What the study found
Vertical vibrations changed how lunar regolith simulant moved through a hopper, making the flow more regular and reducing clogging, but the average mass flow rate stayed lower than in purely gravitational flow.
Why the authors say this matters
The authors state that hoppers are expected to be essential for handling lunar regolith in future lunar exploration missions, from collection and storage to in situ resource utilization, so understanding discharge behavior under vibration is relevant to those applications.
What the researchers tested
The researchers carried out a parametric experimental investigation using the LHS-1 lunar regolith simulant in a hopper-based conveying device. They examined how vibration frequency and amplitude affected discharge dynamics, flow patterns, mass flow rate, displacement patterns, and jamming behavior.
What worked and what didn't
Vibrations significantly reduced the probability of arching, which is a clogging bridge formed by particles, and made the flow more spatially uniform. However, the average mass flow rate was consistently smaller than in purely gravitational flow, and low frequencies universally promoted arching due to insufficient energy to disrupt force chains.
What to keep in mind
The abstract describes four observed flow configurations—funnel, mass, asymmetric, and ratholing—but it does not provide detailed experimental conditions for each in this summary. It also notes that the effect of vibration amplitude weakens as sample mass increases, suggesting that gravity-induced compaction and particle rearrangement dynamics may also matter, but further limitations are not described in the available abstract.
Key points
- Vertical vibrations made regolith simulant flow more regular and reduced clogging in a hopper.
- Average mass flow rate under vibration was still lower than in purely gravitational flow.
- Low vibration frequencies promoted arching because they did not provide enough energy to disrupt force chains.
- Four flow configurations were identified: funnel, mass, asymmetric, and ratholing.
- Higher vibration amplitude generally reduced blockage, but its effect weakened as sample mass increased.
Disclosure
- Research title:
- Vertical vibration changes regolith flow but lowers average discharge rate
- Authors:
- Marcello Lappa, Peter Watson, S. Vincent-Bonnieu
- Institutions:
- University of Strathclyde, European Space Agency, European Space Research and Technology Centre
- Publication date:
- 2026-04-21
- OpenAlex record:
- View
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