•Isopropanol-butanol-ethanol (IBE) was used to improve spray evaporation of diesel.•Spray development process was tested via optical method in a constant volume chamber.•Liquid spray penetration was ...shortened significantly after blending IBE into diesel.•The break-up time of fuel blends always earlier than that of pure diesel noticeably.
As an intermediate fermentation product of butanol, isopropanol-butanol-ethanol (IBE) can be used as an alternative fuel for diesel directly to reduce the separation and purification costs during the butanol fermentation process. However, how the properties of IBE affect the spray evaporation characteristics of diesel is rarely studied. In this regard, IBE was blended into diesel at various volumetric ratios and then tested in a constant volume chamber using Mie scattering method. The experimental results show that after blending IBE into diesel, the spray evaporation characteristics improve noticeably. The more IBE blended into diesel, the shorter liquid spray penetration and smaller spray area are. However, the reduction of the liquid spray penetration and spray area are not linear, they exhibit a huge drop when the IBE to diesel ratio increases from 60% to 80% in volume. With more IBE blended into diesel, the time for the spray to reach the stable stage decreases. Results also show that the ambient temperature has great effects on both the spray evaporation of pure diesel and IBE/diesel blends. As the ambient temperature rises, their spray jets become smaller, and the corresponding liquid spray penetration become shorter. That means elevate the ambient temperature can further improve the spray evaporation of IBE/diesel blends.
•Isopropanol-butanol-ethanol (IBE) mixtures with different component ratio were tested.•Isopropanol in IBE plays a dominate role on improving the spray combustion characteristics.•The larger volume ...of isopropanol in IBE, the shorter the liquid penetration.•IBE/diesel blends containing more isopropanol present noticeably lower natural luminosity.•Increasing the ratio of isopropanol in IBE is capable of reduce the soot formation.
Isopropanol-butanol-ethanol (IBE) is a clean and renewable biofuel, but its component ratio effects on the spray combustion process of diesel have not been reported to date. In this study, IBE mixtures with different component ratios (6:3:1, 3:6:1 and 0:10:0) were separately blended into diesel at the volumetric ratio of 20% and then tested in a constant volume chamber. The experimental results show that isopropanol in IBE plays leading role on the spray combustion characteristics of IBE/diesel blends; the more isopropanol in the IBE blend, the shorter the liquid penetration is. Furthermore, the IBE/diesel blends containing more isopropanol always exhibit a long ignition delay but a short combustion duration. Results also show that regardless of whatever type of IBE/diesel blends, the flame lift-off length (FLOL) prolongs and the spatial integrated natural flame luminosity (SINL) reduces. However, the magnitudes of reduction of the SINL for the IBE/diesel blends vary with the component ratio of IBE. The IBE/diesel blends containing more isopropanol always present a noticeably lower SINL. Compared with pure diesel, the fuel blends containing more isopropanol are capable of reducing the time integrated natural luminosity (TINL) almost by half in most test conditions. That is to say, increasing isopropanol ratio in IBE can reduce the soot formation of IBE/diesel blends but the increase of the butanol ratio has an opposing trend.
•Water containing isopropanol-n-butanol-ethanol (IBE) is used as an alternative fuel of SI engine.•Water containing IBE-gasoline blends with various IBE and water concentration are ...tested.•Combustion, performance and emissions characteristics are investigated.•Water containing IBE has a potential to improve energy efficiency and reduce pollutant emissions.
Bio-n-butanol has attracted great attention as a potential alternative fuel in internal combustion engines (ICEs) due to its favorable physicochemical properties. However, the main issue impeding the use of bio-butanol in ICEs is its relatively high cost and energy consumption of dehydration and recovery processes in acetone-n-butanol-ethanol (ABE) or isopropanol-n-butanol-ethanol (IBE) fermentation technologies. Some researchers have proposed to use intermediate fermentation product, i.e. water-containing ABE or IBE, for clean combustion. Therefore, an experimental evaluation of spark-ignition (SI) engine fueled with water-containing IBE-gasoline blends was carried out in this study. Effects of IBE and water addition on combustion, performance, and emissions characteristics were first investigated at stoichiometric condition. Then, a “drop-in” fuel test was performed, i.e. IBE9W1 (9 vol.% IBE, 1 vol.% water and 90 vol.% gasoline) was compared with pure gasoline under various engine loads (3 and 5 bar BMEP) and equivalence ratios (Φ = 0.83–1.25). It was found that IBE9W1 showed a higher brake thermal efficiency, and a lower CO, NOx and BTX (benzene, toluene and xylene) emissions. The results indicate that water-containing IBE could be used as a fuel candidate in SI engine due to its eco-friendly production method and potential to improve energy efficiency and reduce emission pollutants.
The last decades have seen a renewed interest in the study of argumentation in archaeology, particularly in response to the overproduction of weak and unreliable interpretations and explanations. ...Concurrently, recent appeals for scientific transparency and efficiency in the management of archaeological information in digital form have stressed the necessity of explicitly showing the processes followed. A growing body of literature has identified inference to the best explanation (IBE) as the most adequate way of interpreting archaeological data, although it has quietly existed for over a century. Despite this, the investigation of IBE-based models for recording archaeological reasoning remains a largely under-researched topic. The author concludes with a novel IBE-based model for recording archaeological argumentation.
This study is aimed to investigate the performance, combustion, and emissions of a common-rail diesel engine fueled with IBE and diesel blends. Two blends of IBE and diesel fuel, denoted as IBE15 ...(15% IBE and 85% diesel in volume) and IBE30 (30% IBE and 70% diesel in volume), were tested under different injection strategies. The experimental results show that compared with single injection, the in-cylinder pressure and heat release rate curves (HRR) for all the tested fuels under double injection cases are less severe. That is to say, a pilot injection can reduce knocking combustion and ringing intensity when blending a high ratio of IBE into diesel. Furthermore, double injection is helpful in improving both engine performance and economy for all the tested fuels, especially for IBE30. For almost all the tested conditions, both IBE15 and IBE30 present a potential to reduce soot emissions but increase NOx emissions. A pilot injection is favorable to reduce NOx emissions but causes the soot emissions to increase. Results also show that the flame lift-off length of IBE30 is much longer than that of pure diesel. This feature may result in better air-fuel mixing, which then contributes to reduce soot emissions.
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•Characters of IBE and diesel blends at different injection strategies were studied.•Injection strategy affects the combustion process of IBE and diesel blends greatly.•Maximum pressure and HRR are obviously reduced when adopting a pilot injection.•Both engine performance and economy are improved under double injection conditions.•Double injection is helpful to reduce NOx emissions while increase soot emissions.
•The waste heat of extraction - extractive distillation is recovered by heat integration and organic Rankine cycles.•Compared with the heat-integrated process, organic Rankine cycle assisted process ...save 8.88% total annual cost.•The control scheme of organic Rankine cycle assisted extraction - extractive distillation process shows good robustness.
The high-purity isopropanol butanol ethanol (IBE) mixture is a highly efficient gasoline additive that can be directly used without further separation. The product of isopropanol-butanol-ethanol fermentation contains a large amount of water, and a large amount of energy will be consumed in the purification process. In this paper, the separation IBE process is systematically studied from the aspects of process optimization, energy recovery and process control. The operation parameters of extraction combined with extractive distillation (E-ED) are optimized by a multi-objective genetic algorithm. Then, the pinch point technique is used to analyze the energy usage of the optimized process, and the maximum heat recovery heat integration scheme is obtained. Compared with the optimized process, the low pressure steam consumption of the heat integration process is reduced by 100%, the cooling water consumption is saved by 58.80%, and the TAC is reduced by 35.95%. In view of massive waste heat in the heat integration of the extraction combined with extractive distillation (E-ED-HI) process, a new configuration combining the E-ED-HI and organic Rankine cycle (E-ED-HI-ORC) is further proposed. The organic Rankine cycle using R600a can further reduce TAC by 8.88% based on the HI-E-ED process. Finally, the control scheme of E-ED process is proposed. The performance of the control scheme is examined with ±10% disturbance of the feed flow rate and composition change, and the results show that the process of extractive distillation and separation of IBE has good controllability.
Identity-Based Encryption (IBE) which simplifies the public key and certificate management at Public Key Infrastructure (PKI) is an important alternative to public key encryption. However, one of the ...main efficiency drawbacks of IBE is the overhead computation at Private Key Generator (PKG) during user revocation. Efficient revocation has been well studied in traditional PKI setting, but the cumbersome management of certificates is precisely the burden that IBE strives to alleviate. In this paper, aiming at tackling the critical issue of identity revocation, we introduce outsourcing computation into IBE for the first time and propose a revocable IBE scheme in the server-aided setting. Our scheme offloads most of the key generation related operations during key-issuing and key-update processes to a Key Update Cloud Service Provider, leaving only a constant number of simple operations for PKG and users to perform locally. This goal is achieved by utilizing a novel collusion-resistant technique: we employ a hybrid private key for each user, in which an AND gate is involved to connect and bound the identity component and the time component. Furthermore, we propose another construction which is provable secure under the recently formulized Refereed Delegation of Computation model. Finally, we provide extensive experimental results to demonstrate the efficiency of our proposed construction.
In this paper, we describe the first generic construction for multimodal biometric Identity Based Encryption considering two distance measures at the same time. Current protocols for fuzzy/biometric ...IBE are designed either for set overlap or Euclidean distance within unimodal biometrics. However, the similarity measures for biometric templates can be quite different from those considered in theoretical works. For instance, a fingerprint template usually consists of a set of minutiae, and two templates are considered as similar if more than a certain number of minutiae in one template are near distinct minutiae in the other. In this case, the similarity measure has to consider both Euclidean distance and set difference at the same time. Similarly, multimodal systems that are designed to address the limitations of unimodal systems may involve two different traits requiring different distance measures for each modality.
In order to have high recognition rate and thus increased possibility of decryption even in case of white noise (slight perturbation of biometric features), our generic construction is based on two different biometric IBE systems encoding the same message. This way, employment of both distance measures is possible using multiple matchers within multimodal setting and a failure on the decryption of a message encrypted using the first biometric representation, can be compensated with an attempt on the second part of the ciphertext encrypting the same message but using a different representation of the same receiver. Specifically, we combine a fuzzy IBE-type scheme and the recently introduced Distance Based Encryption (DBE) scheme with minimum overhead in terms of public parameters, ciphertext and private key size. For this purpose, we describe an efficient biometric IBE scheme denoted as ordFIBE, which is restricted for biometrics that can be represented as an ordered/grouped set of features. We study the security of ordFIBE both in random oracle model (ROM) and for small universe of attributes in standard model. In ROM, its efficiency is further improved by employing online/offline encryption technique. Next, we instantiate the new construction by combining ordFIBE and the DBE scheme of Guo et al. (2014), which shares the same setup phase, in particular, common public parameters. Finally, we describe a new scheme for set difference metric that partially solves an open problem introduced in Katz et al. (2008).
•The first construction of multimodal biometric IBE designed for two distance measures.•High recognition rate and increased possibility of decryption in case of white noise.•Multiple matchers for Set overlap and Euclidean distance within multimodal setting.•Common public parameters for an efficient two-layer encryption of the same message.
The utilization of isopropanol-butanol-ethanol (IBE) to clean energy effectively mitigated the problems of environmental pollution and sustainable energy regeneration. In order to improve the ...utilization efficiency of ethanol and isopropanol in IBE, a liquid double-layer porous media burner was designed. And the combustion characteristics with different porous pellets and isopropanol ratios were studied. The results indicated that the mole fraction of hydrogen decreased with the increasing pellet diameter, and the lower heating value of syngas reached the highest value of 82.0 MJ/Nm3 when the pellets possessed two holes. Meanwhile, the peak temperature reached the maximum of 1009 K when the water content was 20% due to the sufficient combustion. And the isopropanol was conducive to the improvement of the total energy conversion efficiency. In addition, the yields of hydrogen and carbon monoxide were improved by 23.7% and 30.5% when the velocity increased from 10 to 12 cm/s. These results showed that the combustion of ethanol and isopropanol in porous media burners achieved the sustainable production of hydrogen and efficient utilization of IBE biofuels.
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•Isopropanol and ethanol were combined with porous media for hydrogen production.•Hydrogen production was greatly improved with isopropanol addition than n-propanol.•15% isopropanol and 85% ethanol obtained the energy conversion efficiency of 96.0%.•Increasing the hole number in porous pellet reduced the combustion temperature.
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