective, flexible, impenetrable seal to prevent moisture damage of wire harnesses and associated electrical components. This technology is an enabler of new wire harness architectures currently limited by the shortcomings of conventional sealing products such as heat shrink tubes which come up short when the splice configurations or geometries become too complex or difficult for sealing from the outside.

Side doors are pivotal components of any vehicle, not only for their aesthetic and safety aspects but also due to their direct interaction with customers. Therefore, ensuring good structural performance of side doors is crucial, especially under various loading conditions during vehicle use. Among the vital performance criteria for door design, torsional stiffness plays an important role in ensuring an adequate life cycle of door. This paper focuses on investigating the impact of several door structural parameters on the torsional stiffness of side doors. These parameters include the positioning of the latch, the number of door side hinge mounting points on doors (single or double bolt), and the design of door inner panel with or without Tailor Welded Blank (TWB) construction.

In electric vehicle applications, the majority of the traction motors can be categorized as Permanent Magnet (PM) motors due to their outstanding performance. As indicated in the name, there are strong permanent magnets used inside the rotor of the motor, which interacts with the stator and causes strong magnetic pulling force during the assembly process. How to estimate this magnetic pulling force can be critical for manufacturing safety and efficiency. In this paper, a full 3D magnetostatic model has been proposed to calculate the baseline force using a dummy non-slotted cylinder stator and a simplified rotor for less meshing elements. Then, the full 360 deg model is simplified to a half-pole model based on motor symmetry to save the simulation time from 2 days to 2 hours. A rotor position sweep was conducted to find the maximum pulling force position. The result shows that the max pulling force happens when the rotor is 1% overlapping with the stator core.

By introducing the yield strength ratio λ of strengthened ridgeline to plate and the strengthening coefficient multiplier R, the theoretical prediction expression of maximum bending moment of thin-walled square tube with strengthened ridgelines under static cantilever bending condition is obtained. Then the software of Hypermesh 13. 0 was used to establish two quasi-static finite element simulation comparison models under the corresponding static cantilever conditions. One model was designed for the original material thin-walled square tube, and another one was designed for the thin-walled square tube with strengthened ridgelines. After that, the LS-DYNA 971 solver was introduced to perform the solution calculations. Through a series of simulation calculations and result analysis, the accuracy of the theoretical expression for the maximum bending moment of a thin-walled square tube with strengthened ridgelines was verified.

With the rapid development of electric vehicles, the demands for lithium-ion batteries and advanced battery technologies are growing. Today, lithium-ion batteries mainly use liquid electrolytes, containing organic compounds such as dimethyl carbonate and ethylene carbonate as solvents for the lithium salts. However, when thermal runaway occurs, the electrolyte decomposes, venting combustible gases that could readily be ignited when mixed with air and leading to pronounced heat release from the combustion of the mixture. So far, the chemical behavior of electrolytes during thermal runaway in lithium-ion batteries is not comprehensively understood. Well-validated compact chemical kinetic mechanisms of the electrolyte components are required to describe this process in CFD simulations. In this work, submechanisms of dimethyl carbonate and ethylene carbonate were developed and adopted in the Ansys Model Fuel Library (MFL).

The need for eco-friendly vehicle powertrains has increased drastically in recent years. The most critical component of an electric vehicle is the battery pack/cell. The choice of the appropriate cell directly determines the size, performance, range, life, and cost of the vehicle. Lithium-ion batteries with high energy density and higher cycle life play a crucial role in the progress of the electric vehicle. However, the packaging of lithium-ion cells is expected to meet lots of assembly demands to increase their life and improve their functional safety. Due to their low mechanical stability, the lithium-ion cell modules must have external pressure on the cell surface for improved performance. The cells must be stacked in a compressed condition to exert the desired pressure on the cell surface using compression foam/pads. The compression pads can be either packaged between each cell or once in every set of cells based on the cell assembly requirements.

The process of assembling the bearing and crimp ring to the steering pinion shaft is intricate. The bearing is pressed into its position via the crimp ring, which is tipped inward and fully fitted into a groove on the pinion shaft. Only when the bearing is pressed to a low surface on the pinion shaft, the caulking force for the crimp ring is achieved. The final caulking distance for the crimp ring confirms the proper bearing position. Simulating this transient fitting process using CAE is a challenging topic. Key factors include controlling applied force, defining contact between bearing and pinion surface, and defining contact between crimp ring and bearing surface from full close to half open transition. The overall CAE process is validated through correlation with testing.