design and development of aircraft systems 2nd edition

... usefulness of a CAD system However, because of the complexity of typical thermal systems and processes, such CAD systems are often limited to the design of relatively simple systems and equipment ... important in the design of FIGURE 2.33 Range of thermal conductivity k for a variety of materials under normal temperature and pressure 110 Design and Optimization of Thermal Systems thermal systems ... storage of data and design information, an interactive graphics terminal, and a plotter for hard copy of the numerical results 98 Design and Optimization of Thermal Systems The computer software codes

Ngày tải lên: 06/08/2014, 15:20

... Further details on the analysis and design of such heat exchangers are discussed in Chapter 152 Design and Optimization of Thermal Systems Example 3.3 In the design of a hot water storage system, ... the solution of the mathematical equations and to study the behavior and characteristics of the system This is the process of simulation of the system under a variety of operating and design conditions ... equations and boundary 170 Design and Optimization of Thermal Systems TABLE 3.1 Commonly Used Dimensionless Groups in Fluid Mechanics and Heat and Mass Transfer Parameter Definition VL Ratio of Effects

Ngày tải lên: 06/08/2014, 15:20

... power-law dependence of Q on the two independent variables D and p  19 4 Design and Optimization of Thermal Systems Solution The variation of Q with D and p may be written ... some of the complexities of practical thermal systems and the derivation of governing dimensionless parameters. The results indicate typical outputs obtained and their relevance to system design. ... /A and k s /k. These 174 Design and Optimization of Thermal Systems may be varied in the simulation of the given system to determine the effect of materials used and the operating conditions.

Ngày tải lên: 06/08/2014, 15:20

... range of 0 – 3 m/s. If the signal E is measured as 2, 9, 24, and 47 volts at the velocity V of 0, 1, 2, and 3 m/s, respectively:     FIGURE P3.35 206 Design and Optimization of Thermal Systems ... coupled set of equations to determine the behavior and characteristics of the system for wide ranges of design variables and operating conditions Because of the coupled nature of these ... necessary to understand the algorithm adopted by the available software so 212 Design and Optimization of Thermal Systems. .. Thermal Systems well as a variety of operating conditions

Ngày tải lên: 06/08/2014, 15:20

... value of 10 –4 was found to be adequate The relaxation factor was varied from 1.0 to 2.0 and the number of iterations needed 238 Design and Optimization of Thermal Systems 600 = 10–4 Number of iterations ... triangular elements 244 Design and Optimization of Thermal Systems commonly used for thermal processes and systems is Galerkin’s method (Jaluria and Torrance, 2003) The ultimate result of applying the ... a first-order ODE and thus of higher-order equations and systems of ODEs Two main classes of methods are Runge-Kutta methods Predictor-corrector methods Numerical Modeling and Simulation 229

Ngày tải lên: 06/08/2014, 15:20

... effects of different design variables for optimization Improve or modify existing systems Investigate sensitivity of the design to different variables Evaluation of Design Evaluation of different designs ... this simulation is not often used in the design of thermal systems Electrical circuits used to simulate fluid-flow systems, consisting of pipes, fittings, valves, and pumps, and conduction heat ... modeling and tests, as well as material properties, form part of the overall model 254 Design and Optimization of Thermal Systems and are assumed to be known These may be available in the form of data

Ngày tải lên: 06/08/2014, 15:20

... of the simulated system Comparison of results from simulation of simpler systems with available analytical and experimental results 284 Design and Optimization of Thermal Systems Comparison of ... system; variation of operating conditions to consider design and off -design conditions; and investigation of system behavior for different design parameters Therefore, the validation of the simulation ... importance and uses of simulation are presented Of particular interest is the use of simulation to evaluate different designs and for optimization of the system However, the application of simulation

Ngày tải lên: 06/08/2014, 15:20

... Formulation of the design problem Conceptual design Initial design Modeling of the system Simulation of the system Evaluation of the design Selection of an acceptable design Optimization of the design ... circuitry 304 Design and Optimization of Thermal Systems Library of Previous Designs Any industry involved with the design of systems and equipment would generally develop many successful designs over ... modeling and simulation, and evaluation of the design for its acceptability are based on the initial design The initial, starting design affects the convergence of the iterative design process and often

Ngày tải lên: 06/08/2014, 15:20

... initial design, modeling, and simulation to design evaluation, redesign, and convergence to an acceptable design It has also been seen that thermal systems arise in many diverse Acceptable Design of ... temperature of the fluid surrounding the cord, R is the radius of the core-mandrel assembly and subscript i refers to the mandrel and the contact surface between the cord and the mandrel If Ts ... convection and constant heat flux input qs, with qsR/k 5.0 328 Design and Optimization of Thermal Systems Heaters Mandrel and cord Entrance Air flow Fan Exit FIGURE 5.18 A possible conceptual design

Ngày tải lên: 06/08/2014, 15:20

... thermal systems and to different problems Some of these areas and problems are considered again in later chapters with respect to optimization 5.4.7 DESIGN OF COMPONENTS VERSUS DESIGN OF SYSTEMS ... constraint of 100 m is satisfied 350 Design and Optimization of Thermal Systems It is seen here that once an acceptable design is obtained, other designs can easily be generated by varying the design ... treatment and discussion have been largely directed at systems Not much has been said about the design of components, even though each system obviously consists of a number of components and the design

Ngày tải lên: 06/08/2014, 15:20

... use of hollow mandrels is suggested as an improvement in the design Consider this change and determine the effect on the simulation and the design However, the thickness of the wall of the mandrel ... such systems The design process is fundamentally the same for large and small systems and the basic approach presented in this and earlier chapters can easily be applied to a wide range of systems ... discussed 374 Design and Optimization of Thermal Systems In order to illustrate the coupling of the different aspects and steps involved in the design process, several important areas of application

Ngày tải lên: 06/08/2014, 15:20

... involves the relevance of economic considerations in the design of thermal systems Therefore, calculations of present and future worth of lumped amounts as well as of a series of uniform or increasing ... adjustment of design variables for the final design In most cases, the output or performance is balanced against the cost 420 Design and Optimization of Thermal Systems so that an optimal design ... basis of the present worth of 414 Design and Optimization of Thermal Systems all costs Then, initial cost, salvage value, and maintenance costs are all brought to the common time frame of the

Ngày tải lên: 06/08/2014, 15:20

... followed by the use of the model in the design and development of new products and also in the improvement of existing designs (Box and Draper, 1987) RSM is used when only a small number of computational ... acceptable designs may be 442 Design and Optimization of Thermal Systems generated by changing the variables In either case, a number of workable designs are obtained, and the optimal design is ... are 434 Design and Optimization of Thermal Systems U Global maximum x1 Acceptable design domain FIGURE 7.2 Global maximum of the objective function U in an acceptable design domain of the design

Ngày tải lên: 06/08/2014, 15:21

... with thermal systems, an important consideration is the second law of thermodynamics, which brings in the concepts of entropy and maximum 456 Design and Optimization of Thermal Systems useful ... analysis and the use of the second law of thermodynamics for the optimization of thermal systems; see, for instance, Bejan (1982, 1995) and Bejan et al (1996) Similar to the conservation of mass and ... overall design and optimization of thermal systems 7.5.1 CHOICE OF VARIABLES FOR OPTIMIZATION Several independent variables are generally encountered in the design of a thermal system A workable design

Ngày tải lên: 06/08/2014, 15:21

... derivatives tF/tx and tF/ty as the 478 Design and Optimization of Thermal Systems two components in these directions. For example, if the temperature T in a region is given as a function of x and y, the ... c 4 φ = c 2 φ = c 1 dφ = 0 dx x 480 Design and Optimization of Thermal Systems understanding the basic characteristics of the Lagrange multiplier method and for developing other optimization ... the system, we would 474 Design and Optimization of Thermal Systems seek the global extremum, which is usually unique and represents the largest or smallest value of the objective function.

Ngày tải lên: 06/08/2014, 15:21

... 500 Design and Optimization of Thermal Systems 8.5.4 SOME PRACTICAL CONSIDERATIONS In the preceding discussion, we assumed that an optimum of the objective function exists in the design domain and ... insulation, and pipe costs Here, D is the diameter of the pipe and x is the thickness of insulation, as shown in Figure P8.1 Find the values of D and x that result in minimum cost 8.2 A manufacturer of ... approximation, the cost of making a can consists of the cost of the metal plus the cost of welding the longitudinal seam and the top and bottom The can may have any diameter D and length L, for a

Ngày tải lên: 06/08/2014, 15:21

... and Vahid, F., Specification and design of embedded hardware-software systems, IEEE Design & Test of Computers, pp. 53-67, Spring 1995. [14] DeBardelaben, J. and Madisetti, V., Hardware/software ... consumed bandwidth of transmitting packets, bw passing is the consumed bandwidth of passing packets, bw echo is the consumed bandwidth of echo packets, and BW idle is the consumed bandwidth of idle ... executable form and through successive stages of design refinement, and ends with a detailed hardware design. VHDL models are used throughout the design process to both document the design stages and provide...

Ngày tải lên: 25/12/2013, 06:16

... advantages and disadvantages, and it is the designers task to find a suitable compromise that best fits the task at hand. Table 2.5 sum- marizes the frequency- and time-domain characteristics of these ... nearly flat in the passband and rolls off smoothly and monotonically. In addition, it has virtually no ripple in either the passband or the stopband. For these reasons, many designers regard the ... true friend, and a most compassionate human being. —David ffirs.qxd 11/22/2004 9:46 AM Page v 1 1 Design and Development of Medical Electronic Instrumentation By David Prutchi and Michael Norris ISBN...

Ngày tải lên: 29/03/2014, 11:20

... (1.8.5) can provide an estimate of H 0 , together with a strong confirmation of the validity of the Hubble law and, therefore, of the Cosmological Principle. Another test of this principle is the so-called ... apparent magnitude of a source and its redshift and the N(> l)–z relationship between the number of sources of a given type with appar- ent luminosity greater than some limit l and redshift less ... theories of structure formation using statistical properties of galaxy clustering, the fluctuations of the cosmic microwave background, galaxy-peculiar motions and observations of galaxy evo- lution and...

Ngày tải lên: 03/06/2014, 01:49