Double Inlet System Research Articles

Optimal structure design and heat transfer characteristic analysis of X-type air-cooled battery thermal management system

This paper develops an X-type double inlet and outlet symmetrical air-cooled battery thermal management system (BTMS) that overcomes the high temperature, large temperature difference, and high power dissipation problems. The proposed method extends previous symmetrical BTMSs, i.e., single inlet and outlet BTMS, single inlet and double outlet BTMS, and double inlet and single outlet BTMS. However, compared with the existing symmetrical BTMS, the suggested X-type BTMS improves performance and reduces the maximum temperature, maximum temperature difference, and maximum power dissipation by 4.33 K, 74 %, and 62.9 %, respectively. Additionally, the inlet and outlet parameters of the X-type BTMS are optimized with orthogonal analysis, and the optimum settings defined as 71 mm near the outlet, 135 mm near the inlet, 90° for the outlet angle, and 150° for the inlet angle, among which the outlet position and inlet angle significantly affect the performance of the BTMS. The original X-type BTMS is optimized to reduce the maximum temperature and maximum temperature difference by 4 K and 76.5 %, respectively. Furthermore, the heat transfer correlation expression for the X-type BTMS is obtained through theoretical analysis within an 8 % deviation, providing a reference for the design of BTMS.

System dynamics model of output of ball mill

Abstract At present, the economic benefits of double inlet and double outlet ball mills, which are commonly used in coal-fired power plants, need to be improved. Based on this, this paper explores the factors influencing the output of double inlet and double outlet ball mill by establishing the output system of double inlet and double outlet ball mill. By analyzing the influence factors of the output of double inlet and double outlet ball mill, and combining with system dynamics, the dynamic model of double inlet and double outlet ball mill output system is established, and SPSS is used to fit the model data with the real data. The fitting degree is above 0.8, and the authenticity is high. The simulation results show that the impact energy of barrel grinding, the grinding powder fineness, and the pressure ratio in the ball mill affect the output of double inlet and double outlet ball mill according to certain relations. Finally, the research in this paper provides theoretical and technical support for improving the economic benefits of double inlet and double outlet ball mills.

Initial formation of channel–shoal patterns in double–inlet systems

Initial formation of channel–shoal patterns in double–inlet systems

Application of a method for calculating coal quantity feed into boiler for double inlet and outlet ball mill in the coordinated control system

Accuracy of the measurement of coal quantity feed into the boiler furnace has great influence on the combustion and coordinated control of power plant. According to the characteristics of double inlet and outlet mill pulverizing system, the method of calculating the amount of coal into furnace using the correlated variable was presented. On this basis, the coordinated control system was designed. Running results show that the method of calculating the fuel quantity accurately and effectively guarantee the stability of coordinated control system. It has a high adjustment quality.

An Eulerian-Lagrangian model to study the operation mechanism of Stirling pulse tube refrigerators

This paper is aimed to study the operation mechanism of Stirling pulse tube refrigerators (PTRs) by tracing working gas elements characteristics at the cold end of the system using both Eulerian and Eulerian-Lagrangian (E-L) methods. The main objective of the investigations is to demonstrate non-symmetry effects in the pulse tube section of the system. Elemental cyclic-enthalpy transfer of simple (S), double-inlet (DI) and multi-mesh regenerator (MM) PTRs are also investigated to demonstrate the effects of DI and MM systems on the refrigeration mechanism of PTRs. It is shown that the elemental cyclic-enthalpy transfer of SPTR is less than those of DIPTR, MMPTR and MMDIPTR, though it's elemental cyclic-temperature reduction is more than the others; because, the mass flow rate upon cold end of the SPTR is less than the others. Regarding the reduction of losses in DIPTR and MMPTR, their cold end mean pressure and density increase which consequently lead the cold end mass flow rate and cyclic-enthalpy transfer to increases. Increase in enthalpy transfer of MM-PTR, MM-DIPTR and DIPTR consequently improves their cooling performance.

Growth, yield and water use efficiency in drip irrigated brinjal (Solanum melongena L.) as affected by single and double inlet drip laterals

Experiments were carried out during three growing seasons of 2011 to 2013 in the farmer’s field at village Jamunali of Chhendipada block in the district Angul, Odisha, India. The effect of five different single and double inlet lateral connections with three different commonly available sub-main pipe sizes (40, 50 and 63 mm) on growth characteristics, yield and water use efficiency of drip irrigated brinjal (Solanum melongena L.) crop was studied. Maximum value of biometric observations such as plant height, girth at base, number of branches and leaves per plant, leaf area, root volume, root spreading diameter were found higher in case of double inlet system in comparison to single inlet system. Maximum tap root diameter, rooting depth, fruit length and fruit weight were found to be insignificant irrespective of the size of the submains connected with the laterals. However, except fruit weight all other plant characteristics were significant respective to the type of lateral connections. Water supplied through drip laterals connected with two submains of 63 mm diameter each at both sides of the plot showed better growth indicator parameters amongst the treatments. This performance also reflected in the case of yield and water use efficiency in cultivation of brinjal crop (Solanum melongena L.). Maximum yield (399.48 q/ha) and water use efficiency (880.58 kg/ha-cm) have been observed in case of double inlet system with two sub-mains of 63mm diameter and the lateral connecting to both the sub-mains at two ends (T 15 ). Minimum biometric values, yield (380.67 q/ha) and WUE (839.11 kg/ ha-cm) have been found in case of single inlet laterals laid on one side of sub main of 40 mm diameter (T 1 ) . Similarly, it is established that when single inlet systems with laterals laid at one side or both sides of the sub-main are converted to the corresponding double inlet systems by looping the laterals (L 1 to L 2 and L 3 to L 4 ), the growth parameters and yield of the system increases which is very easy to be achieved just by incorporating some minimal cost towards in-line laterals and connectors.

Modelling the influence of spatially varying hydrodynamics on the cross-sectional stability of double inlet systems

The cross-sectional stability of double inlet systems is investigated using an exploratory model that combines Escoffier’s stability concept for the evolution of the inlet’s cross-sectional area with a two-dimensional, depth-averaged (2DH) hydrodynamic model for tidal flow. The model geometry consists of four rectangular compartments, each with a uniform depth, associated with the ocean, tidal inlets and basin. The water motion, forced by an incoming Kelvin wave at the ocean’s open boundary and satisfying the linear shallow water equations on the f -plane with linearised bottom friction, is in each compartment written as a superposition of eigenmodes, i.e. Kelvin and Poincare waves. A collocation method is employed to satisfy boundary and matching conditions. The analysis of resulting equilibrium configurations is done using flow diagrams. Model results show that internally generated spatial variations in the water motion are essential for the existence of stable equilibria with two inlets open. In the hydrodynamic model used in the paper, both radiation damping into the ocean and basin depth effects result in these necessary spatial variations. Coriolis effects trigger an asymmetry in the stable equilibrium cross-sectional areas of the inlets. Furthermore, square basin geometries generally correspond to significantly larger equilibrium values of the inlet cross-sections. These model outcomes result from a competition between a destabilising (caused by inlet bottom friction) and a stabilising mechanism (caused by spatially varying local pressure gradients over the inlets).

Residual fluxes of suspended sediment in a tidally dominated tropical estuary

This paper assesses the fine sediment fluxes in the Caravelas estuarine system (Bahia, Brazil, 17o45'S and 039o12'W). The estuary reaches the ocean at the shore across from the Abrolhos Bank, the largest tropical reef habitat in the South Atlantic. The Caravelas estuarine system is composed of several meandering channels, which are connected to the ocean by a double inlet system. These two openings – the Caravelas and Nova Viçosa estuaries – are connected by a narrow, 30km long channel. The Caravelas estuary does not receive significant continental input, while the Nova Viçosa estuary receives the contribution of the Peruíbe River, which drains an area of approximately 5000km2. To understand the fine sediment dynamics and net transport, observations of tides, currents, salinity and suspended sediment concentration (SSC) were recorded in 13-h tidal surveys (spring and neap tide) and with 20-day long CTDs/ADCP moorings at the Caravelas estuary and in the interconnection channel. The SSC dynamic in the Caravelas estuary is primarily driven by advection, with SSC originating in the inlet and inner shelf area. Residual water and sediment transport are up-estuary in the Caravelas estuary and toward the Caravelas estuary in the interconnection channel. The residual transport showed pronounced synodical modulation and was stronger during spring tide. The Caravelas estuary function as a trap for inner shelf materials and fine sediments delivered by the Peruípe River at Nova Viçosa.

Effects of hypsometry on the morphodynamic stability of single and multiple tidal inlet systems

The evolution of the cross-sectional areas of tidal inlets draining the same back barrier lagoon is investigated with a simple model. The main new aspect is that hypsometry (cross-sectional area of the inlet and the wetted surface of the lagoon vary during the tidal cycle) is taken into account to determine the morphodynamic stability of the inlets. Results are presented for both a single and a double inlet system. In the double inlet system two inlets drain the same back barrier basin, which is divided into two sub-basins by a topographic high.The advection of the depth-averaged along-channel momentum results in an extra term in the momentum equation. The joint presence of hypsometric terms and this new term instigates a shift of the stable equilibrium cross-section to smaller values. The sole effect of the hypsometry of the inlet cross-section is a larger amplitude of the tidal current, causing a shift of the stable equilibrium cross-section to higher values. Similar conclusions are found in the case of a double inlet system. For this configuration also multiple stable morphodynamic equilibria are found, which strongly depend on the cross-sectional area above the topographic high. It further turns out that the morphodynamic equilibria are sensitive to changes in parameters that break the symmetry of the system, viz. the ratio of the surface areas of the back barrier basins, the ratio of the inlet lengths, the phase difference of the tidal wave and the cross-channel bottom slope of one of the inlets.

Entrance/exit losses and cross-sectional stability of double inlet systems

This study investigates the effect of entrance/exit losses on the cross-sectional stability of double inlet systems. The inlet is in equilibrium when the sand transport into the inlet equals the sand transport out of the inlet. The velocity amplitude corresponding with the equilibrium cross-sectional area is referred to as the equilibrium velocity (∼1 m s−1). This equilibrium is stable when after a perturbation the cross-sections of both inlets return to their original equilibrium value. The amplitudes of the inlet velocities are obtained using a lumped-parameter model in which the basin water level fluctuates uniformly (pumping mode) and where the inlets are schematized to prismatic channels. The system is forced by a semi-diurnal tide, where amplitude and phase may differ between the two inlets. Previous studies concluded that for double inlet systems no stable equilibriums can be found. However, in these studies entrance/exit losses were neglected. In the present study entrance/exit losses are included in the dynamic equation of the inlets.Using an analytical model it is shown that entrance/exit losses and a difference in the two ocean tidal amplitudes are a prerequisite for the existence of stable equilibriums. Furthermore, the effects of the addition of bottom friction and inertia to the dynamic equation are investigated using a mathematical continuation method. The results show that, provided entrance/exit losses are considerably larger than bottom friction and inertia, stable equilibriums are possible. These conclusions are supported by observations in the Ria Formosa, southern Portugal. Care should be taken in using the stability model described in this paper as a predictive tool due to simplifications in the model and the uncertainty in determining certain parameter values including inlet length, entrance/exit loss coefficient, bottom friction factor and equilibrium velocity. To alleviate these shortcomings suggestions are made for future research.

Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry for Detection of Nitrogen Containing Aliphatic and Aromatic Compounds: Resonance-Enhanced Multiphoton Ionization Spectroscopic Investigation and On-Line Analytical Application

Resonance-enhanced multiphoton ionization (REMPI) combined with time-of-flight mass spectrometry (TOFMS) is an analytical method capable of on-line monitoring of trace compounds in complex matrices. A necessary prerequisite for substance selective detection is spectroscopic investigation of the target molecules. Several organic nitrogen compounds comprising aliphatic and aromatic amines, nitrogen heterocyclic compounds, and aromatic nitriles are spectroscopically investigated with a tunable narrow bandwidth optical parametric oscillator (OPO) laser system providing a scannable wavelength range between 220 and 340 nm. These species are known as possible precursors in fuel-NO formation from combustion of solid fuels such as biomass and waste. A newly conceived double inlet system was used in this study, which allows rapid change between effusive and supersonic molecular beams. The resulting REMPI spectra of the compounds are discussed with respect to electronic transitions that could be utilized for a selective ionization of these compounds in complex mixtures such as combustion and process gases. The practicability of this approach is demonstrated by wavelength selected on-line REMPI-TOFMS detection of aniline and cyanonaphthalene in the burning chamber of a waste incineration plant. REMPI mass spectra recorded at different excitation wavelengths as well as variations in time show the utilization of species-selective REMPI-TOFMS detection for on-line monitoring of crucial substances in pollutant formation.

Experimental and theoretical studies on different ionic states of ethylthio CH3CH2S radical

A continuous flowing ethylthio CH3CH2S radical is produced in situ by pyrolysis of CH3CH2SSCH2CH3 at 242(±0.5) °C in a double heater inlet system on a double chamber UPS machine-II which was built specifically to detect transient species. By combining HeI photoelectron spectroscopic (PES) measurement with ab initio GAUSSIAN2 (G2) calculations on different ionic states of the CH3CH2S radical, we have concluded that the CH3CH2S radical has Cs symmetry and the ground state of the CH3CH2S+ cation is the A"3 state which comes from removal of an electron of the SHOMO 13a′ orbital for the CH3CH2S radical. The PES peak at the lowest ionization energy 9.08 eV with vibrational structure 700±60 cm−1 and corresponding with the G2 computed ionization energy 9.123 eV is designated to the A"3 ionic state. The removal of an electron of the HOMO 4a″ for the CH3CH2S radical leads to a very sharp peak at 10.31 eV, corresponding to ionization CH3CH2S+ (1A′)←CH3CH2S(X̃ 2A″) and the G2 computed ionization energy 10.322 eV. The A"1 ionic state caused by removal of the electron of the SHOMO 13a′ corresponds to the PES peak at 10.50 eV and the G2 computed ionization energy 10.448 eV. The assignment of the PES bands of the CH3CH2S radical in the high ionization energy region (>12.00 eV) is also supported by the G2 calculation. Both PES experiment and G2 calculations provide an evidence of existence of different ionic states for the CH3CH2S radical for the first time.

A new gas inlet system for an isotope ratio mass spectrometer improves reproducibility

We have developed a new inlet system for a gas sample isotope ratio mass spectrometer (IRMS). It is based on the well-known open split design from the gas chromatography/mass spectrometry (GC/MS) system due to its simplicity. The advantages over the conventional double inlet system with the metal bellows design include an improved reproducibility mainly due to a highly controllable pressure and temperature adjustment, a markedly lowered memory effect due to an uninterrupted gas flow through the ion source which limits adsorption/desorption processes on surfaces, and a single inlet capillary circumventing problems of asymmetrical behavior of sample and reference inlet paths. Furthermore, sample consumption is of the same order as for conventional measurements (i.e. about 0.4 mmol per hour), of which however only 2 &mgr;mol/h is used for the actual isotope ratio determination since the major gas amount acts as a gas flow seal against the atmosphere, corresponding to a 100-200 fold overkill. This may be improved in future systems. Copyright 2000 John Wiley & Sons, Ltd.

Bimolecular Reactions of Fluorine Atoms with CH3I and CH2I2

AbstractA fast flow reactor with a differentially pumped, double cone molecular beam inlet system into a quadrupole mass spectrometer is described. The total rate constants of the reactions F + CH3I, k2 = (1.68 ± 0.3) · 10−10 cm3 s−1 and F + CH2I2, k3 = (2.0±0.2)· 10−10 cm3 s−1 were measured at room temperature in this apparatus. The branching ratios for the HF and IF forming channels were determined in each case and consecutive processes are discussed.

ChemInform Abstract: MASS SPECTROMETRIC STUDIES OF THE IONIZATION AND THERMAL DECOMPOSITION OF TUNGSTEN PI‐CYCLOPENTADIENYL TRICARBONYL DIMER

J . R. KRAUSE and D. R. BIDINOSTI. Can. J. Chem. 53,628 (1975). The ionization and thermal decomposition of tungsten n-cyclopentadienyl tricarbonyl dimer [WC,H,(CO),12 was investigated using a mass spectrometer fitted with single and double cell molecular flow inlet systems. The electron impact mass spectrum and appearance potentials for the principle ions in the spectrum have been measured and recorded. The enthalpy change for the dissociation

A fast flow reactor sampled by a TOF mass spectrometer with a molecular beam inlet system

A differentially pumped, double cone molecular beam inlet system on a TOF mass spectrometer for sampling a typical, fast flow reaction vessel is described. By using the diffusion flame technique limitations arising from heterogeneous reactions, reactant mixing times, and viscous flow profiles are minimized. Calibrations have been made to determine the operating range and sensitivity of the apparatus.