Two shell-and-tube heat exchangers (STHXs) using continuous helical baffles instead of segmental used in conventional STHXs were proposed, designed, and tested this study. The two proposed have the same tube bundle but different shell configurations. flow pattern side exchanger with was forced to be rotational due geometry baffles, which results a significant increase transfer coefficient per unit pressure drop exchanger. Properly designed can reduce fouling prevent flow-induced vibration as...

The valve is a critical component in compressors, significantly affecting their efficiency and reliability. performance of the reed can be largely influenced by lift limiter. However, current methods for determining optimal profile limiter lack scientific rigor, relying primarily on empirical observations trial-and-error approaches. This study proposed an enhanced design process profile, aiming to minimize maximum stress while ensuring its motion. A fluid-structure interaction (FSI) model...

Abstract This study conducted a numerical simulation of the gas leakage process in space station based on thermodynamic and fluid dynamic models, aiming to explore variations pressure temperature under different leak aperture conditions. The research first established mathematical model describing inside station, assumptions ideal behavior uniform distribution. It introduced effects adiabatic expansion radiative cooling, constructing system differential equations for changes. Through...

Purpose To find the optimal number of channels rocket engine thrust chamber, it was found that channel is 335, at which cooling effect chamber reaches best, can be helpful to design chamber. Design/methodology/approach The commercial computational fluid dynamics (CFD) software FLUENT with standard k ‐ ε turbulent model used. CFD method validated via comparing available experimental data. Findings It both highest temperature and maximal heat flux through wall on hot‐gas side occurs about...

The reed valves used as suction in reciprocating compressors are more susceptible to damage due the limitation of lift limiter which can't completely block entire valve plate. This article proposed a novel featuring redesigned shape aimed solve this issue. Compared conventional valves, could effectively mitigate highest stress occurring at root valve. To thoroughly investigate characteristics type and improve its performance, three-dimensional fluid–structure interaction (FSI) model was...

Compact heat exchangers are used in a wide variety of applications. Typical utilization is low-cost recuperator for power generation microturbines. In this scenario, takes from the exhaust gas and preheats compressor discharge air before it reaches combustion chamber. To achieve thermal efficiency over 30%, recuperators with high performance surfaces geometries needed. It has been shown that Cross-Wavy Primary Surface (CWPS) superior commercial potential compact based on previous studies....

Recent years, Genetic Algorithm (GA) technique has been gotten much more attention in solving real-world problems, successful genetic algorithms applications to engineering optimization have shown the strong ability of global searching and optimizing based on various objectives for their optimal parameters. The may be applied complicated heat exchangers is particularly useful new types. It important optimize exchanger, minimum volume/weight save fabrication cost or improved effectiveness...

Three-dimensional numerical simulation was conducted to investigate the flow field and heat transfer performance of Cross-Wavy Primary Surface (CWPS) recuperators for microturbines. Using high-effective compact achieve high thermal efficiency is one key techniques in development microturbine recent years. Recuperators need have minimum volume weight, reliability durability. Most important all, they thermal-effectiveness low pressure-losses so that gas turbine system can performances. These...

Compact and efficient recuperator is an important component of a microturbine system. To ascertain the optimum gas cavity configuration in 100kW-microturbine system, numerical study flow performance has been done. The main parameters to change different cases are cone angle pipeline, α depth pipeline cavity, L. By comparing pressure drop, Δp outlets velocity nonuniformity, Su, we found that case with = 5° L 370mm best configuration. Comparing worst case, it may greatly decrease nonuniformity...

Heat transfer of modem liquid rocket cngine thrust chamber mainly indicates the repeat coeling rockct nozzie, The chambers are exposed

Abstract The fluid flows and heat transfer characteristics of a tube with internal longitudinal fins were investigated experimentally numerically. realizable turbulence model was adopted to simulate the problem, whose results indicate good agreement measured data. Compared circular annulus tube, it shown that finned provides excellent performance greater than those great increase simultaneous pressure drops. Furthermore, there exists critical Reynolds number, about 1500, when number is less...

Measurements of various parameters in the flows through a cascade at different angles attack have been performed. The parameters, such as Reynolds stresses (uu/U2, vv/U2, and uv/U2), pressure distribution on blade surface, velocity passage, position separation point, so on, are measured large angle with separations. In addition, development wake is also investigated. A new formula second-order accuracy has developed to analyze hot-wire signals high turbulence intensity. data compared those...