In recent years, while demand for heat energy is high in the industrial field, there is a strong need to improve the efficiency of conversion to heat power and other forms of heat energy for processes with low utilization efficiency and the release of surplus heat such as steam that has value in actual factory and other processes. We have proposed the introduction of heat pump technology as a solution to this need. By efficiently raising the temperature of waste heat to a reusable level and by introducing heat pumps to processes with low utilization efficiency, it is expected that significant energy-saving efficiency can be achieved for the entire process. On the other hand, it is necessary to determine the effect of introducing heat pumps based on the annual operation plan of the process in advance, but it is difficult to analyze this effect experimentally. For this reason, it is effective to establish a method to analyze the effect of introducing heat pumps relatively easily by introducing mathematical analysis. In this study, we report a simulation technology to clarify the installation effect of industrial heat pumps by establishing a versatile analysis logic that can easily analyze the annual installation effect of heat pumps consisting of various refrigerants and cycles.

The emulator-type load-based testing methodology is proposed for evaluating the actual performance of air conditioners. The methodology consists of a software that can arbitrarily simulate the dynamic modulation of the building side load-environment, and a testing facility for the real-time measurement of the system performance based on the air-enthalpy method. This paper investigates repeatability and reproducibility of the results obtained from this testing methodology. Round-robin tests were conducted for the same air conditioner within three different testing facilities. The reproducibility level of the corresponding test results demonstrated a deviation within 5%. On the other hand, it was pointed out that the followability of the temperature of the equipment could have a significant influence on the control response of the air conditioner, and as a result, on the level of reproducibility of the test results.

The powder type activated carbon MSC-30 was adopted to analyze the adsorption characteristics of the working pairs utilizing a low Global Warming Potential(GWP) freon refrigerant in this study. The MSC-30 has a larger specific surface area than silica gel which has been widely used as an adsorbent since it is expected to be able to obtain a larger adsorption amount. The low GWP freon refrigerant R 1233zd (E) was selected as an adsorbent in this study, and it is compared with R 1234yf which is the same GWP refrigerant. It was observed that R 1233zd(E) showed a higher adsorbed quantity and a faster adsorption speed than R 1234yf. The isosteric heat of adsorption was predicted taking into account the volume change in the adsorbed phase, it was observed to be approximately the same for both working pairs. These kinds of fundamental information on adsorption working pairs can be considered useful information to utilize activated carbon for the collection, separation, and regeneration of freon refrigerant.

In this research, we focused on the latent heat emulsion to investigate the creation of phase-change cold storage material that maintains fluidity below 0 ℃. The D-phase emulsification method was used to generate the emulsion. And it was generated by using an aqueous solution of ethylene glycol as a dispersion medium and dodecane as a phase change material. The experimental results showed that a fine emulsion was generated by using polyoxyethylene (20) sorbitan monooleate and sorbitan monooleate as surfactants. The average particle diameter of the sample was approximately 0.24 μm. Additionally, from an evaluation experiment using the sample, it was ascertained that the sample could maintain emulsified state for 90 days and it could remain fluid even when the phase change material in the sample was solidified. Moreover, it was revealed that the sample had approximately 60 mJ/mg enthalpy of fusion from the measurement result of a differential scanning calorimeter.

Different types of refrigerator have various partial load performance in terms of fuel or electricity consumption. It is not clear what operation is effective to reduce input energy when different types of refrigerator are combined because the total performance depends on the characteristics of partial load. The objective of this study is to derive the optimal solutions theoretically under the objective function minimizing input when two types of refrigerator with different partial load performance are involved to provide cooling in single time period. The results indicate the conditions where two types work together or one of them is advantageous. Furthermore, assuming quadratic functions of partial load performance, this study also reveals mathematical expression of the competitiveness in terms of the parameters of the quadratic function. Based on the theoretical solutions, a numerical example is also shown comparing the competitiveness of compression chillers and an absorption chiller.