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This paper describes thermal capacity and thermal inertia of an underfloor heating system supplied from a heat pump. A MATLAB/SIMULINK based thermal model of the system have been developed and presented with detailed mathematical equations. For this purpose, experimental results and actual measurements are used to model the energy storage and temperatures. The parameters used for the model are temperature,...
Gas pump thermocouple plays a major role in accurate measurement of the kiln temperature and reducing temperature measurement error. How to design and optimize hot cover structure as well as raise temperature measurement precision has become an important issue in researching and developing new temperature measuring equipment. The author uses the FLUENT6.0 software to simulate the suction of thermocouple...
Plate-fin heat sinks have been a successful technology in electronics cooling. Thermal performance of such heat sinks, however, has been driven to improve due to increasing heat generation in modern electronics devices. This paper proposes to introduce short pin fins on surfaces of plate-fin heat sinks to address such challenges. A microfabrication approach based on photolithography and electroplating...
Heat transfer around vertical ground Heat transfer around vertical ground heat exchangers is a common problem for the design and simulation of ground-coupled heat pump (GCHP) systems. A serial of calculation models have been found for ground heat exchangers to predict the temperature distribution of superficial layers, but most of them still take the thermal characteristics of the ground as constant,...
This article analyses the temperature environment of air source heat pump using the air in underground tunnel as cold and heat sources, then models tunnel heat transfer and numerically computes, compares with experiment data and gets the result. It can provide some practically help on tunnel wind cooling technology and tunnel heat transfer calculating.
This paper obtained the changing range of sewage temperature, the inlet and outlet temperatures of the sewage heat exchanger, evaporator and condenser in winter by monitoring the large sewage source heat pump system in Shi Jia-zhuang. By the testing data, the operating performance of the heat pump system was studied. During the heating test, the heat pump system operated steadily and the coefficient...
A desuperheater heat recovery system that includes a reversibly used cooling tower (RUCT) was studied by simulation and field tests in subtropical regions in China. This paper presents the field test of a RUCT heating system using heat pump (RUCTHPS) in winter installed in a test office building, which is located in Changsha, Hunan province, a hot summer and cold winter region in China. Instead of...
Temperature and pressure are important parameters related to energy consumption and safe operation of oil depot. A mathematical model is established from the point of temperature drop and pressure drop during storage and transportation process based on the reasonably simplified physical model of oil depot. Then parameter distributions of each node are obtained by the application of sequential modular...
Ground source Heat Pump(GSHP) is becoming the more and more focus of the world's attention as a HVAC technique of energy saving and environment protection. This paper first introduced the experiment for Ground-Source water/water Heat Pump. The heat transfer model of underground heat exchanger was introduced, and established predication modeling using neural network. From the computer simulation results,...
A honeycomb porous microchannel cooling system for cooling electronics is proposed in this paper. The design, fabrication, and test system configuration of the microchannel heat sink are presented. Experiments were conducted to determine the heat transfer characteristics and cooling performance of this microchannel cooling system under steady single-phase flow of water. In the experiments, a brass...
In the design of ground source heat pump system, for calculating the problems of the capacity of system and the number of ground heat exchanger, etc. The original soil temperature, soil thermal properties, soil average temperature and other basic parameters as the input conditions of the calculation often need to be made certain. On the other hand, contracted with the measured values, because of the...
This article analyses the temperature environment of air source heat pump using the air in underground tunnel as cold and heat sources, then models tunnel heat transfer and numerically computes, compares with experiment data and gets the result. It can provide some practically help on tunnel wind cooling technology and tunnel heat transfer calculating.
The coefficient of performance (COP) is one efficient important evaluating indicator in the urban sewage heat pump system. Based on the engineering thermodynamics principle, the heating operating performance of direct and indirect systems have been analyzed and compared. The results indicate that the actual COP of direct sewage source heat pump system is higher approximately 0.3 than that of indirect...
A water-to-water geothermal heat pump is a suitable technology to exploit heat from low-temperature geothermal sources for high-temperature district heating. A distributed parameter model simulation analysis was conducted for the system using non-azeotropic mixture of R245fa and R152a (0.63/0.37) under the condition that the input temperature and the flow rate of the heat transfer fluids were provided...
At first, the article presented particularly the working theory of the system of ground source heat pump combined with floor radiant heating of capillary tube, the characteristic of soil layers and the arrangement form of capillary tube mat and the floor structure. And then, the specific experimental method was employed to study the ground heat exchanger performance of three wells of 90 m depth, heating...
At first, the article presented particularly the experimental system of floor radiant heating of capillary tube, the arrangement form of capillary tube mat. And then, the experimental method was employed to study heating capacity of capillary tube mat, the characteristic of temperature change on the layer of capillary tube mat, the ceiling surface and indoor air. At same the time, BIN method was adopted...
With the help of LHTS (Latent Heat Thermal Storage) tank to primary Air Conditioning, a fresh air system of solar energy storage with LHTS is presented. In this paper, heat transfer characteristics of the system and Energy-saving optimizing design method for the compounded system were firstly studied. Then the structure of hardware and software were designed for, and the field and remote monitoring...
Maximization utilization of an air conditioning unit is vital for the present energy crisis situation. The objectives of this research are to design and fabricate a portable air conditioning-heat pump unit for produce cool air and warm water. In other words, this unit can provide warm-water as a by product of air-conditioning. It is appropriate for the household section, and some type of commercial...
The paper deals with problematic of renewable energy sources focused mainly on use of sun energy, hydrogen technology and, above all, use of heat pumps for buildings heating. It gives a basic introduction into renewable energy sources and their use in practice. Another part described in details is thermal response test (TRT). This test is instrumental to find out a response of rock massive in which...
Cooling is important to keep the temperatures of the highly integrated silicon electronic devices and power devices e.g. power MOSFET, IGBT. Yamaguchi et al. have proposed a new scheme to cool down the devices by its own current named ldquoself-cooling devicerdquo, in which the cooling process uses Peltier effect. In the proposed scheme, we should use the materials that have high thermal conductivity,...
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