Advanced Materials Research Vols. 516-517

Abstract: In this paper, a local radial point interpolation method is given to obtain the numerical solutions of the coupled equations in velocity and magnetic field for the fully developed magnetohydrodynamic flow through a straight duct of rectangular section with arbitrary wall conductivity. Computations have been carried out for different Hartmann numbers and different wall conductivity. Since the energy equation is uncoupled with velocity and magnetic field for the fully developed magnetohydrodynamic flow, the finite volume method, which is effective on heat transfer problems, is applied to solve the energy equation with the obtained velocity fields.

Abstract: In this study, a performance analysis based on alternative performance criteria has been performed for a reversible Carnot and heat pump cycle, modified for cogeneration, with external irreversibilities. The optimum values of the design parameters of the new cogeneration cycle were determined for different criteria. In this context, the effects of design parameters on the exergetic performance are investigated, and the results are discussed. The obtained results may guide towards a more realistic criterion for actual combine heat pump and cogeneration plants.

Abstract: The characteristics of the WGZ170/9.8-3 pulverized coal boiler were obtained based on cold test，Including the air velocity distribution in tangential firing boiler and the relation between air distribution with opening of each secondary air dampe，The test results had determined that the baffle of blower at around 40% and two parallel draft fan about 45% were relatively appropriate. and the air distribution and opening of each secondary air dampe and balancing the distribution of primary air and second air along the width direction of the boiler hearth were confirmed through test，and the aerodynamic field inside the boiler was investigated based on the tie-floating test．and good aerodynamic field can be obtained after distributing the primary air and second air reasonably，which guarantee the ignition and stable operation of the boiler．

Abstract: Sneak circuit analysis technique is an important analytical tool that can promote the safety and reliability of the circuit control system. It applied to aerospace control engineering widely now. Comparing a thermal system and electric circuit system, the concept and method of sneak path analysis for complex thermal system are proposed by this paper. And the development and application vista of thermal system sneak path analysis and specific implementation are analysed.

Abstract: The carbonate looping process is a promising technology for post-combustion CO₂ capture from power plants.CO₂ capture is performed in a system of two fluidized bed reactors.In this paper, material and energy of the process have been performed using ASPEN PLUS.The present study focuses on energy recovery of CCRs system and the effect of make-up mass flow on circulating solids mass flow, coal feed to the calciner, and CO₂ capture efficiency.

Abstract: Stable analysis of flow and heat transfer in the saturated liquid film of liquid low boiling point gases falling down an inclined heated plate is investigated. Firstly, the boundary value problem of linear stability differential equation (Orr–Sommerfeld equation) on small perturbation is derived representing surface tension by nonlinear relationship on temperature. Then, the expression of the wave velocity is got by solving the boundary value problem of O–S equation using the perturbation method. The effects of the inclined angle and some other factors, such as Reynolds number, wave number, temperature of the plate and the parameter for the physical property, on stability in the saturated liquid film of liquid low boiling point gas N2 are numerically analyzed by MATLAB software. Finally, it is shown and analyzed a new critical Reynolds number which is actually the extension of Yih’s.

Abstract: In this paper, the mathematical model of a horizontal-tube falling film evaporator that used in air condition and refrigeration system was founded. The evaporative tubes of the evaporator were cold and staggered arrangement. The numerical simulation of the intervascular flow of the oil-bearing refrigerant R134a was carried out, under the conditions of varies flow mode and varies structures of distributed equipment. Under the standard condition of air conditioning, the study of the intervascular two-phase flow characters of the horizontal-tube falling film evaporator were analyzed in the last. The research achievements can provide theoretical laws for relief the effects of the intervascular vapor shear stress on the quality of the liquid film formed outside the evaporative tubes. And the conclusions have practical and guide means for the horizontal-tube falling film evaporator design and evaporative tubes arrangement optimization.

Abstract: Thermal analysis has been employed to yield information on the volatility of the biodiesel/petrodiesel since the volatility influences the ignition quality of the fuels in a compression ignition engine. The chemical composition of -10 petrodiesel (-10PD) and soybean biodiesel (SME) was analyzed by gas chromatography-mass spectrometry. The thermal volatilization of biodiesel and its blends was investigated by thermogravimetry and liquid volatile theory. Volatile index was put forward for describing biodiesel/petrodisel volatility. A good correlation model was proposed for calculate the biodiesel/petrodiesel volatility by biodiesel blending ratio. The study showed that -10PD was mainly composed of long chain alkanes: C8–C26. SME was mainly composed of long chain fatty acid methyl esters: C14:0–C24:0, C16:1–C22:1, C18:2 and C18:3. The volatile indexes of SME and -10PD were, respectively, 1.74E-04 and 3.64E-05. The biodiesel fuel was considerably more volatile in comparison to the petrodiesel fuels. The SME/-10PD volatility had relation to SEM blending ratio, it was better with increasing the SME blending ratio.

Abstract: A physical model of a 5A zeolite pellet considering its micro-structure is established. Mathematical models to describe the mass and heat transfer process occurred inside the pellet are proposed. Two adsorption processes, including an isothermal and an adiabatic process are comparatively studied. The N2 adsorption properties on 5A zeolite pellet at different thermal conditions are compared. The effects of adsorption heat on adsorption capacity, adsorption rate and adsorbent equilibrium time are revealed.

Abstract: In view of the characteristics of the preparation of an adhesive process which is lengthy, nonlinear, time-varying, big inertia and pure delay, A Proportional-Integral-Derivative (PID) algorithm is proposed based on the improved particle swarm optimization. Because there are drawbacks in the design of PID controller, an improved particle swarm optimization which takes into account a number of performances is propesed to modified parameters of PID controllers. In which the variation of genetic algorithm is introduced to the standard particle swarm optimization algorithm, which can avoid local maximum points, thus the preferable PID controller parameters are easily obtained. Applying the algorithm to the preparation of an adhesive process, the temperature of polymerizing-kettle can be tracked and controlled. Simulation and factual running shows that the algorithm is effective and has excellent performance.