We review observations on the chemical enrichment of the intracluster medium (ICM) performed using BeppoSAXMECS data. The picture emerging is that non-cooling flow clusters have flat metallicity profiles, whereas a strong enhancement in the abundance is found in the central regions of the cooling flow clusters. All the non-cooling flow clusters present evidence of recent merger activity suggest...

Boundary layer behavior over a moving continuous surface is an important type of flow occurring in several engineering processes. For example, many metallurgical processes involve the cooling of continuous strips or filaments by drawing them through a quiescent fluid. However, by drawing such strips in an electrically conducting fluid subject to a magnetic field, the rate of cooling can be cont...

one of the most important methods of transporting natural gas in iran and other parts of the world is the utilization of a network of pipelines. compression station and turbo compressor units play an important role in gas supply through pipelines. one of the primary concerns in these units is the reduction of fuel consumption. by cooling of exhaust gas from the source station, the pressure drop...

We report the results of recent numerical simulations of the head-on merger of a cooling flow cluster with an infalling subcluster of galaxies. The objective of these simulations was to examine the effects of different types of cluster mergers (with 16:1 and 4:1 mass ratios) on the evolution of cluster cooling flows (with mass accretion rates of 100 and 400 M⊙/year). The 2-dimensional simulatio...

In this paper, using parabolic mirrors, a solar field was designed, which was related to a storage tank for a residential complex in the city of Tafresh located in the center of Iran. The design was performed for the existing oils: VP1, THERMINOL 66, THERMINOL 59. Finally, considering an organic cycle with R123 as working fluid and assuming a minimum length required for oil flow rate to reach a...

A Phase Doppler Particle Analyzer (PDPA) system is employed to measure the two-phase mist flow behavior including flow velocity field, droplet size distribution, droplet dynamics, and turbulence characteristics. Based on the droplet measurements made through PDPA, a projected profile describing how the air-mist coolant jet flow spreads and eventually blends into the hot main flow is proposed. T...

Temperature control during the cutting process with different parameters such as cutting velocity and applying water cooling is essential to decrease the cutting force, increase the life of the cutting tool and decrease the machined surface temperature of work-piece. In this research, the temperature of machined surface and the chip-tool interface in orthogonal cutting process of Ti-6Al-4V were...

Large-eddy simulations are performed to analyze film cooling in supersonic combustion ramjets (Scramjets). The transonic film cooling flow is injected through a slot parallel to a Ma = 2.44 main stream with a fully turbulent boundary layer. The injection Mach number is Mai = 1.2 and adiabatic wall conditions are imposed. The cooling effectiveness is investigated for adverse and favorable pressu...

We propose a scenario in which a large fraction, or even most, of the gas cooling to low temperatures of T < 10 K in cooling flow clusters, directly gains energy from the central black hole. Most of the cool gas is accelerated to nonrelativistic high velocities, vj ≃ 10 3 − 10 km s, after flowing through, or close to, an accretion disk around the central black hole. A poorly collimated wind (or...

Cooling flows in galaxy clusters and isolated elliptical galaxies are a source of mass for fueling accretion onto a central supermassive black hole. We calculate the dynamics of accreting matter in the combined gravitational potential of a host galaxy and a central black hole assuming a steady state, spherically symmetric flow (i.e., no angular momentum). The global dynamics depends primarily o...