Non-exhaust brake dust and pollution arising from metal, semi-metal, and ceramic brake pads have made recent research consider their replacement by potential natural fibers such as hemp, flax, sisal, etc. These natural fibers are lightweight, biodegradable, and cheap. This paper discusses the wear and friction analysis of hemp fiber reinforced polymer brake pad material. Three test specimens viz. HF4P20, HF5P20, and HF6P20 were prepared per ASTM G99 standards for the pin-on disc tribo-test. The test trials and validation were done using the Taguchi design of experiments and ANOVA. The optimum result showed a consistent coefficient of friction and lowered specific wear rate for HF6P20 brake pad material. Worn surface morphology was done using scanning electron microscopy.

Three unique syntheses were developed and investigated. One with just hemp as reinforcing fibre (HFRC), the other with hemp and basalt fibres (HBFRC), and the third with hemp and aluminium strands ...

Thermoacoustic technology attracts significant attention from researchers due to its high reliability, environmentally friendly operation, and less maintenance. An overview of related theoretical models for thermoacoustics technology is used in this review paper to support an introduction to the thermoacoustic effect. The outline of the latest research work in thermoacoustic engine technology and the experimental setup is presented. In addition to this, the paper discusses the numerical analysis of thermoacoustic power generator. The majority of the innovations have been covered in this review, with recent examples being the generation of electric power setups. Interpretation of nonlinear effects in thermoacoustic systems and the innovation of nonlinear thermoacoustics need to receive more attention. For both theoretical and engineering study, discussions on fluid flow and heat transfer under turbulent and oscillating flow conditions will be instructive. These prime movers are utilized to operate the thermoacoustic driven refrigerator, crycooler, and also, used to generate electric power.

NAO brake friction materials with 4%, 5%, and 6% (w/v) sodium hydroxide treated hemp fiber reinforcement having 25% wt. fiber loading and fixed percentage of phenol formaldehyde resin content (20% wt.) along with other fillers have been studied and reported by the authors earlier. However, the effect of variations in the resin content on the tribological performance has been studied and reported in the present paper. Five variants were prepared with varying percentages of phenol formaldehyde resin from 12% wt. to 22% wt. with incremental steps of 2% wt, along with the optimum of 6% (w/v) sodium hydroxide treated hemp fibers and other fillers. The prepared test variants’ tribological characterization was done using Taguchi’s L₂₅ orthogonal array on a pin-on-disc experimental setup, as per ASTM G99, at room temperature and compared with the best of the earlier studied friction composite. Fade and recovery tests of the best of the earlier studied and present ones were performed on a chase tribology tester per SAE J661 standards. The results revealed moderate coefficient of friction of 0.4496, lower wear rate of 0.57 gm, and better fade recovery for the HF25P20 variant compared to its counterparts studied here.

Confined fire environments in marine and industrial compartments present serious safety challenges due to rapid heat accumulation, restricted ventilation, and complex buoyancy-driven flow behavior. Accurate prediction of propagation of heat and development of plume is important for the effective and efficient design of thermal detection and mist-based fire suppression systems. In the present study, a 2D transient Computational Fluid Dynamics analysis has performed to investigate buoyancy-driven heat transfer generated by heat source of 0.5 m diameter maintained at 450 °C inside a closed container of dimensions 2.6 m × 2.6 m. The air was considered as the working fluid, and natural convection was modeled to capture plume rise, entrainment, and thermal stratification effects. The heat source was sequentially positioned at four diagonal locations: D1 (0.65 m, 0.65 m), D2 (1.95 m, 0.65 m), D3 (1.95 m, 1.95 m), and D4 (0.65 m, 1.95 m) to assess the influence of source orientation relative to enclosure (Container) boundaries. The numerical methodology incorporates mesh-independence verification, transient time-step control with Courant numbers maintained below 2, appropriate turbulence modeling, and strict mass conservation to ensure numerical accuracy. The simulation reveals the formation of strong buoyancy-driven thermal plumes with peak velocities in the range of 0.9–1.3 m/s. Lower heat source configurations produce tall vertical plumes, while upper source placements result in early plume impingement and the development of ceiling jets, significantly enhancing lateral heat transport. Temperature and density fields indicate localized high-temperature zones near the heat source, with air density reducing to approximately 0.5–0.7 kg/m³ within plume cores. Turbulent kinetic energy reaches peak values of the order of 10⁻² m²/s² along plume shear layers and ceiling interaction regions, reflecting intense mixing. Pressure and mass imbalance analyses confirm stable transient behavior, with mass imbalance remaining within ± 10⁻⁷ kg/s. The findings present design trends under idealized enclosed conditions, which may support future development of fire detection and suppression strategies for marine and industrial compartments after further validation under realistic operating conditions.