The paper examines the underlying science determining the performance of hybrid engines. It scrutinizes a full range of orthodox gasoline engine performance data, drawn from two sources, and how it would be modified by hybrid gasoline vehicle engine operation. The most significant change would be the elimination of the negative consequences of urban congestion, stop-start, and engine driving, in favour of a hybrid electric motor drive. At intermediate speeds there can be other instances where electric motors might give a more efficient drive than an engine. Hybrid operation is scrutinised and the electrical losses estimated. There also remains scope for improvements in engine combustion.
This contribution aims to appraise, analyze and evaluate the literature relating to the interaction of electromagnetic fields (EMF) with matter and the resulting thermal effects. This relates to the wanted thermal effects via the application of fields as well as those uninvited resulting from exposure to the field. In the paper, the most popular EMF heating technologies are analyzed. This involves on the one hand high frequency induction heating (HFIH) and on the other hand microwave heating (MWH), including microwave ovens and hyperthermia medical treatment. Then, the problem of EMF exposure is examined and the resulting biological thermal effects are illuminated. Thus, the two most common cases of wireless EMF devices, namely digital communication tools and inductive power transfer appliances are analyzed and evaluated. The last part of the paper concerns the determination of the different thermal effects, which are studied and discussed, by considering the governing EMF and heat transfer (or bio heat) equations and their solution methodologies.
The purpose of this work is to present the model of a Parabolic Trough Solar Collector (PTC) using the Finite Element Method to predict the thermal behavior of the working fluid along the collector receiver tube. The thermal efficiency is estimated based on the governing equations involved in the heat transfer processes. To validate the model results, a thermal simulation of the fluid was performed using Solidworks software. The maximum error obtained from the comparison of the modeling with the simulation was 7.6% at a flow rate of 1 L/min. According to the results obtained from the statistical errors, the method can effectively predict the fluid temperature at high flow rates. The developed model can be useful as a design tool, in the optimization of the time spent in the simulations generated by the software and in the minimization of the manufacturing costs related to Parabolic Trough Solar Collectors.
Banana macropropagation in a thermal chamber is an economical technology, effective as a phytosanitary cleaning method, and efficient to enhance seedling production. The objective of this work was to evaluate the effects of corm size (CS) and benzylaminopurine (BAP) on plantain cv. Barraganete seedling proliferation in two propagation environments (PE). The treatments consisted of two levels of BAP (with and without BAP), three CS (2 ± 0.5, 4 ± 0.5 and 6 ± 0.5 kg) and two PE (thermal chamber and raised bed). The variables evaluated were sprouting time (days), multiplication rate (MT) per unit (seedlings per corm) and area (seedlings per m2). Sprouting time was significantly influenced (p < 0.05) by the PE, where the thermal chamber advanced shoot emergence by 12 days, with respect to the raised bed. MT of seedlings per corm and m2, were significantly influenced (p < 0.05) by BAP × AP and TC × AP interactions, where the highest seedling production per corm occurred inside thermal chamber with BAP and 6 ± 0.5 kg corms, while seedling production per m2 was higher with 2 ± 0.5 kg corms under the same thermal chamber conditions and with BAP. The main effects results reported that with BAP there were 30 and 31% increases in MT per corm and per m2, respectively, relative to the treatment without BAP. Within the thermal chamber the MT per corm and per m2 increased by 44% relative to the raised bed. Regarding the effect of CS, larger corms achieved higher individual MT, while smaller corms achieved higher MT per area. The use of a thermal chamber and BAP is recommended for mass production of banana seedlings through macropropagation.
The CO2 heat pump air conditioning system of new energy vehicle is designed, and the vehicle model of CO2 heat pump module and heat management system is established based on KULI simulation. The effects of refrigerant charge, running time and compressor speed on the heat pump air conditioning system is studied, and the energy consumption is compared with the PTC heating system and the CO2 heat pump air conditioning system without waste heat recovery. The results show that the optimal charge for full-service operation is 750 g; increasing the compressor speed can increase the cooling capacity, so that the refrigerant temperature in the passenger compartment and battery inlet can quickly reach the appropriate temperature, but the COP<sub>h</sub>, COP<sub>c</sub> are reduced by 2.5% and 1.8% respectively. By comparing it with PTC heating and CO2 heat pump air conditioning systems without waste heat recovery, it is found that the energy consumption of this system is only for the PTC heating systems 42.5%, without waste heat recovery carbon dioxide heat pump air conditioning system of 86.6%. It greatly saves energy, but also increased the waste heat recovery function, so that the system supply air temperature increased by 26%, improve passenger cabin comfort. This provides a reference for the future experimental research of CO2 heat pump air conditioning and heat management system.
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