A Two-Stroke Range Extender Engine for Heavy Duty Battery Electric vehicle applications

Turbo, two-stroke, range extender, BE

Spark ignition engine performance, standard emissions and particulates using GDI, PFI-CNG and DI-CNG systems

Gaseous fuels, e.g., natural gas, biogas, have several advantages over liquid fuels owing to their favorable physical and chemical properties, e.g., lower carbon numbers in the fuel composition and no issues regarding fuel evaporation. The present study investigated compressed natural gas (CNG) port fuel injection (PFI) and direct injection (DI) systems compared to gasoline direct injection (GDI) cases in a spark ignition (SI) naturally aspirated single cylinder engine at stoichiometric conditions. The tests included usual engine working points – from 4.5 bar IMEP to 9 bar IMEP engine load at different engine speeds – from 1500 rpm to 2500 rpm. The main aim was to investigate how gaseous fuels can improve the SI engine efficiency, reduce standard emissions and particulates, and explain the benefits of a natural gas DI system versus standard gas PFI and GDI systems. Analysis of the results showed that the rate of heat release of natural gas was lower than that of gasoline fuel. However, the stable combustion process of DI-CNG gave additional benefits, e.g., increased turbulence in the cylinder, which increased the combustion rate and affected the exhaust gas formation. The highest engine efficiency was achieved with the same natural gas DI system. The highest iSHC, iSCO, iSCO2 and iSNOx emissions reduction achieved at low and part load conditions with DI-CNG compared to GDI combustion. Particulates formation was lower with the gaseous fuel compared to gasoline. Additional benefits of lower particulate numbers among three injection systems were observed with DI-CNG combustion

DI-CNG injector nozzle design influence on SI engine standard emissions and particulates at different injection timings

Compressed natural gas direct injection (DI-CNG) systems in spark ignition (SI) internal combustion engines have shown that it can give several benefits compared to CNG port fuel injection systems. However, the DI-CNG injector nozzle head design and gas jet formation may greatly influence engine exhaust gas emissions and performance. Present experimental study investigated the influence of 7 different nozzle head designs of sprayguided DI-CNG injectors on the combustion process, engine performance, standard emissions, and particulate number (PN) when methane fuel was injected at different injection timings (SOI) and injection pressures (18 bar and 50 bar). The nozzle heads had two main design patterns – heads with small multi holes/orifices and heads with larger crevices (swirl or umbrella spray pattern). Naturally aspirated SI engine tests were conducted at part load (6 bar IMEP) and wide-open throttle (WOT) at 2000 rpm engine speed. The results revealed that the difference between the nozzle heads was small when the fuel was injected at an early stage of the intake stroke (310–350 CAD bTDC) either at part load or high load. However, for late injection timing (130–190 CAD bTDC), the design of the DI-CNG injector nozzle head had a large impact on the combustion stability, standard emissions formation and particulates. Multi-hole nozzle heads showed improved CO2, CO, THC, total PN, and slightly higher NOx emissions compared to nozzle heads with larger crevices. For some of the nozzles, the SOI could be retarded more than for other injector head designs at higher injection pressure whilst still ensuring an acceptable engine performance in terms of combustion stability, power output and emissions formation. Overall, 50-bar injection pressure and a late injection timing under WOT conditions achieved higher engine load levels with all injector nozzle types. Images acquired using an optical endoscope technique with a high-speed video camera showed that a yellow flame was present for all nozzle types at a low injection pressure and late SOI. Increasing the injection pressure reduced the injection duration, improved air/fuel mixing which resulted in the reduced byellow flame formation and lower PN for most of the nozzle heads

Why do commercial companies contribute to open source software?

This is the post-print version of the Article. The official published version can be accessed from the link belowMany researchers have pointed out that the opensource movement is an interesting phenomenon that is difficult to explain with conventional economic theories. However, while there is no shortage on research on individuals’ motivation for contributing to opensource, few have investigated the commercial companies’ motivations for doing the same. A case study was conducted at three different companies from the IT service industry, to investigate three possible drivers: sale of complimentary services, innovation and open sourcing (outsourcing). We offer three conclusions. First, we identified three main drivers for contributing to opensource, which are (a) selling complimentary services, (b) building greater innovative capability and (c) cost reduction through open sourcing to an external community. Second, while previous research has documented that the most important driver is selling complimentary services, we found that this picture is too simple. Our evidence points to a broader set of motivations, in the sense that all our cases exhibit combinations of the three drivers. Finally, our findings suggest that there might be a shift in how commercial companies view opensource software. The companies interviewed have all expressed a moral obligation to contribute to open source

How open is innovation? A retrospective and ideas forward

This paper sheds fresh light on our 2010 paper How Open Is Innovation by taking into consideration notable developments in innovation over the last decade. The original paper developed four types of openness: sourcing, acquiring, selling, and revealing. Reflecting on important technological, organizational, and societal changes in the past decade, we highlight how these changes prompt novel questions for open innovation. While the core features of the original framework still stands, there are many new questions that have emerged in recent years. We end by charting a path for future research that emphasizes opportunities, costs and tradeoffs between different modes of open innovation, the need to better understand the nature of data, new organizational designs and legal instruments, and multilevel aspects and relationships that affect the extent and nature of openness

Evaluation of a Back-up Range Extender and Other Heavy-Duty BEV-Supporting Systems

Electric powertrains in terms of battery electric vehicles (BEV) are considered to be very interesting for heavy truck transportations. The challenge is the need for very large onboard energy and batteries. Long-term fuel cells (FCs) are considered an interesting support system for heavy-duty BEV, but in the short term, a range extender (REX) is also interesting. A heavy-duty BEV with 970 kWh batteries installed can handle 27% of all possible missions for the Scania fleet considering daily recharging. The back-up range extender (BUREX) can expand this figure to 55% utilized 20 days per year. If a customer has a few very energy-demanding use cases each year and does not want to pay for all the batteries needed, the BUREX may be an especially good option. The BUREX reduces life-cycle CO2 emissions, irrespective of the generation mix of the grid supplying the electricity used in vehicle manufacturing and battery charging. The BUREX reuse of the existing electric components of the BEV powertrain enables the installation of a 10% larger battery pack while being 80% less costly. The BUREX also adds redundancy to the BEV concept while recharging infrastructure improves, especially in rural places. These results indicate that the BUREX concept is a powerful short-term solution that could enable greater use of HD FC and BEV trucks while charging infrastructure and FC technologies gradually become more mature

Blinded by the person? Experimental evidence from idea evaluation

Research Summary: Seeking causal evidence on biases in idea evaluation, we conducted a field experiment in a large multinational company with two conditions: (a) blind evaluation, in which managers received no proposer information, and (b) non-blind evaluation, in which they received the proposer\u27s name, unit, and location. To our surprise—and in contrast to the preregistered hypotheses—we found no biases against women and proposers from different units and locations, which blinding could ameliorate. Addressing challenges that remained intractable in the field experiment, we conducted an online experiment, which replicated the null findings. A final vignette study showed that people overestimated the magnitude of the biases. The studies suggest that idea evaluation can be less prone to biases than previously assumed and that evaluators separate ideas from proposers. Managerial Summary: We wanted to find out if there were biases in the way managers evaluate ideas from their employees. We did a field experiment in a large multinational technology company where we tested two different ways of evaluating ideas: one where managers did not know anything about the person who came up with the idea and one where they did know the person\u27s name, which unit they worked for, and where they were located. The results were surprising. We did not find any bias against women and employees that did not work in the same location and unit as the evaluator. Managers are advised that hiding the identity of idea proposers (from idea evaluators) may not be a silver bullet to improving idea evaluation

The new needs friends: Simmelian strangers and the selection of novelty

The paradox of rejecting novel ideas while being motivated to select them exists in many realms. Deviating from prior research that investigated several internal levers to promote the funding of novel ideas in the sciences, we focus on an external lever by investigating how seconded employees increase the selection of novel ideas in two ways: (1) they select more novel ideas themselves, and (2) they influence permanent employees to do the same. Combining unique quantitative longitudinal data and 37 in-depth interviews, we test our predictions in the secondment program at the National Science Foundation and find broad support for our theoretical arguments. Our findings have implications for scholars of science and innovation by proposing a relatively light-touch intervention to facilitate the selection of novel ideas

GitLab: work where you want, when you want

GitLab is a software company that works “all remote” at the scale of more than 1000 employees located in more than 60 countries. GitLab has no physical office and its employees can work from anywhere they choose. Any step of the organizational life of a GitLab employee (e.g., hiring, onboarding and firing) is performed remotely, except for a yearly companywide gathering. GitLab strongly relies on asynchronous coordination, allowing employees to work anytime they want. After highlighting some of the main practices implemented by GitLab to effectively work all remotely and asynchronously, I asked renowned organizational scientists their thoughts on this interesting case and to question the generalizability of the all remote asynchronous model. Understanding whether and under what conditions this model can succeed can be of guidance for organizational designers that are now considering different remote models in response of the COVID-19 shock and its aftermath