An comparative experimental investigation of the helical baffles heat exchenger and the natured heat exchanger has leen finished for the water system. The approximate model of convection heat transfer coefficient has been reported according to the experimental results.

Based on degraded and approximate model of main steam pressure and linear quadratic optimal control theory, the LQ sub-optimal regulation strategy is presented.

The dynamic model of the linkage is established by Kane’s methods. The approximate model of the linkage with all angular rotation of the links being small is developed using Lagrange’s equation.

It is analysised that the approximate model is applied to describe the translation of both the valve stem and the piston rod and the rotation of one link with comparative accuracy, but not to explain the swing of two other links.

In order to improve predicting precision and increase computation speed of simulation for heat exchanger, a novel method is presented in this paper, in which an approximate integral model is used to simplify the original distributed parameter model and an artificial neural network is combined to reflect the nonlinear relations in the integral model.

On the basis of an approximate model of filtration with drainage washings of a soil layer with a water-impermeable base [1], shown schematically in Fig.

In [1], the present author investigated an approximate model of two-dimensional flow in the case of leaching of soil in the presence of an impermeable layer when the depression curve is replaced by a fixed horizontal boundary.

An approximate model of the flow is constructed and an analytic solution is obtained for the location of the boundary of the multicycle jet.

A brief description is given of the approximate model for the calculation of temperature fields, which simplifies the processing of experimental data

Theoretical models of heat transfer by radiation through a vapor gap under conditions of film boiling of liquid are treated, namely, a general wave model for a gap of arbitrary thickness and an approximate model of geometrical optics.

. In this paper a theoretical calculation method of one-side cooling of flattened tube welded on a wall was obtained by calculation of cooling elements. The wall surface temperature can be calculated, the factors that effects the wall surface temperature were revealed, and how these factors effect on the wall surface temperature was showed. All of these provide a base of the engineering design. The experimental results were also reported and compared with the theoretical calculations. And then some of suggestion...

. In this paper a theoretical calculation method of one-side cooling of flattened tube welded on a wall was obtained by calculation of cooling elements. The wall surface temperature can be calculated, the factors that effects the wall surface temperature were revealed, and how these factors effect on the wall surface temperature was showed. All of these provide a base of the engineering design. The experimental results were also reported and compared with the theoretical calculations. And then some of suggestion about one-side cooling of flattened tube welded on a wall were proposed.

A new method of modeling distributed parameter turbulent pipes by using modal approximation methodology was presented.Two kinds of modal approximation models for both hydraulic and adiabatic pneumatic turbulent pipes-the I R C and effective laminar flow modal approximation models were developed.Corroboration of models was given by simulated results of a single pipe after valve closure.The calculated results show a good agreement with those using method of characteristics including frequency dependent friction...

A new method of modeling distributed parameter turbulent pipes by using modal approximation methodology was presented.Two kinds of modal approximation models for both hydraulic and adiabatic pneumatic turbulent pipes-the I R C and effective laminar flow modal approximation models were developed.Corroboration of models was given by simulated results of a single pipe after valve closure.The calculated results show a good agreement with those using method of characteristics including frequency dependent friction

An comparative experimental investigation of the helical baffles heat exchenger and the natured heat exchanger has leen finished for the water system. The approximate model of convection heat transfer coefficient has been reported according to the experimental results. The convection heat transfer coefficient in unit pressure drop of the helical baffles heat exchanger is 2.4 times of the natural heat exchanger. This indicates that the helical baffles heat exchanger is a more reasonable new model heat exchanger...

An comparative experimental investigation of the helical baffles heat exchenger and the natured heat exchanger has leen finished for the water system. The approximate model of convection heat transfer coefficient has been reported according to the experimental results. The convection heat transfer coefficient in unit pressure drop of the helical baffles heat exchanger is 2.4 times of the natural heat exchanger. This indicates that the helical baffles heat exchanger is a more reasonable new model heat exchanger and has a wide deueloping and appling prospect.