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In order to improve the performance of refrigerated display cabinet, decrease the food temperature, improve the uniformity of food temperature and restrain the temperature fluctuation during the defrosting time, a new kind of composite shelf is designed for the food vertical open refrigerated display cabinet (VORDC), which is based on the heat pipe technology and the cool storage characteristics of phase change materials (PCMs) among the heat pipes. Experimental results show that the novel composite shelf can enhance the heat transfer between food and shelf, reduce the core temperature of food, decrease temperature fluctuation in defrosting process and reduce the temperature difference along height, width and depth direction. Compared with the normal shelf, the temperature differences of food packages on both sides of the composite shelves (RT3, RT4 and RT5) are reduced by 40%, 80% and 40%, respectively. The average temperature of food packages is reduced by 13.7–32% and the temperature fluctuation of food packages is reduced by 53.3–83.3% during defrosting. For these kinds of composite shelves, the temperature of food packages of RT4 composite shelf is lowest, and the average temperature of food packages at each layers and rows are controlled in 5 °C. This novel composite shelve can effectively reduce the temperature rise during defrosting, and improve the performance of VORDC obviously.

This paper focuses on improving the performance of the vertical open refrigerated display cabinets (VORDC) by optimizing the structure of deflector, which is affected by inlet velocity and velocity distribution of air curtains. The results show that the temperature of products located at the front and at the rear reduces as the increases of inlet velocity of air curtains. The increase of the inlet velocity of air curtains can strengthen the disturbance inside the VORDC, and also decrease the temperature of products inside the VORDC; the increase of the outer velocity of air curtain will exacerbate the disturbance outside the VORDC and decrease air curtain’s performance. The present study can provide a theoretical foundation for the design of VORDC.

A multi-scale approach has been formulated in a previous work. The influence of HVAC system in supermarket on the performance of vertical open refrigerated display cabinet (VORDC) is considered. The influence is evaluated by varying the supply air temperature and velocity at the diffusers of HVAC. The computational results show that there is a direct interaction between the HVAC system and VORDC in supermarket. When the supply air temperature of HVAC system decreases from 19 °C to 16 °C, the electricity energy input in VORDC system decreases by 6.36%, and the highest products temperature is reduced by 0.18 °C. When the diffuser supply air velocity of HVAC system increases from 2.0 m/s to 3.5 m/s, the energy input in VORDC system decreases by 23.4%, and the highest product temperature reduces by 0.4 °C.

In this paper, the effect of the back panel structure on the performance of fluid flow and heat transfer of vertical open refrigerated display cabinets (VORDC) is presented by experiments and numerical simulation. Experimental tests are performed to validate the accuracy of numerical predictions. The characteristics of heat transfer and fluid flow of VORDC are investigated at the different locations of the perforations of back panel at the same porosity and the different flow ratios between back panel and air curtain at different porosities. By comparing numerical results with experimental results, the predictive abilities of the computational model have been revealed. Further computational results have also shown that less than 3% porosities can provide a better performance in the VORDC; the location of perforations has a minor influence on the temperature distribution of products. Furthermore, the suitable porosities in the back panel among the shelves are more likely to improve the uniformity of products temperature in the VORDC. As a result, the overall uniformity of product temperature inside the refrigerated display cabinet and the maximum deviation values of product temperature have been improve to 41% and 49%, respectively. The present study can provide the theoretical guide for the design of the narrow VORDC.

The numerical solution of the convection–diffusion equation represents a very important issue in many numerical methods that need some artificial methods to obtain stable and accurate solutions. In this article, a meshless method based on the local Petrov–Galerkin method is applied to solve this equation. The essential boundary condition is enforced by the transformation method, and the MLS method is used for the interpolation schemes. The streamline upwind Petrov–Galerkin (SUPG) scheme is developed to employ on the present meshless method to overcome the influence of false diffusion. In order to validate the stability and accuracy of the present method, the model is used to solve two different cases and the results of the present method are compared with the results of the upwind scheme of the MLPG method and the high order upwind scheme (QUICK) of the finite volume method. The computational results show that fairly accurate solutions can be obtained for high Peclet number and the SUPG scheme can very well eliminate the influence of false diffusion.

High-bay depot plays an important role in the storage industry. Due to large and high space of high-bay depot, it is difficult to make temperature distribution uniform, which will influence the storage time of raw materials. In this paper, the aim is to find the reasonable air supply and energy-saving method; a supply-air method of high-bay depot is investigated as an example. The results show the radius and spacing of the supply-air inlet have great influence on temperature distribution. The temperature nonuniformity coefficient of summer is smaller than that of winter. The investigated results can provide a theoretical reference for the high-bay depot design and economic operation.

The paper presents a novel energy efficient routing scheme for photonic network on chip (PNoC) based on the microresonator which takes the insertion loss and the path-setup latency into consideration in order to design a high performance per watt multi-processors. The path-setup latency is a major contributor to the whole system's latency that has something to do with queuing. And insertion loss which has impact on power consumption is closely related to the number of micro-resonators in on state. To solve the multi-objective optimization problem, we design a straight line first heuristic routing scheme. The goal of this routing scheme is to reduce the path-setup latency and insertion loss. Simulation results show that this scheme can low the latency with lower the insertion loss as little as possible.

Ultralow-latency and less power consumption have become necessary in multi-processor interconnection network on chip, photonic interconnection as a solution to meet above requirement, provides high performance interconnection on chip. But the photonic network on chip architecture design and performance is limited because photonic interconnection hasn't buffer, photonic network architecture must be designed to relieve this limitation. In this paper, we present a multi-channel photonic network on chip architecture employing deflection routing, optical data packets can inject/eject from processor core by four channels at the same time. Simulation result shows this network architecture has 60% latency decrease compared to generic photonic network on chip, and the photonic network architecture is only consume 7% power of the electronic interconnection network on chip with the same scale.

This paper presents a reconfigurable Photonic Network on Chip architecture and evaluates its ultra-low latency potential. The latency performance simulation shows a 50% decrease compared to static Photonic Network on Chip.

In this paper, the Meshless Local Petrov-Galerkin (MLPG) method is applied to compute convection-dominated flow problems. The results of the MLPG method are compared with the results of the finite volume method. The results show that the first-order upwind (FUD) scheme exhibits the false diffusion at a larger-Peclet number; the QUICK scheme and the MLPG method can obtain much closed solutions; but they have small overshoots produced at larger-Peclet number. The results also indicate that the MLPG method is a highly effective and accurate numerical method to deal with convection-dominated flow problems and can eliminate the effect of the false diffusion.

A generation algorithm is used to optimize a tunable optical wavelength selection switch (WSS) which is based on a cascaded silicon microring resonator. This method can help us find the optimal inter-ring coupling coefficients which can lead to smaller ripple and better wavelength selectivity over a predefined pass band range. In this paper, we validate this method by a real design and report the results of several, such GA-based WSS optimization. The results show that the GA method performs well even under the limit of physical properties of a silicon ring resonator.